Current status of the invasive pest (Tuta absoluta) and other pest complex on tomato crop in Karnataka

Tomato is one of the commercially important vegetable crops in India. Recently, an invasive pest Tuta absoluta was introduced to India causing potential yield loss to the tomato crop. Several studies were undertaken on the pest since 2014 to understand the biology, distribution, host range, natural enemies and chemical management of the pest. It is important to understand the current status of the pest at regular time intervals to validate the existing practices and to development suitable management technologies. Thus, current study aims at understanding the spatial variation in the pest incidence in randomly sampled 24 tomato fields in larger tomato growing areas viz., Chikkaballapur and Kolar of southern parts of Karnataka from August to December, 2018. There was no recognizable pattern in spatial distribution of the pest damage on the crop vegetation and the fruit yield. Intensity of pest incidence on different plant canopies as well as fruit yield were observed to be very low to low (0 – 20 per cent) in 70 per cent of the sampled locations. Subsequently, less than 10 per cent of locations showed high pest infestation. Further, in all the locations, 10-22 per cent of yield loss was observed to be due to insect pest, diseases and/or nutritional deficiency in the sampled locations. In the total loss incurred, about 50 percent of the damage caused by the incidence of Tuta absoluta alone. Further studies have to be conducted on the effect of biotic and non-biotic factors on the pest population, effect of prevailing management practices on the natural enemies to understand the current status of the pest in different seasons.