Seedling Emergence and Growth of Terminalia superbaEng. EL. Diels under Different Light Conditions

چکیده

One of the ecological factors essential to the growth and survival of tropical forest tree species is availability of light in terms of amount, quality and duration. The effects of direct light (DL), low light  (LL) and medium light (ML) on seed germination and seedling growth of Terminalia superbawere investigated. Seeds were soaked in  water under ambient conditions for 24 h and sowed under the three light conditions. Germination occurred earlier at 13 days after sowing (DAS) under LL and DL but ML caused a delay till 15 DAS while germination was completed at 25, 29 and 33 DAS under LL, DL and ML respectively. The seedling height increased over the assessment period and varied significantly among the light conditions with LL producing the tallest plants. Mean collar diameter
increased over the assessment period and was highest under LL except at week 12 but the values did not differ significantly from the other light conditions. The number of leaves increased and ranged between 7.11 and 15.56, 8.11 and 17.00 and 8.78 and 16.89 under DL, ML and LL respectively but the highest values under ML were similar to the other light conditions. The good germination and growth performance suggest that Terminalia superba would withstand shade at the early stage and can be incorporated into agroforestry and mixed plantation systems.