微生物菌肥对盐碱地向日葵减施氮肥效应研究

Study on the effect of microbial fertilizer on reducing nitrogen fertilizer application on Helianthus ann⁃uus L.in saline-alkali Soil

[目的]目前微生物菌肥已在改良土壤养分、提高作物产量方面取得良好的应用效果,但河套灌区关于微生物菌肥对作物生长及减施氮肥效应的研究较少。本研究开展微生物菌肥对作物生长及减施氮肥效应的田间试验,旨在为河套灌区农业绿色发展提供科学支撑。[方法]通过设置生物菌肥施用梯度(3000、6000、9000 kg·hm^(-2))和氮肥减施梯度(减氮15%、减氮30%、减氮45%)的不同组合模式,测定作物产量、作物生育性状(株高、茎粗、叶绿素、盘径等)、土壤理化性质(土壤全盐含量、碱化度、含水率和孔隙度等)及微生物结构和多样性等指标,利用SPSS22进行单因素方差分析(One-way ANOVA)和Duncan多重比较检验法分析盐碱化土壤施入微生物菌肥后向日葵产量、土壤理化及生物性状的变化规律。[结果](1)当氮肥减量15%和30%时,向日葵产量、土壤含水率、土壤孔隙度随着微生物菌肥用量增加而增加;(2)当氮肥减量45%时,孔隙度随着菌肥用量增加而减小,向日葵产量受到抑制;(3)微生物菌肥的施用显著降低土壤全盐含量和碱化度,但对土壤pH影响不显著。(4)施加菌肥3000和6000 kg·hm^(-2)水平的菌肥添加有助于土壤微生物群落多样性的提升。[结论]在施用微生物菌肥的情况下,可适当削减氮肥的使用量,但氮肥减量不宜超过45%。

[Objective]At present,microbial fertilizers have shown good results in soil nutrient improvement and crop yield en-hancement.However,there are limited studies on the effects of microbial fertilizers on crop growth and reducing nitrogen appli-cation in the Hetao irrigation area.In order to provide scientific support for sustainable agriculture in Hetao irrigation district,field experiments were carried out to investigate the effects of microbial fertilizer on crop growth and reducing nitrogen applica-tion.[Methods]Field trials were conducted using different combinations of microbial fertilizer application gradients(3000,6000,and 9000 kg·hm^(-2))and nitrogen fertilizer reduction gradients(15%,30%,and 45%).Various parameters,including crop yield,crop growth traits(plant height,stem diameter,chlorophyll,disk diameter,etc.),soil physical and chemical prop-erties(soil total salt content,alkalinity,water content,porosity,etc.),microbial structure and diversity,were measured.One-way ANOVA analysis and Duncan's multiple comparison test using SPSS22 were conducted to analyze the variation in the yield of H.annuus L.,soil physicochemical and biological properties after applying microbial fertilizer in saline-alkali soil.[Re-sults](1)When nitrogen fertilizer was reduced by 15%and 30%,the sunflower yield,soil moisture content,and soil porosity increased with the increase of microbial fertilizer dosage.(2)When nitrogen fertilizer was reduced by 45%,the porosity de-creased and sunflower yield was inhibited with the increasing application of bacterial fertilizer.(3)The application of microbial fertilizer significantly reduced soil total salt content and alkalinity,but had no significant effect on soil pH.(4)Application of microbial fertilizer at levels of 3000 and 6000 kg·hm^(-2) of improved the soil microbial community diversity.[Conclusion]Under the application of microbial fertilizers,nitrogen fertilizer application can be appropriately reduced,but the reduction of nitrogen fertilizer should not exceed 45%.