Cotton planting method reform should be combined with autumn sowing production

In recent years, to promote high cotton yields, the Ministry of Agriculture of the People's Republic of China has carried out a 10,000-mu high-yield cotton creation activity in the major cotton-producing provinces nationwide. Recently I inspected high-yield cotton fields in Hubei, Anhui, Jiangsu, Jiangxi and other provinces, and previously also conducted surveys in high-yield cotton fields in Hunan and Zhejiang provinces. The high-yield cotton creation goals are broadly the same across regions, but the planting patterns are not entirely the same, and the planting methods each have their own particularities.

Cotton yield is composed of indicators such as planting density, number of bolls per plant, boll weight and lint percentage, among which planting density is closely related to cotton yield, and planting density is inseparable from the planting method.

Before the 1980s, most cotton regions mainly planted conventional cotton, with a planting density of 3000-4000 plants per mu. With the promotion and application of cotton nutrient bowl seedling raising and transplanting and hybrid cotton, especially the demonstration and promotion of transgenic hybrid insect-resistant cotton, the planting density per mu gradually declined, but the extent of the decline varied among regions. In some provinces the planting density was about 1500 plants, in some about 1300 plants, and in others only about 1100 plants. As for the planting method, it also differed from place to place: some mainly used wide-narrow row planting, some mainly used wide rows with dense plants, some mainly used wide equal rows, and others used narrow rows with wide plant spacing, resembling a square block shape.

Through my on-site inspections, especially under the rainy and overcast climate conditions of July and September this year, in all cotton fields with relatively narrow row spacing (less than 1 m), the cotton canopy closed earlier, the cotton field had insufficient light, and bud and boll shedding was relatively serious. The general shedding rate was above 50%. Especially in cotton fields with excessive fertilization and a partial application of nitrogen fertilizer, bud and boll shedding was even more aggravated, with the shedding rate reaching above 60%. The number of rotten bolls per cotton plant reached ~10, and in some places rotten bolls were still occurring in mid-October, causing cotton yield reductions of at least 10%, and in many cases 20-30%. In cotton fields with relatively wide row spacing and good ventilation and light transmission, the bud and boll shedding rate was less than 50%, there were also far fewer rotten bolls, and the yield reduction was lighter. This painful lesson is especially worth summarizing.

At present, this is the critical period for autumn sowing production. Major cotton-producing regions in various places can reform planting methods in combination with @#@245@#@ and the sowing and transplanting of rapeseed. Where full-width wheat sowing or full-width rapeseed sowing (transplanting) is practiced, the planting method should also be reformed immediately after the wheat and rapeseed harvest, advocating wide rows (row spacing 1.2 m) with dense plants (plant spacing 0.4 m) and equal rows (row spacing not less than 1 m) with expanded plant spacing (plant spacing 0.45-0.5 m). Wide-narrow row and square block arrangement planting are not suitable, and the narrow-row dense-plant planting of conventional cotton should certainly not continue to be used. The planting density should preferably be 1300-1500 plants per mu, and each place should proceed from local realities and may make appropriate adjustments. For example, in plain cotton regions with better soil fertility and a higher fertilization level, the planting density may be appropriately reduced, while in hilly areas, sloping land and cotton regions with a lower fertilization level, the planting density may be appropriately increased.

Reforming the cotton planting method, first, helps save labor for transplanting cotton, especially for large cotton growers, making it easier to save labor and expenses, because at present the young and strong labor force in rural areas has basically gone out to work, and those remaining are mostly old and weak laborers; second, the winter crop seedlings are small and the climate is relatively dry, which is conducive to reforming the planting method; third, it helps with turning and preparing the cotton rows in winter and spring, so that the reserved cotton rows achieve loose soil and clean weeds, reducing overwintering pests; fourth, it helps with cotton field land preparation, fertilization, transplanting cotton seedlings, and opening ditches for drainage; fifth, it helps with the operational management of intertillage and hilling after cotton planting, ridging and raising the rows, and pest and disease control; sixth, it helps with ventilation and light transmission between cotton rows, improving photosynthetic efficiency, reducing rotten bolls, and improving cotton quality. As long as the reform of the planting method takes a big step forward, it can create good ecological conditions for the survival of cotton. With sufficient space for cotton to stretch out fully, it can lay a relatively solid foundation for high yield and good quality.