水肥热耦合对滴灌青贮玉米生长、光合及产量的影响

Effects of Water,Fertilizer and Heat Coupling on Growth,Photosynthesis and Yield of Silage Maize Under Drip Irrigation

针对宁夏玉米水肥热利用率低的问题,开展了滴灌土壤水肥热耦合对青贮玉米生长、光合及产量的影响研究。采用三因素三水平正交试验,利用极差分析和方差分析,得出了水肥热耦合影响青贮玉米各项指标的主次顺序、显著性及最优组合方案。结果表明:三因素影响鲜生物产量、籽粒产量的顺序均为灌溉定额>追肥量>根区温度;灌溉定额和追肥量对鲜生物产量影响显著,灌溉定额和追肥量对籽粒产量影响极显著,根区温度对鲜生物产量和籽粒产量影响不显著。青贮玉米的株高、茎粗、叶面积指数、净光合速率、蒸腾速率、鲜生物产量及籽粒产量随着灌溉定额、追肥量和根区温度的增大而增大。在生育期内降雨量为148 mm、地下水埋深1.66 m条件下,综合考虑水肥热耦合对滴灌青贮玉米生长、光合及产量的影响,确定三因素最优水平组合为A3B3C2,即灌溉定额为2520 m^(3)/hm^(2)、追肥量为594 kg/hm^(2)(纯N为273.24 kg/hm^(2))、覆普通地膜,鲜生物产量和籽粒产量均最高,鲜生物产量为96638 kg/hm^(2),比CK增产14.96%;籽粒产量为14927 kg/hm^(2),比CK增产13.25%。可为引黄灌区青贮玉米高效节水灌溉土壤水肥热调控制度推广提供理论依据。

In order to solve the problem of the low water-fertilizer-heat utilization rate of border irrigation maize,the effects of soil water and fertilizer heat coupling on the growth,photosynthesis,and yield of drip irrigation silage maize were studied.By using three factors and three levels orthogonal test,range analysis and variance analysis,the primary and secondary order,significance and optimal combination scheme of water,fertilizer,and heat coupling effect on silage maize were obtained.The results showed that the order of the three factors affecting fresh biomass and grain yield was irrigation quota>topdressing amount>root zone temperature.Irrigation quota and the topdressing amount had a significant effect on fresh biomass yield,irrigation quota and the topdressing amount had an extremely significant effect on grain yield,and the root-zone temperature had no significant effect on fresh biomass yield and grain yield.The plant height,stem diameter,leaf area index,net photosynthetic rate,transpiration rate,fresh biomass,and grain yield of silage maize increased with the increase of irrigation quota,topdressing amount,and the root-zone temperature.Under the condition of rainfall of 148 mm and groundwater depth of 1.66 m during the growth period,the effects of water,fertilizer,and heat coupling on the growth,photosynthesis,and yield of drip irrigation silage maize were comprehensively considered,and the optimal combination of three factors was determined as A3B3C2,i.e.,irrigation quota of 2520 m^(3)/hm^(2),topdressing amount of 594 kg/hm^(2)(pure N of 273.24 kg/hm^(2)),and mulching with ordinary plastic film.The fresh biomass and grain yield were the highest,and the fresh biomass was 96638 kg/hm^(2),which was 14.96% higher than that of CK.The grain yield was 14927 kg/hm^(2),13.25% higher than CK.This study can provide a theoretical basis for the promotion of soil water,fertilizer and heat regulation system for efficient water-saving irrigation of silage maize in Yellow River irrigation area.