Melia dubia is one of the most important industrial tree species in the South East Asia. In last few decades, the populations of M. dubia has rapidly expanded in the Indian sub-continents, leading to an increase in the genetic diversity of species. However, very less information is available on intra-specific variation in Melia under the Indian subcontinent. Therefore, a present investigation was undertaken, to assess the level of diversity in seed and saplings of the Melia populations (ecotypes) collected from three agro-ecological regions of India. Results revealed that the seed and saplings of all the ecotypes are significantly different for all the traits, except for number of branches per plant, and the maximum variability was recorded in germination percentage, seed weight, internodal length, and sapling height of the species. The high heritability for seed weight (0.99), length (0.99), and width (0.97), and germination percentage (0.99) indicated that selection and genetic gain for these traits would be effective during the commencement of improvement program. Trait association analysis explained that higher seed weight significantly reduced sapling height, collar diameter, number of leaves per plant, internodal length, petiole length, and germination percentage (r = −0.86; p < 0.001) that ultimately reduced the seedling vigor in Melia dubia. Interestingly, the number of branches per plant were not associated with any of the morphological traits. The first principal component explained 50.09% of the entire variation and all the traits contributed greatly to the variation for this principal component, except for number of branches, leaf width and seed length. The clustering approach assorted geographic variation of M. dubia populations into three main sub-clusters i.e. South, North, and North East populations each consisting of five, seven and one populations (including cultivar), respectively. Among different ecotypes, Bahumukhi, Varsha and US Nagar seed sources outperformed all others in seedling vigour (sapling height) and rest of the growth parameters. Overall, findings explained that considerable scope exists for the development of superior planting material of M. dubia through exploration of seeds and selection at the early seedling stage.

Melia dubia是东南亚最重要的工业树种之一。在过去的几十年里，M. dubia的种群在印度次大陆迅速扩大，导致物种遗传多样性的增加。然而，关于印度次大陆下Melia 的种内变异的信息非常少。因此，目前进行了一项调查，以评估Melia种子和树苗的多样性水平从印度的三个农业生态区收集的种群（生态型）。结果表明，除每株分枝数外，所有生态型的种子和树苗在所有性状上均存在显着差异，最大变异性记录在该物种的发芽率、种子重量、节间长度和树苗高度。种子重量 (0.99)、长度 (0.99) 和宽度 (0.97) 和发芽率 (0.99) 的高遗传力表明这些性状的选择和遗传增益在改良计划开始期间将是有效的。性状关联分析解释说，较高的种子重量显着降低了树苗高度、衣领直径、每株植物的叶片数、节间长度、叶柄长度和发芽率（r = -0.86；p < 0.001) 最终降低了Melia dubia的幼苗活力。有趣的是，每株植物的分枝数与任何形态特征无关。第一主成分解释了整个变异的50.09%，除分枝数、叶宽和种子长度外，所有性状对该主成分的变异贡献很大。聚类方法对M. dubia 的地理变异进行分类种群分为三个主要亚群，即南方种群、北方种群和东北种群，每个种群分别由五个、七个和一个种群（包括栽培品种）组成。在不同的生态型中，Bahumukhi、Varsha 和 US Nagar 种子来源在幼苗活力（树苗高度）和其他生长参数方面优于所有其他来源。总体而言，研究结果解释说，通过在幼苗早期探索种子和选择，开发M. dubia优质种植材料存在相当大的空间。