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Dummer. ゛☀
2017年08月08日
Also called Staghead or white blister, white rust disease affects cruciferous plants. These plants are all members of the cabbage family (Brassicaceae) and include such vegetables as broccoli, cauliflower, Brussels sprouts and kale and can ruin your crop.
White Rust Disease – What is White Rust?
What is white rust? It’s a disease that causes distinctive chalky white spore masses sometimes referred to as pustules that first show up on the underside of leaves. These blister-like masses, called sori, form under the leaf’s dermis (skin) and can’t be scraped off without damaging the leaf. The stem and leaves can become twisted and deformed. White rust disease can and will infect the floral parts as well. Broccoli and cauliflower, in particular, will produce grossly deformed heads and for those gardeners who collect seed for the following year’s planting, those seeds will be sterile. White rust is one of several species of the fungus Albugo. It commonly occurs when nights are cool and damp and days are warm. The perfect time for growing cruciferous vegetables also provides the perfect growing conditions for Albugo. Controlling white rust fungus would be easy if we could control those spring and fall temperatures since it flourishes between 57°F. and 68°F. (14° to 20°C.). Unfortunately, we can’t control temperature any more than we can control the spring rains or the dewy mornings this fungus adores.
White Rust Treatment
If your garden has been plagued by white rust disease in the past, you should look for resistant strains in the future. There are no fungicides specific to white rust treatment and once the disease becomes rampant, there is little to be done. That being said, fungicides used to treat downy mildew are sometimes effective against white rust, particularly the more leafy crops. Treatment must begin at the first signs of infection. The methods for controlling white rust fungus or how to prevent white rust are largely organic. The control of white rust fungus depends on the understanding of the life cycle of fungi in general. Fungi reproduce by producing spores, tiny microscopic cells, each of which is capable of becoming a fungi and thus establishing a new colony — what we see on the leaf or stem. Because of their minuscule size, these spores are carried easily from plant to plant, or garden to garden, by wind or water. Because of a protective coating, many of these spores can lay dormant for long periods of time, surviving in both cold and arid conditions. When conditions are right again, they ‘blossom.’ The secret to how to prevent white rust is two-fold. First is the removal of the places where the spores hide. Garden debris should never be left to overwinter. Even plant growth that looks healthy may be harboring spores waiting to spread the disease the following spring. Obviously infected debris should be disposed of away from the garden area. As it is almost impossible to collect and destroy every scrap of debris, consider tilling it under as another form of white rust treatment. While tilling won’t destroy the spores, it can prevent them from being exposed to the growing conditions they require.
he second step in controlling white rust fungus is crop rotation. Infected beds should not be replanted with cruciferous vegetables for at least three years. Remember, good garden housekeeping is essential in controlling white rust fungus as well as many other garden diseases; therefore, it should be a regular part of your gardening calendar. That old adage remains true: An ounce of prevention is worth a pound of cure.
White Rust Disease – What is White Rust?
What is white rust? It’s a disease that causes distinctive chalky white spore masses sometimes referred to as pustules that first show up on the underside of leaves. These blister-like masses, called sori, form under the leaf’s dermis (skin) and can’t be scraped off without damaging the leaf. The stem and leaves can become twisted and deformed. White rust disease can and will infect the floral parts as well. Broccoli and cauliflower, in particular, will produce grossly deformed heads and for those gardeners who collect seed for the following year’s planting, those seeds will be sterile. White rust is one of several species of the fungus Albugo. It commonly occurs when nights are cool and damp and days are warm. The perfect time for growing cruciferous vegetables also provides the perfect growing conditions for Albugo. Controlling white rust fungus would be easy if we could control those spring and fall temperatures since it flourishes between 57°F. and 68°F. (14° to 20°C.). Unfortunately, we can’t control temperature any more than we can control the spring rains or the dewy mornings this fungus adores.
White Rust Treatment
If your garden has been plagued by white rust disease in the past, you should look for resistant strains in the future. There are no fungicides specific to white rust treatment and once the disease becomes rampant, there is little to be done. That being said, fungicides used to treat downy mildew are sometimes effective against white rust, particularly the more leafy crops. Treatment must begin at the first signs of infection. The methods for controlling white rust fungus or how to prevent white rust are largely organic. The control of white rust fungus depends on the understanding of the life cycle of fungi in general. Fungi reproduce by producing spores, tiny microscopic cells, each of which is capable of becoming a fungi and thus establishing a new colony — what we see on the leaf or stem. Because of their minuscule size, these spores are carried easily from plant to plant, or garden to garden, by wind or water. Because of a protective coating, many of these spores can lay dormant for long periods of time, surviving in both cold and arid conditions. When conditions are right again, they ‘blossom.’ The secret to how to prevent white rust is two-fold. First is the removal of the places where the spores hide. Garden debris should never be left to overwinter. Even plant growth that looks healthy may be harboring spores waiting to spread the disease the following spring. Obviously infected debris should be disposed of away from the garden area. As it is almost impossible to collect and destroy every scrap of debris, consider tilling it under as another form of white rust treatment. While tilling won’t destroy the spores, it can prevent them from being exposed to the growing conditions they require.
he second step in controlling white rust fungus is crop rotation. Infected beds should not be replanted with cruciferous vegetables for at least three years. Remember, good garden housekeeping is essential in controlling white rust fungus as well as many other garden diseases; therefore, it should be a regular part of your gardening calendar. That old adage remains true: An ounce of prevention is worth a pound of cure.
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Dummer. ゛☀
2017年08月08日
You may know it as leaf, shoot or twig blight. It affects a variety of shrubs, trees and other plants. Combating anthracnose can be a frustrating process, leaving gardeners asking, “How do you treat anthracnose effectively?” Knowing more about what plants get anthracnose and how to prevent it can go a long way in successful anthracnose control. 
Anthracnose Disease Info
Anthracnose is a fungal disease that tends to attack plants in the spring when the weather is cool and wet, primarily on leaves and twigs. The fungi overwinter in dead twigs and fallen leaves. Cool, rainy weather creates perfect conditions for the spores to spread. Dry and hot weather stop the progression of the disease that may begin again once the weather conditions become optimal. The problem can be cyclic but is rarely fatal. Anthracnose fungus infects many deciduous and evergreen trees and shrubs, as well as fruits, vegetables and grass. Anthracnose is noticeable along the leaves and the veins as small lesions. These dark, sunken lesions may also be found on stems, flowers and fruits. In order to distinguish between anthracnose and other leaf spot diseases, you should carefully examine the undersides of leaves for a number of small tan to brown dots, about the size of a pin head. If you are unsure about diagnosing anthracnose, consult your local Cooperative Extension office for assistance and additional anthracnose disease info.
What Plants Get Anthracnose?
A wide variety of plants can be affected by anthracnose fungus, including those grown outside of a greenhouse, such as woody ornamentals and tropical foliage plants. Potted plants and greenhouse crops such as cyclamen, ficus, lupine, palms, succulents and yuccas are sometimes affected. Trees and shrubs that are prone to anthracnose include maple, camellia, walnut, ash, azalea, oak and sycamore.
How Do You Treat Anthracnose?
Anthracnose control begins with practicing good sanitation. Picking up and disposing of all diseased plant parts, including twigs and leaves, from the ground or from around the plant is important. This keeps the fungus from overwintering near the plant. Proper pruning techniques to rid trees and plants of old and dead wood also helps with prevention of anthracnose fungus. Keeping plants healthy by providing proper light, water and fertilizer will strengthen the plant’s ability to ward off a fungus attack. Stressed trees and plants have a difficult time recovering from anthracnose fungus. Chemical treatment is rarely used except when the disease involves newly transplanted plants or continual defoliation.
