Dry Matter Production and Root System Development of Rice Cultivars under Fluctuating Soil Moisture
Dry Matter Production and Root System Development of Rice Cultivars under Fluctuating Soil Moisture
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土壤水分波动下水稻品种的干物质生产和根系发育
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
J. R. Pardales
中科院分区：
文献类型：
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作者：
Dionisio M. Bañoc;A. Yamauchi;A. Kamoshita;L. Wade;J. R. Pardales
摘要干旱区水稻多生长在波动的土壤水分条件下。我们研究了不同水稻品种的干物质生产，根系发育和水分利用对土壤水分变化的反应。水稻植物在温室条件下在聚氯乙烯管中生长。播后持续干旱严重抑制了所有供试品种的地上部干物质生产、分蘖发育、节根发育和水分吸收。当植物经历土壤淹没之前，暴露于干旱，所有的品种表现出较高的干物质生产比他们的良好浇水的同行。品种差异清楚地指出，在这些植物被干旱后复水的生长反应。以充分浇水对照为基础，IRAT 109和KDML 105植物通过增强侧根发育提高了转化有效干物质以增加其总根长的效率。在后者中，然而，根的干重也增加，所以没有根吸水。在Dular，干旱植物没有表现出明显的反应，在根系发育和水分吸收复水，而其新梢生长受到更严重的抑制比其他品种。这些结果表明，根系结构的表型可塑性所表现出的促进侧根的发育和新的节根的产生发挥了关键作用，在水稻生长在变化的土壤水分水平。
Abstract Rice plants in the rainfed areas are mostly grown under fluctuating soil moisture. We examined responses in dry matter production, root development and water use to changing soil moisture in diverse rice cultivars. Rice plants were grown in polyvinyl chloride tubes under glasshouse conditions. Progressive drought right after planting greatly inhibited the shoot dry matter production, tiller development, nodal root development and water uptake in all cultivars tested. When the plants experienced soil submergence before being exposed to drought, all the cultivars exhibited higher dry matter production than their well-watered counterparts. Cultivar differences were clearly noted in the growth responses to rewatering after these plants were droughted. With well–watered control as basis, IRAT 109 and KDML 105 plants increased efficiency in converting available dry matter to increase their total root length by means of enhanced lateral root development. In the latter, however, the dry weight of roots also increased and so did root water uptake. In Dular, droughted plants did not show a clear response in terms of root development and water uptake to rewatering while its shoot growth was much more severely inhibited than the other cultivars. These findings suggest that phenotypic plasticity in the root system structure exhibited by promoted lateral root development and new nodal root production play a key role in the growth of rice under changing moisture level in the soil.