Cotton seedling red rot has occurred in various cotton areas in China. Especially in the Yellow River Basin, the highest incidence rate, up to 80%. The northern cotton area is mainly caused by serious disease at the seedling stage, and the southern cotton area is mainly affected by the bell stage. In severe cases, it will cause large dead seedlings and timely pesticide control to reduce losses.
Clip Spring,Metal Spring Clips,Spring Loaded Clips,Stainless Steel Spring Clips
applicaiton: viation,automotive, motorbike, bicycle, automatic equipment, household appliance, medical device ,toy, telecommunication,computer, instrument and meter,furniture, electric tools,mold and other industries
China Clip Spring,Metal Spring Clips,Spring Loaded Clips,Stainless Steel Spring Clips, we offered that you can trust. Welcome to do business with us.
Clip Spring,Metal Spring Clips,Spring Loaded Clips,Stainless Steel Spring Clips Shenzhen Lanejoy Technology Co.,LTD , http://www.copper-nut.com
The law of onset: cotton seedling red rot is caused by several species of Fusarium, mainly Fusarium oxysporum, followed by Fusarium oxysporum and Fusarium graminearum. The bacteria can overwinter on the inside and outside of the seeds, the rotten bells in the soil, and the dead leaves of the dead leaves, causing infection.
The most suitable temperature for the occurrence of diseases is 19 to 24 ° C, the relative humidity is more than 80%, the sunshine is small, the rainfall is large, and the rainy days are more. Several conditions are simultaneously matched, and the disease may be a pandemic. When it is rainy in autumn, the bacteria spread to the bell by wind and rain, insects, etc., causing rotten bells. The pathogen is weakly parasitic on the bell, and it needs to be infested by other diseases and insect wounds.
Under suitable temperature and high humidity conditions, the incubation period of the disease is about 3 days. If the temperature and humidity are not suitable, the incubation period can be extended to 8 to 10 days, even without disease. In addition, the occurrence of diseases is related to different growth stages of cotton seedlings. That is, when the cotyledon spreads to the cotyledon to increase green, and the lateral root grows more than 10, the root damage is the heaviest; at 2 weeks of seedling age, the cotyledon suffers the most, often causing all dryness; when the true leaf is unfolded, especially the true leaf is growing rapidly. The disease resistance is significantly enhanced and rarely causes dead seedlings. According to the China Pesticide Network , soils of different natures are also related to the occurrence of diseases. The incidence of saline-alkali soil is heavy, and the incidence of sandy loam is light. The incidence of low-lying cotton fields is heavy, and the cotton fields that are used for legume crops in the cotton field and the former crops are seriously affected. Premature sowing, cotton seedlings are poorly grown, and cotton fields are seriously affected. Cotton plants are greedy or cotton bolls are endangered by pests and diseases, and there are many mechanical wounds.
Control method:
1 Agricultural control attention to clean the pastoral, timely removal of diseased plants, timely removal of dead branches, fallen leaves, rotten bells, etc., concentrated burning, reducing the source of the initial infection of the bacteria. Sowing at the right time, strengthening the management of seedling stage, using formula fertilization technology to promote the rapid and robust growth of cotton seedlings and enhance the disease resistance of plants. Strengthen the management of cotton fields, timely control the pests and diseases of the bell period, avoid causing wounds, and reduce the chance of infection by bacteria.
2 Prevention before sowing:
Use good quality disease-free seeds or seed for seeding every year, and thoroughly disinfect the seeds. Pesticide manufacturers recommend using 50% carbendazim wettable powder or 50% five-multiple mixture seed coating agents 1 to 3, 20% dipyridone, 50% mancozeb wettable powder for seed dressing, the dosage is 300 ~ 500 grams of the drug is mixed with 100 kilograms of cottonseed. Seed dressing with alizarin can increase the seed vigor, and the root length, shoot length and fresh weight of the cotton seedlings are obviously improved. 0.1% alizarin lactone soluble powder 0.5 mg plus 10% C per 1 kg cotton seed. Cyclic emulsifiable concentrate 1g or 0.1% alizarin lactone soluble powder 0.5mg plus 20% triadimefon emulsifiable concentrate 1g, 0.1% alizarin lactone soluble powder 0.5mg plus 50% carbendazim WP 5g Seed dressing can significantly improve the control effect of fungicide on cotton seedling red rot.
3 Prevention and control opinions during the bell period:
Pesticide manufacturers recommend using 50% thiram double wettable powder 500 times solution, or 50% thiophanate-methyl WP 800 times solution, 70% mancozeb WP 800 times solution, etc., usually in 7 ~ Once every 10 days, spray 2 to 3 times in a row.
Summary of identification and control methods for cotton seedling red rot