野生草地早熟禾根茎扩展对水分调控的响应  

Response of rhizome expansibility of wild Kentucky bluegrass to variations in soil water content

作　　者：张浩玮[1] 白小明[1] 樊敬辉 李雄亮 连亚红 孙敏 ZHANG Haowei;BAI Xiaoming;FAN Jinghui;LI Xiongliang;LIAN Yahong;SUN Min(College of Pratacultural Science,Gansu Agricultural University,Key Laboratory of Grassland Ecosystem, Ministry of Education,Pratacultural Engineering Laboratory of Gansu Province,Sino-U.S.Centers for Grazingland Ecosystem Sustainability,Lanzhou 730070,Gansu,China)

机构地区：[1]甘肃农业大学草业学院草业生态系统教育部重点实验室甘肃省草业工程实验室中-美草地畜牧业可持续发展研究中心,甘肃兰州730070

出　　处：《草业科学》2018年第10期2471-2480,共10页Pratacultural Science

基　　金：国家自然科学基金(31560667);甘肃农业大学校级自列课题(GSAU-ZL-2015-054)

摘　　要：在盆栽条件下,采用单株种植,以2个扩展能力强弱不同的野生草地早熟禾(Poa pratensis)‘榆中’(强)和野生草地早熟禾‘天祝’(弱)为试验材料,设4个水分处理水平[W1:90%~75%WHC(water holding capacity),W2:75%~60%WHC,W3:60%~45%WHC,W4:45%~30%WHC]研究水分调控对草地早熟禾根茎扩展的影响。结果表明,随土壤含水量降低,两个野生草地早熟禾的蒸散量、覆盖面积、分蘖数和地上生物量逐渐减小;根茎数量、茎节长、最长根茎长度、地下生物量、根茎直径、根茎表面积、根茎体积和根冠比先增大后减小,75%~60%WHC处理最大。90%~75%WHC是促进野生草地早熟禾地上扩展的最优水分处理,75%~60%WHC是促进野生草地早熟禾地下根茎扩展的最优水分处理,根茎扩展能力强的草地早熟禾‘榆中’较根茎扩展能力弱的草地早熟禾‘天祝’有较高的水分需求。A pot experiment was conducted with two wild Kentucky bluegrass(Poa pratensis)varieties to investigate their rhizome expansibility under different soil water content.The two varieties used were Yuzhong and Tianzhu,which have high and low rhizome expansibilities,respectively.Four soil water content were used:90%~75%water holding capacity(WHC),75%~60%WHC,60%~45%WHC,and 45%~30%WHC.One plant was kept in each pot.The evapotranspiration rate,coverage area,tiller numbers,and shoot biomass of both varieties decreased as soil water content decreased,while rhizome number,stem internode length,maximum rhizome length,and the underground biomass,diameter,surface area,and volume of rhizomes and root/shoot ratio of the plant increased first and then decreased as soil water content decreased,reaching their respective maximum at 75%~60%WHC.At the soil water content of 90%~75%WHC,shoot expansibility reached its maximum,while at 75%~60%WHC,rhizome expansibility reached its maximum.The Yuzhong variety,which has a higher rhizome expansibility than the Tianzhu variety,needs higher soil water content than the Tianzhu variety.

关 键 词：草地早熟禾 水分调控 根茎 覆盖面积 分蘖 生物量 根冠比 

分 类 号：S816[农业科学—饲料科学] S543.901[农业科学—畜牧学]