Parametric Survival Functions to Measure the Effectiveness of Metarhizium neoanisopliae and Metarhizium sulphureum against the Brown Planthopper

This article evaluates the effectiveness of two Metarhizium neoanisopliae strains (ARSEF7487, BCC4849) and five Metarhizium sulphureum strains (BCC12791, BCC18130, BCC36572, BCC36592, BCC39045) against the brown planthopper (BPH), a major rice pest. A survival analysis was conducted using four parametric survival functions: Weibull, log-normal, gamma, and log-logistic, with the best-fitting models determined by the Akaike and Bayesian information criteria. Additionally, the goodness-of-fit was tested using the Kolmogorov–Smirnov, Anderson–Darling, and Cramer–von Mises tests. Results indicated that the log-normal distribution provided the best overall fit for the data. Among the tested strains, Metarhizium neoanisopliae strain BCC4849 showed the highest mortality rate of 79.99 $$\%$$ , followed closely by Metarhizium sulphureum strain BCC36572 with 67.10 $$\%$$ mortality. The log-rank test confirmed that these two strains did not significantly differ in efficacy under the same experimental conditions. These findings suggest that Metarhizium neoanisopliae strain BCC4849, along with Metarhizium sulphureum strain BCC36572, could serve as highly effective biological control agents for managing BPH populations, offering a sustainable alternative to chemical insecticides.