Salinity is one of the major factors reducing plant growth and productivity worldwide and affects about 7% of world's total land area. In India about 6.73 million hectare of land area is salt affected. Wheat is the second most important crop after rice in India and occupies approximately 28.5 million hectare area. Several tolerance indices comprising of mean productivity (MP), geometric mean productivity (GMP), stress tolerance index (STI), stress stability index (SSI), tolerance index (TOL), yield index (YI) and yield stability index (YSI) were calculated in this investigation for salinity and its ability to understand which one or more predictor among studied indices based on correlation, principal component analysis and cluster analysis. Ten wheat genotypes were evaluated in two successive growing seasons (2012)(2013)(2014), with complete randomized design with three replications under both salinity stress and non-salinity to identify salt tolerant genotypes to the target environment. Multiple indices for salt tolerance were calculated based on the potential yield (Yp) under non-stress and yield (Ys) under stress conditions. The Ys and Yp showed highest significant and positive correlations with GMP, MP and STI among indices studied. Therefore, these indices were considered as a better predictor of Ys and Yp than TOL, SSI and YSI. Principal component analysis classified the genotypes into two groups. The first two PCs with eigen values >1 contributed 99.74% of the variability amongst genotypes. PC1 accounted for about 5.24% of the variation in salt tolerance indices and PC2 for 3.74%. The first PC was related to Ys, Yp, MP, GMP, STI and YI whereas the second PC related to Yp, TOL and SSI. The cluster analysis sequestrated ten genotypes into two clusters based on Ward's method. According to results, salinity significantly reduced the yield of some genotypes while some were found tolerant to stress indicating sufficient genetic variability for salinity tolerance among the studied genotypes. It could be implicated in selection of salinity tolerant wheat genotypes for the development of bread wheat varieties.

In the present study, 14 sugarcane (Saccharum spp. hybrid) genotypes were used for genomic diversity analysis based on nineteen inter simple sequence repeat (ISSR). These nineteen sets of ISSR markers generated a total of 164 discernible and reproducible bands including 109 polymorphic and 55 monomorphic bands. The unweighted pair group method with arithmetic average (UPGMA) analysis revealed three distinct clusters: I, II and III within the 14 genotypes. The polymorphic information content (PIC) value per locus ranged from 0.14 (UBC811) to 0.53 (ISSR1) locus with an average of 0.42 for all loci. The range of genetic distance or coefficient of similarity among sugarcane genotypes varied 0.14 - 0.78. The analysis of these similarities matrix revealed that greater similarity between CoS03234 and CoSe1424 (0.78), and lowest similarity between CoS03234 and Co0118 (0.14). The knowledge gained in this study would be useful to future breeding programs for increasing genetic diversity of sugarcane varieties and cultivars to meet the increasing demand of sugarcane cultivation for sugar and bio energy uses.

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The present study aimed to evaluate the genetic diversity of 10 wheat cultivars by Random Amplified Pol-ymorphic DNA (RAPD) marker. The genomic DNA of 10 wheat genotypes were amplified with 10 RAPD primers that produced 53 amplified band, out of which 23 band were polymorphic (43.39%). The number of fragment amplified per primer ranged from 4 to 9. Primer A01 generated maximum number of amplified band, out of which 5 band were polymorphic. Cluster analysis of wheat genotypes were based on UPGMA method. Cluster analysis of 10 wheat genotypes were classified in to two main group; single variety AKW 1071 was placed in first group and rest 9 variety were placed in second group. The pair wise similarity values ranged from 0.58% to 100% and showed that cultivars Raj-3765 and K-7903 were the closest with highest similarity value (100%), while genotypes AKW 1071 and K9006 showed minimum similarity value (62%). The present study indicated the presence of high genetic diversity among wheat cultivars, which could be used for the developing core collection of wheat germplasm for breeding purpose.