Biochemical and Morphological screening of cotton (Gossypium hirsutum L.) hybrids for Jassid resistance (Amrasca biguttula)

The cotton hybrids of seven lines (BSH 18, MCU 5, CO 14, TCH 1828, CO 17, TCH 11199 and Suraj) and five testers (KC2, KC3, GISV 323, GTHV 15–34 and RHC 1409) were raised inRBD for obtaining 35 hybrids. The hybrids along with their parents were studied for traits viz. , mean number of Jassids per plant, injury grade, total phenol content, total reducing sugars, total soluble proteins, trichome length, trichome density and chlorophyll index along with the seed cotton yield per plant. Higher phenolic content, lower reducing sugar, lower soluble proteins, greater chlorophyll index, and higher trichome density would result in fewer jassids per plant. MCU 5 X KC3 hybrid had the lowest injury grade (0.13), highest total phenol content (3.84 mg/g), lowest total reducing sugars (1.14 mg/g), highest chlorophyll index (58.33), lowest trichome length (0.43), highest trichome density (271.42 numbers per centimetre square) and highest yield of 150.74 g/plant. Hence this F ₁ hybrid confers resistance against jassids. Hence, higher phenolic content along with higher trichome density offers resistance to jassids in cotton plants. This cross could be further forwarded to F ₂ to identify the jassid segregants for further screening. Thus, knowledge into these biochemical analyses and trichome density of the cultivar might be used to breed for jassid resistance, which would assist minimise the usage of pesticides and pest loads from the fields, thereby increasing the population's productivity.