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Grass pea (Lathyrus sativus L.) is an important food crop cultivated in dryland agricultural ecosystem. It is an important source of dietary protein to millions of people living in low-income countries in South-east Asia and Africa. The present study emphasises the development of genomic resources and their application in marker–trait association for plant phenology and yield-related traits in lathyrus. In silico mining of nucleotide sequences identified 203 simple sequence repeat (SSR) motifs, of which trimer repeats (62%) were most abundant followed by tetramer (19%), hexamer (10%), pentamer (6%) and dimer (3%) nucleotide repeats. Of 150 SSR markers screened, 60 markers were amplified 75 alleles from 50 germplasm lines with 2–3 alleles per locus and the polymorphic information content of 0.45 was observed. We report 6 significant marker–trait associations using the developed SSR markers for plant phenology and yield-related traits following mixed linear model (Q+K) analysis. Gene ontology search of trait linked markers revealed marker regions encoding genes related to homeobox-leucine zipper protein ATHB-6-like, rubredoxin family protein, and cationic peroxidise. Understanding the association of novel alleles in trait expression will play a significant role in future lathyrus crop improvement programmes. Many cultivated crops are experiencing threats to the changing climatic conditions in recent years. Therefore, identifying genotypes resilient to various climatic conditions and mining of novel genes/alleles related to biotic and abiotic stress tolerance in underutilised crops such as lathyrus will help to breed better varieties in coming years through markers assisted breeding and genomic selection. Here, we report significant marker–trait associations for plant phenology and yield-related traits in grass pea using SSR markers. [ABSTRACT FROM AUTHOR]

In the present study, a diverse panel of 96 accessions of lentil germplasm was used to study flowering time over environments and to identify simple sequence repeat markers associated with flowering time through association mapping. The study showed high broad sense heritability estimate (h2bs=0.93) for flowering time in lentil. Screening of 534 SSR markers resulted in an identification of 75 SSR polymorphic markers (13.9%) across studied genotypes. These markers amplified 266 loci and generated 697 alleles ranging from two to 16 alleles per locus. Model-based cluster analysis used for the determination of population structure resulted in the identification of two distinct subpopulations. Distribution of flowering time was ranged from 40 to 70 days in subpopulation I and from 54 to 69 days in subpopulation II and did not skew either late or early flowering time within a subpopulation. No admixture was observed within the subpopulations. Use of the most accepted maximum likelihood model (P3D mixed linear model with optimum compression) of MTA analysis showed significant association of 26 SSR markers with flowering time at <0.05 probability. The percent of phenotypic explained by each associated marker with flowering time ranged from 2.1 to 21.8% and identified QTLs for flowering time explaining high phenotypic variation across the environments (10.7-21.8%) or in a particular environment (10.2-21.4%). In the present study, 13 EST-SSR showed significant association with flowering time and explained large phenotypic variation (2.3-21.8%) compared to genomic SSR markers (2.1-10.2%). Hence, these markers can be used as functional markers in the lentil breeding program to develop short duration cultivars. [ABSTRACT FROM AUTHOR]

Understanding genetic diversity and population structure is prerequisite to broaden the cultivated base of any crop. In the current investigation, we report discovery of a total of 319 alleles by assaying 81 SSRs on 71 chickpea genotypes. The cluster analysis based on Jaccard coefficient and unweighted neighbor joining algorithm categorized all genotypes into two major clusters. Cultivars grown within the same agro-climatic zones were clustered together, whereas the remaining genotypes particularly advanced breeding lines and accessions assigned to another cluster. Population structure analysis separated the entire collection into two subpopulations ( K = 2) and the clustering pattern remained in close agreement with those of distance-based methods. Importantly, we also discovered marker trait association for membrane stability index (MSI) and leaf chlorophyll content measured as SPAD chlorophyll meter reading (SCMR), the two important physiological parameters indicative of heat stress (HS) tolerance in chickpea. Association analysis using both general linear and mixed linear models of the mean phenotypic data of traits recorded in 2016 and 2017 uncovered significant association of NCPGR206 and H2L102 with the MSI trait. Likewise, SSR markers GA9, TR31 and TA113 exhibited significant association with SCMR trait. The genomic regions putatively linked with two traits may be investigated in greater detail to further improve knowledge about the genetic architecture of HS tolerance in chickpea. [ABSTRACT FROM AUTHOR]

Grass pea ( Lathyrus sativus) is an important food-legume crop for resource-poor farmers in the developing world. However, given its cultivation in the most underprivileged regions, the crop has not received appropriate scientific attention particularly from the genomic perspective, thereby giving it a status of genomic orphan. Nevertheless, some recent studies have attempted to develop modern molecular tools to strengthen the genetic and genomic research. In the present investigation, a comprehensive collection comprising 176 accessions was analysed using EST-simple sequence repeats ( SSRs). The SSR analysis revealed existence of a total of 51 alleles with an average polymorphic information content value of 0.35. A moderate level of gene diversity was noticed that ranged from 0.04 to 0.73 with an average of 0.43. Noticeably, two distinct subpopulations were recovered using cluster analysis. In addition, the presence of admixtures in population reflected the strong possibilities of gene flow between the accessions across the geographical boundary. In summary, we provide additional insights about the informativeness of available EST- SSR markers along with an extended understanding of relatedness, genetic structure and gene flow in an under-researched legume crop. [ABSTRACT FROM AUTHOR]