Biochemical Evaluation of Wheat Genotypes for Stress Tolerance

摘要

Cross bred wheat genotypes viz. RSP-561, RSP-566, RSP-529, RSP-564, RSP-511 and RSP-560 were evaluated biochemically on the basis of inherent stress tolerance characters viz. proline, reducing sugar, free amino acid, relative water content, total polyphenol, polyphenol oxidase, catalase and superoxide dismutase levels from the leaves at their flowering stages. National check wheat varieties PBW-175 and PBW-343 for abiotic and biotic stress tolerant /resistant respectively, were taken as references. It was observed that the wheat genotypes RSP-564, RSP-529 and PBW-175 possessed significantly high proline, free amino acid, reducing sugar and relative water content (RWC) with highest value in RSP-564. Similarly, biotic stress specific parameters viz. total polyphenol and polyphenol oxidase (PPO) levels were found maximum in RSP-564, whereas catalase and SOD activities, which plays vital roles in defense against both in biotic and abiotic stresses, were maximum in national cultivars PBW-343 and PBW-175. Wheat genotypes RSP-529 and RSP-564 also carried significantly high catalase and SOD activities with superiority to RSP-529. RSP-511 and RSP-561 genotypes showed moderate potentials while other wheat genotypes were found comparatively lower in these biochemical parameters. PBW-175 showed superiority in terms of proline, free amino acid, reducing sugar levels and relative water content over PBW-343 whereas higher content of total polyphenol content, PPO and catalase levels in PBW 343, justified the characters of PBW-175 and PBW-343 cultivars as biotic and abiotic stress tolerant, respectively. On the basis of biochemical evaluation for different parameters, wheat genotypes RSP-529 and RSP-564 are considered to possess comparatively good inherent tolerance properties against both biotic and abiotic stresses, as their values on concerned parameters are comparable to both abiotic stress resistant PBW-175 and biotic stress resistant PBW-343, and hence they can be considered as most potential genotypes against both environmental stresses and diseases/pests attacks.