Variation in Growth Performance of Acacia nilotica Willd. ex Del. Provenances of Wide Geographical Origin : Six Year Results

Results of a provenance trial of Acacia nilotica Willd. ex Del. laid out in 1993 at Tropical Forest Research Institute Campus, Jabalpur (23°N lat., 79°E long. and 400 m altitude) Madhya Pradesh, a semi-arid region of India are reported and discussed. Nineteen provenances from India, Pakistan, Sudan, Senegal and Yemen were evaluated in the field at age three and six years. Local source of A. nilotica (S.F.R.I., Jabalpur) was used as check material for comparison. Significant differences between the provenances (P < 0.05) were observed for height, diameter at breast height (DBH), number of branches and field survival. The provenances from Gujrat (Punjab), Pakistan, ranked first for growth traits namely height, DBH and survival. The next superior provenance was from Beihan, Yemen, which scored second highest values of height and DBH and had good survival at age six years. Results indicate that genetic differences exist between the provenances of A.nilotica. None of the traits assessed (viz. height, DBH, number of branches, inter-nodal length and survival) were found to correlate with any of the geographical coordinates of the provenances (latitude, longitude and altitude). Height, DBH and number of branches showed significant and positive correlation with each other. Fair differences between phenotypic and genotypic coefficient of variability were observed. Heritability values were found fairly good for height, DBH and number of branches as compared to inter-nodal length. The relative performance of these provenances was fairly consistent throughout the period of observation at three and six year. The two sources viz. Gujrat (Punjab), Pakistan and Beihan, Yemen, are recommended for plantation programme under semi-arid conditions.