Abstract: In order to provide the scientific guidance for the turf fertilization in the northwestern China,the effects of N,P,and K fertilizers on the individual plant expansibility and root characteristics of tall fescue(Festuca arundinacea Schreb.) were studied through orthogonal field experiment with 3 factors and 3 levels.The results show that N was the main factor affecting the aboveground expansion of tall fescue.The plant height,coverage area,and aboveground biomass increased along with the increasing of N application amount and the number of tiller increased at the early stage and then decreased with the highest tiller number obtained at 10 gN·m^-2.P was the main factor affecting underground expansion.The root length,underground biomass,root superficial area,and root volume increased along with the increased P application amount and the root expansion range increased at early stage and then decreased with the highest root expansion range obtained at 10 gP₂O₅·m^-2.The effect ordering of 3 fertilizers on aboveground,underground and integrated expansibility of tall fescue was N>K>P,P>N>K,and N>P>K,respectively.The combination treatment of N₁₅P₁₅K₈(15 gN·m^-2,15 gP₂O₅·m^-2,and 8 gK₂O·m^-2) was the best for aboveground expansibility.The best treatment for underground expansibility was N₅P₁₅K₁₂(5 gN·m^-2,15 gP₂O₅·m^-2,and 12 gK₂O·m^-2).And for the comprehensive expansibility,the best treatment was N15P10K4(15 gN·m^-2,10 gP₂O₅·m^-2,and 4 gK₂O·m^-2).

Key words: Nitrogen, Phosphorus, Potassium, Tall fescue, Expansibility, Root characteristics

摘要： 通过3因素3水平田间正交试验,研究了氮(N)、磷(P)、钾(K)肥对高羊茅(Festuca arundinacea Schreb.)单株扩展性和根系特性的影响,以期为西北地区高羊茅草坪合理施肥提供依据。结果表明:N肥是影响高羊茅地上扩展的主要因素,N肥施量越大,植株越高,覆盖面积和地上植物量越大,分蘖随N肥施量的增加呈先增大后减小的趋势,10 g/m²N肥高羊茅的分蘖数最多;P肥是影响高羊茅地下扩展的主要因素,P肥施量越大,根系越深,地下植物量、根系表面积和根系体积越大,根系扩展幅度随P肥施量的增加呈先增大后减小的趋势,10 g/m²P肥高羊茅的根系扩展幅度最大,3种肥料对地上、地下和综合扩展性的影响大小顺序分别为N>K>P、P>N>K和N>P>K;处理组合N₁₅P₁₅K₈,即15 g/m²N肥15 g/m²P肥、8 g/m²K肥是促进高羊茅地上扩展的最佳施肥组合,处理组合N₅P₁₅K₁₂,即5 g/m²N肥15 g/m²P肥12 g/m²K肥是促进高羊茅地下扩展的最佳施肥组合,处理组合N15P10K4,即15 g/m²N肥10 g/m²P肥4 g/m²K肥是促进高羊茅综合扩展的最佳施肥组合。

关键词: 氮, 磷, 钾, 高羊茅, 扩展性, 根系特性