Anthracnose Disease Info
Anthracnose is a fungal disease that tends to attack plants in the spring when the weather is cool and wet, primarily on leaves and twigs. The fungi overwinter in dead twigs and fallen leaves. Cool, rainy weather creates perfect conditions for the spores to spread. Dry and hot weather stop the progression of the disease that may begin again once the weather conditions become optimal. The problem can be cyclic but is rarely fatal. Anthracnose fungus infects many deciduous and evergreen trees and shrubs, as well as fruits, vegetables and grass. Anthracnose is noticeable along the leaves and the veins as small lesions. These dark, sunken lesions may also be found on stems, flowers and fruits. In order to distinguish between anthracnose and other leaf spot diseases, you should carefully examine the undersides of leaves for a number of small tan to brown dots, about the size of a pin head. If you are unsure about diagnosing anthracnose, consult your local Cooperative Extension office for assistance and additional anthracnose disease info.
What Plants Get Anthracnose?
A wide variety of plants can be affected by anthracnose fungus, including those grown outside of a greenhouse, such as woody ornamentals and tropical foliage plants. Potted plants and greenhouse crops such as cyclamen, ficus, lupine, palms, succulents and yuccas are sometimes affected. Trees and shrubs that are prone to anthracnose include maple, camellia, walnut, ash, azalea, oak and sycamore.
How Do You Treat Anthracnose?
Anthracnose control begins with practicing good sanitation. Picking up and disposing of all diseased plant parts, including twigs and leaves, from the ground or from around the plant is important. This keeps the fungus from overwintering near the plant. Proper pruning techniques to rid trees and plants of old and dead wood also helps with prevention of anthracnose fungus. Keeping plants healthy by providing proper light, water and fertilizer will strengthen the plant’s ability to ward off a fungus attack. Stressed trees and plants have a difficult time recovering from anthracnose fungus. Chemical treatment is rarely used except when the disease involves newly transplanted plants or continual defoliation.
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Dummer. ゛☀
2017年08月08日
Before you decide to start crown gall treatment, consider the value of the plant you are treating. The bacteria that causes crown gall disease in plants persists in the soil as long as there are susceptible plants in the area. To eliminate the bacteria and prevent the spread, it’s best to remove and destroy diseased plants. What is Crown Gall? When learning about crown gall treatment, it helps to know more about what is crown gall in the first place. Plants with crown gall have swollen knots, called galls, near the crown and sometimes on the roots and twigs as well. The galls are tan in color and may be spongy in texture at first, but they eventually harden and turn dark brown or black. As the disease progresses, the galls can totally encircle the trunks and branches, cutting off the flow of sap that nourishes the plant. The galls are caused by a bacterium (Rhizobium radiobacter formerly Agrobacterium tumefaciens) that lives in the soil and enters the plant through injuries. Once inside the plant, the bacterium injects some of its genetic material into the host’s cells, causing it to produce hormones that stimulate small areas of rapid growth.
How to Fix Crown Gall
Unfortunately, the best course of action for plants affected by crown gall is to remove and destroy the infected plant. The bacteria can persist in the soil for two years after the plant is gone, so avoid planting any other susceptible plants in the area until the bacteria dies out for lack of a host plant. Prevention is an essential aspect of dealing with crown gall. Inspect plants carefully before you buy them, and reject any plants with swollen knots. The disease can enter the plant in the nursery through the graft union, so pay particular attention to this area.
To prevent the bacteria from entering the plant once you get it home, avoid wounds near the ground as much as possible. Use string trimmers with care and mow the lawn so that debris flies away from susceptible plants. Galltrol is a product that contains a bacterium that competes with Rhizobium radiobacter and prevents it from entering wounds. A chemical eradicant called Gallex may also help prevent the crown gall disease in plants. Although these products are sometimes recommended for crown gall treatment, they are more effective when used as a preventative before the bacteria infects the plant.
Plants Affected by Crown Gall Over 600 different plants are affected by crown gall, including these common landscape plants: Fruit trees, particularly apples and members of the Prunus family, which includes cherries and plums Roses and members of the rose family Raspberries and blackberries Willow trees Wisteria
How to Fix Crown Gall
Unfortunately, the best course of action for plants affected by crown gall is to remove and destroy the infected plant. The bacteria can persist in the soil for two years after the plant is gone, so avoid planting any other susceptible plants in the area until the bacteria dies out for lack of a host plant. Prevention is an essential aspect of dealing with crown gall. Inspect plants carefully before you buy them, and reject any plants with swollen knots. The disease can enter the plant in the nursery through the graft union, so pay particular attention to this area.
To prevent the bacteria from entering the plant once you get it home, avoid wounds near the ground as much as possible. Use string trimmers with care and mow the lawn so that debris flies away from susceptible plants. Galltrol is a product that contains a bacterium that competes with Rhizobium radiobacter and prevents it from entering wounds. A chemical eradicant called Gallex may also help prevent the crown gall disease in plants. Although these products are sometimes recommended for crown gall treatment, they are more effective when used as a preventative before the bacteria infects the plant.
Plants Affected by Crown Gall Over 600 different plants are affected by crown gall, including these common landscape plants: Fruit trees, particularly apples and members of the Prunus family, which includes cherries and plums Roses and members of the rose family Raspberries and blackberries Willow trees Wisteria
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Dummer. ゛☀
2017年08月08日
While many people have both heard of and dealt with root rot in houseplants, most are not aware that this disease can also have an adverse effect on garden plants outdoors, including shrubs and trees. Learning more about the cause of root rot and how to look for early signs of root rot in garden plants will go a long way in its treatment. For root rot prevention and treatment info, keep reading. What is Root Rot? Root rot is a disease that attacks the roots of plants growing in wet soil. Since the disease spreads through the soil, the only root rot remedy for garden plants is often to remove and destroy the plant. However, you can try these corrective measures if you want to attempt to save a particularly valuable plant: Keep the soil as dry as possible. Don’t irrigate the plant unless the soil is almost completely dry. Pull back the soil to allow moisture to evaporate from the soil. The cause of root rot is a fungus. Species of the Pythium, Phytophthora, Rhizoctonia, or Fusarium fungi are the usual culprits. These fungi thrive in wet soil, and you can transfer them from one part of the garden to another when you transplant ailing plants.
When it comes to identifying root rot, look at the plants. Plants with root rot can’t absorb moisture and nourishment from the soil properly. The plants often resemble those suffering from drought and stress and mineral deficiencies. Signs of root rot in garden plants include stunting, wilting and discolored leaves. Foliage and shoots die back and the entire plant soon dies. If you pull up a plant with root rot, you will see that the roots are brown and soft instead of firm and white. Trees with root rot develop cankers, ooze reddish or black sap, and sometimes develop dark vertical streaks. Treatment for Root Rot The best root rot remedy for garden plants is prevention. Prevent root rot by filling in low parts of the garden and improving the soil with organic matter so that it drains freely. If you can’t improve the drainage, use raised beds where the where plant roots sit above the soil. Taking care not to overwater garden plants will also help. There are chemical fungicides and biological agents labeled as treatment for root rot disease; however, you should not use these products unless you know which fungus is causing the problem.
Once you know which fungus you are treating, your agricultural extension agent can recommend a product to treat that specific fungus. Fungicides are toxic chemicals that should be used with caution. Read the label and follow the instructions exactly. Store them in their original container and out of the reach of children. Even when all of the precautions are taken in the garden, root rot may still occasionally become an issue. However, if you pay attention to the signs of root rot in garden plants, you’ll have a better chance of saving your plants.
