STRATEGY FOR ENVIRONMENTAL ADAPTATION IN AQUATIC PLANTS

1. 我们从自然栖息地和我们的温室中收集了香蒲（Typha latifolia L.）。箭头植物（Sagittaria pygmaea Miq.）由宇都宫大学杂草科学中心提供。设计了一种氮气连续流系统，通过压力调节器和流量控制阀，从钢瓶中引入纯净的氮气，用于处理浓度低于100ppm的低氧植物。香蒲芽ADH活性在缺氧处理6 h内显著升高，并在10 d内保持最大值。缺氧促进了箭头芽的伸长，ADH活性随之升高。结果表明，缺氧条件下ADH活性的升高与其对缺氧的耐受性有关。对香蒲和箭头芽的体内翻译产物进行了二维电泳分析。缺氧处理对香蒲芽蛋白质合成的影响与箭头芽有很大不同。香蒲中多肽的合成在厌氧条件下几乎停止2小时。厌氧处理8小时后新多肽的合成情况。另一方面，在箭头块茎中，许多需氧合成的多肽在厌氧条件下被翻译。活性翻译可能与缺氧条件下叶片伸长的促进有关。

1. We collected cattail plants (Typha latifolia L.) from the natural habitat and also our green house. The arrowhead (Sagittaria pygmaea Miq.) plants were supplied from the Weed Science Center of Utsunoimiya University. We made a continuous N_2 gas-flow system, in which pure N_2 gas from a cylinder was introduce through a pressure regulater and a flow controller valve in order to treat the plants with low O_2 concentratiions less than 100ppm.2. The ADH activity of cattail buds increased significantly within 6 h of anoxic treatment and kept a maximal value for 10 days. Moreover, the elongation of arrowhead bud was promoted under anoxia with concomitant increase in the activity of ADH.The results suggested that increase in ADH activity under anoxia is related to the tolerance to anoxia.3. We analyzed in vivo translation products of cattail or arrowhead buds by 2-D electrophoresis analysis. The effects of anoxic treatment on protein synthesis in cattail buts were quite different from that in arrowhead buds. Synthesis of aerobical polypeptides in cattail buts were almost stopped under anaerobic conditions for 2 hours. Synthesis of new polypeptides stated after 8hours of anaerobic treatment. In arrowhead tubers, on the other hand, many polypeptides synthesized aerobically were translated unde anaerobic conditions. The active translation may be related for the promotion of leaf elongation under anoxia.