施肥量与栽培密度对水稻二化螟为害程度的影响

Effect of Application Amount and Planting Density on Damaging Degree of Chilo suppressalis Walker

采用正交区组二次回归旋转组合设计,在大田条件下建立了氮、磷、钾不同施用量及不同栽培密度与水稻二化螟为害关系模型并对模型进行了效应分析。结果表明:施氮量是影响二化螟为害程度的最主要因素,随着施氮量的增加,二化螟为害率呈急剧上升的趋势;适当增施磷、钾肥有利于降低二化螟为害率;合理稀植有利于控制二化螟的大发生;在-1≤Xi≤1范围内,利用二化螟为害率模型,推寻出为害率小于1%的农艺方案,即当施氮量为105～119kg hm2、施磷量为48～90kg hm2、施钾量为90～150kg hm2、栽培密度为12 5～17 9穴 m2时水稻二化螟为害较轻。

By means of the design of orthogonalty, a damage model of Chilo suppressalis walker under different N, P and K application amount and planting density in field was built The analysis on model effect shows that N application amount has the closest connection with the damage rate of Chilo suppressalis walker The more N is applied, the higher the damage rate is To increase properly the amount of P and K fertilizers can decrease damage rate Proper thing planting can greatly benefit the control of Chilo suppressalis walker With the damage rate model within -1≤Xi≤1, an agricultural project on damage rate under 1% can be calculated Damage is light when application amount of N, P and K is 105～119 kg/hm2, 48～90 kg/hm2 and 90～150 kg/hm2 respectively, and planting density is 125～179 hole/m2