When it comes to identifying root rot, look at the plants. Plants with root rot can’t absorb moisture and nourishment from the soil properly. The plants often resemble those suffering from drought and stress and mineral deficiencies. Signs of root rot in garden plants include stunting, wilting and discolored leaves. Foliage and shoots die back and the entire plant soon dies. If you pull up a plant with root rot, you will see that the roots are brown and soft instead of firm and white. Trees with root rot develop cankers, ooze reddish or black sap, and sometimes develop dark vertical streaks. Treatment for Root Rot The best root rot remedy for garden plants is prevention. Prevent root rot by filling in low parts of the garden and improving the soil with organic matter so that it drains freely. If you can’t improve the drainage, use raised beds where the where plant roots sit above the soil. Taking care not to overwater garden plants will also help. There are chemical fungicides and biological agents labeled as treatment for root rot disease; however, you should not use these products unless you know which fungus is causing the problem.
Once you know which fungus you are treating, your agricultural extension agent can recommend a product to treat that specific fungus. Fungicides are toxic chemicals that should be used with caution. Read the label and follow the instructions exactly. Store them in their original container and out of the reach of children. Even when all of the precautions are taken in the garden, root rot may still occasionally become an issue. However, if you pay attention to the signs of root rot in garden plants, you’ll have a better chance of saving your plants.
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Dummer. ゛☀
2017年08月08日
Aster yellows can affect a myriad of plants and is often quite detrimental to them as well. Keep reading to learn more about this problem and how to control aster yellows on flowers and other plants in the garden. What is Aster Yellows? Aster yellows on flowers isn’t really caused by a virus at all. It is caused by a cross between a bacterium and virus called a phytoplasma, and for such a tiny organism; it can cause a great deal of trouble. Flower hosts of aster yellows are too numerous to list, as it affects more than two hundred species in over 40 plant families. Aster yellows virus is a disease carried from an infected plant to a healthy one by a creature known to entomologists as Macrosteles fascifrons and to gardeners as aster leafhopper. These, too, are tiny little creatures that gardeners often describe as gnats.
They are only 4 mm. long and their semi-transparent wings are brown or greenish. Easily disturbed, these carriers of aster yellows virus often go unnoticed until it is too late. Like all Homopterean insects, aster leafhoppers have sucking mouthparts called stylets, which are used to suck the juices from the tissues of plants. As they feed, the leafhoppers leave some of their saliva behind. If the insect has fed on a plant host of aster yellows, the phytoplasma from one plant will be deposited in another and so on and so on. Most aster leafhoppers originate in the warm temperatures of the south. They then begin feeding in the area where they were hatched and steadily migrate northward spreading the aster yellows virus just as new seedlings emerge or are planted in their path. Some of these migrant leafhoppers will lay more eggs as they travel and prefer to do so in grain-producing crops such as wheat. Gardeners who live in such areas are, therefore, more likely to see the aster yellows virus on flowers than those who live beyond those areas. These native leafhoppers are more likely to infect older, more established plants where symptoms will be less obvious. Hosts of Aster Yellows While named for the members of the family Asteraceae in which it was first discovered, everything from garden vegetables as diverse as broccoli, carrots and potatoes to flowering plants such as phlox, gladioli and coneflowers can fall victim to this insidious disease. Diagnosing the problem of aster yellows virus can be difficult as well. Its symptoms vary from species to species and it is often mistaken for other diseases or herbicide damage. Infected foliage can be discolored and twisted. The normal green may be replaced with yellow or red.
Hosts of aster yellows may first show the unsightly ‘witches broom‘ of terminal growth. Tall plants may appear bushy and stunted. Leaf veins often turn yellow or white before the entire leaf becomes chlorotic or lacking the chlorophyll green the plant needs to survive. This is the opposite of nutrient deficiency where the veins remain green. Carrots with red leaves and bitter tap roots dotted with white fuzz are indicative of aster yellows. On flowers, the disease may cause twisted heads that remain green or as with marigolds, blossom in a muddy orange mess. Aster Yellows on Flowers – Controlling Aster Yellows Disease Controlling aster yellows is difficult. There is no treatment currently available for curing the disease and plant removal to prevent more spread is the only course of action. Destroying the insect vector is nearly impossible, but certain insecticides such as carbaryl, diazinon and permethrin may help. Read the label before applying any insecticide to your garden. Controlling aster yellows organically involves having a healthy number of beneficial insects in your garden. Neem oil is effective, but may limit beneficial insect numbers. Insecticidal soaps are not considered harmful to bees, but will reduce the number of beneficial insects.
If you live in an area where the disease is common, the best method of controlling aster yellows on flowers and vegetables may be to plant flowers that are immune to the disease, such as geraniums and impatiens. Your local extension service may be able to help you choose plants that are readily available in your area.
They are only 4 mm. long and their semi-transparent wings are brown or greenish. Easily disturbed, these carriers of aster yellows virus often go unnoticed until it is too late. Like all Homopterean insects, aster leafhoppers have sucking mouthparts called stylets, which are used to suck the juices from the tissues of plants. As they feed, the leafhoppers leave some of their saliva behind. If the insect has fed on a plant host of aster yellows, the phytoplasma from one plant will be deposited in another and so on and so on. Most aster leafhoppers originate in the warm temperatures of the south. They then begin feeding in the area where they were hatched and steadily migrate northward spreading the aster yellows virus just as new seedlings emerge or are planted in their path. Some of these migrant leafhoppers will lay more eggs as they travel and prefer to do so in grain-producing crops such as wheat. Gardeners who live in such areas are, therefore, more likely to see the aster yellows virus on flowers than those who live beyond those areas. These native leafhoppers are more likely to infect older, more established plants where symptoms will be less obvious. Hosts of Aster Yellows While named for the members of the family Asteraceae in which it was first discovered, everything from garden vegetables as diverse as broccoli, carrots and potatoes to flowering plants such as phlox, gladioli and coneflowers can fall victim to this insidious disease. Diagnosing the problem of aster yellows virus can be difficult as well. Its symptoms vary from species to species and it is often mistaken for other diseases or herbicide damage. Infected foliage can be discolored and twisted. The normal green may be replaced with yellow or red.
Hosts of aster yellows may first show the unsightly ‘witches broom‘ of terminal growth. Tall plants may appear bushy and stunted. Leaf veins often turn yellow or white before the entire leaf becomes chlorotic or lacking the chlorophyll green the plant needs to survive. This is the opposite of nutrient deficiency where the veins remain green. Carrots with red leaves and bitter tap roots dotted with white fuzz are indicative of aster yellows. On flowers, the disease may cause twisted heads that remain green or as with marigolds, blossom in a muddy orange mess. Aster Yellows on Flowers – Controlling Aster Yellows Disease Controlling aster yellows is difficult. There is no treatment currently available for curing the disease and plant removal to prevent more spread is the only course of action. Destroying the insect vector is nearly impossible, but certain insecticides such as carbaryl, diazinon and permethrin may help. Read the label before applying any insecticide to your garden. Controlling aster yellows organically involves having a healthy number of beneficial insects in your garden. Neem oil is effective, but may limit beneficial insect numbers. Insecticidal soaps are not considered harmful to bees, but will reduce the number of beneficial insects.
If you live in an area where the disease is common, the best method of controlling aster yellows on flowers and vegetables may be to plant flowers that are immune to the disease, such as geraniums and impatiens. Your local extension service may be able to help you choose plants that are readily available in your area.
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Dummer. ゛☀
2017年08月08日
It happens to the best of us. Your garden grows so nice and then, without any warning, you turn around and notice all your healthy plants wilting and dying. Southern blight on plants is a common problem in many home gardens but it doesn’t have to be. How do you control southern blight before it takes out all of your plants? Keep reading to find out ways for controlling southern blight in gardens. What is Southern Blight? Southern blight, southern wilt, southern stem rot and southern root rot all refer to the same disease.
