土壤水分和种植密度对紫花苜蓿生物量分配的影响  

Effects of soil water and planting density on biomass allocation of alfalfa

作　　者：蒋朝 吴征江 李春阳 张振洲 武文莉 刘慧霞[1] JIANG Zhao;WU Zhengjiang;LI Chunyang;ZHANG Zhenzhou;WU Wenli;LIU Huixia(College of Life Science and Engineering,Northwest University for Nationalities,Lanzhou 730000,Gansu,China;Department of Chemistry and Life Science,Gansu Normal University for Nationalities,Hezuo 747000,Gansu,China)

机构地区：[1]西北民族大学生命科学与工程学院,甘肃兰州730000 [2]甘南民族师范学院化学与生命科学系,甘肃合作747000

出　　处：《草业科学》2024年第9期2094-2103,共10页Pratacultural Science

基　　金：国家自然科学基金项目(32160339);中央高校基本科研业务费项目(31920220135);国家民委中青年英才项目。

摘　　要：为探寻生物量分配对不同土壤水分和种植密度互作的响应规律,为生产管理中通过种植密度和土壤含水量耦合管理来调控植物生物量分配,提高水分利用效率和植物生产力,完善植物适应环境因素的机制研究,本研究以紫花苜蓿(Medicago sativa)为材料,通过盆栽试验分析了不同土壤水分85%~90%(W_(1))、75%~80%(W_(2))、60%~65%(W_(3))、35%~40%(W_(4))的土壤饱和含水量和不同种植密度10(D_(1))、15(D_(2))、20(D_(3))株·盆^(−1)对紫花苜蓿生物量分配的影响。结果表明,土壤水分显著影响紫花苜蓿的叶生物量、茎生物量、单株地上生物量、地上生物量、地下生物量、根冠比(P<0.05),随土壤水分的减少,均呈先增加后降低趋势,峰值均出现在土壤水分含量为土壤饱和含水量的75%~80%时。种植密度显著影响紫花苜蓿单株地上生物量、地下生物量和根冠比(P<0.05),随种植密度增大,单株地上生物量呈先增高后降低趋势,种植密度为15株·盆^(−1)时,地下生物量和根冠比则呈增高趋势。土壤水分和种植密度互作只显著影响了紫花苜蓿的单株地上生物量(P<0.05),在土壤水分为土壤饱和含水量的75%~80%,种植密度为15株·盆^(−1)时,紫花苜蓿单株地上生物量有最大值,为5.00 g。这一结果说明紫花苜蓿可以通过调节地上、地下生物量的分配来适应土壤水分和种植密度条件,提高其水分利用效率和产量。This study was conducted to explore the response of biomass allocation to different soil moisture and plant density interactions,regulate plant biomass allocation through coupled management of plant density and soil moisture content in production management,improve water use efficiency and plant productivity,and improve the mechanism of plant adaptation to environmental factors.This study used alfalfa(Medicago sativa)as the study material.The effects of different soil moisture content[85%~90%(W_(1)),75%~80%(W_(2)),60%~65%(W_(3)),35%~40%(W_(4))]and different plant densities[10(D_(1)),15(D_(2)),20(D_(3))plants per pot]on the biomass allocation of alfalfa were analyzed through pot experiments.The results showed that soil moisture significantly affected the leaf biomass,stem biomass,aboveground biomass per plant,aboveground biomass,underground biomass,and rootshoot ratio of alfalfa(P<0.05),with the decrease of soil moisture,all of them increased first and then decreased,and the peak value appeared when the soil moisture content was 75%~80%of the saturated water content;plant density significantly affected the aboveground biomass per plant,underground biomass,and root–shoot ratio of alfalfa(P<0.05).With increased plant density,the aboveground biomass per plant increased first and then decreased,and when the plant density was 15 plants per pot,the underground biomass and root–shoot ratio increased.The interaction between soil moisture and plant density only significantly affected the aboveground biomass per plant(P<0.05).When soil moisture was 75%~80%of the saturated soil moisture content and plant density was 15 plants per pot,the aboveground biomass per plant reached its maximum value of 5.00 g.This result indicates that alfalfa can adapt to soil moisture and plant density conditions by adjusting the distribution of aboveground and underground biomass to improve its water use efficiency and yield.

关 键 词：紫花苜蓿 水分梯度 密度梯度 地上生物量 地下生物量 

分 类 号：S541.9[农业科学—作物学]