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Soybean is an excellent source of high quality protein and vegetable oil for human and animals. The diverse and increasing demands for soybean have created enough opportunities for breeders to improve the soybean seed composition traits influencing nutritional parameters. Protein and oil content, protein subunit composition, fatty acid composition, anti-nutritional factors etc. are some of the important seed traits that need to be improved to enhance the nutritional value of soybean as food and feed. Many studies have been carried out to modify the seed composition traits to enhance the nutritional quality of soybean. The extensive screening of worldwide soybean germplasm collections has led to the identification of many genotypes with significant variation for seed composition traits. In addition, induced mutagenesis has contributed immensely in improving the quality of soybean seeds by creating novel mutant genotypes for various seed quality traits. Gene/QTL mapping and molecular characterization of these mutants had led to elucidation of gene function and significantly increased the knowledge on molecular basis of seed composition traits. The emergence of modern biotechnological tools like siRNA and targeted mutagenesis techniques like CRISPR/Cas9 has further opened new opportunities in modifying the nutritional value of soybean. This review article provides comprehensive and up-to-date knowledge about the genetic improvement of important seed composition traits in soybean by conventional and biotechnological approaches. The article also discusses the major challenges and limitations in genetic enhancement and utilization of quality related traits in soybean. [ABSTRACT FROM AUTHOR]

Mungbean ( Vigna radiata (L.) Wilczek) is an important food legume, but has limited genomic resources. In this study, the development of genic SSR markers from mungbean transcriptome sequences and their transferability to related Vigna species is presented. A total of 12,596 EST sequences from mungbean genotype ‘Jangan’ were searched for the presence of SSRs and 2,299 SSR motifs from 1,848 SSR containing unique ESTs were identified with an average of one SSR per 3.4 kb. Trinucleotide motifs (48 %) were the most abundant repeats followed by di- (25 %), tetra- (15 %), hexa- (7 %) and penta- (5 %) nucleotide repeats. Based on these SSR containing sequences, PCR primer pairs were successfully designed for 1,742 SSR loci and randomly selected 100 primer pairs were further used for characterization. Sequences analyses indicate that about 45 % of the SSR motifs were present in the coding sequences (CDS) and 55 % were located in the untranslated regions (UTRs). Trinucleotide repeats (62 %) were preferentially present in the CDS. Randomly selected 27 SSR markers were used to study the genetic relationship among 20 mungbean genotypes. Twenty one (78 %) genic SSR markers showed polymorphism and the number of alleles ranged from two to six with an average PIC value of 0.34. Cluster analysis based on similarity coefficient clearly separated the cultivated and the wild genotypes into separate groups. Transferability study showed that 97 % SSR markers were transferable to eight other Vigna species, hereby expanding their utility. This study gives an insight into frequency, type and distribution of SSRs in the genic region of mungbean and report the development of a large set of SSR markers for mungbean. These genic SSR markers will provide an important genomic resource for qualitative and quantitative traits mapping, marker assisted selection and genetic diversity studies in mungbean and related Vigna species. [ABSTRACT FROM AUTHOR]

n inter-subspecific mapping population was generated by crossing V. mungo var. mungo (cv. TU 94-2, bruchid susceptible) and V. mungo var. silvestris (bruchid resistant). About 37.8% of the bruchid completed their lifecycle on seeds of V. mungo var. silvestris compared with 100% on the susceptible variety TU 94-2. The total developmental period of C. maculatus on Vigna mungo var. silvestris was considerably extended (88 days as compared with 34 days on TU 94-2). A genetic linkage map constructed using recombinant inbred lines (RILs) in F generation with 428 markers [86 random amplified polymorphic DNA (RAPD), 47 simple sequence repeat (SSR), 41 inter-SSR (ISSR), 254 amplified fragment length polymorphism (AFLP)] was used for QTL detection. One hundred four individuals were used for detection of QTLs associated with bruchid resistance. The RILs exhibited a high level of variation in percentage adult emergence (0-100%) and developmental period (0-105 days). Two QTLs, Cmrae1.1 and Cmrae1.2, were identified for percentage adult emergence, on linkage group (LG) 3 and 4, respectively. For developmental period, six QTLs were identified, with two QTLs ( Cmrdp1.1 and Cmrdp1.2) on LG 1, three QTLs ( Cmrdp1.3, Cmrdp1.4, and Cmrdp1.5) on LG 2, and one QTL ( Cmrdp1.6) on LG 10. [ABSTRACT FROM AUTHOR]

The recessive adult plant resistance (APR) gene Lr48 in wheat was tagged with flanking random amplified polymorphic DNA (RAPD) markers. Markers S336775 in coupling and S3450 in repulsion with Lr48 were identified in wheat line CSP44. Tests of these markers on available Thatcher near-isogenic lines (NILs) detected the likely presence of Lr48 in TcLr25. A test of allelism of APR involving the cross TcLr25 × CSP44 indicated that Lr48 was present in both lines. A separate experiment on inheritance of resistance in an F2 population of TcLr25 × Agra Local confirmed the presence of a dominant seedling resistance gene ( Lr25) and a recessive APR gene ( Lr48) in TcLr25. This study demonstrated the value of molecular markers in identifying the presence of masked genes in genetic stocks where direct phenotyping failed to detect their presence. [ABSTRACT FROM AUTHOR]