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Symptoms and control methods of cotton boll Aspergillus rot
Symptoms It occurs in all cotton regions. It mainly damages cotton bolls. Initially, water-soaked yellowish-brown spots appear at cracks, insect holes, wounds or splits on the cotton boll, followed by yellow-green or yellowish-brown powdery material that fills the boll cracks, causing the cotton boll to fail to open normally. During continuous rainy weather or high humidity, yellowish-brown or yellow-green fuzzy mold grows, namely the pathogen's conidiophores and conidia, and the cotton lint quality is contaminated to varying degrees or becomes dry-rotted and deteriorated. Pathogen Aspergillus flavus Link, called yellow aspergillus, Aspergillu
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Identification and Control Methods of Cotton Seedling Red Rot
Symptoms This disease occurs in all cotton regions of China, with severe damage in the Yangtze River Basin and Yellow River Basin cotton regions, and it also occurs in the Liao River Basin. It can infect plants at the seedling stage and boll stage. When infected at the seedling stage, the young sprouts are damaged before emergence, and the sprouts become reddish-brown and rot. After emergence, the roots of affected cotton seedlings show yellowing of the root hairs and lateral roots, which later turn blackish-brown and rot. When the young stem is infected, the vascular bundles turn dark brown, yellow streaks appear at the base of the young stem near the ground, and later turn brown and rot. The young roots and young stems swell, and grayish-red irregular spots form on the edges of the cotyledons and true leaves. Under high humidity, a pink mold layer forms on the surface, which is the pathogen
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Control Methods for Cotton Anthracnose in Cotton Seedlings
Symptoms The disease can occur at the seedling stage and the adult plant stage. Infection at the seedling stage: damage after germination but before emergence can cause seed rot; after emergence, red-brown cracked streaks appear at the base of the stem, and as they expand and constrict they cause seedling death. In damp conditions, orange-red sticky material (the pathogen's conidia) forms on the lesions. Round or semicircular yellow-brown spots appear on the edges of the cotyledons, which then dry up and fall off, leaving the cotyledon edges incomplete. When cotton bolls are infected, small dark red dots appear at first, and after expanding they become brown lesions; the affected part is sunken and contains orange-red powdery material, namely the pathogen's conidia. In severe cases the whole boll rots, fails to split open, and the fibers become black hardened, discolored locks. Leaf lesions are irregular and nearly round, and tend to dry out and crack. Stem lesions are red-brown to dark black, oblong, sunken in the center, with the epidermis often breaking open to expose the xylem, and the stems break easily in wind. In production, cotton bolls infected in the later stage suffer severe damage and cause great losses.
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Identification of Honeysuckle Disease Symptoms and Control Methods
Brown spot disease is a common leaf disease that causes plants to grow weakly. It mostly occurs in the middle and late growth stages, with August and September being the peak period of onset, and it is severe under rainy and humid conditions. In the early stage of onset, small brown spots form on the leaves, then expand into brown round lesions or irregular lesions. Grayish-black mold-like substances grow on the underside of the lesions. When the disease is severe, the leaves fall off, affecting plant growth and flowering. Control method: prune diseased leaves, then spray with 1:1.5:200 Bordeaux mixture, once every 7 to 10 days, for 2 to 3 consecutive times. Powdery mildew occurs under warm and dry
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Symptom Identification and Control Methods of Licorice Rust
Latin scientific name: Uromyces glycyrrhizae Magn. Crops affected: Licorice. Symptoms: Mainly affects leaves. After seedlings emerge in spring, round, grayish-white small blister spots appear on the underside of leaves, and later the surface ruptures to reveal yellow-brown powdery masses, which are the pathogen's uredinia and urediniospores. In the late stage of the disease, the entire leaf is covered by uredinia, causing the aboveground part of the plant to die; the phloem tissue at the junction of the stem base with the root or stem proliferates, latent buds sprout, and the plant becomes clustered and dwarfed. After reinfection by urediniospores,
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What are the control methods for licorice rust disease?
① Pathogen The pathogen of licorice rust (Uromyces glycyrrhizae) belongs to Basidiomycota → Teliomycetes → Uredinales → Pucciniaceae → the genus Uromyces. ② Disease pattern a. Urediniospore stage In the seedling stage of licorice, infected plants show a light brown uredinium at the tip of leaves that have not yet unfolded. As the young leaves flatten and grow, the spore masses appear densely along the leaf tip and the underside of the leaf, and finally the entire underside of the leaf is covered by spore masses, appearing as a sheet of yellow rust color; generally all leaves of the whole plant become diseased, and diseased plants are noticeably dwarfed.
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How to control licorice aphids? Master these methods
They damage tender leaves, tender shoots, flowers and fruits. Adults and nymphs suck plant sap; in severe cases they can cause leaves to turn yellow and drop, affecting seed set and marketable yield. Control methods: ① Avoid planting next to leguminous plants. ② During the occurrence period, spray with 40% dimethoate emulsifiable concentrate at 1000 times dilution.
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Licorice Disease Prevention and Control Methods and Key Technical Points
(1) Rust disease: When infected, yellowish-brown scar-like lesions appear on the underside of the leaves. After the epidermis ruptures, brown powder is released; this is the uredinium of the pathogen. From August to September, dark brown telia form, causing the leaves to turn yellow and wither, and in severe cases to fall off. Control methods: Apply more phosphorus and potassium fertilizer to improve the plant's disease resistance. Remove diseased plant debris and burn it in a centralized manner. At the early stage of the disease, spray with 15% triadimefon at 1000 times dilution, or 97% diniconazole at 400 times dilution. (2) Brown spot disease: It damages the leaves, and affected leaves develop round or irregular lesions. The
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How to control the black locust grain moth? Detailed control methods
Control methods for the black locust grain moth: 1. During the peak emergence period of adults, spray 80% dichlorvos emulsifiable concentrate, or 4.5% beta-cypermethrin emulsifiable concentrate, or 2.5% deltamethrin at a 2000- to 4000-fold dilution. 2. During the larval damage period, apply a 1:30 dilution of 80% dichlorvos and kerosene, or a 1:20 dilution of diesel oil, brushing it onto the infested patches.
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How to control the black locust geometer moth? A full breakdown of practical methods
Control methods for the black locust geometer moth: 1. Manually dig the pupae out of the soil and feed them to poultry. 2. During the adult emergence period, pile sand at the base of the trunk or tie a 5 to 7 cm wide plastic film band to prevent the wingless moths from climbing the tree. 3. During the young larval stage, spray a 3000-fold dilution of 20% diflubenzuron, or a 2000-fold dilution of 50% phoxim emulsifiable concentrate or 20% fenvalerate insecticide emulsifiable concentrate. 4. Use light traps to kill the adults.
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