Effect of drought on oil, fatty acids and protein contents of groundnut (Arachis hypogaea L) seeds

The rainfed groundnut (Arachis hypogaea L.) crop suffers from moisture stress of varying intensity at different growth stages. The effect of drought on oil, protein and fatty acid contents were studied in 12 genotypes that differed in seed quality traits. The genotypes were subjected to mid-season and the end-of-season drought in field experiments at ICRISAT Asia Center (IAC), Patancheru, India, conducted during the 1991/92 and 1992/93 postrainy (November-April) seasons. Mid-season drought was imposed between 40 and 80 days after sowing (DAS). The crop received normal irrigation, 50 mm at 10 day intervals, before and after the imposition of mid-season drought until harvest. Using the line-source sprinkler technique, end-of-season drought of varying intensity was imposed from 80 DAS until harvest. Mid-season drought had no significant effect on the content of oil, protein and fatty acids other than eicosenoic fatty acid. End-of-season drought significantly reduced total oil, and linoleic and behenic fatty acid content, and significantly increased total protein and stearic and oleic fatty acid content. However, genotype by treatment interactions were found. In ICGVs 88369, 88371, 88381, 88382 and 88403, total oil content remained unaffected while oleic fatty acid content increased under end-of-season drought. These were identified as desirable parents for a breeding program to develop cultivars suitable for rainfed cultivation.