栽培措施与烟草赤星病抗性关系的研究

Study on the Relation Between the Occurrence Degree of Tobacco Brown Spot and Comprehensive Farming Measures

采用三元二次通用旋转回归组合设计，研究了烟草赤星病病情指数与移栽期、饼肥用量和后期补钾次数之间的量化关系，根据试验结果建立起病情指数与三因素间的数学模型。经检验，该模型回归关系显著，其中移栽期是影响烟草赤星病发生的首要因素。适当早栽，增加饼肥用量和后期补钾次数可减轻赤星病危害。三因素最佳组合为移栽期４月１６～２０日，饼肥施用量３３０～４２０ｋｇ·ｈｍ－２，后期补钾３～４次。经２ａ的田间验证试验，实际值与理论值基本一致。

By applying the commonule combination design of quadyatic regression ,the quantity relation between the occurrence degree of tobacco brown spot and the comprehensive farming measures( replantingtime x 1 ,cake manure x 2 , potassium x 3 )was studied from 1994 to 1996.The results showed that the disease level has close relation with the farming measures and there is interaction among the measures. On the basis of the results above, a mathematic equation of relation has been set up between the disease levels and the farming measures in Xuchang ecological condition.This model could express the relation between the occurrence degree of tobacco brown spot and comprehensive farming measures. It has been verified by two years′ demenstration in many places.