Test concentrations of Riau local rice field isolate entomophatogenic fungus Metarhizium anisopliae toward mortality brown planthopper (Nilaparvata lugens stal.) in the laboratory

Abstract

The brown planthopper (BPH) (Nilaparvata lugens Stal.) is main pest of rice plants and cause hopperburn and viruses vector. The BPH control uses an entomopathogenic fungus is Riau local rice field isolate Metarhizium anisopliae. This isolate was obtained from rice plants in Kampar, Riau. The research was aimed to get the best concentration and the right concentration in killing the BPH. Research was conducted at Laboratory of Plant Pests, Faculty of Agriculture, Riau University from June to April 2023. The research was conducted experimentally using a completely randomized design (CRD) with 6 treatments and 4 replications. The treatment was concentration of 0, 40, 50, 60, 70 and 80 g.l-1 aquades to obtain 24 experimental units. The parameters for observation were initial time of death, lethal time 50%, lethal concentrations of 50 and 95, daily mortality and total mortality. The results research shows concentration of 40 g.l-1 aquades (0.90 x 106 kon.ml-1) was the best concentration cause a total mortality of 72.50 ± 9.57%, the initial time of death 163.50 ± 6.45 hours after application and lethal time of 50 206.25 ± 9.77 hours after application. The right concentration in killing 50% and 95% of BPHs was 2.11% and 10.45%..