POPULATION BUILD UP STUDIES OF SUNFLOWER SUCKING PESTS WITH CHOICE AND NO-CHOICE TESTS ON PROMISING SUNFLOWER LINES

Abstract

One hundred and twelve accessions of sunflower (Helianthus annuus L.) were screened under field conditions in two seasons (Rabi 2016 and Kharif 2017) at Sambavar Vadakarai and Udappankulam villages of Tirunelveli district of Tamilnadu, India. Investigations were made to study the population build-up of sucking pests viz., whiteflies (Bemisia tabaci), leaf hoppers (Amrasca biguttula biguttula) and thrips (Thrips palmi) on sunflower. Results of field screening indicated six accessions  (KBSH-1, K 578, AHT 02, IHT 751, GMU 615, GHU 631) to be comparatively resistant to the sucking pests. The  check variety ‘Morden’ proved to be the most susceptible sustaining highest populations of sucking pests throughout the experimental period. Population build-up studies (Choice-test) on the six promising accessions in comparison to Morden as 'check’, revealed that AHT 02 harboured least population of whiteflies followed by IHT 751 and KBSH-I. The population of leaf hoppers was minimum on K 578 followed by KBSH-1 and AHT 02. The acccessions KBSH-1, IHT 751 and AHT 02 recorded least mean thrips population. Under No-choice test, KBSH-1 and IHT 751 recorded least whitefly population and the accessions K 578 and KBSH-1 sustained  minimum leaf hopper population. The least number of thrips was observed on IHT 751 followed by AHT 02 and KBSH-1.