RESUMO
Lentil (Lens culinaris Medik.) is one of the major cool-season pulse crops worldwide. Its increasing demand as a staple pulse has led to the unlocking of diverse germplasm collections conserved in the genebanks to develop its superior varieties. The Indian National Genebank, housed at the Indian Council of Agricultural Research (ICAR)-National Bureau of Plant Genetic Resources, New Delhi, India, currently has 2,324 accessions comprising 1,796 indigenous and 528 exotic collections. This study was conducted to unveil the potential of lentil germplasm by assessing its agro-morphological characteristics and diversity, identifying trait-specific germplasm, and developing a core set. The complete germplasm set was characterized for two years, i.e., 2017-2018 and 2018-2019, and data were recorded on 26 agro-morphological traits. High phenotypic variability was observed for nine quantitative and 17 qualitative traits. A core set comprising 170 accessions (137 Indian and 33 exotic) was derived based on the characterization data as well as geographical origin using a heuristic method and PowerCore software. This core set was found to be sufficiently diverse and representative of the entire collection based on the comparison made using Shannon-Weaver diversity indices and χ2 test. These results were further validated by summary statistics. The core set displayed high genetic diversity as evident from a higher coefficient of variance in comparison to the entire set for individual traits and overall Shannon-Weaver diversity indices (entire: 1.054; core: 1.361). In addition, the total variation explained by the first three principal components was higher in the core set (70.69%) than in the entire collection (68.03%). Further, the conservation of pairwise correlation values among descriptors in the entire and core set reflected the maintenance of the structure of the whole set. Based on the results, this core set is believed to represent the entire collection, completely. Therefore, it constitutes a potential set of germplasm that can be used in the genetic enhancement of lentils.
RESUMO
The synthetic characters of different plant communities are analysed. Community-coefficient for tree and shrub layer were 89.99 and 88.49; respectively in North-West aspect of Cedrus deodara forest; probably due to maximum number of species common to both sites. Among the twelve tree species; only two viz.; Cedrus deodara and Cupressus torulosa showed 100 presence amongst all the sites. The maximum equitability (10.47) value was computed in site five; because of similar type of species found in this site. Cedrus deodara (6.34) and Cupressus torulosa (5.54) had broader niches due to their presence at all the sites. Species diversity was highest (3.22) on the North West (NW) aspect of the V site and was directly related to the high density of tree species in this site. Dominance-diversity curve (d-d curve) for the tree layer and shrub layer; based on Importance Value Index (IVI) exhibited a geometric series for all forest sites except site IV; where it reflected Preston's log normal models. The log normal distribution of this site indicated the mixed nature of vegetation. These species are gradually loosing their niche width; density; dominance and diversity in different sites because of over exploitation and over grazing pressure on these species. In view of the great anthropogenic pressure on the plant community; conservation and management measures are required for sustainable use of these important ethnobotanical plant species and plant biodiversity protection
