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在印度旁遮普的霍希亚布尔地区,随机分组设计细叶桉各种生长参数,评价18个基因型株系在3年中的生长情况,比较了无性系种子园和未知种源的种子长成的植株.结果表明,各株系株高、胸径和主干高均存在显著差异.株高和主干高度的广义遗传力处于中、低水平.株高和主干高的遗传增益随树龄的增加而增加.株高3年平均遗传增益值最大(159.60%),胸径次之(110.97％),主干高度的平均遗传增益值最低(70.34％).第2,3年时,与其他株系比较,株系17rn的胸径最大,株系14和5次之.随树龄的增加,株系5胸径呈增加趋势,主干高最优.第2,3年时,株系11的胸径值在18rn个株系中从第9位分别升高到8位和第3位,主干高也从第9位升高到第4和第2位.株系6和10各项参数值均最差.株系17,14和5最适合商业化种植.“,”Eighteen clones of Eucalyptus tereticornis (Sm.) were evalu-ated for three years by adopting randomized block design for various growth parameters at Hoshiarpur, Punjab, India and compared with two checks. Significant variations were recorded for height, diameter at breast height (DBH) and clear bole height (CBH). The broad sense heritability was low to moderate for both height and CBH. The genetic gain for height and CBH increased substantially per se with the increase in age of trees. The average genetic gain for three years was recorded maximum for height (159.60%) followed by DBH (110.97%) and CBH (70.34%). Clone 17 attained maximum DBH over other genotypes for second and third year followed by clones 14 and 11. Clone 5 showed an upward trend for DBH and maintained its superiority for CBH as the age of the tree increased. Similarly, clone 11 changed its ranking from 9th to 8th to 3rd for DBH and from 9th to 4th to 2nd for CBH, respectively for the age of one, two and three years. Nonetheless, clones 6 and 10 per-formed poorly for all the characters studied. Clones 17, 14 and 5 were found to be the most promising clones for commercial deployment.