How to produce good seedlings of improved Cotton varieties

At present, most cotton areas in our country use nutrition pot seedling. General evaluation of good or poor cotton seed emergence, one depends on the emergence rate, the second must be regarded as seedling rate. The low emergence rate of the reasons, one is that some cotton seeds, autumn peach or late autumn peach proportion is too large, reduce the germination rate. However, the germination rate of peach or mid-term flower selected as seed is more than 80%; secondly, in the process of cotton seed processing, the control is not strict, and the damaged seed exceeds the standard; thirdly, the pot soil and cover soil are not disinfected with chemicals before or after sowing of cotton seeds, or the selected disinfection drugs are not correct; fourthly, the weather continues to be dry after sowing of cotton seeds this year, and many farmers with insufficient watering during sowing are poor in seedling emergence; Fifthly, the soil after sowing is too deep or too shallow, the seedling potential of too deep is weak, and the seedling with shell or foot is too shallow; sixth, the cotton seedling is not sprayed in time to protect the leaves after emergence, and the good cotton seedling is infected with dead seedling. As for the reason why the seedling rate is not high, some farmers reflect that the seedlings are good, but the dead seedlings are serious. According to the author's field inspection, one is infected with blight, anthracnose, damping-off dead seedlings, which account for more than 80% of the whole dead seedlings; the other is fertilizer damage or wrong pesticide damage cotton seedlings; the third is high temperature burning seedlings. No dead seedlings were found during the investigation.

Generally speaking, good cotton varieties have high yield and good quality potential. Compared with poor varieties, the emergence rate and seedling rate are higher, but good cotton varieties cannot be equated with high emergence rate and seedling rate. In the process of raising seedlings in cotton nutrition pots this year, the problem of low emergence rate and seedling rate of exposed improved cotton shows that some farmers are not good enough in sowing and seedling at one time. Therefore, we must sum up experience and lessons, in the next year's cotton seedling work, the following key points: First, we should choose high maturity cotton varieties, avoid using poor maturity cotton seeds; Second, we should sun seeds for 2~3 days before sowing, and remove broken seeds and tender seeds at the same time, which can improve the germination rate by 3%~5%; Third, we should change the seedbed every year to prevent residual germs in the soil; Fourth, we should spray and disinfect the seedbed bowl soil and the cover bowl soil; Fifth, it is necessary to spray Bordeaux mixture, Pu K, Shi Le Shi and other pesticides in time to protect cotton seedlings when two cotyledons of cotton emerge and spread; sixth, it is necessary to prevent drought damage, water damage, chemical damage, fertilizer damage, freezing damage and high temperature burning in the process of seedling raising.