一种估算草地贪夜蛾卵块中卵粒数量的简易方法

草地贪夜蛾Spodoptera frugiperda (Smith)是2019年发现入侵我国的一种重要的外来害虫，对我国粮食种植业造成严重威胁。明确虫情是做好草地贪夜蛾预测预报和制定科学防控策略基础。在田间调查中需要一种简便、快速估计落卵量的方法，以明确田间虫口数量。本研究在实验室条件下收集草地贪夜蛾雌虫产于玉米叶片上的卵块，记录了每个卵块的长、宽、层数和卵粒数量，获得了卵块面积，建立了卵粒数量与卵块面积的指数函数模型：Y=e(2.1596×0.00832X)，并依据该模型提出了根据卵块面积测算卵粒数量的分级表。该方法为田间调查中卵块卵粒数量量的快速估计提供了参考。

A method for estimating the number of Spodoptera frugiperda (Smith) eggs per egg mass

The fall armyworm Spodoptera frugiperda (Smith) was an important new invasive pest, which was found to infest in China in 2019, and would cause a serious threat to Chinese crop production. To clear the occurrence of S. frugiperda in the fields is the basis of its scientific prediction and controlling. In field surveillance for the moth, a rapid and simple method to estimate the number of eggs at crops is needed. The study analyzed the length, width, tier and number of eggs per egg mass that S. frugiperda females laid in corn leaves in lab condition, and calculated the area of the egg mass. The exponential function model between the egg mass area and number of eggs per egg mass was established as Y=e(2.1596+0.00832X). The standard to calculate the number of eggs through the egg mass area data was also proposed based on the above model. The result can provide a reference for rapid estimation of number of eggs per egg mass in field investigation.