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Background: Grain amaranth (Amaranthus spp.) has been cultivated since ancient times in some countries in the world and it is one of the oldest food crops. At present, the crop has gained more importance in the plains of India, especially in parts of Gujarat and Maharashtra. Grain amaranth exhibits an incredible extent of morphological diversity and an extensive adaptability to diverse eco-geographical conditions. Hence, the aim of the recent research was to evaluate the genetic diversity of 19 genotypes from four diverse species of Amaranthus from India using ISSR markers. Results: The set of 11 polymorphic ISSR primers produced a total of 114 amplicons, among which 98 amplicons were polymorphic. The mean number of polymorphic amplicons per primer was 8.91. Overall, the size of PCR-amplified DNA fragments ranged from 200 to 3702 bp. The average percent polymorphism was 87.15%, and the average PIC value was 0.853, which indicates good selection of primers in the present study for the assessment of genetic diversity. The unique amplicon (marker)-producing primers were also found which can be used for identification of genotypes. The dendrogram grouped 19 grain amaranth genotypes into two major clusters. The groups formed on the principle component analysis (PCA) plot resembles with the results of the dendrogram although some genotypes have been diverted on the PCA plot. Conclusions: The technique may be used to obtain reasonably precise information on the genetic relationship among grain amaranth genotypes. Such information may be useful for selecting the diverse parents and monitoring the genetic diversity periodically in the breeder's working collection of grain amaranth.

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Present investigation was undertaken to evaluate 50 linseed genotypes for three consecutive years for seed yield, oil content and agro-morphological traits using multivariate approach. Higher range, large value of Shannon-weaver diversity index for both traits and genotypes and large differences in mean values for most of the characters showed that a wide and significant variation existed among the genotypes and traits. Pooled analysis of variance revealed highly significant differences (p<0.001) among the genotypes for all the characters studied. The magnitude of the phenotypic coefficient of variation was somewhat higher than the genotypic coefficient of variation, indicating that the environment had little impact on the expression of these traits. Cluster analysis for yield and agro-morphological traits using unweighted pair group method of arithmetic averages (UPGMA) grouped the genotypes into nine clusters with varied number. Clustering of linseed genotypes from different geographical locations or source/origin into same cluster has confirmed that they are genetically related, and possibly from the same progenitor. The principal component analysis (PCA) revealed that most of the variation (76.41%) was accounted by first four PCA and indicated role of traits that contributed significantly towards a wide variation among the genotypes. The positive associations of seed yield per plant and oil content with component trait implies that improving one or more component traits could result in genetic enhancement of seed yield and oil content in linseed. The significant negative association of seed yield per plant and oil content with days to flowering and days to maturity has great advantages in breeding short duration linseed cultivars for hot and water stress climatic conditions of semi-arid regions. Trait specific genotypes namely, Shival, Sharda, IC54970, Mukta, IC56363, T-397, IC53281 and RLC-92 were identified for the development of short duration and dwarf cultivars with higher omega-3-fatty acid content.