FIELD RESISTANCE OF OKRA LINES AGAINST POD BORER (Erias spp) IN RABI SEASON

摘要

A study was undertaken to evaluate 171 diverse okra types (151 exotic and 20 indigenous) for relative susceptibilty to pod borer under field condition during rabi 1990. The trial was laid out in a randomised block design with three replications. A rowof three metres constituting 10 plants spaced at 60 x 30 cm in deep block vertisols in the Plantation Crop Unit, division of Horticulture, UAS, Dharwad was the individual treatment. No plant protection chemicals were sprayed in order to facilitate the build up of natural infestation. Five plants per treatment were randomly selected for recording the data on days to flowering, plant height, nodel length, pod length, total number of pods per plant, weight of good pods per plant, per cent infested pods per plant and per cent weight loss per plant. Number of healthy and infested pods as well as their respective weights were recorded for each picking and were summed up for the calculation of per cent infested pods and per cent yield loss, on per plant basis. The genotypes were grouped into three categories based on per cent infested pods per plant as (a) Resistant [ (> m + sigma) (00.00 to 26.82%)], (b) Moderately tolerant [ (m - sigma) to (m + a) (26.83 to 73.80) ] (c) Susceptible [ (> m + sigma) (74.00to 100) ], where, m = mean, a = standard deviation.