Drought tolerance indices for selection of drought tolerant, high yielding upland rice genotypes

Abstract

The purposes of this study were (1) to assess the effectiveness of drought tolerance indices for selection of drought tolerance in upland rice, and (2) to identify the most suitable drought tolerance indices to select for drought tolerant, high yielding upland rice genotypes. This study employed a Split Plot design consisting of irrigation levels as the main plots, and rice genotype as the sub-plot treatments. There were three main plots: 100% field capacity (FC); 75% FC; and 50% FC level. The subplot treatments consisted of 40 upland rice genotypes. Grain yields under no-stress and stressed conditions were used to calculate drought tolerance indices. There were significant variations in grain yields and drought tolerance indices between different rice genotype treatments. The indices from the literature found to be most suitable for the selection of drought tolerant upland rice cultivars were STI, GMP, MRP, HARM, REI, ATI, YI, SNPI. Ten genotypes from among the 40 tested - namely HK-07, ADN-04, PMK-01, ADN-05, NGR-022, ALR-02, HK-06, and KMD-01 - were selected as combining drought tolerance with high yield potential.