花生根结线虫病产量损失估计与防治指标的研究

1990—1992年采用池栽与田间考查相结合的方法,研究了花生根结线虫的为害与产量损失率之间的关系及其防治指标。结果表明,土壤中线虫初始密度的对数值与花生荚果产量损失率及病情指数之间的关系均符合logistic曲线;而病情指数、收获前土壤中的线虫密度与花生产量呈显著负相关。得出防治指标为:中等产量水平的田块中播种前每kg土壤中含有侵染期幼虫和卵31.14条(粒)。

ON THE DAMAGE AND ACTION THRESHOLD OF NORTHERN ROOT-KNOT NEMATODE TO PEANUT

In 1990-1992, some cement pit plot experiments and field investigations were conducted for exploring the relationship between the damage of northern root-knot nema-tode Meloidogyne hapla Chitwood and yield loss rate of peanut and the action threshold of this nematode in peanut field. The results showed that the yield loss rate of pod and damage index of peanut increased according as logistic curve with the logarithms of the initial namatode densities in soil, and the damage index and density of nematode in soil before harvest were significantly and negatively correlated to peanut yield. The action threshold of M. hapla to peanut in middle fertility level before sowing was derived as 31. 14 infective larvae and eggs per kg of soil.