动态第187页 - 绿手指 - 养花技巧、花生病了怎么办、花园打理和设计

2018年05月25日

Description: This perennial plant is 1-3' tall, branching occasionally in the upper half. The light green to reddish brown stems are usually glabrous; sometimes the central stem has sparse lines of hairs. The alternate leaves are up to 5" long and 3" across (excluding the petioles), becoming smaller as they ascend the stems; they are medium to dark green above and light to medium green below. The lower leaves are cordate, while the upper leaves are cordate-ovate or ovate; their margins are coarsely serrated. Leaf upper surfaces are glabrous, while their lower surfaces are either glabrous or there are hairs along the major veins. The narrow petioles of the leaves are about one-half to almost as long as their blades (up to 3½" in length); they are either unwinged or slightly winged, becoming shorter among the upper leaves. The upper stem terminates in a panicle of flowerheads about ½-1½' long. This panicle is longer than it is wide and it is more broad toward the bottom than the apex. When upper lateral stems are present, much smaller panicles may be produced. The central stalk, lateral branches, and peduncles of each panicle are light to medium green, terete, and glabrous to short-pubescent. Each small flowerhead is about ½" across, consisting of 7-15 ray florets that surround a similar number of disk florets. The petaloid rays of these flowerheads are lavender, light blue-violet, or less often white; they are linear-oblong in shape. The corollas of the disk florets are short-tubular in shape; these corollas are initially cream-colored or pale yellow, but they later become pale purple to reddish purple with age. The apices of these corollas are 5-lobed; these lobes are short and erect. The base of each flowerhead is surrounded by slender floral bracts (phyllaries) that overlap each other in several series. These scaly bracts are light green, except for diamond-shaped patches of dark green toward their tips; they are linear-lanceolate to narrowly lanceolate in shape and about 3-5 mm. in length. The peduncles of the flowerheads are short (less than ½" in length). Among the branches of each panicle, there are leafy bracts up to 1" long; they are elliptic or linear-oblong in shape. The blooming period occurs from late summer into the fall and lasts about 1-2 months. Afterwards, the florets are replaced by achenes with small tufts of white hair. Individual achenes are 2-3 mm. long and oblongoid-oblanceoloid in shape. The root system is fibrous and short-rhizomatous. This aster reproduces by reseeding itself and vegetatively through its rhizomes. [图片]Cultivation: The preference is light shade or partial sun, moist to dry-mesic conditions, and soil that contains loam, clay-loam, or some rocky material. Occasionally the foliage is affected by powdery mildew and other kinds of disease organisms during the fall. During hot dry weather, the lower leaves may wilt and fall off. Plant size is variable depending on the fertility of the soil and moisture conditions. Plants that are grown in shade will produce smaller panicles of flowers than those that are grown in more sunlight. Range & Habitat: The native Blue Wood Aster occurs occasionally in scattered counties across Illinois (see Distribution Map). It is more common in the northern half of the state than in the southern half. Habitats include moist to dry deciduous woodlands, woodland borders, areas adjacent to woodland paths, thinly wooded bluffs, shaded areas along streambanks, and rocky wooded slopes. Some disturbance is beneficial in heavily wooded areas if it reduces excessive shade from overhead canopy trees or excessive competition from shrubs. [图片]Faunal Associations: The nectar and pollen of the flowerheads attract many kinds of insects, including long-tongued bees, short-tongued bees, wasps, flies, butterflies, skippers, and beetles. Bees are particularly important pollinators of the flowers. Caterpillars of the butterflies Chlosyne nycteis (Silvery Checkerspot) and Phyciodes tharos (Pearl Crescent) feed on the foliage of asters (Symphyotrichum spp.), as do the caterpillars of many moth species (see Moth Table). Some moth caterpillars also feed on the flowers, developing seeds, stems, and roots. Other insects that feed on these plants include leaf beetles, the larvae of leaf-mining flies and fruit flies, plant bugs, stink bugs, lace bugs, aphids, and leafhoppers (see the Insect Table for a more complete listing of these species). Mammalian herbivores, including rabbits, groundhogs, deer, and livestock, browse on the foliage of asters occasionally. The Wild Turkey and Ruffed Grouse eat both the foliage and seeds to some extent. Photographic Location: A rocky woodland in west-central Indiana. The inflorescence is small because the photographed plant was growing in a dry upland area of a shady woodland. [图片]Comments: In Illinois, the Blue Wood Aster (Symphyotrichum cordifolium) often hybridizes with Arrow-Leaved Aster (Symphyotrichum sagittifolium) and Drummond's Aster (Symphyotrichum drummondii), which can make the identification of some field specimens from this aster complex very difficult. The Blue Wood Aster can be distinguished from both Arrow-Leaved Aster and Drummond's Aster by its narrow petioles; the petioles of the latter two species are conspicuously winged with narrow green margins. Unlike Drummond's Aster, the Blue Wood Aster has stems and leaf undersides that are hairless or they have lines of hair; the stems and leaf undersides of Drummond's Aster are evenly pubescent. Some authorities consider the preceding species of asters to be varieties of each other, in which case the Blue Wood Aster is the typical variety, Symphyotrichum cordifolium cordifolium. Another woodland species, Short's Aster (Symphyotrichum shortii), is also similar to Blue Wood Aster in appearance, but Short's Aster has larger flowerheads (¾–1" across) and its leaves are smooth to slightly serrated along their margins. Another common name of Symphyotrichum cordifolium is Heart-Leaved Aster. A scientific synonym of this aster is Aster cordifolius.

