摘要
分别研究了品种、施氮量及其互作对早稻纹枯病的影响。结果表明:纹枯病的发展随施氮量的增加而加重,施氮量(N)与病害发展速率比值(RR)关系模型是:RR=1.07899/[1+1.21482EXP(-0.22775*N)]。纹枯病对氮量的灵敏点在每亩施纯氮7.5—12.5公斤内;品种间抗感差异明显,其感病程度可分为三类,各类品种系数可互换;品种与施氮量互作对病情发展影响显著,施氮量对品种抗感性有一定影响,组建了各类品种系数与施氮量关系的数学模型。
Effects of nitrogen fertilizer levels and rice varieties, and their combinations on the development sheath blight on early season rice were quantitatively studied. Results show that the effect of N levels was significant, setting up a model based on the relationship between the N levels and the ratio of disease progress (DP) rate:RR=1.07899/(1+1.21482~■exp(-0.22775~■N))Sensitive point of effect of N levels on DP was from 7.5 to 12.Skg/mu, risistance and susceptibility of various rice varieties differed significantly with the later of 3 ranks; coeffecient of disease index of various types may be exchanged; N. levels combined with rice varieties had a significant effect on DP; N-level effect on resistance and susceptibility of varieties was also apparently observed in the study.
基金
国家"七五"攻关项目
关键词
品种
氮肥
水稻
纹枯病
Rice sheath blight
Variety
Nitrogen fertilizer level
