半干旱区旱地不同覆盖方式对糜子耗水和产量的影响

为探讨半干旱区旱地不同覆盖方式对糜子耗水特征和产量的影响,测定了全膜覆土穴播(PMS)、全膜覆盖穴播(PM)和露地穴播(CK)3种不同处理的糜子发育动态、0—200cm土壤水分季节变化、糜子地上生物量动态、产量和耗水量。2a的试验结果表明,地膜覆盖后糜子营养生长期缩短,生殖生长时期延长,但全生育期缩短;PMS处理的糜子的生育期较CK缩短12～13d,较PM延长10～11d。地膜覆盖使糜子拔节前0—200cm土层的土壤含水量增加,随糜子生育进程的推进,3种处理的耗水量依次为:PM>PMS>CK。在抽穗前,PM的地上生物量最大,其次为PMS,CK最小;在收获期,PMS的生物量和籽粒产量均显著高于PM。PM和PMS的产量较CK分别在2009和2010年提高了83.53%和64.56%,115.51%和84.47%;与PM处理相比,PMS的糜子产量在2009年和2010年提高了17.42%,18.18%,但两个处理的土壤耗水量在2a均无显著差异。因此,通过覆盖降低棵间蒸发是提高旱地糜子产量和水分利用效率(WUE)的主要途径。通过覆盖方式的选择来调控糜子的发育进程和耗水过程,对提高糜子产量和WUE也有重要意义。

Effects of Different Mulching Methods on Water Consumption and Yield of Millet in Rain-fed Semiarid Area

In order to understand the effects of different mulching methods on water consumptive characteristics and yield of millet,the two-year field experiment involved in three treatments: whole field surface plastic mulching and soil covered on plastic film(PMS),whole field surface plastic mulching(PM) and uncovered treatment(CK),were carried out.The growth stages,seasonal change of soil water content in 0—200 cm soil profile,dynamics of aboveground biomass,grain yield and water consumption of millet were measured in this field experiment.The results showed that the plastic mulching shortened the vegetative growth stage,elongated reproductive growth stage,caused the whole growth stage to shorten.The growth stage of millet in PMS treatment shortened by 12～13 days and elongated by 10～11 days compared with CK and PM treatment,respectively.The soil water content in 0—200 cm profile increased in PM and PMS treatment before millet heading,the vegetative growth of millet also was promoted compared with CK.With the millet growth,there was a significant difference in water consumption between three treatments,which followed the sequence as PM>PMS>CK.Conversely,the change of soil water storage followed the sequences as CK>PMS>M.Before millet heading,the aboveground biomass in PM treatment was higher than that in PMS treatment,and was lowest in CK.However,the aboveground biomass in PMS treatment was significant higher than those in PM and CK,and it was also lowest in CK in harvest stage.The yield of millet in PM and PMS treatment increased by 83.53% and 64.56%,115.51% and 84.47% in 2009 and 2010,respectively,compared with CK.Additionally,the yield of millet in PMS treatment increased by 17.42% and 18.18% in 2009 and 2010,respectively,compared with PM treatment.However,the soil water consumption was not significantly different between PMS and PM treatments in both experimental years.was indicated that plastic mulching decreased soil surface evaporation,which was an efficient way to increase millet yield and water use efficiency(WUE).Selecting the appropriate mulching method could regulate millet developmental and water consumptive process,which is also important to increase yield and water use efficiency of millet.