Screening and selection of groundnut genotypes for tolerance of soil salinity

Field screening of 127 groundnut (Arachis hypogaea L.) genotypes was undertaken for two consecutive seasons at the experimental farm of Fruit Research Station, Mangrol, Junagadh, Gujarat, India to identify salinity tolerant genotypes based on plant mortality and seed yield. The plant mortality increased with the advancement of crop stages and a clearcut demarcation between salinity tolerant and sensitive genotypes was noticed at 90 days onwards. During summer season, the salinity level above 4 dS m-1 caused very high mortality of 50-100 % (average 91 %) with 100 % mortality in 54 sensitive genotypes, however, 29 genotypes survived with more than 5 % plant without any seed formation till maturity. But at the salinity level 3-4 dS m-1, during kharif season, the plant mortality was 0-88 % (average 30 %) and a number of genotypes produced seed, was ideal for screening. There was a large genotypic variation in pod yield and related traits with 0-13 pods plant-1 and 0-136 g m-2 seed yield and only 59 genotypes showed pod and seed bearing of which 20 genotypes had less than 10 % mortality. Overall the seed yield in a unit area (g m-2) was the best criterion for selecting the salinity tolerant genotypes. Based on two seasons data, 11 genotypes NRCG 2588, 4659, 5513, 6131, 6450, 6820, 6919, 7206, TMV 2 NLM, TG 33, JNDS-2004-15 with high plant stand and more than 50 g m-2 seed yield were identified as salinity tolerant. 10 genotypes JNDS-2004-1, JNDS-2004-3, JNDS-2004-16, TG 28, TG 38C, TG 42, PBS 30031, PBS 30033, NRCG 6155, ICGV 86031 with more than 35 g m-2 seed yield were identified as moderately tolerant for their use in an area having salinity up to 3 dS m-1.