Thrips are small (1/5th inch), fringe-winged, pale-colored insects. Normally, they are responsible for negligible problems on houseplants, but plants in the Gesneriaceae family (African violet) and Commelinaceae family (Wandering Jew) are prone to attack.[图片]Symptoms and Diagnosis Thrips are rarely seen because of their small size. The insects feed by puncturing the surface of the plant parts with their single large mandible and slurping the plant juices that seep from the wound. Flowers or leaves may develop silvery streaks. Heavily infested leaves appear brownish or silvery, and growing points may become contorted. Some species of thrips leave sooty spots of black fecal matter on the leaves. Thrips also vector plant diseases. Light blue cards coated with a thin film of oil suspended within two feet above indoor plants can be used as indicator traps. Winged adults caught on the card indicate the presence of thrips.[图片]Life Cycle Female thrips lay their eggs in tiny slits cut into the surface of leaves, flowers, and stems. The eggs can be laid any time of year and hatch within a few days in warm, indoor conditions. The young, called nymphs, are cream to pale green and only visible with magnification. They feed for 7–14 days. Fullgrown nymphs, in most species, drop off the plant to the soil where they burrow down and pupate. Winged adults emerge to complete the cycle. Integrated Pest Management Strategies 1. Keep plants moist. Plants that are kept too dry are more likely to be damaged by thrips. To limit damage or reduce future damage after other initial control measures are used, keep plants moist and increase humidity.[图片]2. Insecticidal soap. Insecticidal soaps, which are considered nontoxic to humans and pets, give good control. Be sure that flowers and growing tips are well covered with the spray. Frequent sprays may be needed until the problem is under control. 3. Use superior horticultural oil sprays. Highly refined oils sold as superior or horticultural oils will also control thrips. The oil suffocates the insects. These oils are highly refined and under proper conditions, can be applied to plants in foliage without damage. Follow label directions to avoid damage to some plants that may be sensitive. Superior oils are also considered nontoxic and are less likely to harm beneficial insects. When spraying indoors, protect surfaces that may be damaged by an oil residue.[图片]4. Use chemical insecticides. Many insecticides registered for use indoors are available. Sprays containing pyrethrins, a plant-derived insecticide, are effective and more benign than other chemical pesticides. Follow label directions and, if possible, spray out-of-doors or in a garage, weather permitting. 5. To limit future problems, inspect plants regularly. With regular inspection, pest problems can be caught when just beginning and control is easier. It is also recommended to isolate newly acquired plants for 2–3 weeks to limit introducing pests indoors. Bringing plants indoors in the fall is another way of introducing insects indoors.

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Spider mites are spiders, not insects. They have 8 legs; insects have only 6. Regardless, they are a serious pest both indoors and out. Spider mites are very small, only about 1/50 of an inch long, and so are difficult to see. They have piercing-sucking mouth parts for feeding on plant sap. They can multiply rapidly and in large numbers, cause leaves to take on a dusty, dull appearance. Leaves then yellow and drop or turn brown or tan.[图片]Symptoms and Diagnosis Since the mites are so small, the first sign is generally a plant that looks dull or in poor health. Leaves may appear stippled and curled. Fine webbing may also be evident under the leaves or between the leaf and the stem. When a leaf or branch is tapped over a white sheet of paper, small specks that appear as dust or pepper may be seen to move. Life Cycle Spider mites can go from egg to mature adult in less than two weeks. Indoors as well as outdoors, several generations occur each year.[图片]Integrated Pest Management Strategies 1. Remove mites. Dislodge as many mites as possible using a strong stream of water. Done on a regular basis, this can reduce populations dramatically. Wash the plants either outdoors or in the shower. Protect the soil so it is not washed out of the pot by the spray. 2. Use insecticidal soap. Many insecticidal soaps are also effective in controlling mites so check the label. Other soap products may actually be labeled as miticidal sprays. These soaps are specially formulated to kill mites and not damage plants. They can be very effective if used frequently until the problem is under control.[图片]3. Use superior horticultural oil sprays. Highly refined oils sold as superior or horticultural oils are also very effective in controlling mites. The oil suffocates the mites. Unlike dormant oils, these oils are highly refined and under proper conditions, can be applied to plants in foliage without damage. Follow label directions to avoid damage to some plants that may be sensitive. Superior oils are also considered nontoxic and are less harmful to beneficial insects. When spraying indoors, protect surfaces that may be damaged by an oil residue. 4. Use chemical miticides. Many miticides registered for use indoors are available. Follow directions and if possible, spray out-of-doors or in a garage, weather permitting. Check label for control of spider mites.[图片]5. To limit future problems, inspect plants regularly. With regular inspection, pest problems can be caught when just beginning and control is easier. It is also recommended to isolate newly acquired plants for 2–3 weeks to limit introducing pests indoors. Bringing plants indoors in the fall is another way of introducing mites indoors.

