Morphometric Studies of Tobacco Caterpillar, [Spodoptera litura (Fabricius)] on Different Host Plants

Tobacco caterpillar, Spodoptera litura (Fabricius) is an economically important polyphagous pest inflicting significant economic damage to numerous field and horticultural crops. Research was conducted at the Department of Entomology, Bihar Agricultural University, Sabour, Bhagalpur, Bihar, in laboratory settings to validate the presence of this pest. The investigation involved detailed measurements of the various larval stages, pupa, adult male, and female, of tobacco caterpillar including the wingspan. The first to sixth instars of S. litura exhibited significantly greater length and width as well as width of head capsule, when reared on the tomato as a host. The pupae of S. litura reached at their maximum length and width when raised on marigold (16.75 mm and 4.36 mm), while the minimum pupal measurements (14.10 mm and 4.42 mm) was observed in case of maize. In regards to the adult moths, both male and female specimens displayed the longest length and wing span when associated with tomato (16.71 mm and 18.22 mm for length, 38.47 mm and 38.73 mm for wingspan, respectively), whereas the smallest measurements were recorded for those associated with maize (14.35 mm and 16.95 mm for length, 35.10 mm and 35.12 mm wingspan respectively). The present study confirmed the presence of S. litura that require immense attention to prepare the management strategy against it.