Effect of seed source variation on seed and seedling characteristics of Toona ciliata: A promising timber tree species of western Himalaya

Based on seed polymorphism and average growth performance of progenies of Dhelu, Solan, Darang, and Gagal recorded as ideal seed sources for healthier seedling production. Test of significance (‘t’) computed between per cent of sound seed and various seed characters revealed that the seed source significantly enhanced root and shoot lengths, root collar diameter and dry weight of seedlings. Larger food reserves in the seed might have allowed more pre-photosynthetic growth of the seedlings that emerged from heavy seeds. Since the seedlings of all the sources were grown at the same place, variations occurring in seedling characters might be attributed to genetic differences. Results indicate that the root and shoot lengths come under genetic control, whereas germination percentage falls under environmental influence. Besides this, heritability (h²), genetic advance and genetic gain were again higher for root and shoot lengths, indicating that these characters are under strong genetic control. This suggests that judicious screening/selection of seed sources considering these traits could be meaningful for the improvement of Toona ciliata.