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Miss Chen

2018年05月25日

Description: This herbaceous perennial plant is 1-1½' tall, consisting of both basal leaves and a flowering stem with a pair of opposite leaves. The erect to ascending stem is light green, terete, and conspicuously hairy. Both types of leaves are up to 6" long and 4" across (excluding the petioles); they are bipinnatifid, consisting of 1-3 pairs of primary lateral lobes and a primary terminal lobe. The primary lateral lobes are up to 2" long and 1" across, while the primary terminal lobe is up to 2" long and 2" across. Both types of lobes have shallow to moderately deep secondary lobes with rounded tips. For mature leaves, the upper leaf surface is yellowish green to dark green and glabrous, while the lower leaf surface is pale green and pubescent to hairy. Immature leaves may have short appressed hairs on their upper surfaces. The petioles of the leaves are up to 4" long and sparsely hairy. There is little difference in the appearance of the basal and opposite leaves, although the latter have shorter petioles. The foliage contains a yellow-orange sap. The upper stem terminates in either an individual flower or an umbel of 2-4 flowers. Each flower is about 1¼-2¼" across, consisting of 4 yellow petals, 2 early-deciduous sepals, numerous stamens with golden yellow anthers, and a pistil with a single stout style and knobby stigma. The petals are orbicular-obovate in shape, while the sepals are light green and very hairy. The ovary of the pistil is ¼-½" in length, narrowly ovoid in shape, more or less yellow, and finely hairy. The pedicels are ¼-2" long, light green, hairy, and terete; they are ascending to erect while the flowers are in bloom. The blooming period occurs from mid- to late spring, lasting about 2-3 weeks. In the absence of insect pollination, the flowers can self-pollinate. Shortly afterward, the flowers are replaced by ovoid seed capsules about ¾-1" long that nod from their pedicels; these capsules are 4-segmented and densely hairy. Numerous seeds are released after each capsule splits apart. They are dark brown and about 1.5 mm. in diameter; there is a white fringe of oil bodies (elaisomes) along one side of each seed. The root system consists of a woody caudex with coarse fibrous roots. [图片]Cultivation: The Celandine Poppy should be grown in dappled sunlight underneath a tree, or along the foundation of a building in partial shade. It adapts best to rich loamy soil and moist to mesic conditions. Most vegetative growth and development occurs during the spring before the trees fully leaf out. This plant adapts to flower gardens readily. Range & Habitat: The native Celandine Poppy is an uncommon plant that occurs primarily in southern Illinois; it has also been observed in Vermilion and Cook counties further to the north (see Distribution Map). Habitats include mesic deciduous woodlands, lower slopes of ravines, bases and lower slopes of bluffs, and rocky banks of streams. The Celandine Poppy is found in high quality woodlands; it is one of the woodland wildflowers that is threatened by the invasion of Alliaria petiolata (Garlic Mustard) and Microstegium vimineum (Japanese Stiltgrass). [图片]Faunal Associations: Little is known about the floral-faunal relationships for this species. The flowers provide only pollen as a reward to floral visitors. MacRae (1991) has observed adults of some metallic wood-boring beetles (Acmaeodera spp.) visiting the flowers. It is also likely that the flowers are visited by various bees and flies. The seeds are distributed to new locations by ants, which are attracted to their oily appendages (elaisomes). Woodland mice eat the seeds. The toxic foliage is avoided by mammalian herbivores. Photographic Location: A flower garden in Urbana, Illinois. [图片]Comments: The Celandine Poppy has attractive flowers and foliage. It resembles another species of the Poppy family, Celandine (Chelidonium majus), but the latter has yellow flowers that are smaller in size (¾" across or less) and its seed capsules are hairless, narrowly cylindrical, and erect. Celandine is a somewhat weedy species that was introduced from Europe; it is a biennial that blooms during the summer. Other species of the Poppy family in Illinois have flowers that are white, pink, orange-red, or purplish red. Most of these species have been introduced from Eurasia, although one of them, Bloodroot (Sanguinaria canadensis) is native to Illinois. Another common name of Stylophorum diphyllum is the Wood Poppy.

