晚播小麦高产的主要限制因素

１９９１～１９９３年在临汾市乔李村采用大田调查与小区试验相结合的４因素３水平正交法，研究晚播小麦高产的主要限制因素。结果，４种限制因素的效应次序为：施氮时期及比例＞施纯氮肥量＞基本苗＞播期。３年大田调查，晚播小麦在合理施肥的条件下，亩产仍可达到５００ｋｇ。因此，晚播小麦高产的主要限制因素是施氮时期及比例，而不是冬前积温。

Main Limiting Factors of High Yield on Late Sowing Wheat

The experiment was done at Qiaoli, Linfen City in the years from 1991 to 1993 by combining field investigation with plot test. Main Limiting factors of high yield on late sowing wheat were studied by using orthogonal method of four factors and three levels. The result showed that the magnitude order of the limiting factors was: date of nitrogen fertilization and proportions > application rate of nitrogen fertilizer > sowing rate> sowing date. The field investigations for three years showed that the yield of late sowing wheat may reach up to 500kg/mu by appropriate use of fertilizer. The main factors limiting high yield of late sowing wheat hence are the date of nitrogen fertilization and proportions rather than accumulated. temperature before winter.