PGPR生物肥对甜樱桃(Cerasus pseudocerasus)根际土壤生物学特征的影响

Effect of PGPR Fertilizer on Biological Characteristics in Cerasus pseudocerasus Rhizosphere

利用保绿法和萝卜子叶增重法从7年生甜樱桃[Cerasus pseudocerasus(Lindl.)G.Don]根际土壤中,筛选具有促生作用的植物根际促生细菌YT-3(PGPR),以发酵好的鸡粪(DCM)为吸附载体制成甜樱桃专用的PGPR生物肥料(YMF),对比研究了YMF、普通生物肥(NMF)和DCM对樱桃根系和根际土壤生物学特征的影响.结果表明:YMF显著增加了根际土壤中细菌数量和微生物总量,真菌数量明显减少,但对放线菌数量影响差异不显著.YMF处理根系活力分别比NMF、DCM和CK提高了22.49%、13.25%和15.33%.PGPR生物肥料对樱桃根系生长和构建影响显著,YMF处理0～40 cm土壤剖面中根系重量尤其是毛细根重量显著增加.同NMF处理相比,YMF处理根际土壤的pH降低8.61%,阳离子代换能力显著提高.此外,YMF处理显著增加了根际土壤中养分离子的有效性,速效磷和有效钾含量分别增加17.21%和9.56%,但碱解氮含量差异不显著.因此,PGPR生物肥的施用在一定程度上改善了根际土壤的生态环境,提高了根际土壤中养分离子的有效性和养分保持能力,提高了根系活力,促进了表层土壤中(主要为0～40 cm)根系尤其是毛细根的生长.

The aim of this research was to determine the effects of plant growth-promoting rhizobacteria（PGPR） fertilizer on the biological characteristics,root activity,growth and construction of Cerasus pseudocerasus（Lindl.） G.Don（sweet cherry）.To prepare sweet cherry biological-fertilizer（YMF）,dominant bacteria YT-3,a type of PGPR,was extracted from rhizosphere soil of C.pseudocerasus trees by keeping green method and radish cotyledon weight increase method.Sweet cherry biological-fertilizer was prepared by compounding YT-3 and decomposed chicken manure（DCM）.The effects of YMF,normal biological fertilizer（NMF） and DCM on biological characteristics of C.pseudocerasus rhizosphere soil were studied in Yiyuan sweet cherry orchards.And the effects of YMF,DCM and NMF on the root activity,growth and construction of C.pseudocerasus were also investigated.The results showed that YMF increased the amount of bacteria and total microorganism amount in rhizosphere soil of C.pseudocerasus,but the fungus amount was decreased significantly.However,YMF had no influence on actinomycetes amount in rhizosphere soil.Root activity in YMF was significantly increased by 15.33%,22.49% and 13.25% than that in CK,NMF and DCM,respectively.YMF had great influence on the root growth and construction of C.pseudocerasus.Root weight,especially fine root weight in 0～40 soil profile of YMF was significantly increased.Rhizosphere soil pH value in YMF decreased by 8.61% than that in NMF.In addition,YMF significantly enhanced available phosphorus and potassium contents by 17.21% and 9.56%,respectively,compared to that in NMF.However,it had no effects on available nitrogen content in sweet cherry rhizosphere soil.Moreover,PGPR fertilizer increased the cation exchange capacity of rhizosphere soil,which benefited the nutrient retain and uptake of C.pseudocerasus.As a result,plant growth-promoting rhizobactera biological-fertilizer benefited the ecological environment of sweet cherry rhizosphere soil,improved nutrient availability and cation exchange capacity,increased the root activity and benefited the root growth,especially fine root growth in top soil（mainly 0～40 cm）.