Preventive measures of three pests in Cotton Seedling period

In the process of cotton planting, because of the types of diseases and insect pests, it is necessary to take good control measures, and in the process of cotton, there are also "three pests", that is, freezing injury, waterlogging injury and fertilizer damage. So how to prevent their harm? Let's take a look at the prevention methods with the editor.

1. Symptoms of frost injury

The freezing injury mainly occurred in the slow growth of seedlings, small leaves of true leaves, easy shedding of cotyledons, and wrinkling of young leaves, like aphids, and when serious, the stems and leaves withered and withered. There are three main reasons: first, sowing blindly too early, encountering a cold wave after emergence, and a sharp drop in temperature; second,

Uncover the plastic thermal insulation film prematurely; third, it is not covered in time at night after opening the film during the day.

Prevention methods: to prevent blind sowing, to understand the temperature requirements of cotton emergence, to achieve timely sowing, the lowest temperature of cotton germination is 10.5 degrees, and the emergence temperature is above 12 degrees; the second is to understand the local climatic conditions. generally, the air temperature in the Yangtze River basin in the first ten days of April is above 13 degrees, which can be sown in a large area after trial sowing. At the same time, after emergence, pay attention to cover the film early and late, so that the nutrition bowl seedlings do not transplant, the film can not leave the seedbed.

2. Symptoms of waterlogging injury

First, cotton seedlings from white to brown, and finally brown, seedling growth; second, seedling stem development is poor, toughness is poor, very easy to quench into pieces, but also easy to be infected with diseases such as bacterial blight. The main reason is that the drainage is poor, and it can not be drained in time after the rain, that is, the soil of the seedling bed is relatively sticky and heavy, and the water seepage performance is poor.

Prevention method: fine soil preparation of cotton seedbed, choose the address of seedbed can not be stubble, prevent residual bacteria infection, that is, the drainage system should remain unobstructed, it is best to increase the application of organic fertilizer, improve soil structure, so that spring rain can drop energy filter, rain stay in the bed dry.

3. Symptoms of obesity injury

Fertilizer damage will cause rotten cotton seeds after sowing, no emergence, and even after budding, it will also cause radicle and germ burns, and the emergence rate is very low; even in seedling households, it will cause root burns, scorched leaf edges of young leaves, serious leaf shedding and plant death. There are many reasons for fertilizer damage: first, the application of a large amount of urea in the base fertilizer results in the loss of water in cotton seed cells and inhibits the germination of seeds; second, the application of base fertilizer is too large and the concentration of soil solution is too high, resulting in reverse osmosis damage seedlings; third, the application of immature organic fertilizer produces high temperature seedling burning in the process of fermentation.

Prevention methods: in view of the possibility of fertilizer damage, take targeted preventive measures, first of all, the base fertilizer in the base fertilizer must be fully mature, so as to prevent high temperature burning seedlings. It can also prevent weeds and seedlings from competing for water and fertilizer. Second, it is forbidden to use urea as the base fertilizer of seedbed. In order to avoid seed dehydration and suffocation, in the application of chemical fertilizer, every 10 square meters should be controlled at about 0.75 kg.

The above is the introduction of cotton seedling period three harm prevention measures, hope to help you, want to know more related knowledge, please pay attention to us.