Studies on biochemical basis of resistance against Scirpophaga incertulas (Walker) in different rice accessions

The chlorophyll content among the selected rice accessions ranged from 2.43 to 8.98 mg/g. The utmost chlorophyll content was observed on susceptible accession TN-1 (8.98 mg/g) followed by BA-270 (7.56 mg/g) and BPT-5204 (7.01 mg/g). Though, 2.43 mg/g of chlorophyll content was found in BA-132 which was lowest among all the accessions tested. The accession BA-132 recorded maximum amount of total phenol content 1.46 mg/g) in the healthy and 2.01 mg/g in the infested plants. This was followed by resistant accessions such as BA-155 and BA-147, which recorded the total phenol content of 1.37, 1.25 mg/g and 1.84, 1.64 mg/g in healthy and infected plants. With reference to OD phenol on selected rice accessions, the content varied from 0.09 to 0.31 mg/g and 0.11 to 0.50 mg/g in healthy and YSB infested plants. The utmost of OD phenol content was observed on healthy as well as infested plants on BA-132, BA-155 and BA-147 with 0.31, 0.25, 0.20 mg/g and 0.50, 0.40, 0.32 mg/g, respectively. The resultant increase in percentage of OD phenol content due to stem borer attack was as high as 61.29% in BA-132, followed by 60.00% on BA-155 and BA-147. Whereas, the lowest per cent OD phenol content was recorded in TN-1 (22.22%). Tannin content of the chosen rice accessions ranged from 0.58 to 1.34 mg/g on healthy and 0.70 to 2.22 mg/g on YSB infested plants. The infested resistant rice accessions (BA-132, BA-155 and BA-147) enlisted 2.22, 1.82 and 1.74 mg/g of tannin content.