Env Exp Biol (2013) 11: 39–46

Salt tolerance of Indian mustard (Brassica juncea) at germination and early seedling growth

Abstract

Soil salinity is one of the most important constraints limiting crop production in arid and semi arid regions. Seed germination is a critical stage in the life history of individual plants and salt tolerance during germination is crucial for the establishment of plants growing in saline soils. The research was carried out in order to test the effect of salinity on germination traits and seedling growth in 25 Indian mustard (Brassica juncea) genotypes. The results revealed statistically significant effects of salinity (EC 12 dS m^–1) on germination traits as well as growth characteristics of seedlings. Genotypic responses were significant for germination percentage, speed of germination, germination index, and relative germination rate, which were all generally retarded by salt stress. However, the mean germination time increased under saline conditions. Decline in root/shoot ratio and dry matter of seedlings was observed under salinity. Six mustard genotypes were characterized by significantly higher tolerance index for root growth. Significant correlation existed between tolerance index and shoot length, dry matter and also salt tolerance efficiency. Based on the results, the genotypes RB-10 and PR-2004-2 were identified as highly tolerant and NDR-05-01, PBR300, RK-05-01, NPJ-93, PDR-1188 and RGN-145 as moderately tolerant to salt stress.