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Onion is an economically important vegetable cultivated worldwide on a large scale. Liberal exchange of germplasm and frequent selection caused narrow genetic diversity in most crops, including onion. Thus, it is essential to estimate and understand genetic diversity before launching of any breeding program. The current study was conducted to explore genetic diversity among 39 short-day onion genotypes (indigenous and exotic).All the genotypes were evaluated for various phenotypic traits by using single nucleotide polymorphism (SNP) genotyping based on KASPar assays. Principal component analysis (PCA) was performed to determine the variability among genotypes. The four principal components with eigenvalue greater than 1 accounted for 67.5656% variability for quantitative traits, whereas first five principal components with eigenvalue greater than 0.7 accounted for 86.24% variation among the genotypes for qualitative traits. The principal component analysis identified diverse traits including bulb weight, bulb diameter, plant height, number of survived plants and vitamin C. These traits were further analyzed through ANOVA (Analysis of Variance) following augmented block design to describe genotypic variability for selected traits. Onion genotypes showed significant variation for bulb weight, bulb diameter and Vitamin C. Genotypic clustering based on PCA showed that 15 indigenous genotypes were clustered with exotic genotypes (14) while remaining indigenous genotypes (10) were distant. A total of 30 SNPs were used for assessment of genetic diversity out of these, 24 SNPs were detected with polymorphic loci (0.8%, heterozygosity), while only six markers were with monomorphic sites (0.2% heterozygosity). Subsequently, population structure analysis revealed three different populations indicating significant variability.Conclusively, a significant similarity between exotic and a group of indigenous genotypes indicates direct adoption of exotic genotypes or their sister lines. A further broadening of the genetic base is required and could be done by crossing distant genotypes.

Random amplified polymorphic DNA (RAPD) markers have been found to be very useful in studying the genetic variability of different species, including Rosa. Present studies were undertaken for the identification and analysis of genetic variation within a collection of 4 species and 30 accessions of rose using RAPD analysis technique. The results showed the molecular distinctions among the genotypes when analysed using 25 RAPD primers. Total amplified bands were 146, out of which 110 were polymorphic, with an average of seven bands per primer. Maximum number of bands (10) was produced by primer GLD-20, while GLC-02 produced the minimum number of bands (2). Maximum polymorphism in the present study was obtained by primer GLA-03, GLA-05, GLA-07, GLA-10, GLC-02, GLC-06, GLC-08, GLC-10, OPG-11 and OPE-19 which produced 100% polymorphic bands, while primer GLB-11 produced only 42.85% polymorphic bands. This study demonstrated the potential of RAPD technique for the characterization of genetic variation within the rose germplasm. Key words: Random amplified polymorphic DNA, polymorphism, rose germplasm, primer.

Narrowing genetic diversity is a limiting factor in wheat breeding. Popularity of semi dwarf cultivars, developed after green revolution, has resulted in genetic erosion as they replaced indigenous cultivars derived from landraces. These old cultivars have a wealth of useful genes that can be incorporated in the modern cultivars to improve their tolerance level against biotic and abiotic stresses. Genetic analysis of these indigenous and advanced cultivars by the SSR markers has shown greater diversity in this valuable Indian sub-continental germplasm and grouped them into seven units. The Triticum durum lines T2 and T3 were placed in group A, whereas their counterpart T1 was quite distinct. Of the selections, T4 to T9 that was clustered in Group B, T4 to T7 were of Triticum sphaerococcum , whereas the other two were of Triticum aestivum type. T. aestivum cultivar C-248 also appeared to be distinct and could not be grouped with any other cultivar. Based on genetic divergence, therefore, T1 can be used for enhancing diversity in T. durum and C-248 in T. aestivum . Keywords: Triticum , germplasm, simple sequence repeats, genetic diversity

Conservation and utilization of the native plant resources is essential for long term sustainability of biodiversity. Wild native resources are adapted to specific and diverse environmental conditions and therefore, these adaptive features can be introduced into modern cultivars either through conventional breeding or advanced molecular genetic techniques. Understanding the genetic make up of the wildly growing plant species and of target desirable genes is a prerequisite for this purpose. Five wild rose (Rosa L.) genotypes were collected from different locations in northern hilly areas of Pakistan for this study. Different morphological characteristics and PCR based random amplified polymorphic DNA (RAPD) technique was used to find out the diversity and relationship among the genotypes. On morphological basis, Rosa webbiana collected from Muree and Nathia gali showed maximum (83%) similarity, whereas on DNA pattern basis, Rosa brunonii collected from Bansra gali and Sunny bank showed maximum (72%) similarity, while R. webbiana showed maximum diversity among all the species.Key words: Genetic diversity, morphological differences, random amplified polymorphic DNA (RAPD), Rosa.

The Bcl-2-associated athanogene (BAG) proteins are involved in the regulation of Hsp70/HSC70 in animals. There are six BAG genes in human that encode nine isoforms with different subcellular locations. Arabidopsis thaliana is reported to contain seven BAG proteins. We searched BAG proteins in Oryza sativa using profile-sequence (Pfam) and profile-profile (FFAS) algorithms and found six homologs. The BAG protein family in O. sativa can be grouped into two classes based on the presence of other conserved domains. Class I consists of four OsBAG genes (1 to 4) containing an additional ubiquitin-like domain, structurally similar to the human BAG1 proteins and might be BAG1 orthologs in plants. Class II consists of two OsBAG genes (5 and 6) containing calmodulin-binding domain. Multiple sequence alignment and structural models of O. sativa BAG proteins showed conservation of surface charge (except OsBAG5) and critical residues for the binding of BAG domain to Hsp70 nucleotide binding domain (NB). Meta analysis of microarray data showed that OsBAG genes are up or down regulated under different stresses (biotic and abiotic). Data obtained from real-time PCR of OsBAG genes under heat stress showed that maximum induction in the expression of all the genes occurred after one hour exposure to heat stress, while reduction in the expression was observed in the following time course and ultimately returned to the basal level at 24 h treatment. These results suggest that OsBAG genes might play important role at the onset of heat stress. A further detailed study may explore the exact function of the members of this gene family and help to make understanding of programmed cell death (PCD) mechanism in plants. Key words : Rice, ubiquitin-like domain, nucleotide-binding domain, real-time PCR.