Abstract

Thangaraja, A.1* and Ganesan, V.

Terminalia paniculata is a deciduous tree widely distributed in tropical semi-evergreen and moist deciduous forest. Flowers of T. paniculata have ten stamens, which remain inside the bud and anthesis is carried out at different times of the day. Pollen grains are medium spherical, tricolpate 17 m in diameter, smooth exine and yellow in colour. The pollen: ovule ratio approximated 16,000: 1. Pollination efficiency was increased daily, from first day of flower opening (0.000076), reaching the maximum on third day (0.00083) and there was no pollen deposition on the fourth day. To effectively assess in- vitro pollen viability in T. paniculata, an optimized germination medium (30% sucrose with Brewbaker and Kwak’s medium) was developed. Pollen grains stored under cryopreservation (-20oC) had prolonged viability. Using the hand pollination for testing the in-vivo viability of pollen grains the maximum number of fruit set was obtained in the fresh pollen grains (0 h – pollen collected at the time of anthesis) on the stigma. Afterwards, increase in the age of the pollen decreased the fruit set. After 15 h of anthesis, the pollen grains lost their viability and there was no fruit set. The current findings will be useful in studying, pollen – pistil interactions, gene flow and heterozygosity of the T. paniculata populations