Field evaluation of UASD Bt-cotton Event-78 based early segregating generations for cotton leaf hopper

Abstract

UASD Bt cotton Event-78 based early segregating generations (F2 & F3) derived from three diverse crosses were evaluated for field incidence of cotton leaf hopper during kharif-2021 & 2022 at Agricultural Research Station, UAS, Dharwad. A total 600 F2 plants from the crosses viz., UASD Bt-78 х DHS-29, UASDBt-78 х Suvin and Suvin х UASD Bt-78 were screened of which 103,100 and 102 plants respective to the three crosses were found to be resistant. The segregation of F2 population for the jassid tolerance deciphered the implicit “Inhibitory epistasis” mechanism of host plant resistance. Further evaluation of F3 families of these crosses leads to identification of 103 resistant lines from all the three crosses, the mean leafhopper population ranges from 0.67- 2.67 leafhoppers / 3 leaves with the LHRI score of 1.

Keywords

• segregating generations
• cotton leaf hopper
• inhibitory epistasis
• host plant resistance