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Scale insects are small, piercing-sucking insects that often go unnoticed on indoor plants. The adult forms can be attached to leaves, petioles, and stems. They suck plant juices and can cause plants to lose vigor.[图片]Symptoms and Diagnosis Since the insects are often overlooked, the first signs may be yellowing or wilting leaves that may eventually drop. Leaves may also be covered with a clear sticky substance called honeydew. Honeydew is the insects’ excrement consisting of partially digested sap and may coat the floor and other objects beneath the plant as it spatters down from above. A sticky floor beneath a susceptible plant is a telltale sign that infestation is underway. Under humid conditions, a black mold, called sooty mold, may grow on the honeydew making the leaves look dirty. Closer inspection will reveal small cottony or dome-shaped shells attached to stems and leaves. When pried off with a knifepoint, they may be hollow underneath or house adults and/or eggs. Scale can be differentiated from parts of the plant by scraping. If the structure is green when scraped or cannot be pried off, it is more than likely part of the plant.[图片]Life Cycle Scale insects have a simple life cycle of egg, nymph (crawler), and adult. Indoors, eggs can be laid any time under the protective shell. The eggs hatch and the crawlers seek out new feeding sites. This crawler stage is when scale is easiest to control. When the crawlers settle, they insert their mouth parts into the plant and begin feeding on the plant's sap. The protective shell develops soon after feeding begins and the insect loses use of its legs. Indoor scales can go through many generations a year.[图片]Integrated Pest Management Strategies 1. Remove insects by hand. If caught early, scale insects can be rubbed off by hand, with a discarded toothbrush, or with a cotton swab soaked in isopropyl alcohol. Prune out heavily infested portions of the plant. 2. Use insecticidal soap. Monitor plants frequently. When crawlers are noticed, use insecticidal soaps that are formulated to kill insects and not damage plants. Frequent sprays may be needed until the problem is under control.[图片]3. Use superior horticultural oil sprays. Highly refined oils sold as superior or ultra-refined horticultural oils are effective in controlling both adults and scale crawlers. The oil suffocates the insects. Unlike dormant oils, these oils are highly refined and under proper conditions, can be applied to plants in foliage without damage. Follow label directions to avoid damage to certain plants that may be sensitive. Superior oils are also considered nontoxic and are less likely to harm beneficial insects. When spraying indoors, protect surfaces that may be damaged by an oil residue. 4. Use chemical insecticides. Many insecticides registered for use indoors are available. Sprays containing pyrethrins, a plant-derived insecticide, are effective and more benign than other chemical pesticides. Follow label directions and, if possible, spray out-of-doors or in a garage, weather permitting.[图片]5. To limit future problems, inspect plants regularly. With regular inspection, pest problems can be caught when just beginning and control is easier. It is also recommended to isolate newly acquired plants for 2–3 weeks to limit introducing pests indoors. Bringing plants indoors in the fall is another way of introducing insects indoors. Infested houseplants summered outdoors frequently benefit from the many natural enemies of scale. Be sure to check plants thoroughly before bringing them indoors in fall to be sure they are pest-free.

