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What kind of colorful-leaf tree is the golden-leaf honeylocust?
Golden-leaf honeylocust (Gleditsia triacanthos 'Sunburst') is a plant in the genus Gleditsia of the family Caesalpinioideae. A broadleaf deciduous tree, it grows rapidly and has no branch thorns; the young leaves are golden yellow, the mature leaves light yellow-green, and in autumn they turn golden yellow. Its branches spread out gracefully, giving it a beautiful form, and it does not produce fruit. The honeylocust has strong adaptability, prefers light but tolerates slight shade, drought and cold, and can withstand low temperatures of around -25°C. It likes a warm, humid climate and deep, fertile, appropriately moist soil
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What are the control methods for azalea leaf spot?
1. Symptoms: Small reddish-brown spots first appear on diseased leaves, gradually expanding into nearly circular spots, or restricted by leaf veins into polygonal lesions, 1-5 mm in diameter, dark brown; sometimes grayish-white in the center with indistinct edges. The spots are darker on the upper surface and lighter on the lower surface of the leaf, and lesions at the leaf margin may merge with one another; when humid, grayish-black mold spots mostly form on the surface of the diseased areas. 2. Pathogen: The pathogen of azalea leaf spot is Cercospora rhododendri Ferraris, belonging to the order Hyphomycetales, class Hyphomycetes. The grayish-black mold spots on the lesions are
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Symptom Identification and Control Methods for Peach Leaf Curl
Peach leaf curl is a common disease in spring, mainly affecting ornamental peach, cherry, apricot, plum and others. 1. Pathogen: The disease is caused by fungi of the class Taphrinomycetes in the phylum Ascomycota. 2. Symptoms: It mainly affects leaves, and in severe cases can also affect flowers, young fruit and tender shoots. After leafing out in spring, infected plants show shrivelled, rippled leaves with the leaf tip and margins curling backwards and the leaf surface uneven. As the leaves grow, the leaf colour gradually changes from yellow-green to purplish-red, the mesophyll thickens and becomes brittle, and the unevenness increases. In late spring and early summer, the leaf surface develops
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Symptom Identification and Control Methods for Ginger Leaf Blight
[Pathogen scientific name] Septoria zingiberis [Host crop] Ginger. [Disease diagnosis] It affects the leaves. When the leaves become diseased, small water-soaked spots appear at first, and after gradually expanding, the lesions become nearly fusiform, light brown, with a grayish-white center; later the lesions extend upward and downward into long streaks. Many small black dots are scattered on the lesions. In severe cases, the lesions may split longitudinally, and the leaves die. The pathogenic fungus is Septoria zingiberis. The pycnidia are superficial or borne on both sides of the leaf, spherical or subspherical, dark brown, and contain
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Symptoms and Control Methods of Ginger Leaf Spot Disease
[Pathogen scientific name] Phyllosticta zingiberi Hori [Host crops] Ginger, white cardamom. [Disease diagnosis] Mainly affects leaves. Leaf spots are spindle-shaped or oblong, 3-5 mm long, with brown margins and yellowish-white, thinned centers that easily rupture or perforate; later, numerous small black dots appear on the surface of the spots. When the disease is severe, the entire leaf is densely speckled with spots. The pathogen is Phyllosticta zingiberi. The fungal pycnidia are spherical to flattened spherical, dark brown. Conidia are single-celled, elliptical.
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What to do when cotton develops red leaf blight during the boll-setting stage
Control measures for cotton red leaf blight: 1. Apply fertilizer reasonably, and skillfully apply the cotton topping fertilizer; nitrogen, phosphorus and potassium should be applied together or foliar fertilizer should be applied. 2. Strengthen field management, cultivate frequently, improve root respiration conditions, promote root development, prune and remove side branches in time, remove old leaves and control pests and diseases. 3. Spray for protection, using 70% mancozeb or 75% chlorothalonil 600-800 times solution or 70% thiophanate-methyl 800-1000 times solution plus foliar fertilizer (potassium dihydrogen phosphate, Lvzhiyuan, etc.) for spraying, once every 5-
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Occurrence Patterns and Control Methods of Cotton Red Leaf and Stem Blight
Disease symptoms and occurrence patterns: Cotton red leaf and stem blight is an explosive disease that frequently occurs in the middle and late stages of cotton growth. It can cause leaves to turn red from bottom to top until they drop off. The leaf veins remain green, the leaf mesophyll turns red, and the leaves become thicker, brittle, and wilted before finally dropping. When the stem is cut open, it does not change color, which distinguishes it from cotton Fusarium and Verticillium wilt. Generally, in old cotton-growing areas, the disease is more severe in cotton fields with continuous cropping year after year, sandy soil, too shallow a plow layer, or insufficient fertilizer lacking potassium fertilizer. Drought in the middle and late stages, along with severe potassium and zinc deficiency in the soil, can also easily accelerate the occurrence of this disease.
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What are the three main causes of cotton red leaf stem blight?
Cotton red leaf stem blight is a physiological disease caused by potassium deficiency. It occurs in the middle and late stages of cotton growth, and in dry years the occurrence and severity of damage are more serious. In the field, cotton generally begins to show symptoms at the bud stage, and the disease is most severe during the boll-setting and boll-opening stages. Symptoms mainly appear on the leaves. Diseased leaves develop from top to bottom and from the outside inward. Diseased leaves begin to lose green color from the edges, first turning yellow, then producing red spots, and finally the whole leaf turns red, the mesophyll thickens, wrinkles and becomes brittle, while the veins remain green. In severe cases, the leaves of the whole plant lose green color, then turn red and brown, the leaves scorch and fall off, leaving bare stems, and the plant
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How to prevent cotton red leaf stem blight? These integrated measures must be mastered
Cotton red leaf stem blight is a physiological disease. In recent years, it has occurred in large amounts in the cotton region of the Yangtze River Basin in our area. It begins at the early flowering stage, and is more severe and widespread from the full flowering stage to the boll-setting stage. In our area specifically, it occurs sporadically in July and August. It reaches its peak from mid-to-late September to October. Lightly affected plants are yellow and thin, with few and small bolls, short fiber, and poor boll opening; severely affected plants die prematurely, and the bolls cannot mature, greatly affecting yield. 1. Disease symptoms. At the early stage of the disease, red and purple spots appear on the leaves, gradually spreading until the whole leaf turns red
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How to prevent and control cotton red leaf stem blight? A full analysis of control measures
I. Symptom identification After the plant is affected, the leaves turn dark green and become thick and brittle, then small red dots are scattered on the leaves, and finally the whole leaf turns red while the veins remain green, which is red leaf stem blight. When the disease is severe, the base of the petiole becomes soft, loses water and shrinks, causing the leaves to wither and fall off, and the top of the stem becomes scorched and dry. At the same time, it easily triggers repeated infection by target spot and brown spot, causing the diseased plant to scorch and die. Some plants can still grow adventitious buds after the diseased leaves fall off. Plants with severe and early onset are short, with poor root development, and both the main root and lateral roots are
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