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Miss Chen

2018年05月25日

Description: This perennial wildflower is about 6-12" tall and unbranched, or sparingly so. Both fertile and infertile shoots are produced; the latter develop later in the year and don't produce flowers. The central stem is light green to pale purplish green and glabrous to moderately pubescent. The opposite leaves are up to 3" long and 1¼" across; they are ovate, lanceolate, oblanceolate, elliptic, or broadly oblong. The upper surface of these leaves is medium to dark green and finely pubescent (sometimes sparsely); their margins are smooth (entire) and ciliate. The leaf bases are sessile or nearly sessile, while their tips are either acute or blunt; lower leaves are more likely to have short petioles and blunt tips than upper leaves. The central stem of each fertile shoot produces a terminal cyme of flowers; occasional individual flowers may develop from the axils of the upper leaves. Each flower is about ½" across, consisting of 5 green sepals, 5 white petals (looking like 10 petals, because each petal is deeply bifurcated), a white ovary with 3 styles at its apex, and 10 stamens with reddish brown anthers. The petals are about the same length or a little longer than the sepals. Each sepal is lanceolate to ovate and pubescent. The pedicel of each flower is up to 1" long and pubescent. The blooming period occurs from mid- to late spring and lasts about a month. Each flower is replaced by an ovoid capsule that is open at its apex; it has 6 curved teeth around its upper rim. Each capsule contains many small seeds that are globoid, somewhat flattened, and minutely warty. Each seed is often slightly notched on one side. The root system consists of a taproot with slender fibrous roots. Small colonies of plants are occasionally formed. [图片]Cultivation: The preference is dappled sunlight to light shade during the spring, followed by light to medium shade. The soil should be well-drained but consistently moist, with an abundance of organic matter and a layer of decaying leaves. It should also be somewhat acidic. Shallow rocky ground and slopes help to reduce competition from taller plants. Range & Habitat: The native Star Chickweed is a rare plant in Illinois, where it is state-listed as 'endangered.' It has been found in Pope County of southern Illinois, and a few counties in NE Illinois (see Distribution Map). Illinois lies at the NW corner of the range for this species. It is more common in the southern half of Indiana and other states. Habitats include edges of rocky meadows, rocky wooded slopes, wooded bluffs, and the upper slopes of sandstone ravines. Outside of Illinois, another typical habitat is rich mesic woodlands. This conservative species is found in high quality woodlands, especially where sandstone is close to the ground surface. [图片]Faunal Associations: The flowers of Star Chickweed attract cuckoo bees (Nomada spp.), mason bees (Osmia spp.), Halictid bees (Augochlorella spp., Lasioglossum spp.), Andrenid bees (Andrena spp.), the Giant Bee Fly (Bombylius major), Syrphid flies, and other miscellaneous flies. Butterflies and skippers are rare visitors of the flowers. These insects are attracted primarily to the nectar of the flowers, although some of the bees collect pollen for their larvae and some of the flies feed on pollen as adults. Insects that feed on Stellaria spp., including possibly this chickweed, are the aphid Abstrusomyzus phloxae, the Pale Tortoise Beetle (Cassida flaveola), and caterpillars of a moth, Lobocleta ossularia (Drab Brown Wave). Information about this chickweed's ecological relationships with vertebrate animals is currently unavailable. Photographic Location: The edge of a rocky meadow and the wooded upper slope of a sandstone ravine at Shades State Park in west-central Indiana. [图片]Comments: Of all the chickweeds (whether native or introduced), Star Chickweed is arguably the most attractive. It's a pity that this species isn't more common in Illinois. The only other chickweed in Illinois that resembles it is Myosoton aquaticum (Water Chickweed), which is native to Eurasia. This latter species can become larger in size than Star Chickweed, and its leaves are usually more broad toward their bases. Even more importantly, the flowers of Water Chickweed have 5 styles and its seed capsules have 5 teeth. In contrast, Star Chickweed has flowers with 3 styles and seed capsules with 6 teeth. Water Chickweed, as its common name suggests, also prefers damp water-logged habitats, such as roadside ditches and low areas along rivers. Other common names of Stellaria pubera are Giant Chickweed and Great Chickweed; these names sometimes refer to Myosoton aquaticum as well.