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Although most problems associated with cacti and succulents grown as houseplants are bacterial or fungal diseases caused by overwatering, they do get the occasional insect pest. The most common pests are scale, mealy bugs and root mealy bugs. Less common pests include spider mites and fungus gnats. Control of these pests is difficult because they are small and hide in places that make them hard to see, because they have a cottony or hard covering to protect them or because they have developed a resistance to insecticides.[图片]Symptoms and Diagnosis Mealybugs and scale both damage plants by sucking plant juices resulting in plants that are weak with wrinkled, shriveled leaves. Severe infestations may result in the death of the plant. Often the first symptom of a problem is stickiness or black mold on or near the plant. More careful examination will reveal the actual insect. Scale insects resemble small cottony or dome-shaped shells. They are attached to stems and leaves but can be scraped or pried off.[图片]Mealybugs are 1/5 to 1/3 inch long, and have a waxy, white, cottony appearance. They are slow moving and usually are in clusters along leaf veins or spines, on the underside of leaves, and in hidden areas at joints. Root mealy bugs live in the soil and look like white deposits on the roots. In addition to the damage caused by sucking juices from the roots, root mealy bugs make the plant more susceptible to rot from bacterial and fungal infections. Fungus gnats are 1/8 to 1/16-inch long black flies that resemble mosquitoes. They are most often seen hovering above the soil surface. Adult flies do not cause any damage but the larva live in the soil consuming organic matter and roots. Large plants are usually not affected by the root damage but seedlings may be stunted or killed.[图片]Spider mites also damage cacti and succulents by sucking the plant’s juices. The first sign of spider mites is usually webbing and small brown dots, especially on younger growth, where the plant's epidermis has been damaged. Spider mites are very small, only about 1/50 of an inch long, and will look like dust when the affected area is tapped over a piece of paper. Life Cycle Consult the following IPM pages for detailed information on the life cycle of these pests: Mealybugs, Scale, Spider mites and Fungus gnats.[图片]Integrated Pest Management Strategies 1. Practice good cultural techniques. A healthy plant is better able to overcome insect damage. Be sure to grow your cacti and succulents in the conditions recommended for the species including proper sunlight, water and drainage. Practice good hygiene by keeping the pots free of dead leaves and spent flowers. 2. Quarantine new plants. To ensure that you do not introduce pests to your healthy plants, check new plants carefully and quarantine them until you are sure they are pest-free. If you do find pests on new plants, treat the problem immediately or discard the plant.[图片]3. Wash mealybugs and spider mites off the plant with a strong stream of water. Cover the soil in the pot to prevent overwatering or to keep the soil from washing away. Spider mites are most troublesome in spots with low humidity and poor ventilation. Root mealy bugs may also be washed away if they are noticed on the roots when repotting the plant. 4. Remove mealybugs and scale using cotton swabs dipped in alcohol. Spraying the plant with a dilute alcohol solution (1:3) may help control pests that are not easily visible but the solution may damage the epidermis of sensitive cacti and succulents. Test a small area before spraying the entire plant. 5. Use yellow sticky traps to control adult fungus gnats.[图片]6. Use insecticidal soap but be aware that it may damage some plants. Cacti have oils and waxes that may make them susceptible to damage from the soap. Be sure to read the product’s label to see if it is safe for your plant. It is a good idea to test a small area of the plant before spraying the entire plant. 7. Use insecticides such as Neem or pyrethrins. Always check the label to be sure it is safe for your plant. 8. Use a systemic insecticide such as imidacloprid or acephate to control pests that are not easily accessible to sprays. Be sure to read the product’s label to see if it is safe for your plant.

