20%甲胺·氰乳油防治棉铃虫的一种田间药效评价方法

A Evaluation Method of Field Trial for Controlling of Ballworm by 20% Methamidophos with Fenvalerate EC

在田间药效试验中，用空白对照同步孵化率，将同期卵数折成虫口基数。在计算保顶效果和保蕾铃效果时，先减去药前受害顶心株数和受害蕾铃数。

During the field test, we convert the eggs into grown-up bollworms. We Consider the number of damaged cotton terminal buds and damaged cotton buds and bolls before using pesticide, when we calculate the protecting rates of cotton buds and bolls. The result is very close to the reality.