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Miss Chen

2018年05月25日

Spike of FlowersDescription: This perennial wildflower is 3-12" tall, consisting of an unbranched flowering stalk, 1-2 basal leaves, and a few alternate leaves. Usually, individual plants are less than 7" tall. The basal leaves are 1-6" long and ¼-¾" across; they are lanceolate, oblanceolate, or elliptic in shape, while their margins are smooth. The alternate leaves are located along the lower half of the flowering stalk; they are often bladeless and sheath-like, but sometimes there are blades ¾-2½" long and about ¼" across. When alternate blades are present, they are narrowly lanceolate, oblanceolate, or elliptic, and their margins are smooth. Both basal and alternate leaves are medium to dark green and glabrous. The erect central stalk is medium to dark green, terete, and relatively narrow; it is glabrous below, becoming short-pubescent and glandular above. This stalk terminates in a spike of flowers about ¾-4" long. The flowers of each spike are densely arranged into 3-ranks (a double spiral). Each flower has 6 white tepals, a green ovary, and other reproductive organs. The tepals form a tubular corolla about 4-5 mm. long that is slightly curved and nodding. The corolla has an upper hood consisting of 3 fused tepals, a lower lip consisting of a single tepal, and 2 lateral tepals. As each flower develops, the lateral tepals become free toward the base and extend along the sides of the corolla. The lower lip extends to about the same length, or slightly beyond the hood. This lip is somewhat recurved, narrowly oval in shape, and its margins are slightly undulate and crisped. At the base of the lip, there is a pair of slender curved callosities (resembling minute claw-like extensions). The interior of the corolla is usually white, otherwise it is pale cream. The ovary is medium green, ovoid-oblongoid in shape, usually short-pubescent, and about 4-5 mm. long (although it becomes larger after the blooming period). Partially obscuring the ovary, there is a green bract (about 5-8 mm. in length) that is lanceolate-elliptic, short-pubescent, and glandular. The blooming period occurs during the early fall, sometimes extending into mid-fall. The flowers bloom from the bottom to the top of the raceme. Afterwards, the seed capsules develop, becoming about the same length as the bracts; they are sessile and ovoid-oblongoid in shape. Eventually, these capsules release numerous minute seeds that are carried aloft by air currents. The root system consists of a few roots that are fleshy and fibrous. Cultivation: The preference is dappled sunlight to light shade, moist to mesic conditions that are well-drained, and soil containing loam or clay-loam with some decaying organic matter. In addition to these requirements, appropriate strains of a fungus or fungi should be present in the soil that can form a symbiotic association with the root system. [图片]Range & Habitat: The native Lesser Ladies' Tresses has been found mostly in southern and central Illinois, where it is uncommon (see Distribution Map). However, this species appears to be slowly spreading into other parts of the state. Habitats include moist to mesic woodlands, rocky upland woodlands, open woodlands, areas along paths in woodlands, edges of swamps, and semi-shaded areas along abandoned fields. Lesser Ladies' Tresses appears to flourish when disturbance reduces competition from shrubs, trees, and tall vegetation. Such disturbance may be related to fire, wind storms, or human actions. In the wooded habitats where this wildflower occurs, the dominant trees are deciduous. Faunal Associations: Various kinds of bees visit the flowers of Spiranthes spp. (Ladies' Tresses Orchids) for nectar, including bumblebees, Halictid bees, leaf-cutter bees (Megachile spp.), and little carpenter bees (Ceratina spp.). The foliage and flowers are browsed occasionally by mammalian herbivores, including the White-Tailed Deer, Cottontail Rabbit, and Groundhog. Because of its small size and inconspicuous nature, Lesser Ladies' Tresses can be overlooked by these herbivores, however. Photographic Location: In a wooded area of a park in Champaign County, Illinois. Comments: There are two varieties of Lesser Ladies' Tresses. The typical variety requires cross-pollination by insects to produce fertile seeds; it is found in several southern states. The other variety, Spiranthes ovalis erostella, has a more northern distribution that includes Illinois. This latter variety lacks some of the reproductive structures (specifically, the rostellum and viscidium) that prevent self-pollination. Therefore, in the absence of cross-pollination by insects, this variety of Lesser Ladies' Tresses is capable of self-pollination, increasing the likelihood that seeds will be produced. Lesser Ladies' Tresses can be distinguished from other Spiranthes spp. (Lady Tresses' Orchids) by its small size (typically 3-6" tall), small flowers (tepals less than 6 mm. long), and narrow flowering stalks. In particular, the base of the lower lip of each flower has a pair of slender curved callosities (resembling minute claw-like extensions) that are distinct for this species. In contrast, the callosities of a more common species, Spiranthes cernua (Nodding Ladies' Tresses), resemble a pair of wart-like protuberances at the base of the lower lip of each flower. This distinction usually requires a 10x hand lens to see.

