Screening Groundnut (Arachis hypogaea L.) Germplasm for Salinity Tolerance

Abstract

Salinity is an increasing concern for the productivity of staple food crop. Crops with improved salt tolerance are highly needed to cultivate saline lands. Groundnut demand is increasing in countries like India, where saline land could be put under groundnut cultivation. The objective of this study was to identify groundnut genotypes with salinity tolerance for breeding programs. A set of 275 groundnut germplasm accessions were screened across three different seasons for salinity tolerance. Shoot biomass and seed yield under saline and non-saline conditions were recorded. Shoot biomass under saline conditions showed limited genotypic variation and was not determined as a selection criterion in the subsequent trials. While a six-fold range of variation for pod yield under salinity (10-12.5 dSm^-1 NaCl) was observed. Pod weight under saline and control conditions had week correlation. Although there was a considerable genotypic variation of pod yield under saline conditions, the G×E interaction was observable as well. We report a set of 14 tolerant and 17 sensitive groundnut genotypes based on pod-seed yield and pod-seed numbers under saline conditions in the seasons studied. Among all the genotypes, ICGV 87187 and ICGS 76 were the most tolerant lines and ICG 6993 and ICG 4746 were the most susceptible lines in 2006 and 2006-2007, respectively. The suggested lines could be used in further breeding programs such as populations mapping. Our assumption to identify salt tolerant groundnut lines from selected landraces of putative saline areas did not help successfully to get more promising lines nevertheless the mini-core set of germplasm provided most of the salinity tolerant entries.