Synergistic Effect of Mixture of Microsporidium Nosema locustae (Protista: Microsporidia) and Novel Fungus Aspergillus oryzae XJ-1 (Eurotiales: Trichocomaceae) Against Adult Locusta migratoria (Orthoptera: Acrididae) in Laboratory

Abstract

Locust adults can form gregarious swarms and cause locust plagues. Few studies have evaluated the efficacy of a mixture of two biocontrol agents for controlling locust adults. Here, we assessed the effects of the mixture of a protozoan biocontrol agent, Nsoema locustae, and a fungal agent, Aspergillus oryzae XJ-1, at two ratios against locust adults in the lab. Synergistic effects of the mixture were observed (χ2 > χ2 (df, 0.05) and Po > PE). The maximum mortality caused by an N. locustae–A. oryzae XJ-1 mixture was 92.67% on the 12th day after inoculation, much higher than those of each agent. In addition, the median survival times were significantly lower when locusts were exposed to the mixture than when they were exposed to N. locustae or A. oryzae XJ-1 alone (p < 0.05).