Evaluation of Peanut Germplasm Tolerance to Salinity Stress

Abstract

Salt-tolerant variety is the main technology for developing peanut in saline soils. However, peanut breeding for salt-tolerant characteristic has not been done in Indonesia. The aim of this study was to evaluate 25 peanut germplasm accessions of Indonesian Legumes and Tuber Crops Research Institute collection for their tolerance to salinity stress to provide gene resource for the peanut breeding. The accessions were grown at three salinity levels i.e: non saline, moderate (5-6 dS/m) and high (8-10 dS/m). Observations consisted of toxicity score, K and Na content in root and shoot, pod and seed yield, and stress tolerance index (STI). The result showed that all accessions were identified as sensitive to high salinity, and salinity 5-6 dS/m seem to be the highest level that can be tolerated by the accessions tested. At moderate salinity, four accessions (MLGA 0211, MLGA 0222, MLGA 0546, MLGA 0570) identified tolerant, two accessions (MLGA 0473 and MLGA 0605) were sensitive, and the other 19 accessions were moderate. The tolerance to salinity related to the ability of the accessions to inhibit Na uptake as well as Na translocation to the shoot, and hence K/Na ratio in shoot keeps at high level. The ratio of Na-root/Na-shoot is as effective indicator as K/Na ratio in the shoot, therefore it can be new selection criteria of peanut tolerance to salinity stress. The salt-tolerant accessions can be employed and integrated in the peanut breeding for salinity tolerance and support the development of food crops in suboptimal lands.