Clonal variation for seed germination in teak (Tectona grandis Linn. f.)

Large variations for per cent seed germination and dormancy release pattern were observed among half-sib families of eight teak clones-derived from a 20-year-old clonal seed orchard. Overall germination percentage was on the lower side. Although initial germination was influenced by traits such as fruit diameter and 100 fruit weight, germination at 140 days after sowing was independent of these traits. Interestingly, there was a perfect negative association between age of the ortet (mother tree) from which the clonal material was originally derived and the per cent germination of its progeny supporting 'genetic load accumulation with-age' hypothesis. Hence care must be taken not to include clones of older ortets while establishing future clonal seed orchards.