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In India, the invasive fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) has emerged as the most devastating pest of maize. Being a polyphagous pest, it feeds on almost 353 host plants and keeps widening its host range. In this study, we assessed the preference for feeding and oviposition in both choice and non-choice scenarios among various host plants such as maize, sorghum, castor, cowpea, cotton, banana and marigold. In choice tests, the number of larvae on maize cob was the most whereas it was the least on cotton leaves, after 24 hours of release. In non-choice study, the third instar larvae fed on maize leaves and cobs had the shortest larval growth periods (2.05 and 2.20 days, respectively), whereas the larvae fed on marigold flowers had the longest (5.20 days) larval growth periods in order to reach the next instar. In oviposition tests, maize supported egg laying to the greatest rate (8.67 egg masses/host in the choice test and 11.67 egg masses/host in the no-choice test) when compared to other hosts under study. The remaining hosts were used by the pest only in the absence of its usual host (maize) for oviposition. Thus, maize was the most suitable host for fall armyworm and it may also be able to survive in crops other than maize during the off-season thus posing a high risk to other economically important crop plants. |