It is caused by the soil borne fungus Sclerotium rolfsii. The disease attacks a wide range of vegetable crops and ornamental plants at or below the soil line. Southern blight on plants is most likely to occur in the summer months when the soil is warm and moist. Symptoms include discolored lower leaves, wilted foliage and plant collapse; and it usually results in the death of the plant. Upon close inspection, you may find an abundance of white hyphae or mycelia around the lower stem and roots, and in the surrounding soil. When you find the hyphae or mycelia, the best course of action is to dispose of the plant and the soil surrounding it. How Do You Control Southern Blight? Controlling southern blight in the home garden is a challenge because the fungicides that are effective in treating the disease are only available to commercial growers. Home gardeners must depend on cultural practices to control the disease. In the home garden, southern blight treatment begins with good sanitation to prevent the spread of the disease. The disease organism travels around the garden in bits of soil that clings to garden tools and the soles of shoes.
Remove the soil before moving from one part of the garden to another. Quarantine new plants by growing them in a bed that is isolated from the rest of the garden until you are sure they are disease-free. Remove and destroy diseased plants, along with the surrounding soil and any garden debris or mulch that has come in contact with them. Don’t transplant any nearby plants to other parts of the garden. Soil solarization is an effective method of killing the fungus in the South, but in northern climates, the soil temperatures may not be high enough to eradicate the disease. Cover the soil with a clear plastic tarp and leave it in place while the heat builds up under it.
The top two inches of soil must come to a temperature of at least 122 F. (50 C.) to kill the fungus. If all else fails, consider calling in a landscape professional to treat your garden soil with the appropriate fungicides specified for southern blight treatment.
It is caused by the soil borne fungus Sclerotium rolfsii. The disease attacks a wide range of vegetable crops and ornamental plants at or below the soil line. Southern blight on plants is most likely to occur in the summer months when the soil is warm and moist. Symptoms include discolored lower leaves, wilted foliage and plant collapse; and it usually results in the death of the plant. Upon close inspection, you may find an abundance of white hyphae or mycelia around the lower stem and roots, and in the surrounding soil. When you find the hyphae or mycelia, the best course of action is to dispose of the plant and the soil surrounding it. How Do You Control Southern Blight? Controlling southern blight in the home garden is a challenge because the fungicides that are effective in treating the disease are only available to commercial growers. Home gardeners must depend on cultural practices to control the disease. In the home garden, southern blight treatment begins with good sanitation to prevent the spread of the disease. The disease organism travels around the garden in bits of soil that clings to garden tools and the soles of shoes.
Remove the soil before moving from one part of the garden to another. Quarantine new plants by growing them in a bed that is isolated from the rest of the garden until you are sure they are disease-free. Remove and destroy diseased plants, along with the surrounding soil and any garden debris or mulch that has come in contact with them. Don’t transplant any nearby plants to other parts of the garden. Soil solarization is an effective method of killing the fungus in the South, but in northern climates, the soil temperatures may not be high enough to eradicate the disease. Cover the soil with a clear plastic tarp and leave it in place while the heat builds up under it.
The top two inches of soil must come to a temperature of at least 122 F. (50 C.) to kill the fungus. If all else fails, consider calling in a landscape professional to treat your garden soil with the appropriate fungicides specified for southern blight treatment.
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Dummer. ゛☀
2017年08月08日
Many ornamental and edible plants display dark, necrotic looking spots on their leaves. This is a symptom of bacterial leaf spot disease. Bacterial leaf spot on plants will discolor, and in extreme cases, kill leaves. Tiny, microscopic single celled organisms are what causes bacterial leaf spot. There are several methods on how to treat bacterial leaf spot and save your plant’s glorious leaves. Early identification is crucial to effective management of bacterial leaf spot disease. Symptoms of Bacterial Leaf Spot Bacterial leaf spot on plants may manifest in several different ways. Symptoms of bacterial leaf spot may include black edged lesions, brown spots with yellow halos or just light and dark areas on the foliage. Spots are irregular and measure between 3/16 and ½ inch wide. They can occur on the top or bottom of a leaf and kill sections of the tissue when they cluster together.
Symptoms of bacterial leaf spot may also appear on the edges of a leaf, where it appears brownish yellow and the tissue dries and breaks off. The leaves become quite papery and delicate when the bacterial disease attacks leaf edges. The disease is most prevalent on older leaves but will quickly establish on newer tissue. What Causes Bacterial Leaf Spot? Organisms that cannot be seen with the naked eye are the cause of this visibly damaging plant disease. Wet, cool conditions promote the formation of these bacteria, which can spread on plants quickly. The bacteria splash onto leaves or overwinter on plant debris in soil. Bacteria divide to reproduce and one bacterium can multiply quickly in just a matter of hours. Bacteria reproduce the fastest when temperatures are 77-86 F. (25-30 C.). High rates of infection will cause leaf loss and can seriously compromise a plants health. This makes the disease extremely contagious and bacterial leaf spot disease treatment extremely important.
The pathogen is also carried in infected seed; however, there are some disease resistant seed strains for food crops. Additionally, choose disease free transplants, rotate crops and avoid overhead watering to prevent spreading the bacteria. How to Treat Bacterial Leaf Spot In addition to the previous tips on preventing spread of the disease, you can use a copper fungicide on crops. This has limited management use unless it is applied early in the disease cycle. On ornamental plants, remove the affected leaves at the first sign to prevent the bacteria from jumping onto adjacent leaves. Some of the most common hosts are lettuce, beets, eggplant, peppers and large leaved ornamental plants, such as philodendrons.
Remove old vegetable debris in the garden and do not plant new crops where host plants were once growing. There are no recognized chemical treatments for bacterial leaf spot disease. Your best bet is prevention and mechanical control at the first sign of symptoms of bacterial leaf spot.
Symptoms of bacterial leaf spot may also appear on the edges of a leaf, where it appears brownish yellow and the tissue dries and breaks off. The leaves become quite papery and delicate when the bacterial disease attacks leaf edges. The disease is most prevalent on older leaves but will quickly establish on newer tissue. What Causes Bacterial Leaf Spot? Organisms that cannot be seen with the naked eye are the cause of this visibly damaging plant disease. Wet, cool conditions promote the formation of these bacteria, which can spread on plants quickly. The bacteria splash onto leaves or overwinter on plant debris in soil. Bacteria divide to reproduce and one bacterium can multiply quickly in just a matter of hours. Bacteria reproduce the fastest when temperatures are 77-86 F. (25-30 C.). High rates of infection will cause leaf loss and can seriously compromise a plants health. This makes the disease extremely contagious and bacterial leaf spot disease treatment extremely important.
The pathogen is also carried in infected seed; however, there are some disease resistant seed strains for food crops. Additionally, choose disease free transplants, rotate crops and avoid overhead watering to prevent spreading the bacteria. How to Treat Bacterial Leaf Spot In addition to the previous tips on preventing spread of the disease, you can use a copper fungicide on crops. This has limited management use unless it is applied early in the disease cycle. On ornamental plants, remove the affected leaves at the first sign to prevent the bacteria from jumping onto adjacent leaves. Some of the most common hosts are lettuce, beets, eggplant, peppers and large leaved ornamental plants, such as philodendrons.
Remove old vegetable debris in the garden and do not plant new crops where host plants were once growing. There are no recognized chemical treatments for bacterial leaf spot disease. Your best bet is prevention and mechanical control at the first sign of symptoms of bacterial leaf spot.
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Dummer. ゛☀
2017年08月08日
There is a fungus among us and its name is Fusarium. This soil-borne pathogen attacks many types of plants, with ornamental flowers and some vegetables topping the list. Fusarium fungus can survive indefinitely, affecting any crop or plant that is contaminated by the soil. The fungus produces Fusarium wilt disease, which is also called “yellows.” This self- explanatory name indicates the major symptom of the disease. In crop and greenhouse settings, controlling Fusarium wilt is of primary importance, as it has the capacity to run rampant among closely grown plants. About Fusarium Fungus The fungus attacks plants in the nightshade family, such as tomatoes and peppers. It is also found in greenhouse flowers and some trees. 
