江淮地区苜蓿短期连作对后作高丹草生长及土壤微环境的影响  

Effects of short-term continuous cropping of alfalfa on the growth and soil microenvironment of subsequent sorghum-sudan grass hybrid crops in the Jianghuai area

作　　者：李争艳[1] 徐智明[1] 李岩[1] 李杨[1] LI Zheng-yan;XU Zhi-ming;LI Yan;LI Yang(The Institute of Animal Husbandry and Veterinary Medicine,Anhui Academy of Agricultural Sciences,Anhui Province Key Laboratory of Livestock and Poultry Product Safety Engineering,Hefei 230031,China)

机构地区：[1]安徽省农业科学院畜牧兽医研究所,畜禽产品安全工程安徽省重点实验室,安徽合肥230031

出　　处：《草业学报》2024年第9期155-168,共14页Acta Prataculturae Sinica

基　　金：安徽省重点研发项目(202104e110220002);新疆维吾尔自治区重点研发计划项目(2020B01008);安徽省财政农业科技成果转化项目(2022ZH009)资助。

摘　　要：为了探究苜蓿连作对后作高丹草产量品质及土壤健康状况的影响,分别以撂荒地正茬种植高丹草(yr_(0))为对照、苜蓿1年龄(yr_(1))、3年龄(yr_(3))、5年龄(yr_(5))后轮作高丹草3种处理方式为研究对象,采用传统方法,试剂盒及高通量测序方法检测了轮作后高丹草的生长状况及产量差异、轮作后土壤化学性质、酶活性及微生物结构组成的变化,阐明了苜蓿短期连作对后作高丹草生长及产量的影响,从土壤微环境的角度评价了苜蓿连作对后作高丹草的影响。研究结果显示,与正茬高丹草相比(yr_(0)),苜蓿轮作高丹草促进了后茬高丹草叶片数量及产量的增加,3年龄苜蓿(yr_(3))轮作高丹草与正茬(yr_(0))高丹草相比,后作高丹草产量增加了63.23%(P<0.05),粗蛋白及中性洗涤纤维含量也相应提高;后作高丹草土壤pH值随着前作苜蓿年龄的增加持续降低,土壤有机质、全氮含量持续增加,5年龄(yr_(5))苜蓿轮作高丹草后有机质含量比正茬高丹草(yr_(0))土壤增加了78.25%、全氮含量与正茬高丹草(yr_(0))土壤相比增加了34.88%(P<0.05);蔗糖酶活性在1年龄(yr_(1))苜蓿轮茬高丹草土壤中最高,脲酶在3年龄(yr_(3))后茬土壤中活性最高;在苜蓿轮作高丹草根际土壤中门水平优势细菌群落为变形菌、拟杆菌和厚壁菌,优势真菌群落为子囊菌、担子菌和聚合菌;前茬苜蓿3年龄(yr_(3))时轮作高丹草土壤细菌丰富度及多样性指数均为最高(P<0.05);前茬苜蓿5年龄(yr_(5))时轮作高丹草土壤真菌Shannon指数最高(P<0.05);苜蓿轮作高丹草土壤中的绿弯菌、浮霉菌、放线菌随着前作苜蓿年龄的增加呈先增加随后降低的变化趋势;相关性分析表明,土壤pH、有机质含量与土壤微生物结构关系紧密,苜蓿-高丹草轮作处理下,前作苜蓿分泌物和残体降解物进入土壤生态系统,加速特异微生物区系重构,缓解了土壤酸化及调整营养物质循环,具�This study investigated the effects of a previous alfalfa(Medicago sativa)crop on the performance of subsequent crops of sorghum-sudan grass hybrid(Sorghum bicolor×Sorghum sudanense).We utilized abandoned land as a control treatment(yr_(0)),compared with adjacent land planted in alfalfa for 1 year(yr_(1)),3 years(yr_(3)),or 5 years(yr_(5)),to determine the effect of previous length of time under alfalfa cropping on the yield,quality,and soil health of a subsequent sorghum-sudan grass hybrid crop.The research methodology combined traditional agronomy methods to measure sorghum-sudan grass hybrid crop growth,yield differences and soil chemical properties,the kit methods to measure enzyme activities and with high-throughput sequencing methods to detect changes in soil microbial community composition under the various alfalfa rotations.The results showed that,compared with yr_(0),previous planting in alfalfa improved sorghum-sudan grass hybrid crop vigor and promoted an increase in the number of leaves and yield of the following crop.The yr_(3) treatment was optimal,with an increase in yield of 63.23%(P<0.05)compared to the control(yr_(0)).The crude protein and neutral detergent fiber contents of the sorghum-sudan grass hybrid crop were also increased by previous planting in alfalfa.With increasing length of time previously planted in alfalfa,the soil pH of the subsequent sorghum-sudan grass hybrid crop decreased,the soil organic matter and total nitrogen contents increased,and soil enzyme activities were generally increased.Specifically,soil organic matter of yr_(5) sorghum-sudan grass hybrid crops was increased by 78.25%and soil total nitrogen was increased by 34.88%compared to yr_(0)(P<0.05).The soil sucrase activity of the subsequent sorghum-sudan grass hybrid was highest in the yr_(1) treatment,while the urease activity was highest in yr_(3).At the phylum level,the dominant bacterial communities in the rhizosphere soil of subsequent sorghum-sudan grass hybrid crop were Proteobacteria,Bacteroidetes,Firmicutes,an

关 键 词：苜蓿-高丹草轮作 高丹草生长 微生物群落结构 土壤环境 

分 类 号：S541[农业科学—作物学] S544.9