Sampling Methods and Mass Trapping of Onion Thrips on Onion Crop

Using different sampling methods is helpful in the survey of insect fauna of onion and to provide an understanding of onion thrips, Thrips tabaci in relation to cultivars and biotic and abiotic factors. Thirty six insects and spiders belonging to 17 families and 10 orders are associated with onion cultivars. Early detection and monitoring of T. tabaci could be done by using sticky trap or plant sampling. Abiotic factors (temperature and relative humidity) are the major influencing factors that regulate the population growth. Natural enemies and other insect pests of onion are non-significantly related with T. tabaci in field condition. Blue sticky trap and plant sampling are the best methods to determine the level of infestation. Economic threshold level could be determined by sticky traps, but it needs more investigation. Sticky traps could not be used in the management of thrips on onion crop but only for monitoring thrips.