Abstract

Genetic association, divergence and variability were studied in 24 accessions of Jatropha curcas L. for seed and oil yield and its contributing traits. Based on genetic divergence D²statistics, 24 accessions were grouped into 14 clusters. Three accessions (BRS-12/05-UpA2, BRS-12/05-UpA3 and BRS-03/06-WbB) were included in cluster XI followed by clusters II, IV, VI, VII, VIII, X, XII and XIII (2 accessions in each case), whereas clusters I, III, V, IX, XIV included only 1 accession in each case. Intra and inter-cluster values ranged from 0.00 to 12.220 and 7.868 to 70.340, respectively and clusters XIV and VI were the most diverse, which could be used in hybridization programme. Phenotypic variances were higher than genotypic variances for all characters. Heritability coupled with genetic advance was higher for plant height (74.101%, 80.171), oil content (77.956%, 16.210) and fruit set (57.430%, 15.890). Substantial amount of genetic variability was noticed among the Jatropha accessions. Correlation and path coefficient analyses showed that seed yield/plant was significantly associated with fruit set whereas oil content was found to significantly correlate with plant height, stem diameter and number of branches/plant. Fruit set had the highest positive direct path followed by stem diameter towards seed yield/plant. Fruit set also indirectly contributed to seed yield/plant via plant height and stem diameter. Characters showing significant and positive correlation with seed yield and oil content can be used for genetic improvement of seed and oil yield which will ultimately enhance biodiesel productivity in J. curcas.

Key words: Divergence, interrelationship, Jatropha curcas, oil content, seed yield, variability.