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Mealybugs are common pests of indoor plants. They can also be serious pests of outdoor plants in warmer climates, such as Florida and California.[图片]Symptoms and Diagnosis Adult females are oval, 1/5 to 1/3 inch long, and have a waxy, white, cottony appearance. They are slow moving and usually are in clusters along leaf veins, on the underside of leaves, and in hidden areas at joints. They are piercing-sucking insects, which feed on plant sap. The insects exude a honeydew, which can cause leaves to become sticky. Ants may be attracted to the sweet liquid. In time, a black mold, called sooty mold, can grow on the honeydew giving the leaves a dirty, sooty appearance. Plants infested with mealybugs become weak, may wilt and turn yellow, and eventually die.[图片]Life Cycle Indoors, eggs can be laid any time of year. Eggs hatch in about 2 weeks. The young mature in 6–8 weeks. Several generations can occur in the same year. Integrated Pest Management Strategies 1. Remove insects. Dislodge as many insects as possible using a strong stream of water. A cotton swab soaked in rubbing alcohol will also effectively remove a few insects. 2. Use insecticidal soap. Insecticidal soaps specially formulated to kill insects and not damage plants are effective if used frequently until the problem is under control.[图片]3. Use superior oil sprays. Highly refined oils sold as superior or horticultural oils are also very effective in controlling mealybugs. The oil suffocates the insects. Unlike dormant oils, these oils are highly refined and under proper conditions, can be applied to plants in foliage without damage. Follow label directions to avoid damage to some plants that may be sensitive. Superior oils are also considered nontoxic and are less likely to harm beneficial insects. When spraying indoors, protect surfaces that may be damaged by an oil residue. 4. Use chemical insecticides. Many insecticides registered for use indoors are available. Follow directions and, if possible, spray out-of-doors or in a garage, weather permitting.[图片]5. To limit future problems, inspect plants regularly. With regular inspection, pest problems can be caught when just beginning and control is easier. It is also recommended to isolate newly acquired plants for 2–3 weeks to limit introducing pests indoors. Bringing plants indoors in the fall is another way of introducing insects indoors.