Fusarium enters the roots of young plants and the organism blocks vessels in the cells. Once blocked, the cells cannot transport water and nutrients to the plant. The wilting symptom is one of the first signs that the pathogen is present. Fusarium wilt disease then progresses to faded, yellowed foliage and stunted growth. The worst signs are during the day in sunlight, but the plant may seem to recover in the dark. Over time, many plants succumb and die, while others just perform poorly and produce few flowers or fruit. Because of the contagious and tenacious nature of the fungus, control of Fusarium should start with a few evasive procedures. Preventing the fungal wilt is preferable to most Fusarium wilt treatments. Controlling Fusarium Wilt Fusarium is most prevalent in warm soils. It is harbored in old plant debris and soil. The best way to prevent infection in your crops or plants is rotation and sterilization.
Never plant the same crop in the same place annually. Pots should be sterilized with a bleach solution and new soil used when reusing them. You can also solarize beds, by spreading black plastic over an area in full sun for a month to kill the fungus. This causes extreme high temperatures that will “cook” the fungus and provide good control of Fusarium. Wash off tillage equipment, shoes and other tools that might have encountered infected soil. Remove all old plant debris annually and if you think it might be contaminated, burn it. Do not compost contaminated material as this provides an ideal incubation condition for propagating the fungus. Fusarium Wilt Treatment There are fumigants that are useful against Fusarium fungus. Many of these require a professional for application so read the instructions carefully before you purchase.
Fungicides are used as a root or bulb soak. Simply remove the soil from around the roots, bulb, corm or tuber and rinse completely. Then soak the roots or storage organs in a bucket of fresh water with the appropriate amount of a fungicide. Controlling Fusarium fungus in the garden relies upon crop rotations and clean and sanitary practices. Always inspect new plants before you purchase them. Remember, prevention is the best method of control of Fusarium and many other plant diseases.
Fusarium enters the roots of young plants and the organism blocks vessels in the cells. Once blocked, the cells cannot transport water and nutrients to the plant. The wilting symptom is one of the first signs that the pathogen is present. Fusarium wilt disease then progresses to faded, yellowed foliage and stunted growth. The worst signs are during the day in sunlight, but the plant may seem to recover in the dark. Over time, many plants succumb and die, while others just perform poorly and produce few flowers or fruit. Because of the contagious and tenacious nature of the fungus, control of Fusarium should start with a few evasive procedures. Preventing the fungal wilt is preferable to most Fusarium wilt treatments. Controlling Fusarium Wilt Fusarium is most prevalent in warm soils. It is harbored in old plant debris and soil. The best way to prevent infection in your crops or plants is rotation and sterilization.
Never plant the same crop in the same place annually. Pots should be sterilized with a bleach solution and new soil used when reusing them. You can also solarize beds, by spreading black plastic over an area in full sun for a month to kill the fungus. This causes extreme high temperatures that will “cook” the fungus and provide good control of Fusarium. Wash off tillage equipment, shoes and other tools that might have encountered infected soil. Remove all old plant debris annually and if you think it might be contaminated, burn it. Do not compost contaminated material as this provides an ideal incubation condition for propagating the fungus. Fusarium Wilt Treatment There are fumigants that are useful against Fusarium fungus. Many of these require a professional for application so read the instructions carefully before you purchase.
Fungicides are used as a root or bulb soak. Simply remove the soil from around the roots, bulb, corm or tuber and rinse completely. Then soak the roots or storage organs in a bucket of fresh water with the appropriate amount of a fungicide. Controlling Fusarium fungus in the garden relies upon crop rotations and clean and sanitary practices. Always inspect new plants before you purchase them. Remember, prevention is the best method of control of Fusarium and many other plant diseases.
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Dummer. ゛☀
2017年08月08日
If you’ve noticed an outbreak of leaf mottling along with blistering or leaf curl in the garden, then you may have plants affected by TMV. Tobacco mosaic damage is caused by a virus and is prevalent in a variety of plants. So exactly what is tobacco mosaic virus? Keep reading to find out more, as well as how to treat tobacco mosaic virus once it’s found. What is Tobacco Mosaic Virus? Although tobacco mosaic virus (TMV) is named for the first plant in which it was discovered (tobacco) back in the 1800s, it infects over 150 different types of plants.
Among plants affected by TMV are vegetables, weeds and flowers. Tomato, pepper and many ornamental plants are struck annually with TMV. The virus does not produce spores but spreads mechanically, entering plants via wounds. History of Tobacco Mosaic Two scientists made the discovery of the first virus, the Tobacco Mosaic Virus, in the late 1800’s. Although it was known to be a damaging infectious disease, tobacco mosaic was not identified as a virus until 1930. Tobacco Mosaic Damage Tobacco mosaic virus does not usually kill the plant that is infected; it does cause damage to flowers, leaves and fruit and stunts a plant’s growth, however. With tobacco mosaic damage, leaves may appear mottled with dark green and yellow-blistered areas. The virus also causes leaves to curl. Symptoms tend to vary in severity and type depending on the light conditions, moisture, nutrients and temperature. Touching the infected plant and handling a healthy plant that may have a tear or nick, whereby the virus can enter, will spread the virus.
Pollen from an infected plant can also spread the virus, and seeds from a diseased plant can bring the virus to a new area. Insects that chew on plant parts may carry the disease as well. How to Treat Tobacco Mosaic Disease There has not yet been found a chemical treatment that effectively protects plants from TMV. In fact, the virus has been known to survive for up to 50 years in dried plant parts. The best control of the virus is prevention. Reducing and eliminating sources of the virus and the spread of insects can keep the virus kept under control. Sanitation is the key to success.
Garden tools should be kept sterilized. Any small plants that appear to have the virus should be removed immediately from the garden. All plant debris, dead and diseased, should be removed as well to prevent the spread of the disease. In addition, it is always best to avoid smoking while working in the garden, as tobacco products can be infected and this can spread from gardener’s hands to plants. Crop rotation is also an effective way to protect plants from TMV. Virus-free plants should be purchased to help avoid bringing the disease into the garden.
Among plants affected by TMV are vegetables, weeds and flowers. Tomato, pepper and many ornamental plants are struck annually with TMV. The virus does not produce spores but spreads mechanically, entering plants via wounds. History of Tobacco Mosaic Two scientists made the discovery of the first virus, the Tobacco Mosaic Virus, in the late 1800’s. Although it was known to be a damaging infectious disease, tobacco mosaic was not identified as a virus until 1930. Tobacco Mosaic Damage Tobacco mosaic virus does not usually kill the plant that is infected; it does cause damage to flowers, leaves and fruit and stunts a plant’s growth, however. With tobacco mosaic damage, leaves may appear mottled with dark green and yellow-blistered areas. The virus also causes leaves to curl. Symptoms tend to vary in severity and type depending on the light conditions, moisture, nutrients and temperature. Touching the infected plant and handling a healthy plant that may have a tear or nick, whereby the virus can enter, will spread the virus.
Pollen from an infected plant can also spread the virus, and seeds from a diseased plant can bring the virus to a new area. Insects that chew on plant parts may carry the disease as well. How to Treat Tobacco Mosaic Disease There has not yet been found a chemical treatment that effectively protects plants from TMV. In fact, the virus has been known to survive for up to 50 years in dried plant parts. The best control of the virus is prevention. Reducing and eliminating sources of the virus and the spread of insects can keep the virus kept under control. Sanitation is the key to success.
Garden tools should be kept sterilized. Any small plants that appear to have the virus should be removed immediately from the garden. All plant debris, dead and diseased, should be removed as well to prevent the spread of the disease. In addition, it is always best to avoid smoking while working in the garden, as tobacco products can be infected and this can spread from gardener’s hands to plants. Crop rotation is also an effective way to protect plants from TMV. Virus-free plants should be purchased to help avoid bringing the disease into the garden.
