西南喀斯特地区小麦节水灌溉试验研究

Water-Saving Irrigation Experiment of Wheat in Karst Area in Southwest China

为探求适合西南喀斯特地区的小麦节水灌溉制度,以高效利用农田水资源,在小麦各个生育期设计不同的土壤含水率上下限值,通过大田露地及测坑试验,测定了不同水分处理下的小麦产量及水分生产率。结果表明:小麦对缺水的敏感性,是开花期大于产量形成期,产量形成期大于营养生长期;小麦水分生产率随着灌水量的增加而减小;小麦的产量和灌溉定额成明显的二次抛物线型关系,当灌水量小于某一临界值时,产量会随着水量的增加而增加,但当超过临界值之后,产量反而会随着水量的增加而减少。该研究可为西南喀斯特地区的小麦节水高效灌溉制度提供理论参数。

In order to find out the water-saving irrigation system of wheat that suit to karst area in southwest China,an upper and lower limit value for the water content in soil at different vegetation period of wheat were designed.The water productivity and yield under different water conditions were determined according to the open air and survey-pit test.The results showed that the most sensitive period to hydropenia of wheat was in a order of florescence 〉grain-filling period vegetative period;the water productivity decreased with the increasing water volume;there were parabola relationship between yield and volume of water,while the water volume was less than the definite value,the wheat yield increased with the increasing water volume,while the water volume was more than the definite value,the yield decreased.These results might provide some scientific clew for water-saving and efficient irrigation in karst area in southwest China.