SCREENING FOR SUCKING PESTS (THRIPS AND JASSIDS) SCREENING FOR SUCKING PESTS (THRIPS AND JASSIDS) RESISTANCE/TOLERANCE IN COTTON GERMPLASM LINES ANCE/TOLERANCE IN COTTON GERMPLASM LINES (GOSSYPIUM HIRSUTUM L

Abstract

During 2011-12 although the experiment was conducted under protected condition the presence of large phenotypic variability for jassids reaction was noticed, therefore observations are made on jassids damage and identified jassids resistant, tolerant and susceptible germ plasm lines. Selected germplasm lines were taken up during 2012-13 by evaluating in protected and unprotected conditions. Identification of resistant and susceptible germ plasm lines for thrips and jassids are carried out based on biochemical and average pest load/ leaf. Under protected condition experimental mean of thrips load was 1.70/leaf and in unprotected condition mean thrips load was 6.91/leaf. Highest mean value for phenols is observed on SEC-6 (4.21 mg/g) and lowest on RDT-31 (1.98 mg/g) in protected conditions and in unprotected conditions highest mean value observed on SEC-6 (3.12 mg/g) and lowest mean value on RDT-1 (1.35 mg/g). Mean of the germ plasm lines for reducing sugar content was 2.41 mg/g and 3.57 mg/g in protected and un-protected conditions respectively. Mean of the germ plasm lines for gossypol content was 31.73 μg/g and 28.72 μg/g in protected and un-protected conditions respectively. CPD1015 identified as resistance to thrips, SEC-6, FQT-36 show resistance to jassids and CPD-1015 recorded as resistant to both jassids and thrips.