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Miss Chen

2018年05月25日

Description: This perennial wildflower is about 1-2¼' tall, consisting of loose clumps of unbranched leafy stems that are more or less erect. The central stem of each plant is medium green, slender, terete, and glabrous; it has a pair of longitudinal wings (about 0.5 mm. in length). At intervals, pairs of opposite sessile leaves occur at intervals along each stem. These leaves are 2-4" long and 1-2½" across; they are ovate-cordate, ovate, or lanceolate in shape and their margins are smooth (entire). The upper leaf surface is dark green and glabrous, while the lower leaf surface is medium green and either glabrous or pubescent along the veins. Leaf venation is pinnate; the lateral veins are curved, rather than straight. Above the uppermost pair of leaves, there occurs a spike-like raceme of flowers on a peduncle about 2" long. This raceme is about 1-4" long and curves to one side; about 2-10 flowers occur along the upper side of the raceme, where they are ascending to erect. Each flower is about 1½" long, consisting of a scarlet tubular corolla with 5 upper yellow lobes, a short green calyx with 5 narrow teeth, 5 slightly exerted stamens, and a pistil with a strongly exerted style. The tubular corolla is more narrow toward the bottom than the top; its upper lobes are slightly recurved, widely spreading to ascending, triangular in shape, and about 8-12 mm. in length. The teeth of the calyx are 5-8 mm. long and narrowly linear-lanceolate in shape. The base of the calyx is tubular and very short. The short pedicels of the flowers are up to 2.0 mm. in length. The blooming period occurs from late spring to early summer (rarely later), lasting about 1 month. There is no noticeable floral scent. Afterwards, the flowers are replaced by 2-celled seed capsules that are 4-6 mm. tall and 6-10 mm. across at maturity. Each cell of the capsule contains a few seeds. Later in the summer, these capsules split open to discharge their seeds explosively. The root system is fibrous and rhizomatous. Clonal offsets often develop from the rhizomes. Cultivation: The preference is partial sun to light shade, moist conditions, and a fertile loam with abundant organic matter. This plant can be propagated from stem cuttings (dipped in growth hormone) or by division of the root system. Seeds should be planted in the ground as soon as possible. Insect pests and disease organisms rarely bother the foliage. Indian Pink can be cultivated in areas that are north of its natural range (in Zones 4 or 5). Range & Habitat: The native Indian Pink is occasional in southern Illinois, while in the rest of the state it is absent (see Distribution Map). Illinois lies along the northern range-limit of this species. Habitats include bottomland woodlands, wooded areas along streams, and edges of swamps. This wildflower is found in high quality natural areas. [图片]Faunal Associations: Ruby-throated Hummingbirds cross-pollinate the flowers, from which they receive nectar. Aside from this, little is known about floral-faunal relationships for this species. The foliage and roots of Indian Pink are usually avoided by mammalian herbivores because of their toxicity from alkaloids and calcium oxalate crystals. However, White-tailed Deer may browse on the foliage sparingly in some areas. Photographic Location: A bottomland woodland in southern Illinois. Comments: Indian Pink has attractive flowers with striking colors. It is the only member of the Logania family (Loganiaceae) that is native to Illinois. Once the distinctive flowers are in bloom, it is very easy to identify this plant. In the past, the roots of Indian Pink were used as a vermifuge (to expel intestinal worms), however this practice has been largely discontinued because of the potentially dangerous side-effects. Other common names of this plant are Pinkroot and Worm-Grass.

