LATE MATURATION CHANGES IN SAL (SHOREA ROBUSTA) SEED AND THEIR EVALUATION AS INDICES FOR PROPER TIMING OF SEED COLLECTION

Abstract

Sal (Shorea robusta) seeds are best collected approximately 69 days after anthesis (DAA) when fruit coat colour changes from greenish yellow to dark brown. The high germination indicated that physiological maturity was reached around this time. At this stage of development fruit volume, weight, cotyledonary petiole length and germination value were at their maximum and electrical conductivity of seed leachates and mean germination time were at their minimum. In sal, the initial manifestation of germination is through elongation of cotyledonary petiole, which bursts through the pericarp and carries the radicle/ plumule axis to the ground. The petiole length may therefore serve as a potential vigour index for sal seed.