-
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.
-
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,
-
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
-
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.
-
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
-
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
-
Symptoms and Control Methods of Cotton Boll Red Rot
Symptoms After a cotton boll is infected, an irregularly shaped lesion initially appears. In wet weather or during continuous overcast and rainy days, the disease spreads rapidly, covering the entire boll, and in some cases reaching the cotton fibers, producing an even pink or light red mold layer. After rain, it easily sticks together, forming pink masses, causing the diseased boll to fail to crack open, and the cotton fibers to rot into stiff, matted locks. After seeds are infected, the germination rate declines. The pathogen is the same as that of cotton seedling red rot. Transmission route and disease conditions This fungus is a weak parasite and cannot directly infect cotton bolls; it mainly enters through wounds to cause disease. Cotton boll angular leaf spot
-
Identification and Control Methods of Cotton Stem Blight
Symptoms The disease occurs more severely in the Northeast cotton region, the Yellow River basin and the Yangtze River basin, and the cotton regions along the rivers and coast. Cotton can be affected throughout the entire growth period, with the seedling stage and bud stage suffering the most severe damage. When cotyledons and true leaves are infected, small round spots initially appear with purplish-red edges and grayish-white centers, after which the lesions expand or merge into irregular-shaped lesions. Some lesions develop concentric rings in the center, scattered with small black granules, which are the pathogen's pycnidia. The diseased parts often break apart and fall off. Under high humidity, water-soaked lesions appear on young tender leaves, then spread rapidly as if scalded by boiling water,
-
How to control cotton mirid bugs? These methods must be mastered
The occurrence of mirid bugs is very sensitive to the ecological environment. Mirid bugs prefer temperatures of 25°C~30°C and a relative humidity of 80%~90%. The recent humid weather with little sunshine is very favorable for the occurrence of mirid bugs. Intercropping in cotton fields is also conducive to the parasitism and transfer damage of mirid bugs. Now, soybeans, broad beans and other vegetables are intercropped in cotton fields everywhere, which is conducive to their reproduction. Therefore, some cotton farmers in cotton areas of counties and cities such as Hanchuan and Yunmeng in Hubei Province have recently reported that the occurrence and damage of mirid bugs have already emerged
-
Garlic leaves turning from green to brown and yellow: master the control methods for garlic leaf blight
Garlic leaves turning from green to brown and yellow: control methods for garlic leaf blight
条件筛选