摘 要 :不同施肥处理影响AMF(Arbuscular mycorrhizal fungi)群体结构,然而不同AMF群体结构对植物的生长以及养分吸收的影响尚未见报道,试验利用盆栽实验研究了7种不同来源的丛枝菌根真菌(AMF)群落对白三叶草生长和N、P、K以及微量元素Cu、Zn、Mn的吸收的影响。7种AMF群落分离自长期定位施肥试验地,分别为NPK、OM、CK、1/2OM、 NP 、NK和PK。每年施肥量是300 kg N/hm2,135 kg P2O5/hm2,300 kg K2O/hm2。有机肥处理的N、P、K养分量与试验地NPK处理含量相同,原料以粉碎的麦秆为主,加上适量的大豆饼和棉仁饼,有机肥经堆制发酵后施用。试验土壤采用封丘试验地土壤,经灭菌处理。试验结果表明,接种不同AMF群落均能促进三叶草的生长,对养分吸收则表现不同。分离自CK试验地的AMF群落对三叶草侵染率显著低于其它6种AMF群落。分离自1/2OM和OM试验地的AMF群落较分离自NPK、CK、NP 和NK的AMF群落显著促进了三叶草对P的吸收;各种AMF群落都促进了对N和K的吸收;分离自OM、CK、1/2OM、 NP 、NK试验地的降低了三叶草植株N含量;分离自NPK试验地的AMF群落提高了三叶草植物K含量;对于Cu、Zn、Mn元素的吸收,不同处理存在较大的差异。AMF群落对三叶草生长以及养分吸收贡献不同,这与不同施肥管理下不同AMF群落的优势种属的侵染率、养分转化以及菌丝发育及分布有关。
Abstract:Arbuscular mycorrhizal fungi community structure is affect by different fertilization but it is unclear how this affects plant growth and nutrient uptake. We studied the effects of 7 different mycorrhizal communities on growth and N, P, K, Cu, Zn, Mn uptake of white clover in pot experiments. The 7 AMF communities were collected from a long-term fertilization field trial, with the following treatments: control without amendment (CK), nitrogen + phosphorus + potassium fertilization (NPK), organic matter fertilization (OM), nitrogen + phosphorus + potassium + organic matter fertilization (1/2OM), nitrogen + phosphorus fertilization (NP), nitrogen + potassium fertilization (NK) and phosphorus + potassium fertilization (PK). The nutrients were applied annually at the following rates N 300kg /hm2 as urea, P2O5135 kg/hm2 as Ca(H2PO4) 2, K2O 300kg/hm2 as K2SO4 with similar rates in the NPK and the OM treatment. The OM treatment consisted of mix wheat straw and fermented soybean and cottonseed, organic fertilizer. For the pot experiment, the soil from a long-term fixed fertilization in Fengqiu was sterilized. All AMF communities had a positive effect on white clover growth, but their effects differed. The AMF colonization rate of the community from the control was significant lower than all other treatments. AMF communities collected from 1/2OM and OM significantly improved P uptake. Compared to CK, most AMF communities improved uptake of N and K; Compared to the other treatments, AMF communities collected from OM, CK, 1/2OM, NP, NK reduced N concentration, and those collected from NPK increased K concentration. The concentrations of Cu, Zn, Mn differed between treatments. These results show that different AMF communities affect growth and nutrient uptake on white clover differentially, probably because of different dominant AMF species which may differ in colonization rate, nutrient transfer to the host and development of hyphae.