ACCELERATING INFESTATION OF PINK BOLLWORM PECTINOPHORA GOSSYPIELLA (SAUNDERS) (LEPIDOPTERA: GELECHIIDAE) ON BT–VARIETIES OF COTTON INPAKISTAN

Bt cultivars of cotton worked satisfactorily for last many years except some limited and short duration problems of bollworms reported from different pockets, that were usually because of mixed seed. In last cotton season 2014, pink boll worm Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) intensified cotton crop tremendously and it was reported from almost all the cotton growing tract of Punjab. Owing to these reports, present studies were carried out in three subdivisions/tehsils of Lodhran district (Kehror Pacca , Dunya Pur and Lodhran) on 17 different Bt-varieties/lines of cotton (A-777, BS-52, Bt-312, Bt-252, Bt-616, Eagle-1, IUB-2013, MNH-992, NIAB-999, SG-1, A-555, CEMB-666, FH- 142, IUB-222, Lalazar, MNH-886 and MNH-988). Fifty bolls were plucked randomly from all the fields. The varying number of samples of cotton bolls (50 bolls from each variety) were collected for consecutive 15 days (20th October to 5th November, 2014) from different cotton cultivars grown at farmer s fields in Kehror Pacca (11 samples), Dunya Pur (10 samples) and Lodhran (9 samples) sub-divisions. In total 1549 collected bolls were kept in paper bags for a week and then percentage of damaged bolls as well as number of live larvae were recorded from all samples. The results were alarming to note that all of 17 cultivars/lines were susceptible showing maximum infestation of 24.49% to 100%. The average intensity of alive larvae per boll was 109.6 % (1698 larvae in 1449 bolls collected for study) inside the infested bolls. The situation spells a serious threat and demands the immediate attention of cotton growers, breeders, biotechnologists, seed producers, extension workers, entomologists and research workers.