Morphometric characterization of Jatropha curcas germplasm of North-East India

The morphological variation among Jatropha curcas L. populations from 29 different locations of North-East India was determined. Four populations from other parts of India were also incorporated in the study as an out-group. The morphological trait based analysis of J. curcas revealed large variation of quantitative traits among the populations. Of the six morphological traits used in this study, the highest variation (% coefficient of variation=23.19) was observed in floral sex ratio (M: F) while canopy spread (CS) appeared as the least variable trait (% coefficient of variation=1.67). Based on morphometric trait values, the three populations from Assam (IITJC15, IITJC24 and IITJC28) and one population from Arunachal Pradesh (IITJC7) emerged as superior when compared with the other populations. Both cluster and principal component analyses depicted that the populations IITJC19, IITJC21, IITJC22 and IITJC24 from Assam maintained maximum inter-cluster distance from the rest of the populations and are, thus, substantially distinct. The analyses also depicted that no clear demarcation can be made between populations from North-Eastern India and other areas on the basis of morphometric variability alone. Morphometric characterization of J. curcas populations leads to the identification of seven promising populations (IITJC7, IITJC15, IITJC19, IITJC21, IITJC22, IITJC24 and IITJC28) from North-East India which can substantially contribute to Jatropha breeding in the future. From the study of variance components and broad sense heritability, it was suggested that the selection of elite plants on the basis of M: F ratio, 100 seed weight (100SW) and total seed yield (TSY) in tree improvement programs is likely to be more successful.   Key words: Agronomic traits, cluster analysis, principal component analysis, heritability, ANOVA.