谷子旱后的补偿效应研究

Compensation effect of millet after drought.

通过对谷子旱后的生理表现、干物质积累速率、水分利用效率、经济系数的研究，认为谷子存在旱后补偿效应这一适应性生理生态现象．实验结果表明，前期曾受旱的处理表现出超速生长的趋势，相对日均干物质增长速率显著高于一直处于同一供水水平的处理，经过加速生长能部分甚至全部补偿前期干旱所造成的干物质上的损失．前期干旱对谷子的生理影响具有延续性，后期增加供水水平后，同等供水水平的处理中曾经历干旱的表现出较高光合速率和叶绿素含量．谷子的旱后补偿效应还表现在能高效地利用有限的水和干物质以形成种子．在我国西部半干旱区，相对夏季作物而言。

Studies on the physiological performance, dry matter accumulation rate, water utilization efficiency and economic coefficient of millet after drought show that millet had compensation effect after drought, which was a kind of adaptive physiological phenomenon. In the treatment that millet had been drought earlier, millet showed a tendency of extra growth, and its relative daily accumulation rate of dry matter was higher than other treatments at the same water supply level. The dry matter loss could be compensated partly or even completely through extra growth. The physiological impact of earlier drought on millet had the character of continuity. After subsequent increasing water supply, the treatment that had been drought earlier showed a higher net photosynthetic rate and a higher chlorophyll content in leaf . The compensation effect of millet also showed a higher efficiency in utilizing limited water and dry matter to produce grain. In the west semiarid area of China, autumn cropos with the character of extra growth after drought adapt the distribution of natural precipitation, comparing with summer crops.