Field management of wheat-intercropped cotton must be followed up in time
1. Growth and development characteristics of wheat-intercropped cotton. For wheat-intercropped cotton, the cotton seedlings are weak after wheat harvest, grow and develop slowly, bud and flower late, are prone to excessive vegetative growth in the mid-season, and tend to mature late in the late season; moreover, this year the cotton seedling stage was affected by rainfall and low temperatures, and seedling diseases were relatively severe.
Field management after wheat harvest must be based on the word "early" and vigorously grasp the word "quick" to promote rapid growth and development of the cotton seedlings so as to make up for insufficient growth during the seedling stage.
2. Quickly destroy the wheat stubble and loosen the soil. In wheat-intercropped cotton fields, the soil is severely compacted, the seedlings are weak, and diseases are severe, so quickly destroying the wheat stubble and loosening the soil is the first step in field management. "To develop seedlings, first develop roots." To promote strong seedlings and early development, root growth must first be promoted. After wheat harvest, quickly destroy the wheat stubble and loosen the soil to break up soil compaction, achieving deep inter-row cultivation of 7-10 cm and shallow hoeing between plants of 3-4 cm, so that the soil around the cotton seedlings is loose and breathable, which can effectively reduce diseases and has a good effect on promoting strong seedlings and early development.
3. Quickly apply seedling-promoting fertilizer. In wheat-intercropped cotton fields, most of the soil nutrients are consumed by @#@245@#@, and the cotton seedlings lack the nutrients they need, which seriously affects growth and development, so fertilizer must be applied as early as possible after destroying the stubble. Generally, 7-9 kg of urea per mu must be applied as topdressing. For plots with insufficient base fertilizer, 1000-2000 kg per mu of decomposed high-quality farmyard manure is also needed to promote rapid growth and development of the cotton seedlings.
4. Quickly irrigate with seedling-promoting water. In the Huang-Huai region of China, there is a relatively long period of drought after wheat harvest, and the soil moisture in wheat-intercropped cotton fields is often seriously insufficient. The field water-holding capacity of the 50 cm soil layer is mostly less than 50%. In conjunction with topdressing, quickly irrigate once with seedling-promoting water to achieve the use of water to promote fertilizer and fertilizer to conserve water. Dig trenches every other row for irrigation, and strictly avoid flood irrigation; after irrigation, cultivate in a timely manner to conserve soil moisture.
5. Quickly control insect pests. During the seedling stage of wheat-intercropped cotton, field pests are generally more numerous and more severe than in pure cotton stands. After wheat harvest, pests such as corn borers, cotton bollworms, and red spider mites on wheat move to cotton.
After wheat harvest, quickly carry out field pest investigation and control. Choosing highly effective and low-toxicity pyrethroid pesticides can effectively control various pests such as corn borers, cotton bollworms, red spider mites, and cotton aphids. Where conditions permit, a 100-150 times diluted Bt formulation spray can be chosen, which has a good control effect on corn borers and cotton bollworms and does not pollute the environment, and is worth promoting according to local conditions.