Effect of seed size on seed germination and seedling vigour index of Abies spectabilis (D. Don) spach

Germination trial was conducted to study the effect of seed size on germination behaviour and seedling vigour index of Abies spectabilis - an important high altitude conifer of Western Himalayan. The seeds of A. spectabilis collected from Kalabagh forest in Shimla district (H. P.) were segregated into three different seed size classes viz., small (6 mm - 7 mm x 3 mm - 4 mm), medium (7 mm - 8 mm x 4 mm - 5 mm) and large (> 8 mm x > 5 mm). Maximum germination40.50% was recorded in large seeds and minimum of 12.00% in small seeds. Maximum germination capacity 42.75% was recorded in large seeds which is significantly better than 17.00% which was recorded in small seeds. The highest seedling vigour index of 354.05 was recorded in large seeds followed by 253.79 in medium seeds and minimum of 72.17was recorded in small seeds in a decreasing order. Hence, the study concluded that seeds of A. spectabilis should be segregated after their collection from the field on the basis of size and only large seeds having size >8mm x >5mm should be use for getting better germination and vigorous growth of seedlings in the nursery.