Seed Germination in Barringtonia acutangula: A Floodplain Tree From North East India

Abstract

Flooding is a natural and periodic disturbance and the floodplain species possess numerous adaptation strategies to cope with the periods of waterlogging. Barringtonia acutangula, a tree that grows on the bank of the river is uniquely adapted to the aquatic conditions. The species has been managed by floodplain people of the North East India for their livelihood security through fish capture and trade over millennia. It is important to understand the seed germination behaviour of the species for better management of the Barringtonia trees. We describe seed germination in Barringtonia acutangula in relation to different seed mass category and pre-sowing treatments, under nursery and laboratory conditions. Depending on the variation in seed mass, seeds were classified into three weight classes namely: heavy (≥3g), intermediate (2 -3g) and light (1-2g). Seeds from different weight classes showed significant difference in the periodicity of seedling emergence (χ2 = 9.83, p < .01). Heavy seeds exhibited better germination characteristics viz. high shoot length (F= 13.63, p <0.01), high root length (F = 2.97, p < 0.05), high dry weight per plant (F = 4.96, p < 0.05) except the number of leaves per plant (F= 1.15, p <0.05) over other seed categories. Seed weight exhibited positive correlation with seedling growth characteristics (R2 = 0.84- 0.97). Pre-sowing treatments affected seed germination (F= 19.27 p <0.01) and seedling emergence time (F= 28 p<0.01). Study reveals that heavy seeds are important for better management of floodplain Barringtonia forest.