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应用距平值法和方差分析法,对我国1978—2007年的粮食单产增加原理进行了分析。结果表明,我国粮食单产呈周期性增加规律,粮食单产周期性增加是作物品种周期性更新的结果,作物品种最高产量施肥量是品种的重要营养遗传特性,是品种适应土壤环境条件的结果。因此,肥料施用量的周期性增加是作物品种更新的重要原因。近30年来,我国作物品种潜力水平的提高,主要是利用了育种材料的耐氮肥特性,而没有利用品种营养平衡的遗传特性,结果导致单位肥料的增产量逐年降低。
The principle of increase of grain yield per unit of output in 1978-2007 in China was analyzed by means of anomalous value method and analysis of variance. The results showed that the grain yield increased cyclically in our country. The cyclical increase of grain yield was the result of cyclical renewal of crop varieties. The highest yield and fertilizer amount of crop varieties was the important nutritional and genetic characteristics of cultivars, which was the result of adapting to the soil environmental conditions. Therefore, the periodic increase of fertilizer application is an important reason for the crop variety renewal. In the recent 30 years, the potential of crop varieties in China has been improved mainly because of the use of the nitrogen-resistant characteristics of breeding materials, without the genetic characteristics of nutritional balance. As a result, the yield per unit of fertilizer has been reduced year by year.