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Fifty-two genotypes of Eleusine coracana collected from Uttarakhand hills were subjected to simple sequence repeat (SSR), random amplified polymorphic DNA (RAPD)-PCR and protein profiling analysis to investigate the variation in protein content. The main objective of the present study was to detect variability among E. coracana and also assess the discriminating ability of these three molecular methods. A total of 21 RAPD and 24 SSR primers were assayed for their specificity in detecting genetic variability in E. coracana, of which 20 RAPD and 21 SSR primers were highly reproducible and were found suitable for use in PCR analysis. Assessing genetic diversity among E. coracana genotypes by RAPD-PCR using 20 polymorphic primers yielded 56 different RAPD markers which clustered the genotypes into different groups on the basis of protein content. Similarly, SSR-PCR with 21 polymorphic primers clustered the genotypes into different groups. On the other hand, biochemical typing of E. coracana using whole seed proteins generated profiles that showed no major difference indicating the technique to be not useful in typing genotypes of this crop. However, a few of the genotypes showed the presence of a unique band of 32 kDa that needs to be further investigated to understand the role of the protein from nutritional point of view, if any. In the present study, significant negative correlation ( r = −0.69*) was found between the protein and calcium content of finger millet genotypes. Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis based seed storage proteins generated profiles showed no major differences in banding pattern among 52 finger millet genotypes while quantitative estimation of seed storage protein fractions using Lowry method revealed that glutelin was highest followed by prolamin, globulin and albumin. [ABSTRACT FROM AUTHOR]

Magnaporthe grisea, the blast fungus is one of the main pathological threats to finger millet crop worldwide. A systematic search for the blast resistance gene analogs was carried out, using functional molecular markers. Three-fourths of the recognition-dependent disease resistance genes ( R-genes) identified in plants encodes nucleotide binding site (NBS) leucine-rich repeat (LRR) proteins. NBS-LRR homologs have only been isolated on a limited scale from Eleusine coracana. Genomic DNA sequences sharing homology with NBS region of resistance gene analogs were isolated and characterized from resistant genotypes of finger millet using PCR based approach with primers designed from conserved regions of NBS domain. Attempts were made to identify molecular markers linked to the resistance gene and to differentiate the resistant bulk from the susceptible bulk. A total of 9 NBS-LRR and 11 EST-SSR markers generated 75.6 and 73.5% polymorphism respectively amongst 73 finger millet genotypes. NBS-5, NBS-9, NBS-3 and EST-SSR-04 markers showed a clear polymorphism which differentiated resistant genotypes from susceptible genotypes. By comparing the banding pattern of different resistant and susceptible genotypes, five DNA amplifications of NBS and EST-SSR primers (NBS-05 NBS-09, NBS-07, NBS-03 and EST-SSR-04) were identified as markers for the blast resistance in resistant genotypes. Principal coordinate plot and UPGMA analysis formed similar groups of the genotypes and placed most of the resistant genotypes together showing a high level of genetic relatedness and the susceptible genotypes were placed in different groups on the basis of differential disease score. Our results provided a clue for the cloning of finger millet blast resistance gene analogs which not only facilitate the process of plant breeding but also molecular characterization of blast resistance gene analogs from Eleusine coracana. [ABSTRACT FROM AUTHOR]

Finger millet ( Eleusine coracana L.) is an important crop used for food, forage, and industrial products. Three DNA marker techniques, random amplified polymorphic DNA (RAPD), simple sequence repeat (SSR) and cytochrome P gene based markers were used for the detection of genetic polymorphism in 83 accessions of finger millet collected from various geographical regions of India and Africa. A total of 18 RAPD, 10 SSR and 10 pairs of cytochrome P gene based markers were generated 56.17, 70.19 and 54.29% polymorphism, respectively. Mean polymorphism information content (PIC) for each of these marker systems (0.280 for RAPD, 0.89 for SSR and 0.327 for cytochrome P gene based markers) suggested that SSR marker were highly effective in determining polymorphism. The phenograms based on the three markers data indicate that genotypes from different geographical regions are clearly distinguishable as separate clusters. Mantel test employed for detection of goodness of fit established cophenetic correlation values above 0.90 for all the three marker systems. The dendrograms and PCA plots derived from the binary data matrices of the three marker systems are highly concordant. High bootstrap values were obtained at major nodes of phenograms through WINBOOT software. Based on the results of present study, SSR and cytochrome P gene based markers appear to be particularly useful for the estimation of genetic diversity. This study reveals the potential of RAPD, SSR and gene based markers for characterizing germplasm of Eleusine coracana and narrow down the vast germplasm into distinct core groups. [ABSTRACT FROM AUTHOR]