The present experiment was conducted at a constant temperature of 25 ± 0.5 °C, 70 ± 5 per cent relative humidity and 14L: 10D photoperiod on French bean, Phaseolus vulgaris cv. contender plants in the Biocontrol Laboratory of the Department of Entomology, Dr YS Parmar University of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh, India. The study revealed that Encarsia formosa exhibited a Type II functional response both on the bases of parasitism and host kill with third and fourth nymphal instars of greenhouse whitefly. The functional response parameters i.e. handling time (Th), attack rate (a), effectiveness of parasitoid (a/Th) and the maximum parasitization rate (K) on total host kill by the parasitoid on third nymphal instar was 0.575 h, 0.037 h⁻¹, 0.064 and 41.684, respectively whereas with fourth nymphal instar, handling time (Th), attack rate (a), effectiveness of parasitoid (a/Th) and the maximum parasitization rate (K) was 0.518 h, 0.044 h⁻¹, 0.086 and 46.317, respectively. The area of discovery of the parasitoid with third nymphal instars decreased from 0.12 to 0.09 and with fourth instar it decreased from 0.14 to 0.09 with the increase in the density of the parasitoid from 2 to 8 for both the nymphal instars (third and fourth), respectively. The mutual interference coefficient with fourth instar was highest (m = 0.285) as compared to third instar nymphs (m = 0.166). It shows its effectiveness against the greenhouse whitefly. Hence, it can be utilized as one of the component of an integrated pest management programme of greenhouse whitefly, T. vaporariorum under protected cultivation.

本实验是在 25 ± 0.5 °C 的恒温、70 ± 5% 的相对湿度和 14L:10D 光周期下对法国豆（Phaseolus vulgaris cv.）进行的。昆虫学系生物防治实验室的竞争植物，YS Parmar 博士园艺和林业大学，Nauni，Solan，喜马偕尔邦，印度。研究表明，Encarsia formosa在寄生和宿主杀死的基础上，温室粉虱的第三和第四若虫表现出 II 型功能反应。功能响应参数，即处理时间（Th），攻击率（a），寄生蜂的有效性（a / Th）和寄生蜂对三龄若虫的总宿主杀死的最大寄生率（K）分别为0.575 h，0.037 h ^-1 , 0.064 和 41.684，而对于四龄，处理时间（Th），攻击率（a），寄生蜂的有效性（a / Th）和最大寄生率（K）为0.518 h，0.044 h ^-1，分别为 0.086 和 46.317。三龄若虫的发现面积从 0.12 减少到 0.09，四龄的发现面积从 0.14 减少到 0.09，随着若虫的密度从 2 增加到 8，对于若虫（三龄和四龄），分别。与三龄若虫（m = 0.166）相比，与四龄的互干扰系数最高（m = 0.285）。它显示了它对温室粉虱的有效性。因此，它可以用作温室粉虱T综合害虫管理计划的组成部分之一。保护栽培下的蒸笼。