The paper analyzed genetic parameters of 144 progenies of selected clones of Populus deltoides Bartr. ex. Marsh growing at the farm of WIMCO Seedligs Ltd., Bagwala, Rudapur (Uttarakhand), India, on the basis of growth traits viz. diameter at breast height (DBH) and height and wood traits namely fiber dimensions, vessel dimensions, proportion of tissues of secondry xylem, specific gravity. Progenies showed significant variations for all growth and wood traits. Broadsense heritability for wood traits ranged from 0.84 (fibril angle)-0.04 [vessel (%)] while for growth traits it was 0.88 (DBH) and 0.02 (height). Fiber length, fiber diameter, wall thickness, fiber (%), fibril angle and specific gravity were important wood traits showed 0.60, 0.72, 0.29, 0.40, 0.84 and 0.68 broadsense heritability respectively. The genetic advance was higher for vessel length (81.49) followed by fiber length (74.72), vessel diameter (10.16), fibril angle (9.81) and fiber (6.07 %). Genetic gain was higher for parenchyma (51.70 %) followed by fibril angle (31.42), fiber (17.70 %), ray (15.89 %), vessel length (15.44), wall thickness (13.65), specific gravity (11.84) and fiber length (6.48) for the wood traits. Genetic advance was 6.71 and 0.58 respectively for DBH and height for growth traits while genetic gain for DBH and height was 28.16 and 2.23. Cluster analysis indicated that 139 progenies were clustered in three clusters showing narrow genetic base of the species. However, the progenies B-13, seedling-S and 86-1 were divergent and also showed better wood and growth traits adjudged the best progenies for further development of new clones and hybrids. Moreover, 32 progenies were also showed better wood and growth traits and may also be used in tree improvement programs of the species. The hybridization among the progenies selected from diverse clusters could produce greater heterosis needed for higher growth and suitable for products.