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Dummer. ゛☀
2017年08月08日
No matter how closely you listen to your plants, you’ll never hear a single “Achoo!” from the garden, even if they’re infected with viruses or bacteria. Although plants express these infections differently from humans, some gardeners worry about plant disease transmission to humans — after all, we can get viruses and bacteria, too, right? Can Plant Bacteria Infect a Human? Although it would seem like a no brainer to assume that plant and human diseases are distinct and cannot crossover from plant to gardener, this isn’t the case at all. Human infection from plants is very rare, but it does happen. The primary pathogen of concern is a bacteria known as Pseudomonas aeruginosa, which causes a type of soft rot in plants.
P. aeruginosa infections in humans can invade nearly any tissue in the human body, provided they are already weakened. Symptoms vary widely, from urinary tract infections to dermatitis, gastrointestinal infections and even systemic illness. To make matters worse, this bacterium is becoming increasingly antibiotic resistant in institutional settings. But wait! Before you run to the garden with a can of Lysol, be aware that even in severely ill, hospitalized patients, the infection rate of P. aeruginosa is only 0.4 percent, making it highly unlikely that you will ever develop an infection even if you have open wounds that come in contact with infected plant tissues. Normally-functioning human immune systems make human infection from plants highly improbable.
Do Plant Viruses Make People Sick? Unlike bacteria that can function in a more opportunistic fashion, viruses need very exacting conditions to spread. Even if you eat fruits from your squash mosaic infected melons, you won’t contract the virus responsible for this disease (Note: eating fruits from virus-infected plants isn’t recommended — they’re not usually very tasty but won’t hurt you.). You should always cull virus-infected plants as soon as you realize they’re present in your garden, since they are often vectored from sick plants to healthy ones by sap-sucking insects. Now you can dive in, pruners blazin’, confident that there’s not a significant connection between plant diseases and humans.
P. aeruginosa infections in humans can invade nearly any tissue in the human body, provided they are already weakened. Symptoms vary widely, from urinary tract infections to dermatitis, gastrointestinal infections and even systemic illness. To make matters worse, this bacterium is becoming increasingly antibiotic resistant in institutional settings. But wait! Before you run to the garden with a can of Lysol, be aware that even in severely ill, hospitalized patients, the infection rate of P. aeruginosa is only 0.4 percent, making it highly unlikely that you will ever develop an infection even if you have open wounds that come in contact with infected plant tissues. Normally-functioning human immune systems make human infection from plants highly improbable.
Do Plant Viruses Make People Sick? Unlike bacteria that can function in a more opportunistic fashion, viruses need very exacting conditions to spread. Even if you eat fruits from your squash mosaic infected melons, you won’t contract the virus responsible for this disease (Note: eating fruits from virus-infected plants isn’t recommended — they’re not usually very tasty but won’t hurt you.). You should always cull virus-infected plants as soon as you realize they’re present in your garden, since they are often vectored from sick plants to healthy ones by sap-sucking insects. Now you can dive in, pruners blazin’, confident that there’s not a significant connection between plant diseases and humans.
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Dummer. ゛☀
2017年08月08日
It can be difficult to differentiate between leaf-related problems that occur in the summer garden, but angular leaf spot disease is pretty distinctive, making it easy for new gardeners to diagnose successfully. Plants that develop very regular leaf spots that follow veins may be suffering from this disease. Read on to find out more. What is Angular Leaf Spot? Angular leaf spot in plants is caused by several bacteria that survive in seeds and plant debris, including Pseudomonas syringae and Xanthomonas fragariae. These bacteria are somewhat host-specific, with P.
syringae targeting cucurbits and X. fragariae attacking strawberries. Symptoms first appear as small, water-soaked spots on leaves, but spread rapidly when conditions are moist and ambient temperatures are between 75 and 82 F. (24-28 C.). Spots expand until they fill the entire area between leaf veins, but do not cross over, which creates a tiled appearance on larger leaves. Older spots may dry out and tear, leaving holes behind. On fruits, angular leaf spot disease manifests as perfectly circular, water-soaked spots, much smaller than those on the leaves. As the disease progresses, the spots take on a chalky white appearance and may crack open, allowing pathogens to contaminate fruits and cause fruit rot.
How to Treat Angular Leaf Spot Treating angular leaf spot is not a simple, straightforward task. Once a plant is infected, it cannot be cured easily and most gardeners will remove the plant from their garden to prevent further spreading of the disease. Future problems can be prevented by only using certified, disease-free seed, practicing a three-year crop rotation with different plant families and making a habit out of cleaning up plant debris as it falls to the ground.
Beds with poor drainage or that are over-watered favor angular leaf spot — pay close attention to your watering habits if this disease has already developed in your plants. Before watering, check the soil moisture level with your hand. Unless the top 1 to 2 inches of soil feel dry to the touch, do not water; and when you do, make sure to water at the base of plants. Good watering practices can reduce the risk of many diseases, including angular leaf spots in plants.
syringae targeting cucurbits and X. fragariae attacking strawberries. Symptoms first appear as small, water-soaked spots on leaves, but spread rapidly when conditions are moist and ambient temperatures are between 75 and 82 F. (24-28 C.). Spots expand until they fill the entire area between leaf veins, but do not cross over, which creates a tiled appearance on larger leaves. Older spots may dry out and tear, leaving holes behind. On fruits, angular leaf spot disease manifests as perfectly circular, water-soaked spots, much smaller than those on the leaves. As the disease progresses, the spots take on a chalky white appearance and may crack open, allowing pathogens to contaminate fruits and cause fruit rot.
How to Treat Angular Leaf Spot Treating angular leaf spot is not a simple, straightforward task. Once a plant is infected, it cannot be cured easily and most gardeners will remove the plant from their garden to prevent further spreading of the disease. Future problems can be prevented by only using certified, disease-free seed, practicing a three-year crop rotation with different plant families and making a habit out of cleaning up plant debris as it falls to the ground.
Beds with poor drainage or that are over-watered favor angular leaf spot — pay close attention to your watering habits if this disease has already developed in your plants. Before watering, check the soil moisture level with your hand. Unless the top 1 to 2 inches of soil feel dry to the touch, do not water; and when you do, make sure to water at the base of plants. Good watering practices can reduce the risk of many diseases, including angular leaf spots in plants.
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Dummer. ゛☀
2017年08月08日
You can tell a lot about your plant’s health from its leaves. When they’re green, shiny and flexible, all systems are go; that plant is happy and care-free. But when plants develop brown leaves in the middle of their canopy or leaf browning in center of leaves, problems are afoot. Most of the time, these symptoms can be traced back to improper growing conditions, but they may also be caused by fungi and viruses.
Causes for Plants Going Brown in Center Crown and Root Rot The center rotting out of a plant is almost always related to crown or root rot. Most plants can’t tolerate a soggy environment, especially those with crowns densely covered with leaves, like African violets. When you keep the soil wet all the time, fungal pathogens take advantage of the humidity that develops under the leaves of these low-growing plants, reproducing rapidly. Both root and crown rot can appear similar in these short plants, with the plants going brown in the center as the disease progresses. If you’re asking yourself, “What is causing brown leaves in center of my plant,” you need to check the soil moisture first. Allow the top inch or two of soil to dry between waterings and never leave plants soaking in water-filled saucers. Plants with root rot may be saved if you catch it in an early stage. Dig your plant, trim out any brown, black or soggy roots and replant into a well-draining medium — chemicals won’t help, the only thing that will fix root rot is a drier environment.
