Entomology, Ornithology & Herpetology: Current Research
Open Access

Abstract

Relative Performance of Bt-Cotton Hybrids against Sucking Pests and Leaf Reddening under Rainfed Farming

Nagrare VS, Deshmukh AJ and Bisane KD

Bt-cotton currently occupies over 93% of the area under cotton cultivation. Genetic makeup of the plant is very much important to confer tolerance to biotic and abiotic stress under natural conditions. In India, introduction of Btcotton involving several hybrids, most of which were highly susceptible to sucking pests has resulted in increased crop damage. Fifty four Bt-cotton hybrids were evaluated for genetic tolerance to sucking pests and leaf reddening under rainfed farming. Data on population counts were recorded at weekly intervals, leaf reddening at 108 DAS and yield at the end of season. The study revealed Ankur 3070 BG II, Durga BG, Atal BG II, Krish BG II, Ryan BG, Madhura BG, MRC 7301 BG II, SP 504 BG II, Namskar BG II, Mahi BG II, VICH 312 BG II, Ankur 3028 BG, Anvitha BG, VICH 304 BG II, Ankur 3034 BG II, VICH 311 BG II, Ankur Jai BG II, Ankur 216 BG II, Ankur 3042 BG II, Vanaja BG, VICH 301 BG II, Classic BG II, Bunny BG II, Menaka BG II, VICH 314 BG II, Veda 2 BG II, VICH 303 BG II were tolerant to leafhoppers. No significant difference in whitefly population was recorded across the Bt-cotton hybrids. Ankur 2104 BG II, Atal BG II, Madhura BG, Mahadev BG II, Anvitha BG, Mahi BG II, VICH 313 BG II,VICH 301 BG II, Kohinoor BG, SP 504 BG II, VICH 311 BG II, Krish BG II, Aadhar BG, Vanaja BG, Dyna BG II, Ankur 3070 BG II, Namskar BG II, Ishwar BG, Ryan BG, Bunny BG II, Superman BG II, MRC 7301 BG II, Ankur 257 BG II, Durga BG, Shrimanth BG, Classic BG II, Ankur 3034 BG II, VICH 312 BG II, Express BG II, Manjeet BG II, MRC-7383 BG II, Ankur Jai BG II, Menaka BG II, ALTO BG II, RCH 530 BG II, Ankur 3042 BG II, VICH 303 BG II, JKCH 99 BG harbours lowest thrips population. Bt-cotton hybrids JKCH 99 BG, Ankur 3042 BG II, Menaka BG II, Mahadev BG II, Classic BG II, VICH 301 BG II, Ankur Jai BG II, Madhura BG, Veda 2 BG II and Ryan BG indicated tolerance to mirids. Ankur 3042 BG II, Ankur Jai BG II, Classic BG II, Madhura BG, Menaka BG II, Ryan BG and VICH 301 BG II were found tolerant to all the three sucking pests under study. Atal BG II, Ankur Jai BG II, MRC 7301 BG II, VICH 303 BG II, Ankur 216 BG II, Ankur 3042 BG II, VICH 304 BG II, Paras Krishna BG II, Uttam BG II, Express BG II were free from leaf reddening. Highest yield (Kg/ha) gainers were MRC 7301 BG II (1955.48), Krish BG II (1779), RCH 530 BG II (1765), Atal BG II (1741), Bunny BG (1666), Uttam BG II (1638), Classic BG II (1594), Shrimanth BG (1590), ALTO BG II (1583), Krishna BG II (1562) and Ryan BG (1539). The results from this study provide an option for cotton stakeholders to choose tolerant hybrids so that indiscriminate insecticide sprays can be reduced.