种植密度与施肥量对小麦抗倒伏性能的影响

Effects of Planting Density and Fertilizing Amount on Wheat Lodging Resistance

为明确小麦抗倒伏能力与种植密度(Z)、施氮量(N)、施磷量(P)、施钾量(K)间的关系,并为完善小麦高产栽培理论提供参考,以倒伏指数作为评价小麦抗倒伏能力的指标,通过四元二次旋转设计试验,研究了倒伏指数与茎秆机械强度、鲜重、重心高度间的相关性,并建立了倒伏指数与Z、N、P、K的回归方程。结果表明:倒伏指数与茎秆机械强度(-0.826**)相关性最大,其次为茎秆鲜重(-0.489**),均呈极显著负相关;四个因素对倒伏指数的影响程度为施钾量(88.921)>种植密度(77.061)>施氮量(38.639)>施磷量(3.736);倒伏指数与四个因素均成二次曲线关系,表现为随着种植密度增大,倒伏指数逐渐增大,但增速逐渐变缓;随着施氮量与施钾量增加,倒伏指数先增加后缓慢减小,随着施磷量增加,倒伏指数先缓慢增加后迅速增加。

To make sure the relations of wheat lodging resistance with planting density（ Z）,nitrogen amount（ N）,phosphorus amount（ P） and potassium amount（ K） and to provide references for completing the high- yielding cultivation theory,the correlations of lodging- resistant index with stem mechanical strength,fresh weight and gravity center height were researched by an orthogonal rotational regression combination design of 4 factors. The regression equations were constructed for lodging- resistant index with Z,N,P and K.The results showed that the stem mechanical strength showed the maximum correlation with lodging- resistant index,and the next was stem fresh weight. They both had very significantly negative correlation. The influence degree of the 4 factors was K（88. 921）〉 Z（77. 061）〉 N（38. 639） 〉P（3. 736）. The lodging- resistant index showed quadratic curve relationship with any one of 4 factors. With the increase of planting density,the lodging- resistant index increased gradually with slower and slower speed. With the increase of N and K application rates,the lodging- resistant index increased firstly and then decreased slowly. And with the increase of P application rate,the lodging- resistant index increased slowly at first and then rapidly.