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分布与危害 #郁金香刺足根螨 刺足根螨别名球根粉螨、葱螨，是球根花卉的重要害虫。除为害郁金香外，还为害郁金香 、水仙、百合、菖兰、葱兰、风信子、苏铁等花卉。 该螨是以成、若螨刺吸球根鳞片及块根为害，受害鳞茎会有汁液流出的现象，表面变褐腐烂，肉质鳞片干缩，破裂成似木栓化的碎片。导致地上部植株矮小、瘦弱，花为畸形，且小，严重影响花卉的观赏价值。 形态特征 成螨 雌螨体长0.58-0.87毫米，卵圆形，白色发亮。螯肢和附肢浅褐色；前足体板近长方形；后缘不平直；基节上毛粗大，马刀形。格氏器官末端分叉。 足短粗，跗节Ⅰ、Ⅱ有一根背毛呈圆锥形刺状。雄螨体长0.57- O.8毫米。体色和特征相似于雌螨，阳茎呈圆筒形。跗节爪大而粗，基部有一根圆锥形刺。 卵 长0.2毫米，椭圆形，乳白色半透明。 若螨 体长0.2-0.3毫米，体形与成螨相似，颗体和足色浅，胴体呈白色。 发生规律 该螨年发生9-18代，主要是以成螨在病部及土壤中越冬，尤其是腐烂的鳞茎残瓣中最多，两性生殖。该螨喜高温高湿的环境，在适宜的条件下繁殖快。雌螨交配后1-3天开始产卵，卵期3-5天。1龄和3龄若螨期，遇到不适条件时，出现体形变小的活动化播体。若螨和成螨开始多在块根周围活动为害，当鳞茎腐烂便集中于腐烂处取食。该螨既有寄生性也有腐生性，有很强的携带腐烂病菌和镰刀菌的能力。高温高湿干旱对其生存繁殖不利。在16℃至26℃和高湿下活动最强，造成的伤口为真菌、细菌和其他有害生物侵入提供了条件。 防治方法 1、加强栽培管理，高温季节深耕暴晒，消灭大量根螨，栽种前对土壤严格消毒。 2、不宜连作，可减少虫源。 3、种植前可对鳞茎进行挑选，选择无虫的鳞茎种植。 4、对鳞茎进行消毒，可用国光红杀（10%苯丁.哒）1000倍液+国光乐克（5.7%甲维盐）3000倍液对鳞茎进行喷雾，或将被害鳞茎放在稀石灰水中浸泡10分钟，取出冲洗干净，阴干后使用。

分布与危害 危害红花蕉的#蕉苞虫 为香蕉卷叶虫，又名香蕉弄蝶。危害时，其幼虫将叶卷成苞，取食叶片。发生严重时叶苞累累，蕉叶残缺，不仅影响植株正常生长，而且减少花茎产量，降低观赏价值。 形态特征 发生规律 蕉苞虫在南方地区或棚室内1年发生4代，以老熟幼虫在叶苞中越冬，成虫于春季出现。成虫在清晨和傍晚活动，飞翔迅速。卵散产于寄主叶片、嫩茎和叶柄，以8～9月危害最严重。 防治方法 ①清除枯叶残株，集中烧毁，在幼虫初发生时，及时摘除虫苞，杀死其中虫体； ②注意保护天敌赤眼蜂； ③在幼虫初发生时，用90％敌百虫原药800倍液进行喷杀。

分布与危害 #白星花金龟 Postosia brevitarsis Lewis又名白纹铜花金龟、白星花潜。属鞘翅目花金龟科。分布全国。为害鸡冠花、蔷薇、蜀葵、秋葵、菊花、大花萱草、美人蕉、金叶女贞、樱桃、葡萄。成虫不仅咬花卉叶、芽、花冠，还群食果实，造成谢花落果，尤其喜欢吃腐烂的果实。 形态特征 成虫体长22毫米，宽12毫米左右。体黑紫铜色，有金属色泽。体宽背平，鞘翅上有白色斑纹。臀板有绒斑6个，外露。幼虫俗称蛴螬，体长约30毫米，乳白色。 发生规律 1年发生1代，以幼虫在腐殖质土和厩肥堆中越冬。翌年4～6月幼虫断断续续老熟，在20厘米左右土层中化蛹，蛹期约20多天。6～10月为成虫期，6～7月为盛发期，对果汁和糖醋液有趋性，有假死性，受惊动后，飞走或掉落。成虫白天为害花冠使花朵谢落。7月逐渐转到果实上为害，造成果实坑疤或腐落。成虫产卵于土中，卵期约为10天。孵化后的幼虫在土中和堆肥料中栖息，取食腐殖质，秋天后寻找合适场所在土中越冬。 防治方法 （1）消灭虫源。改变花卉栽培技术;田间不堆放粪肥与垃圾等。 （2）药剂防治。根灌50％辛硫磷1000倍液，此药严禁叶面喷施。 （3）保护和利用天敌。如白僵菌、绿僵菌、土蜂。

相关图片 [图片][图片][图片][图片]#月季白轮盾蚧 分布与危害 月季白轮盾蚧学名Aulacaspis rosarum Borch.，别名月季白轮蚧、拟蔷薇白轮蚧，属同翅目,盾蚧科。除危害月季外，还危害蔷薇、玫瑰、黄刺梅、苏铁等。分布在上海、江苏、浙江、江西、福建、四川、云南、广西、北京、安徽等地。 以若虫和雌成虫固着在枝干上吸取汁液为害，被害部变为褐色，发生严重时，整个枝干布满蚧体，树势衰弱，植株抽条，甚至枯死。 形态特征 成虫 雌虫直径2.0-2.4毫米。初为黄色，后变为橙色，介壳灰白色，近圆形，两个壳点，第一壳点淡褐色，靠近介壳边缘，叠于第二壳点之上；第二壳点黑褐色，近介壳中心。雄成虫体长为1.2毫米，宽1.0毫米，头胸部膨大，头缘突明显，中胸处较宽。后胸和臀前腹节侧缘呈瓣状突出，初期橙黄色，后期紫红色。臀叶3对，中叶位于臀板凹缺处，基部轭连，内缘基部直，端半部向外倾斜；背腺管5列，第2-4腹节亚中群均为前后2排。围阴腺5群。雄介壳长0.8毫米，宽0.3毫米，白色，蜡质，两侧近平行，背面有3条纵背线，壳点位于前端。 卵长径约0.16毫米，紫红色，长椭圆形。 若虫 初龄若虫，体橙红色，椭圆形。其上分泌有白色蜡丝。触角5节，端节最长。腹末有l对长毛。 发生规律 年发生2-3代，因地制宜，在华北地区年发生2代，以受精雌成虫和2龄若虫枝干处越冬。翌年4月上中旬开始活动，一般将卵产于壳下，孵化盛期在5月上中旬和8月中下旬。成虫、若虫常群集于2年生以上枝干或皮层裂缝处危害，发生严重时可被一层白色絮状物。若虫孵化后从介壳下爬出并在枝干上缓慢爬行，蜕皮后固定危害。有世代重叠现象。 防治方法 （1）月季休眠期，剪除受害枝叶并集中深埋，喷施波美5度石灰硫磺合剂。 （2）结合修剪等管理，及时严重的。 （3） 选择对症药剂：刺吸式口器，应选内吸性药剂，背覆厚厚蚧壳（铠甲），应选用渗透性强的药剂如40%啶虫.毒（国光必治）1500-2000倍液喷雾防治，或用国光必治1500-2000倍+5.7%甲维盐乳油（ 国光乐克）2000倍混合液防治效果更佳。建议连用2次，间隔7-10天。

