不同类型保水剂对旱作谷子水分利用的影响

Effects of different types of water retaining agents on water use of rainfed millet

为解决内蒙古黄土高原区干旱缺水导致的谷子出苗难、水分利用效率和产量低而不稳等一系列问题,以金苗K1谷子品种为试验材料,采用智动载体、聚丙烯酰胺(PAM)、高分子吸水性聚合物(SAP)、膨润土、华申农林保水剂5种保水剂,每种保水剂设置3个施用量处理,以不施保水剂为对照(CK),进行随机区组试验。在谷子生育期内研究不同保水剂及用量对谷子出苗率、土壤蒸发量、籽粒产量及水分利用效率的影响。结果表明:施用5种保水剂均减少了土壤水分蒸发量,提高了谷子成熟期的生物量积累、产量和水分利用效率。在智动载体和PAM施用量分别为37.5kg/hm^(2)和75kg/hm^(2)时,土壤水分蒸发量较对照分别减少25.31%和26.40%;谷子地上部生物量较对照分别提高了28.47%和19.92%;籽粒产量和产量水分利用效率较对照分别提高20.54%、20.42%和25.0%、25.5%;经济效益均表现最高,减蒸增效作用均强于膨润土、华申农林保水剂和SAP。

To address a series of problems such as difficult seedling emergence,low water utilization rate and low and unstable yield of millet caused by drought and water shortage in Inner Mongolia Loess Plateau,five water retention agents,namely,wise motion carrier,polyacrylamide(PAM),high molecular absorbent polymer(SAP),bentonite,and Hua-Shen agroforestry water retention agent,were used as test materials,and three level treatments were set for each water retention agent,with no water retention agent applied as control,in a randomized zone group test.The effects of different water retention agents and dosages on seedling emergence,soil water content,yield and water use efficiency were studied during the millet growing period.The results showed that the application of all five water retention agents reduced soil water evaporation,increased biomass accumulation at maturity,and improved yield and water use efficiency.At the application rates of 37.5kg·hm^(-2) and 75kg·hm^(-2) for wise motion carrier and PAM,respectively,the soil water evaporation was reduced by 25.31%and 26.4%in 2 years averagely,respectively,compared with the control,and the above-ground biomass of millet was increased by 28.47%and 19.92%,and the grain yield and water utilization efficiency were increased by 25.54%,20.42%and 25%,25.5%,respectively,and the economic benefit reached the maximum in the second year,compared with the control.The effect of reducing water and increasing water use efficiency foe wise motion carrier and PAM were stronger than those of bentonite,Hua-Shen agroforestry water retention agent and SAP.