INTERNATIONAL JOURNAL OF AGRICULTURAL TECHNOLOGY

Volume 18, No. 01, Month JANUARY, Year 2022, Pages 257 - 270

Lethal effect of native metarhizium rileyi (farlow) samson isolate to invasive fall armyworm, spodoptera frugiperda (j.e. smith), infesting corn in the philippines

Montecalvo, M. P., Navasero, M. M. and Navasero, M. V.

Abstract Download PDF

Detection of fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), in the Philippines in 2019 prompted research on pest management solutions aside from insecticide application. This paper presents the bioefficacy of an entomopathogenic fungus in controlling S. frugiperda. A native Metarhizium rileyi Farlow (Samson) was successfully isolated from naturally infected S. frugiperda larvae collected in a corn field in Lucena, Quezon province in the Philippines. Laboratory bioassays were conducted to elucidate the virulence of M. rileyi to different life stages of S. frugiperda. Based on t-test, M. rileyi had no ovicidal activity. The larval instars of S. frugiperda were susceptible to M. rileyi with higher mortalities in early instars. Mycosed larvae were covered with white fungal growth and light olive green conidia. The mean time to larval death ranged from 5.10 to 8.67 days depending on conidial concentration and larval instar while lethal concentration (LC 50) was computed from 7.30 x 105 to 3.81 x 1013 conidia/ml. Based on t-test, reduced pupation and adult emergence were observed in fungal treated prepupa. However, there was no effect on the adult emergence of fungal treated pupa. Virulence of M. rileyi to S. frugiperda implies its potential use and integration in the Integrated Pest Management for S. frugiperda in the Philippines.

Keywords

Biocontrol, Pest management, Fall armyworm

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