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Miss Chen

2018年05月25日

叶斑病菌在病残体或随之到地表层越冬，翌年发病期随风、雨传播侵染寄主。鸡冠花褐斑病夏秋（8-9月）病重，鱼尾葵叶斑病夏季高温病重，君子兰叶斑病春、秋发生，但温室中四季均可发生。连作、过度密植、通风不良、湿度过大均有利于发病。今天要为大家介绍的是芭蕉叶斑病。 [图片]芭蕉叶斑病常见的有两种，即黄条叶斑病和黑条叶斑病。近两年来，时有发生，芭蕉叶片受害面积常占叶片总面积的20％～40％，严重时达80％以上，病株的大多数叶片干枯死亡。　一、病症黄条叶斑病发病初期是在植株顶部第三或第四片嫩叶上表面出现细小的黄绿色病纹，病纹与叶脉平行纵向扩展，形成黄绿色或黄色条纹，之后条纹再扩展形成暗色斑块，出现水渍状，中央变褐色或锈红色，边缘有黄色晕圈环绕，以后斑块或条纹的中央组织干枯。发病严重时，多个病斑或条纹相互融合，周围组织坏死，叶片大面积变黑干枯和迅速死亡。黑条叶斑病初时出现在完全展开的第三或第四片嫩叶下表面的叶脉间，有细小的褪绿色斑点。斑点扩展成锈褐色条纹，随后颜色加深，变成暗红色、褐色或黑色。严重受害叶片，病斑或条纹融合，造成大面积叶肉组织毁坏，变成黑色和水渍状，最后病叶迅速死亡、干枯、下垂，倒挂在假茎上。叶斑病属真菌性病害，在高温高湿的天气条件下易发生流行，尤其是台风暴雨后，叶片造成伤口多，发病更为严重。以密植、不除吸芽、土壤排水不良、蕉园四周杂草丛生、管理不周、偏施氮肥、通风条件差的蕉园发病最为常见。 [图片]二、防治方法 1、加强肥水管理：增施有机肥和磷钾肥，避免偏施氮肥，促使植株生长健壮。同时在香蕉新叶抽出展开时，用核苷酸、高美施、喷施宝或磷酸二氢钾进行根外喷施，增强树势，提高其抗病能力。 2、注重蕉园护理：及时挖通蕉田排灌沟，做到能排能灌；清除园内杂草，挖除多余吸芽，降低蕉园湿度，保持畦面干爽湿润，以利生长，减少发病。 3、清理病叶枯叶：对发病较重的植株，及时剪除植株上的重病叶片和枯死叶片，清除地面的病残叶，搬出园外烧毁，减少菌源，使果园通风透光，降低湿度，减轻危害。 4、适时喷药防治：在发病初期、清除病叶后以及大风暴雨后及时用药防治，每隔7～10天喷1次，连续喷3次。防治药剂可选64％杀毒矾800倍液、70％代森锰锌700倍液、77％可杀得1000倍液、25％必扑尔1000倍液等，以上药剂要交替使用，避色产生抗药性，提高防效。

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Miss Chen

2018年05月25日

植物受到伤害，伤在眼前，痛在心里。今天就为大家来介绍一种可恶的病害——白粉病。白粉病是一种真菌性病害。真菌其实在我们的生活中很常见，通常我们吃的橘子，放置时间久了发霉产生的白色至青色的毛毛其实就是真菌。白粉菌也是一种真菌，当他们寄生在植物的组织中时，就会对植物产生危害。 [图片]为害作物：植物。白粉病可使月季、玫瑰、蔷薇等木本花卉的苗木染病，也能使菊花、凤仙花、瓜叶菊、福禄考等草本花卉秧苗染病。为害症状：主要在叶片、嫩梢上布满白色粉层，白粉是病原菌的菌丝及分生孢子。病菌以吸器伸人表皮细胞中吸收养分，少数以菌丝从气孔伸人叶肉组织内吸收养分。发病严重肘病叶皱缩不平，叶片向外卷曲，叶片枯-死早落，嫩梢向下弯曲或枯死。发病特点：白粉病的病原为一类专性寄生菌，在同一种植物上，有时可以被一种以上的白粉菌侵染。蔷薇白粉病(Sphaerotheca pannosa)是月季、玫瑰、蔷薇、桃花等苗木普遍发生的病害。蔷薇白粉病菌一般以菌丝体在休眠芽内、病叶、病梢上越冬。翌年条件适宜时形成分生孢子，借风力传播。当气温17-25℃、湿度大时病害重，尤以21℃、空气相对湿度97％～99％时发病最重。凤仙花白粉病(S. fuliginae)可侵染凤仙花、百日草、波斯菊、大金鸡菊、三色堇、木槿、玫瑰、瓜类等。有人认为律草单丝壳菌(S. humuli)可侵染凤仙花。律草单丝壳在高温高湿时发病重。 [图片]菊花白粉病(Erysiphae cicheracearum)可侵染紫藤、枸杞、凌霄、福禄考、风铃草、美女樱、飞燕草、蜀葵、菊花、瓜叶菊、金盏菊、百日草、非洲菊、金光菊、大丽花、向日葵等秧苗(苗木)o有人认为菊粉孢(Oidium chrysanthemi)是菊花白粉病的主要病原，并侵染瓜叶菊、非洲菊等。菊花白粉病菌以闭囊壳随病残体在土表越冬，在南方和北方温室不存在越冬问题。以20～24℃、空气干燥时发病最重。菊粉孢以子囊果在受害组织上越冬，翌年子囊果开裂，散出子囊孢子借风传播，在温和、干燥天气下发病重。山楂白粉病(Podosphaera oxyacanthae)可侵染山楂、榆叶梅、麻叶绣线菊、中华绣线菊等。此外，还许多白粉病病原。防治方法： 1．选用抗病品种繁殖如月季有高抗白粉病的品种。 2．清除病源及时清扫落叶残体并烧毁。不用可能带有白粉病菌的床土培育容易感染白粉病的秧苗。不用有白粉病的母株扦插、分株。避免适合白粉病菌生长的最适湿度持续时间过长。 3．药剂防治发病初期用下列可湿粉药剂防治：25％粉锈宁2000倍液，或45％敌唑铜2500-3000倍液，或64％杀毒矾500倍液，或70％甲基托布津1000倍液。隔7～10天喷药一次，刚发生时，也可用小苏打500倍液，隔3天一次，连喷5～6次。今天给大家分享一下不用杀菌药物的处理方法 ●使用小苏打：白粉病在碱性状态下是不能存活，每50g小苏打兑水50kg可以有效防止白粉病！ ●使用食醋：按照1：50的比例兑水擦拭患病植株，并喷洒叶片，也能有效的减少病症 ●使用夹竹桃：夹竹桃叶子捣碎加清水泡一天左右，滤出汁液，喷洒患病植株或，连续使用3-4天能起到治疗作用，不过使用夹竹桃注意有毒，保护好自己。

