By simulating the conditions of water stress,the chlorophyll content and constitutes of Lersia herxandra was determined after stressed for 7,14,21,28,35,42 and 49 days under submerged and waterlogged conditions.The results showed that the content of chlorophyll a was higher than that of chlorophyll b.Compared with the check,the chlorophyll content under submerged condition declined to a relative lower level with the time extension of stress,while it fluctuated within a certain range under waterlogged condit...