Abstract: Effects of biofertilizer on growth of the common grasses Agropyron cristatum,Medicago sativa,Stipa capillata in Lanzhou landscapes were tested under soil moisture content of 20%,40% and 60% water holding capacities(WHC).Seed germination experiments show that biofertilizer promoted the germination of the three grasses significantly(P<0.05).Potted experiments show that biofertilizer enhanced height,tiller number,biomass and root length of all three plant species.Among them,biofertilizer significantly(P<0.05) enhanced height,biomass and root length of Stipa capillata under 20,40% and 60% WHC;and tiller number under 40% WHC as well.It also significantly enhanced height,biomass and root length of Agropyron cristatum under all three soil moisture contents(P<0.05),and tiller number under 20% and 40% WHC.It also promoted height,branch number,biomass and root length of Medicago sativa significantly(P<0.05).The interaction between biofertilizer and soil moisture content shows that the effect of moisture content on growth of legume M.sativa is more obvious than biofertilizer,whereas the effect of biofertilizer is more obvious than soil moisture content on the two grasses of A.cristatum and S.capillata.

Key words: Agropyron cristatum, Medicago sativa, Stipa capillata, Soil moisture content, Plant height, Tiller, Root length, Biomass

摘要： 以兰州市常用的护坡绿化草种扁穗冰草(Agropyron cristatum)、针茅(Stipa capillata)和紫花苜蓿(Medica-go sativa)为供试材料,测定了在20%,40%和60%最大饱和持水量(WHC)的土壤湿度条件下微生物菌肥对其株高、分蘖、根长和生物量的影响,旨在为微生物菌肥在绿化护坡中提高绿化固坡效果的稳定性和持续性及其推广应用提供理论依据。结果表明:种子发芽试验中,微生物菌肥对3种草的种子发芽率有显著的促进作用(P<0.05);盆栽试验中,微生物菌肥在3种不同土壤湿度条件下对3种草均有不同程度地促进作用。其中:在3种土壤湿度条件下,对针茅的株高、生物量和根长均有显著的促进作用(P<0.05),而只有在40%WHC条件下,对其分蘖才有显著的促进作用(P<0.05);对扁穗冰草除在60%WHC下分蘖无显著差异外,其余土壤湿度条件下对其株高、分蘖、根长和生物量均有显著的促进作用(P<0.05);而对紫花苜蓿在3种不同土壤湿度条件下的4个生长指标均有显著的促进作用(P<0.05)。土壤微生物菌肥与水分互作效应中,水分在豆科牧草紫花苜蓿生长中的作用要大于微生物菌肥,而微生物菌肥在扁穗冰草和针茅2种禾草生长中的作用大于水分。

关键词: 扁穗冰草, 针茅, 紫花苜蓿, 土壤湿度, 株高, 分蘖, 根长, 生物量