The first is severely affected cottonseed, withered and verticillium wilt is one of the chronic diseases that restrict cotton production. Cottonseeds are also carriers of pathogens. Germs can spread rapidly with cottonseeds. Therefore, cotton seed that is in severe areas of dry and verticillium wilt cannot be transferred to the light-damaged cotton area, nor can it be transferred to the disease-free cotton area.
The second is peach and late autumn peach seed cotton. Fuchs peaches and late autumn peaches have poor growth and development, poor maturity, light boll weight, low seed germination rate, and fragile growth.
The third is the exploitation of peach seed, some cotton farmers for the development of a more full-fledged peach, still have the habit of robbing peaches. All cottonseeds that have been peeled off from peaches cannot be brought to market because they are not fully ripe and do not complete ripening.
The fourth is the spraying of ethephon cottonseed. Although spraying ethephon can promote the early maturing of cotton by 3-4 days, the damage to cottonseeds is relatively large, resulting in incomplete development and failure to plant seeds.
Fifth, serious degradation of species. Cotton is an out-of-breed crop. The out-cross rate is about 8%. Some cotton farmers have not changed new varieties for many years. The purity of cotton seeds is only 70-80%, and the quality is seriously degraded. Continued use will inevitably lead to a reduction in production and quality.
Six cottonseeds stored together with pesticides and fertilizers. Some farmers have stored cottonseeds, pesticides, and chemical fertilizers in a warehouse for a long period of time and have poor ventilation. Because the toxic gases emitted from pesticides and chemical fertilizers damage the normal physiology of cottonseed, the germination rate is drastically reduced.
Seventh, cotton seeds that have been stored for a long time. The average germination rate of cotton seeds stored for more than half a year is more than 80%. In the absence of low-temperature refrigeration equipment, the life span and storage age of cotton seeds have increased negatively.
Eight is the cotton seed that has been sunburned on the cement drying field. In the cement drying field, the cotton seeds with higher water content are irritated due to the strong respiratory intensity, which causes the physiological function of the cotton seeds to be disordered. Some of the cotton seeds form dumb seeds and lose their ability to germinate.
Nine is a cotton seed with excessive mechanical damage. In the finished coated cotton species, the mechanical damage rate should be controlled within 2%. Seeds with more than 2% seedbreaking rate are heavily infected with drugs and have a great influence on the germination rate. If the rate of seed breaking is too high, it is not suitable for seed use.