Sclerotinia sclerotiorum is the main disease in rapeseed production. The rapeseed production area in our district, such as Beauchamp, and other townships within the circle, has the most serious incidence. The incidence rate is 10% to 50%, and the yield loss is 5% to 30%.
Symptoms: On the neck and petioles close to the ground during the seedling stage, red-brown spots are formed and then turned to white. The diseased tissue becomes soft and rot, with white hyphae, and severe cases can cause seedling death. The adult leaves, stems, flowers, fruits and seeds can all be susceptible. After the leaves became infected, the primary dark blue water stained patches developed and then expanded into round or irregular large spots. The lesions are gray-brown or tan, with concentric ring veins, dark cyan outside, and yellow halo outside. The lesions spread rapidly when wet, and the whole leaf rots; when the skin is dry, the lesion breaks and perforation. The lesions on the stems were watery, light brown, elliptical, prismatic, and long in shape. The lesions are slightly concave, with concentric ring patterns, white in the middle, brown edges, and obvious junctions between disease and health. When the disease is serious, the diseased stems are covered with flocculent hyphae, so they are called "white culms", "mild stalks" and so on. At this point the plants are dry and dead or mature earlier, visible longitudinal cortex. Syrup sensations form irregular white lesions. After the seeds are infected, the surface is rough and gray and white. Both the size of the stem and the inside of the stem and the pods can be formed in different sizes of rat sac. Pathogens and pathogenicity: The pathogen is Sclerotinia sclerotiorum. The bacterium sclerotia is mainly found in summer (winter rape area) and wintering (winter and spring rape area) on the soil, seeds and stubble or other hosts.
Control methods: 1 selection of disease-resistant varieties. 2 reduce the initial dip source. For example, the rotation of dryland rapeseeds should be more than two years, and should be implemented in large areas; seed selection and seed treatment: select disease-free strains to retain seed, sieve out large sclerotia in seeds, and then use salt water (5 kg Water is added with salt 0.5-0.75 kg) or ammonium sulfate water (5 kg water plus 0.5-1 kg ammonium sulfate) is selected and externally used for washing; it can also be soaked in warm water at 50°C for 10-20 minutes or 1:200 for formalin Soak for 3 minutes. After the rape cultivation, deep plowing, cultivation of rapeseed soil during the pumping period. 3 Improve the ecological environment of rapeseed. Such as re-basal fertilizer, Miao Fei, early application or control Shi Lei manure, Shizuo phosphorus, potash, to prevent the greed green lodging. The narrow trenches are deep and the trenches are stain-proof. Remove diseased, yellow, and old leaves at the flowering stage of rapeseed. Timely sowing, appropriate late broadcast. 4 chemical control. The type and amount of the agent are: 40% sclerotium net (formerly known as grain moxibustion) wettable powder 1000 to 1500 times liquid 1 to 2 times, 50% carbendazim powder or 40% exterminate disease suspension 500 times liquid 2 to 3 Times, 70% thiophanate-methyl wettable powder 500 ~ 1500 times 2 ~ 3 times, 50% fast-king powder 2000 times 2 ~ 3 times. The above liquid dosage is 100-125 kilograms per acre. In the flowering period of rapeseed, the rate of diseased leaves is more than 10%, and when the rate of stem diseases is less than 1%, spraying is started. Each interval is 7-10 days. 5 biological control. The biocontrol preparation is generally applied to the soil. The better control effect is the preparation of Coprinus comatus, Trichoderma and other preparations.
Ppe Isolation Protective Suit,Industrial Coverall Protective Clothing,Ppe Protective Suit,Lightweight Protective Suit
GULF STAR MEDICAL MANUFACTURING FZE , https://www.gulfstarmedical.com