Assessment of Genetic Diversity among Finger Millet (<Emphasis Type="Italic">Eleusine coracana</Emphasis> (L.) Gaertn.) Accessions using Molecular Markers

Finger millet (Eleusine coracana), an allotetraploid cereal, is widely cultivated in the arid and semiarid regions of the world. Being rich in protein and calcium, finger millet serves as an important staple food for rural populations in developing tropical countries where calcium deficiency and anemia are wide spread. Thirty-two finger millet genotypes were fingerprinted using 50 random amplified polymorphic DNA (RAPD) markers. Out of the total 529 loci generated using the 50 RAPD primers, 479 loci (91%) were polymorphic and informative to differentiate the accessions. Cluster analysis grouped the 32 finger millet accessions into two major clusters. Among the 32 finger millet genotypes, GEC 182 and CO 12 were distantly related with a low similarity index of 0.315. These two accessions also differed considerably in days to flowering and grain weight; GEC 182 is early flowering and has bold grains, while CO 12 is late flowering and has smaller grains. These two accessions with higher diversity at molecular level, phenology and grain weight will be ideal as parents in hybridization programme, to develop improved finger millet varieties suitable for peninsular region of India.     

Genetic relationships of boxwood (<Emphasis Type="Italic">Buxus</Emphasis> L.) accessions based on genic simple sequence repeat markers

Boxwoods (Buxus L., Buxaceae) are popular woody landscape shrubs grown for their diverse forms and broad-leaved evergreen foliage. We used genic simple sequence repeat (genic-SSR) markers to assess genetic diversity and relatedness of 275 accessions from the National Boxwood Collection at the U.S. National Arboretum. Flow cytometry was conducted to determine the relative ploidy of each accession. Genic-SSR loci were highly variable among the accessions, detecting an average of 6.7 alleles per locus based on 17 primer pairs. Data were analyzed with a distance matrix based on Jaccard’s similarity index, followed by Unweighted Pair Group Method with Arithmetic Mean clustering. Two major clusters were identified, with four subclusters consisting of individual accessions from B. balearica Lam., B. bodinieri Lévl., B. harlandii Hance, B. microphylla Siebold et Zuccarini, B. sempervirens L., B. sinica (Rehd. et Wils.) M. Cheng, and their putative interspecific hybrids. The accessions generally clustered by cultivar, provenance, or species. Clustering within each group typically reflected breeding pedigrees, when known, and the clusters were supported by bootstrap results. This information will be used for breeding programs and collection management, and for identifying possible sources of disease tolerance for boxwood blight and other diseases and pests.