Prevalence of strain (R and C strains) of fall armywormSpodoptera frugiperda in eastern India

Abstract

An invasive alien pest, fall armyworm has been recently introduced to India. To date, two strains of FAW have been documented, viz. R strain (rice) and C strain (corn) without any clear biological attributes, even though differences are evident. A survey was conducted during 2020–22 over 18 field visits across the eastern part of India (Bihar, West Bengal, Orissa and Jharkhand) to isolate the genetic diversification of FAW populations collected from maize. This investigation was done with a mitochondrial-based ‘universal primer’ using mtCOI (mitochondrial cytochrome c oxidase subunit I) sequence analyses revealed that both strains (R strain and C strain) were present with the FAW. Interestingly, our comprehensive analysis indicates the dominance of the R strain over the C strain in the sample collected from the eastern part of India. This would be the first report from the eastern part of India, mainly the regions of Bihar, West Bengal, Orissa and Jharkhand, where FAW primarily feeds on maize. This study generates an idea about a probable incursion by a genetic asset of FAW in India, which needs dissection of the haplotype.

Keywords

• C strain, Eastern India, Fall armyworm, mtCOIR, Strain, S. frugiperda