Comparative studies on stability parameters and index for selecting stable genotypes in upland (Gossypium hirsutum L.)

Abstract

Comparative studies on stability parameters and sustainability index for selecting stable genotypes in upland cotton (Gossypium hirsutum L.) was carried out accordinag to Eberhart and Russell model with sustainability index model. Stability analysis was carried out on 12 intra-hirsutum hybrids for seed cotton yield, number of bolls/plant, boll weight, 2.5 % span length, and bundle strength on three years data viz., 2001, 2002 and 2003. Based on the linear component (bi), non linear response (S2di) and high mean performance (x), CSHH 198, CSHH 238, CSHH 825 and Om Shankar were found stable for seed cotton yield. While based on sustainability index and best performance, the hybrids CSHH 238, CSHH 243, CSHH 4311 and CSHH 825 were found to be stable. Similarly, for number of bolls/plant deviation from regression was non significant for CSHH 198, CSHH 243, CSHH 825 and Ankur 651 whereas, on the basis of sustainability index and mean performance Om Shankar, CSHH 198, Ankur 651 and LHH 144 were found stable. For boll weight, all the hybrids recorded very high sustainability index, which indicated that this character is least influenced by the environmental factors, whereas, analysis of variance in the Eberhart and Russell model indicated absence of G x E interaction and hence no stability parameters can be estimated for boll weight. For quality traits like 2.5 % span length and tenacity had very high sustainability index in all the hybrids tested, indicating that these characters are least affected by environmental fluctuations. These results were found to be contrary with the findings based on Eberhart and Russell model and hence sustainability index model may not be used for selecting the stable genotypes.