Morphological and biochemical responses of cotton cultivars against thrips infestation

Abstract

Thrips damage can affect the morphological characteristics, photosynthetic pigments and biochemical parameters of cotton cultivars. In the pot experiment conducted at RRS, Faridkot, two contrasting cotton cultivars (LH 2107 and LD 491) were infested with thrips after 30 days of sowing. Leaf samples of control and infested plants were collected from 15days post infestation (DPI) at 10 days interval. The highest thrips intensity (38.9 mean thrips/3 leaves) was found in LH 2107 at 90 DAS. Resistant cultivar (LD 491) showed more number of non-granular and glandular trichomes as compared to susceptible cultivar (LH 2107). Correlation analysis of LH 2107 revealed positive correlation of thrips population with reducing sugars, total soluble sugars and total protein. On the other hand, association studies for LD 491 showed that thrips intensity was positively correlated to gossypol, lignin and cellulose. The present study suggests that changes in morphological and biochemical attributes provide resistance against thrips in cotton cultivars. Hence, such attributes can be used as potential markers for developing thrips resistance in cotton through breeding programme.