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不同行距引起大豆生长竞争。当某一因子的直接供应不能满足群体生长的需要而成为限制因子时 ,竞争便开始。本文主要从基因型、光、水、养分和杂草等 5方面综述过去 4 0年行距变化对大豆竞争资源的影响。研究表明 ,不同品种对行距变化的反映不同 ,其依赖于季节降雨和灌溉。有限结荚习性类型可获得较高产量 ,抗倒伏的大豆品种适于窄行种植。无限结荚习性大豆在一定的行距条件下也可获得最佳产量。与宽行大豆种植相比 ,窄行大豆栽培增加光截获 (LI) ,其原因在于LAI、消光系数的增加及分枝类型品种的选择。水分利用效率和蒸发蒸腾作用不受行距影响 ,但在灌溉条件下产量增加。行距变化对养分吸收影响较大 ,随着行距的减小 ,植株产量和N、P、K的吸收均增加 ,且增加幅度受施肥水平制约。行距不影响N素的固定。行距不影响杂草密度、萌发高峰及持续时期 ,但在窄行栽培条件下可减少杂草的数量及干重 ,再配以适量的除草剂可获得良好的除草效果。不同行距条件下的大豆生理反应、养分和水分的吸收及转运 ,不同冠层的光能利用以及土壤环境的变化仍需进一步深入研究。
Different row spacing caused soybean growth competition. When the direct supply of a factor can not meet the needs of population growth and become a limiting factor, competition begins. In this paper, the effects of changes in row spacing on the competitive resources of soybean in the past 40 years were summarized from five aspects of genotype, light, water, nutrients and weeds. Studies have shown that different varieties reflect different changes in row spacing, which depend on seasonal rainfall and irrigation. Limited pod habit types yield higher yield, and lodging resistant soybean varieties are suitable for narrow row planting. Unlimited Soybean Soybean yields the best yields at a certain spacing. Compared with broad-leaved soybean planting, narrow-row soybean cultivation increased light interception (LI) due to LAI, increase of extinction coefficient and selection of branching type varieties. Water use efficiency and evapotranspiration were unaffected by row spacing but increased under irrigation. Changes in row spacing had a great effect on nutrient absorption. With the decrease of row spacing, plant yield and absorption of N, P and K increased, and the increase range was restricted by fertilization level. Line spacing does not affect the N-fixed. Row spacing did not affect the density of weeds, the peak of germination and the duration, but we could reduce the quantity and dry weight of weeds under the narrow row cultivation conditions, and then get the good herbicidal effect with proper amount of herbicides. Physiological responses to soybean at different row spacing, absorption and transport of nutrients and water, utilization of light energy in different canopies and changes in soil environment still need to be further studied.