生物肥料HZ-24对黄芪生长及土壤微生物数量和酶活性的影响

Effect of bio-fertilizer HZ-24 on Astragalus mongholicus growth,soil microbial quantity and enzyme activity

通过盆栽试验研究生物肥料HZ-24对黄芪的促生效果及土壤根际微生物数量和土壤酶活性的影响,初步探讨生物肥料HZ-24增产的机理,为生物肥料HZ-24的推广应用提供依据。本研究以蒙古黄芪为试验材料,设置了对照、载体、生物肥料HZ-24、化肥处理(NP)、化肥+载体(NP+载体)、化肥+生物肥料HZ-24(NP+生物肥料HZ-24)6个处理,在收获时采集根际土壤,测定土壤中可培养微生物数量、脲酶和磷酸酶活性,分析不同肥料处理对黄芪根际土壤微生物数量与土壤酶活的影响。结果表明,生物肥料HZ-24对黄芪根直径、根干重有显著促进作用。与不施肥对照相比,根干重增加了40.8%,根直径增加36.7%;与化肥处理相比,化肥配施生物肥料HZ-24根干重增加16.2%,根直径增加19.2%。生物肥料HZ-24可以增加根际土壤细菌、放线菌的数量,减少真菌的数量,与不施肥对照相比,细菌、放线菌分别增加37.3%、22.7%,真菌减少19.3%;与化肥处理相比,化肥配施生物肥料HZ-24处理细菌、放线菌分别增加了23.7%、14.6%,真菌减少了37.1%。生物肥料HZ-24能够增加土壤脲酶、酸性磷酸酶、碱性磷酸酶活性,与不施肥对照相比,脲酶、酸性磷酸酶、碱性磷酸酶、中性磷酸酶活性分别增加24.2%、25.9%、18.1%、44.2%;与单施化肥处理相比,化肥配施生物肥料HZ-24处理的脲酶、酸性磷酸酶、碱性磷酸酶、中性磷酸酶活性分别增加45.7%、6.7%、24.8%、54.0%。综上所述,生物肥料HZ-24增产的机理主要是生物肥料中含有的假节杆菌可以改变黄芪根系微生物菌落结构,使根际土壤细菌、放线菌的数量增加,真菌的数量减少,使土壤向细菌型、休耕性转变;施用生物肥料HZ-24能够显著的增加土壤脲酶、酸性磷酸酶、碱性磷酸酶活性;还可以增加根瘤重,增强了根瘤的固氮能力,有利于农作物根系对养分的吸收。

A pot experiment was conducted to study the effect of bio-fertilizer HZ-24 on the growth of Astragalus mongholicus and soil rhizosphere microbial quantity and soil enzyme activity,to explore the mechanism of bio-fertilizer HZ-24 in yield increasing and provide a basis for bio-fertilizer HZ-24 application.Astragalus mongholicus was planted in the experiment with six treatments:control,carrier,bio-fertilizer HZ-24,fertilizer treatment(NP),fertilizer+carrier(NP+carrier),fertilizer+bio-fertilizer HZ-24(NP+bio-fertilizer HZ-24);then collected samples from the rhizosphere soil at harvest stage;finally analyzed the number of cultivable microorganisms,urease and phosphatase activities in the soil as well as the effects of different treatments on the number of soil microbes and soil enzyme activities in the rhizosphere soil of Astragalus mongholicus.The results showed that HZ-24 significantly promoted root diameter and root dry weight of Astragalus mongholicus.Compared with the control without fertilization,root dry weight increased by 40.8%and root diameter increased by 36.7%.Compared with chemical fertilizer treatment,the dry weight and root diameter of HZ-24 increased by 16.2%and 19.2%,respectively.Biological fertilizer HZ-24 can increase the number of bacteria and actinomycts in rhizosphere soil and reduce the number of fungi.Compared with the control without fertilization,bacteria and actinomycts increased by 37.3%and 22.7%,while fungi decreased by 19.3%,respectively.Compared with the chemical fertilizer treatment,the bacteria and actinomycete increased by 23.7%and 14.6%,and the fungi decreased by 37.1%,respectively.The activities of urease,acid phosphatase,alkaline phosphatase and alkaline phosphatase in soil increased by 24.2%,25.9%,18.1%and 44.2%,respectively,compared with the control without fertilization.The activities of urease,acid phosphatase,alkaline phosphatase and neutral phosphatase increased by 45.7%,6.7%,24.8%and 54.0%,respectively,compared with the single application of chemical fertilizer HZ-24.In conclusion,the mechanism of increasing yield of HZ-24 biofertilizer is mainly Pseudarthrobacter spp.that contained in the biofertilizer can change the microbial colony structure of astragalus root,increase the number of bacteria and actinomycetes in rhizosphere soil,and decrease the number of fungi,so that the soil becomes bacterial and fallow.Applying biological fertilizer HZ-24 can significantly increase soil urease,acid phosphatase and alkaline phosphatase activities.It can also increase the nodule weight and enhance the nitrogen fixation ability of nodule,which is conducive to the absorption of nutrients by crop roots.