Effects of Flooding on Leaf Water Potential and Stomatal Resistance Inbruguiera Gymnorrhiza(l.) Lam

SUMMARY The effects of 10, 20, 40 and 80 days of flooding on stomatal responses in the halophyte,Bruguiera gymnorrhiza(L.) Lam were investigated. Measurements were made of leaf water potential and stomatal resistance (rg) during the period of flooding, and continuing for 12 to 14 days after its termination. Generally, plants flooded for prolonged periods had lower leaf water potentials than the controls both during and after flooding. Prolonged flooding also resulted in higherrgduring flooding and continuing for 8 to 10 days afterwards. Leaf water potentials decreased with increase in the duration of flooding. Decrease in leaf water potential was also associated with an increase inrg. Prolonged flooding also resulted in ultrastructural modifications. The chloroplasts had smaller grana and the lamellae were considerably swollen. There also appeared to be some degradation of thylakoid membrane structure.