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Miss Chen

2018年05月25日

黄化病，是植物的一种病征。指茎叶的一部或全部退绿，而出现黄化或黄绿化的现象。这种病有的是由于线虫、细菌类、病毒、支原体等病原体而引起的疾病；有的是由于养分的过分不足而引起的生理性疾病。今天要说的是杜鹃的黄化病。 [图片]杜鹃黄化病属生理性病害，但黄化病的形成，原因复杂，如肓目防治，往往徒劳无益，故必须仔细进行观察，确定病情，找出病因，然后对症下药，方能奏效。兹就杜鹃黄化病的各种症状、病因及有效防治措施，分述如下：一、缺铁。 1、土壤缺铁：叶绿素的形成，需要铁、氮等元素，而土壤缺铁造成黄化病的现象经常出现，因此补充土壤中的铁元素至关重要，可用硫酸亚铁粉末匀撒入盆土表面，直径30厘米盆可用1.5克，依此类推，然后喷大水使溶解水中，也可溶入水中浇灌，浓度为1%，或加硫酸锌、硼砂等也可，直至恢复。树干较粗大的植株也可用0.75%硫酸亚铁缓缓注入树干中，加以防治。 2、土壤或水偏碱，pH值增大时，严重影响根系对氮和铁的吸收，叶片自下而上逐渐黄化脱落，应首先用食醋中和水的碱性，使pH值降至5-6间，再行浇灌。土壤可用1、2项所述办法改造或更换盆土，严重时可在硫酸亚铁溶液中增加0.3%的柠檬酸，搅匀施用，以增加粘着持久效果。二、选好栽培土。宜用疏松、排水良好、富含腐殖质的酸性沙质壤土，可选用腐叶土7份、园土2份、砂土1份、混合配制，并加少量（每盆约50克）麻酱渣、骨粉等作为栽培土；忌用含石灰质的碱土或排水不良的粘质土壤；在栽培管理过程中，要干而不裂，潮而不湿，才能促进新根的萌发。 [图片]三、注意防肥害。杜鹃根细如丝，对肥料浓度反应极为灵敏，过浓会出现黄化、脱落，甚至枯死现象，尤其一旦得黄化病，应立即停止施肥；根外施肥有一定的作用，但不解决根本问题，再稳定一段时间，待新生绿枝木质化后方可施肥，否则仍有可能再次黄化。四、要舍得摘除花蕾。患黄化病的植株，即使花蕾成熟也是开不好花的，但因开花要大量消耗养分，影响病株复原，故应及早将所有花蕾不论大小，一律摘除。五、光照必须适宜。叶绿素的形成需要光照，只有充足的阳光，才能使叶片显现正常的绿色，光照不足会使叶片黄化。但病株根系衰弱，叶片在强光下以易萎蔫，故夏秋强光高温季节须遮阳，晚秋、冬春要适当增加光照，以利病株复原。总之，杜鹃花一旦得黄化病后，应耐心改善养护条件，对症采用上述有效防治措施，准备半年至一年左右的时间，精心护理，可使病株再现生机。

