不同磷肥用量对高羊茅生长及养分吸收的影响

在武汉地区研究了不同磷肥用量对冷季型草坪草高羊茅Festuca arundinaces生长状况、草屑积累量、氮(N)磷(P)钾(K)养分含量及积累量的影响.结果表明:在施用N、K肥(N 15g/m2,K2O 12g/m2)基础上,P肥能明显促进草坪草分蘖并提高成坪后叶绿素含量,施P(P2O5)2.5～20.0g/m2处理的分蘖数是不施P对照的2.81～4.32倍,叶片SPAD值比对照高15.8～18.2.草屑积累量和高羊茅总干物量随P肥用量的增加而增加;施P 10.0g/m2范围内,地下部干物质量也随施P增加而增加,继续提高P用量有下降的趋势.高羊茅舍N量因施P而明显下降,地上部P、K含量随P肥用量增加而显著提高,而地下部P、K含量各处理差异不显著.P肥用量10.0g/m2时高羊茅N积累量达到最高值(7.51g/m2),是对熙的2.71倍;随着P用量的增加P、K养分积累量持续上升,且P积累量与P用量呈显著正相关.综合考虑草坪生长质量及肥料利用效率,认为在试验地力条件下新植高羊茅的P肥(P2O5)用量以5～10g/m2范围为宜.

Effects of P fertilization rates on growth and nutrients absorption in tall fescue

An experiment was conducted in Central China Wuhan region to evaluate the effect of different phosphorous fertilization rates(P2O5,0,2.5,5.0,10.0,20.0 g/m2) on growth,clipping biomass,nutrient contents,and accumulation in tall fescue.The results indicated that based on N(N,15 g/m2) and K(K2O,12 g/m2) application,P treatment promoted tillering ability and increased tiller by 2.81-4.32 times,increased leaf Chlorophyll content by 15.8-18.2 times as indicated by SPAD value.Leaf clippings and plant biomass improved significantly with the increasing of P fertilization rates,while roots biomass decreased with P application rate over 10.0 g/m2.N content in plant decreased significantly with P application,P and K content of the above ground increased with the increasing P application rate,while no significant difference was observed for under ground.Plant N accumulation achieved its peak(N,7.51 g/m2) at the rate of 10.0 g/m2,2.71 times of the control.P and K accumulation improved as the increasing P application rates,and P accumulation positively correlated to P fertilizer rate.Considering turf quality and fertilizer use efficiency,it was recommend that the appropriate P application rate for newly established tall fescue was 5-10 g/m2.