Seasonal Occurrence of Tobacco Caterpillar, Spodoptera litura in Urdbean Under Rice Fallows

摘要

Urdbean [Vigna mungo (L.) Hepper] is an important pulse crop grown in India. In Andhra Pradesh, the crop is largely cultivated in rice fallows during Rabi (November-March) as a relay crop in Krishna, Godavari and North Coastal zones and to some extentduring Kharif and summer seasons in other parts of the state. Damage due to insect pests is one of the major production constraints of which the tobacco caterpillar, Spodoptera litura (Fabricius) (Noctuidae: Lepidoptera), is an economically important and regular pest on a wide range of field and horticultural crops causing severe losses. The pest mainly feeds on leaves during the vegetative stage, but the grownup larva also damages the reproductive fruiting bodies. Pheromone baited traps are widely used for monitoring pest populations of S. litura (Mishra and Sontakke, 1992). Rao and Subbaratnam (1999) observed the moth activity of S. exigua from the last week of November until the third week of February in onion growing areas of Guntur district. While, Sreenivasulu et al., (2003) observed peak male moth catch of S. litura in sex pheromone traps during the 2nd week of February on groundnut during Rabi 2000 in Tirupati. Syobu et al., (2003) suggested that besides injury by young larvae in soybean leaves, a prominent increase in pheromone trap catches provide useful information for taking control decisions. Therefore monitoring of male moths of S. litura was taken up using sex pheromone lures in rice fallow urdbean during the Rabi seasons of 2009 and2010 at Agricultural Research Station, Ghantasala, Krishna District, Andhra Pradesh.