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Miss Chen

2018年05月25日

植物（草本和木本植物）燃烧后的残余物，称草木灰。属于不可溶物质。草木灰肥料因草木灰为植物燃烧后的灰烬，所以是凡植物所含的矿质元素，草木灰中几乎都含有。草木灰质轻且呈碱性，干时易随风而去，湿时易随水而走，与氮肥接触易造成氮元素挥发损失。 [图片]草木灰不仅能供给花卉钾素等营养元素，而且对防治花卉病虫害有较好的作用。防治叶枯病：用草木灰、茶饼、硫磺粉各1公斤，石灰1.5公斤，捣碎成粉后混合均匀，对易发生叶枯病的花卉每盆撒施1.5至2.5克。防治叶斑病：用草木灰3公斤、生石灰粉1公斤混合拌匀后撒施，每盆40至60克，或过筛喷粉，或单独撒施草木灰。防治根腐病：草木灰对花卉根腐病有很好的防治效果。具体操作方法是先扒开根部的土壤，并清除腐根周围的泥土，刮去发病根皮，每株施入0.5至1公斤草木灰覆盖根部，上面覆盖泥土。防治白粉病：对发生白粉病的花卉可距主干5至10厘米处，扒去深5至10厘米的根部土壤，每株盖草木灰0.5至3公斤，灰上加盖薄上。防治苗期病害：花卉苗圃地苗期易发生立枯病、炭疽病等，在湿度大、温度低时，苗病发生重，常大量死苗。可用草木灰顺垄撒施，亩用量20至25公斤。 [图片]防治蚜虫：将草木灰研末过筛，清晨露珠未干时（或先洒水）喷施草木灰于蚜虫体上，也可用纱布装灰抖撒，隔三五天再撒一次，连撒2至3次。防治根蛆：在花卉苗期根蛆危害时，如用农药灌根防治易发生药害，可在苗地亩施30至40公斤草木灰。施用方法是在苗期把草木灰均匀撒在畦面，然后翻锄均匀，使灰与土充分混合。也可在播种前或种植前，先把草木灰施在沟里，然后再播种或种植。防治地下害虫：育苗时，球根类花卉苗地常遭蛴螬等地下害虫危害，用草木灰作底肥防治，或用草木灰覆盖种块，可明显减轻危害。

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Miss Chen

2018年05月25日

由于几天没回家，今天一回家发现盆栽的藤小伊月季花最外面的花瓣居然有好多小黑虫，当即立刻将那片花瓣摘除，喷药。现在在担心其它花瓣被传染。相信很多友友都有过此情况发生吧。所以今天给大家分享几个土农药的制作方法，这样可避免农药给植物带来的副作用。一起来学习一下吧。 [图片]一、大蒜汁液。取紫皮大蒜0.5千克，加水少许浸泡片刻，捣碎取汁液，加水稀释10倍，立即喷洒，可防治蚜虫、红蜘蛛、蚧虫若虫；将大蒜汁液浇入盆土中可防治线虫、蚯蚓。二、烟叶水。取烟叶50克或烟梗、吸剩的烟头100克，加水1.5千克，煮沸半小时，或浸泡一昼夜，用手反复揉搓后，用纱布过滤，并加入0.1%?0.2%中性洗衣粉喷洒，可防治蚜虫、红蜘蛛、叶蝉、蓟马、熔象、卷叶虫及其它多种食叶害虫。三、辣椒。取干红辣椒50克，加清水1千克左右煮沸10分钟?20分钟，过滤后取其清液喷洒，可防治蚜虫、红蜘蛛、白粉虱等。 [图片]四、花椒。取花椒（或胡椒）50克，加水1千克左右，煮沸30分钟?40分钟，过滤后喷洒植株，可杀死蚜虫。五、白头翁煮水。取白头翁球根500克，加水5千克煮沸半小时，过滤后喷洒花卉，可杀死蚜虫。六、桃叶煮水。取桃叶0.5千克，加水3千克左右煮沸30分钟，过滤后喷洒，可防治蚜虫、尺蠖及软体害虫等；将桃叶切碎晒干后，碾成粉末施入土中，可防治蝼蛄、蛴螬等地下害虫。七、洗衣粉液。选用中性洗衣粉1克，兑水150克左右，喷洒受害花卉，可杀死蚜虫、红蜘蛛、白粉虱、介壳虫等。但要在杀死害虫后，及时用清水喷洗叶片2次?3次，疏通气孔。

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