关键词: 棉花, 集中成熟, 高效群体, 优化成铃, 高效脱叶, 栽培技术

Abstract:

Concentrated maturation is the basic requirement of cotton mechanical harvesting, referring to the phenomenon that bolls of the whole cotton plant complete opening in a relatively short period of time. Concentrated maturation cultivation refers to the cultivation management technique and measure for achieving optimized fruiting and grouped maturation in cotton. After many years of research and practice, the theory and technology of centralized maturation cultivation of cotton in China have been established, becoming an important approach of modern cotton farming theory and technology. The concept and connotation, key regulatory technologies and the eco-physiological mechanisms of cotton concentrated maturation were innovatively highlighted and reviewed in this paper. The cultivation and regulation for cotton concentrated maturation should start from sowing. The precision monoseeding technology assured well-established strong seedlings, which created a solid basic population for realization of concentrated maturation. Based on good stand establishment, irrigation, fertilization and plant growth regulators were comprehensively used to regulate the growth and development of plant individuals and populations to construct the ideal plant type and the efficient population structure according to local ecological conditions and production conditions, and finally realize the optimized spatiotemporal distribution and concentrated opening of cotton bolls. Precision monoseeding created a suitable soil pressure to seedlings during emergence and a dark environment before emergence, and induced expression of apical hook formation- and hypocotyl elongation-related genes, which promoted hook formation and hypocotyl growth and seedling emergence. The seedlings under monoseeding had independent growth space after emergence, which had little mutual influence and were easy to establish strong seedlings. Close-planting and chemical control inhibited the photosynthesis of leaves sourced from vegetative branches, and altered the content and distribution of endogenous hormones through changing the expression of key genes of hormone metabolism, which regulated the vegetative branching and apical growth of main stems, and finally realized non-pruning and promoted concentrated boll-setting. Leaf-derived jasmonic acid induced by partial root-zone irrigation, as a long-distance signal transported through the phloem to the irrigated root side, promoted the expression of aquaporin gene, and then improved the capacity of water absorption and water use efficiency. The partitioning of assimilates to cotton bolls and the defoliation rate were significantly improved by fertigation under partial root-zone drip irrigation. In this case, reduced inputs of water and fertilizer as well as significant reduction in heterozygosity in machine harvested seed cotton have been achieved without yield loss. The theory and technology of cotton concentrated maturation cultivation was a new achievement of cotton cultivation research in the new era, and an important scientific and technological support for the development of modern cotton industry. In order to provide a more powerful theoretical and technical support for light and efficient cultivation of cotton in the future, on the one hand, in-depth study is required to reveal the physiological and ecological mechanisms of concentrated maturation. On the other hand, it is necessary to innovate the key cultivation techniques, and to develop the well-matched varieties and agricultural mechanic equipment for their better integration. It is also necessary to strengthen the combination of agronomic technologies with smart agricultural technology, so as to provide a more powerful theoretical and technical support for concentrated maturation cultivation of cotton.

Key words: cotton, concentrated maturation, high-efficiency population, optimization of boll-setting, high-efficiency defoliation, cultivation technology