Virulence and trans-generational effects of Metarhizium anisopliae on Oxycarenus hyalinipennis.

Abstract

Insect pests cause major yield losses to Gossypium hirsutum, which often require the use of chemical insecticides. To avoid human health, environmental and resistance problems, entomopathogenic fungi (EPF) can be used for controlling insect pests. In our study, the pathogenicity of Metarhizium anisopliae to Oxycarenus hyalinipennis was determined by immersion method. Further, the sub-lethal and lethal effects of M. anisopliae on the biological parameters of O. hyalinipennis were investigated by age-stage, two-sex life table software. Metarhizium anisopliae infection was lethal to the 4th instar of O. hyalinipennis with LC50 values of 8.84×104 spores/mL. The sub-lethal and lethal concentrations of M. anisopliae not only affected the parental generation (F0 ) but also the demographic parameters of the offsprings of the filial generation (F1 ). Trans-generational results of F1 infected with M. anisopliae showed decreased net reproductive rate (Ro ), intrinsic rate of increase (r) and mean generation time (T) compared to those of the control group. The larval developmental duration significantly decreased to 15.52 and 19.02 days in the LC50 and LC20 groups, respectively, as compared to 21.08 days in the control group. There was a noteworthy decline in mean fecundity in the LC50 and LC20 groups, i.e., 16.0 and 20.96 eggs, compared to 33.26 eggs in the control group. Adult longevity was likewise considerably reduced in the LC50 and LC20 treated groups. The study showed that M. anisopliae can have an enduring impact on the biological parameters of O. hyalinipennis, which may enhance its use in eco-friendly management programs. This article is protected by copyright. All rights reserved.