Diseases That Cause Brown Leaves Other reasons why leaves turn brown in middle include fungal diseases like anthracnose and host-specific rusts. They often start along the mid-vein of leaves, either near the center or toward the stem end. Fungal diseases are aggravated or initiated by humid conditions. Rusts can be treated early in the disease process, but good sanitation is vital to prevent it from spreading further. When tiny, rust-colored spots appear in the middle of your plant’s leaves, try neem oil before breaking out stronger chemicals like thiophanate methyl, myclobutanil or chlorothalonil. Remove any plants that resist treatment and keep all plant debris cleaned up off of the ground. Anthracnose also begins along the mid-vein in many plants, but is primarily a problem for woody plants, although tomatoes and other crops have been known to contract it. This fungus creates water-soaked lesions on leaves along the mid-vein that soon dry out and brown. Anthracnose is difficult to treat, but crop rotation and sanitation are the keys to preventing reinfection. A number of plant viruses result in vein necrosis, the death of the central leaf vein and those tissues surrounding it, causing browning. Other common symptoms include discolored spots, rings or bullseyes in a range of colors, general unthriftiness and distortion of emerging growth.
A plant affected by a virus cannot be cured, so it’s best to destroy them before other plants are infected as well. Many viruses are vectored by small, sap-sucking insects; be on the lookout for pests in and around sick plants.
Causes for Plants Going Brown in Center Crown and Root Rot The center rotting out of a plant is almost always related to crown or root rot. Most plants can’t tolerate a soggy environment, especially those with crowns densely covered with leaves, like African violets. When you keep the soil wet all the time, fungal pathogens take advantage of the humidity that develops under the leaves of these low-growing plants, reproducing rapidly. Both root and crown rot can appear similar in these short plants, with the plants going brown in the center as the disease progresses. If you’re asking yourself, “What is causing brown leaves in center of my plant,” you need to check the soil moisture first. Allow the top inch or two of soil to dry between waterings and never leave plants soaking in water-filled saucers. Plants with root rot may be saved if you catch it in an early stage. Dig your plant, trim out any brown, black or soggy roots and replant into a well-draining medium — chemicals won’t help, the only thing that will fix root rot is a drier environment.
Diseases That Cause Brown Leaves Other reasons why leaves turn brown in middle include fungal diseases like anthracnose and host-specific rusts. They often start along the mid-vein of leaves, either near the center or toward the stem end. Fungal diseases are aggravated or initiated by humid conditions. Rusts can be treated early in the disease process, but good sanitation is vital to prevent it from spreading further. When tiny, rust-colored spots appear in the middle of your plant’s leaves, try neem oil before breaking out stronger chemicals like thiophanate methyl, myclobutanil or chlorothalonil. Remove any plants that resist treatment and keep all plant debris cleaned up off of the ground. Anthracnose also begins along the mid-vein in many plants, but is primarily a problem for woody plants, although tomatoes and other crops have been known to contract it. This fungus creates water-soaked lesions on leaves along the mid-vein that soon dry out and brown. Anthracnose is difficult to treat, but crop rotation and sanitation are the keys to preventing reinfection. A number of plant viruses result in vein necrosis, the death of the central leaf vein and those tissues surrounding it, causing browning. Other common symptoms include discolored spots, rings or bullseyes in a range of colors, general unthriftiness and distortion of emerging growth.
A plant affected by a virus cannot be cured, so it’s best to destroy them before other plants are infected as well. Many viruses are vectored by small, sap-sucking insects; be on the lookout for pests in and around sick plants.
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Dummer. ゛☀
2017年08月08日
As gardeners, we face a lot of hurdles when it comes to keeping our plants alive and healthy. If the soil’s wrong, the pH is off, there are too many bugs (or not enough bugs), or disease sets in, we’ve got to know what to do and do it right away. Bacterial or fungal diseases can be devastating, but they usually give us a fighting chance. Viroids and viruses are another story altogether. Impatiens necrotic spot virus (INSV) is one of the most common viruses in the plant world. It’s an intimidating diagnosis for your plants, but without understanding the disease, you’ll never be able to manage it properly. What is INSV? INSV is an aggressive plant virus that can quickly infect greenhouses and gardens, and is especially common in impatiens plants.
It results in total losses, since plants affected by impatiens necrotic spot virus are no longer marketable, cannot be used for seed-saving and can continue to spread the virus as long as they’re present. Impatiens necrotic spot virus symptoms are highly variable, a fact that often delays gardeners’ decision making about infected plants. They may develop yellow bull’s eye markings, stem lesions, black ring spots and other leaf lesions, or infected plants may simply struggle to thrive. Once you suspect impatiens necrotic spot, treatment won’t help – you must destroy the plant immediately. If many plants are infected, it’s a good idea to contact your university extension office for testing to confirm the virus is present.
What Causes Impatiens Necrotic Spot? Western flower thrips are the primary vector for INSV in the garden and greenhouse. These tiny insects spend most of their lives on or near the flowers of your plants, though you may never see them directly. If you’ve noticed black spots or areas where pollen is spread across the flower, western flower thrips may be to blame. Placing yellow or blue sticky cards throughout potentially infected areas are the best way to confirm your suspicions of an infestation. Having flower thrips is annoying, but if none of your plants are infected with INSV, they can’t transmit the disease on their own. This is why it’s so important to quarantine any new plants that come into close contact with your old plants.
You should also clean your tools thoroughly between plants, especially if you are concerned about INSV. It can easily be transmitted via plant fluids, like those found in the stems and branches. Unfortunately, there’s no easy answer for INSV. Practicing good tool hygiene, keeping thrips under control and removing suspect plants are the best ways to protect yourself from the heartbreak this disease brings with it.
It results in total losses, since plants affected by impatiens necrotic spot virus are no longer marketable, cannot be used for seed-saving and can continue to spread the virus as long as they’re present. Impatiens necrotic spot virus symptoms are highly variable, a fact that often delays gardeners’ decision making about infected plants. They may develop yellow bull’s eye markings, stem lesions, black ring spots and other leaf lesions, or infected plants may simply struggle to thrive. Once you suspect impatiens necrotic spot, treatment won’t help – you must destroy the plant immediately. If many plants are infected, it’s a good idea to contact your university extension office for testing to confirm the virus is present.
What Causes Impatiens Necrotic Spot? Western flower thrips are the primary vector for INSV in the garden and greenhouse. These tiny insects spend most of their lives on or near the flowers of your plants, though you may never see them directly. If you’ve noticed black spots or areas where pollen is spread across the flower, western flower thrips may be to blame. Placing yellow or blue sticky cards throughout potentially infected areas are the best way to confirm your suspicions of an infestation. Having flower thrips is annoying, but if none of your plants are infected with INSV, they can’t transmit the disease on their own. This is why it’s so important to quarantine any new plants that come into close contact with your old plants.
You should also clean your tools thoroughly between plants, especially if you are concerned about INSV. It can easily be transmitted via plant fluids, like those found in the stems and branches. Unfortunately, there’s no easy answer for INSV. Practicing good tool hygiene, keeping thrips under control and removing suspect plants are the best ways to protect yourself from the heartbreak this disease brings with it.
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Dummer. ゛☀
2017年08月08日
New growth on your plants is a promise of blooms, big beautiful leaves or, at the very least, an extended lifespan; but when that new growth is wilting or dying, most gardeners panic, not knowing what to do. Although dying growth on plants of any age is a serious and difficult problem to manage, there are a few things you can try to save your plants before they go belly up. Why New Growth is Dying Well, that’s really the question, isn’t it? The reasons for tender growth dying are numerous, but they can generally be divided into these categories: bugs, vascular disease and root damage. 
Pests – When you’re trying to determine how to fix dying growth, bugs are by far the easiest. Tip and twig borers, like those common on many evergreen trees and blueberries, prefer to burrow into the soft tissues at the end of shrubs and trees. Look for tiny holes at the end, or snap some dying tissue off and inspect it for galleries or tunnels. You may never see the tiny beetles responsible, but their telling tunnels and entry holes are evidence enough. Disease – Vascular diseases are caused by fungal and bacterial pathogens that invade the transport tissues of your plants. As these pathogens multiply, they clog the vascular tissues, making it difficult or impossible for some parts of your plant to get nutrients, water and send manufactured food back to the crown.