Powdery mildew is a common fungal disease of indoor plants. African violets, begonias, ivy, jade, kalanchoe, poinsettia and rosemary are susceptible to powdery mildew. It thrives best in cool, damp conditions.[图片]Symptoms and Diagnosis Powdery mildew starts as a dusty, white to gray, thread-like coating over leaf surfaces, stems, buds or flowers. It can be partially removed by rubbing the leaves but this will not eliminate the fungus. Life Cycle Powdery mildew is caused by many species of fungi each responsible for causing the disease on a limited number of plant species. That is, the species of fungi that causes powdery mildew on African violets is not the same species that causes powder mildew on rosemary. Therefore, powdery mildew on one plant may not spread to a dissimilar plant. Even given this, both plants may develop powdery mildew from different species of fungi if favorable conditions exist for disease development. Several species of powdery mildew can be common both indoors and out.[图片]Powdery mildew starts as discrete, circular powdery white spots on leaves. It may also be on other above ground plant parts. The fungal mycelium grows and in time can cover large parts of the plant giving them a dusty, powdery, or silvery appearance. Powdery spores are produced that spread to other parts of the plant or related plants. The disease can develop and spread anytime the conditions for growth are favorable. Photosynthesis is impaired and growth may be stunted. Buds fail to mature. The plant declines in growth and vigor and eventually becomes unsightly.[图片]Integrated Pest Management 1. Don’t ask for a problem. Choose healthy plants and purchase mildew resistant cultivars if possible. 2. Sanitation. At the first sign of infection, isolate the plant. Remove and dispose of all infected plant parts. Discard severely infected plants. 3. Evaluate and modify the growth environment. Keep plants in a well-ventilated area and do not overcrowd. Improve air circulation around plants. Avoid wetting leaves when watering, do not water from above.[图片]4. Don’t over fertilize. Avoid high nitrogen fertilizers since powdery mildew attacks new succulent growth. 5. Treat with baking soda. Some gardeners recommend applying a baking soda solution to prevent the fungi from establishing. This changes the pH of the leaf surface. Test on a few leaves first as this may damage some plants. Some may feel this treatment may look as unsightly as the mildew disease itself. 6. Use a commercial fungicide. Valuable plants or crops may require the application of an appropriate fungicide labeled for indoor use, preferably one that is systemic. Be sure to read the label and follow directions.

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