All this blockage will eventually cause the death of tissues, and tender new growth is usually the most susceptible since it’s the furthest from the roots. Root damage – Root damage is another common cause of dead new growth. Fertilizers are great and so is watering your plant, but there’s such a thing as too much. When this good stuff is in excess, it often leads to root damage. The smallest roots usually die first, but sometimes whole sections of the root system can be killed, especially in the case of excess slow-release fertilizer or fertilizer salt build-up. Fewer roots means fewer nutrients and less water that can be transported, so these valuable materials often doesn’t make it all the way to the tips of the plant once root damage is severe. How to Fix Dying Growth Dying growth can be difficult to cure, no matter the cause. If you’ve got boring beetles, they’ll probably be long gone before your plant starts to show signs of damage and vascular diseases are almost always death sentences, so intervention in either case is usually pointless. Damaged roots, on the other hand, can sometimes be regrown with careful management. If possible, dig your plant and check the roots.
You’ll need to prune out any that are black, brown or feel soft. Increase the drainage for outdoor plants by adding enough compost to fill the rootball’s hole one quarter to one half of the way. Potted plants will need to be flushed, do this by removing their saucers and watering the plant from the top, until the water runs out the bottom. Repeat this four times to remove excess fertilizer salts from the soil. If the soil stays soggy for more than a few minutes, you should consider repotting the plant. Going forward, pay close attention to how often you fertilize and water your plant. Remember, too much is just as bad for them as too little. Water only when the plant’s soil surface feels dry, and fertilize only when the plant appears to need it, such as when the leaves start to lighten in color. Never leave your plant in standing water, as this will only undo the work you’ve done to help save it.
Pests – When you’re trying to determine how to fix dying growth, bugs are by far the easiest. Tip and twig borers, like those common on many evergreen trees and blueberries, prefer to burrow into the soft tissues at the end of shrubs and trees. Look for tiny holes at the end, or snap some dying tissue off and inspect it for galleries or tunnels. You may never see the tiny beetles responsible, but their telling tunnels and entry holes are evidence enough. Disease – Vascular diseases are caused by fungal and bacterial pathogens that invade the transport tissues of your plants. As these pathogens multiply, they clog the vascular tissues, making it difficult or impossible for some parts of your plant to get nutrients, water and send manufactured food back to the crown.
All this blockage will eventually cause the death of tissues, and tender new growth is usually the most susceptible since it’s the furthest from the roots. Root damage – Root damage is another common cause of dead new growth. Fertilizers are great and so is watering your plant, but there’s such a thing as too much. When this good stuff is in excess, it often leads to root damage. The smallest roots usually die first, but sometimes whole sections of the root system can be killed, especially in the case of excess slow-release fertilizer or fertilizer salt build-up. Fewer roots means fewer nutrients and less water that can be transported, so these valuable materials often doesn’t make it all the way to the tips of the plant once root damage is severe. How to Fix Dying Growth Dying growth can be difficult to cure, no matter the cause. If you’ve got boring beetles, they’ll probably be long gone before your plant starts to show signs of damage and vascular diseases are almost always death sentences, so intervention in either case is usually pointless. Damaged roots, on the other hand, can sometimes be regrown with careful management. If possible, dig your plant and check the roots.
You’ll need to prune out any that are black, brown or feel soft. Increase the drainage for outdoor plants by adding enough compost to fill the rootball’s hole one quarter to one half of the way. Potted plants will need to be flushed, do this by removing their saucers and watering the plant from the top, until the water runs out the bottom. Repeat this four times to remove excess fertilizer salts from the soil. If the soil stays soggy for more than a few minutes, you should consider repotting the plant. Going forward, pay close attention to how often you fertilize and water your plant. Remember, too much is just as bad for them as too little. Water only when the plant’s soil surface feels dry, and fertilize only when the plant appears to need it, such as when the leaves start to lighten in color. Never leave your plant in standing water, as this will only undo the work you’ve done to help save it.
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Dummer. ゛☀
2017年08月08日
When black spores appear on your lawn or garden plants, it’s understandably frustrating -after all, you’ve given those plants lots of tender care and they’re sick despite your efforts. Try not to panic, we’ve got lots of information about treating black smut fungus, a common cause of black spores on turfgrass, small grains and ornamentals. What is Black Smut Fungus? Fungal diseases can be the most frustrating to deal with and they seem to spring up out of nowhere and disappear with the same level of mystery. Although black smut is a minor disease in most parts of the country, it’s important to know how to handle it when your lawn or garden suddenly develops a load of black spores.
Black smut is a fungal disease that appears on small grains, grasses, onions and even herbaceous ornamentals under the right conditions. Unlike many fungal diseases, though, plants affected by smut may live many years before they begin to show signs of the disease. Turf grasses, for example, often don’t look sick until three or four years after their initial infection. Although signs of smut will vary based on the species of smut and the host, common smut fungus symptoms include galls or boils that enlarge any above-ground plant tissues, yellow striping on leaves or a powdery brown or black material on plant parts. The black or brown powder is actually a fine covering of reproductive spores and will occur late in the disease process.
Smut Fungus Control Because smut spores are spread by wind and splashing water, it can be difficult to stop the problem at the source. Instead, treating black smut fungus has to focus on creating an unfriendly environment for the spores. When the outdoor temperatures rise above 60 degrees Fahrenheit (15 C.), it may seem like your smut problem is defeated, but it’s hard to kill the disease completely since the fungus resides in the growing points of the plant. On a lawn, an infection of smut can be tolerated provided that you’re overseeding with a more resistant grass species, such as the Kentucky bluegrass. Most importantly, you’ll have to carefully monitor your fertilization practices, as smut thrives in a high nitrogen environment.
Switch to a balanced fertilizer, such as a 10-10-10, and only apply it in the fall, after the smut pathogen is dormant. Keeping your plants healthy will help them resist a smut infection, but if the disease is very severe in valuable plants, you may consider applying a fungicide. Demethylase inhibitors are very effective when applied in the spring at the label rates. Remember, fungicides are always a last resort option, as most fungal issues can be corrected by modifying the environment.
Black smut is a fungal disease that appears on small grains, grasses, onions and even herbaceous ornamentals under the right conditions. Unlike many fungal diseases, though, plants affected by smut may live many years before they begin to show signs of the disease. Turf grasses, for example, often don’t look sick until three or four years after their initial infection. Although signs of smut will vary based on the species of smut and the host, common smut fungus symptoms include galls or boils that enlarge any above-ground plant tissues, yellow striping on leaves or a powdery brown or black material on plant parts. The black or brown powder is actually a fine covering of reproductive spores and will occur late in the disease process.
Smut Fungus Control Because smut spores are spread by wind and splashing water, it can be difficult to stop the problem at the source. Instead, treating black smut fungus has to focus on creating an unfriendly environment for the spores. When the outdoor temperatures rise above 60 degrees Fahrenheit (15 C.), it may seem like your smut problem is defeated, but it’s hard to kill the disease completely since the fungus resides in the growing points of the plant. On a lawn, an infection of smut can be tolerated provided that you’re overseeding with a more resistant grass species, such as the Kentucky bluegrass. Most importantly, you’ll have to carefully monitor your fertilization practices, as smut thrives in a high nitrogen environment.
Switch to a balanced fertilizer, such as a 10-10-10, and only apply it in the fall, after the smut pathogen is dormant. Keeping your plants healthy will help them resist a smut infection, but if the disease is very severe in valuable plants, you may consider applying a fungicide. Demethylase inhibitors are very effective when applied in the spring at the label rates. Remember, fungicides are always a last resort option, as most fungal issues can be corrected by modifying the environment.
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