丛枝菌根真菌对小麦生长的影响

为了促进经济作物小麦的生长,提高土壤氮磷循环与转化效率,选择两种优良丛枝菌根真菌(Arbuscular mycorrhizal fungi,AMF)——摩西球囊霉(GM,Glomus mosseae)、根内球囊霉(GI,Glomus intraradices),研究AMF在小麦整个营养生长阶段中对其生长以及对土壤中植物生长需求的大量元素——氮、磷的作用及影响。结果表明:人工施加菌剂可显著提高AMF对小麦的侵染率,施加GM菌剂时,小麦侵染率提高24.54%,同时,株高提高14.08%,小麦地上生物量提高24.05%。GM效果优于GI。施加菌剂后,小麦侵染率与土壤中水解性氮呈显著正相关;植物地上生物量与土壤中总氮,水解性氮呈显著负相关。表明AMF可活化土壤中的氮元素,同时促进作物生长,强化对土壤中氮元素的利用。

Effects of Arbuscular mycorrhizal fungi (AMF) on the growth of wheat

Arbuscular mycorrhizal fungi (AMF) is one of the most widely spread micro-organisms, which could form symbiotic associations with most of the vascular plants in natural or artificial ecosystems. Previous reports revealed that AMF could promote the growth of plant by improving the utilization rate of nutrients of plants. Therefore AMF is receiving more and more attention from domestic and overseas researchers. As a new microbial fertilizer, AMF is expected to play an important role in the reduction of chemical fertilizer and be further used in controlling the pollution in natural water bodies. Wheat is one of the most important economic crops, especially in China, which is the major food crop only behind rice. Therefore, the efforts to maximize the production of wheat by applying the minimum chemical fertilizer have dual significances both in economy and ecology. In this research, we selected two species of native AMF in the field as inocula, GM (Glomus mosseae) and GI (Glomus intraradices). By investigating the status of wheat in different growth periods, we study the effects of AMF on the ultilization rate of nitrogen and phosphorus of wheat and the final effects on the production. The results indicated that the roots of wheat could be infected by AMF in natural field ecosystem, In addition, the artificial application of AMF could significantly improve the infection rate of AMF on wheat. The infection rate could be increased by 24.54% by inoculating GM and 21.93% by GI. Moreover, the height of wheat and the aboveground biomass were increased through inoculating GM by 14.08% and 23.5%, respectively; the height of wheat and aboveground biomass was increased through inoculating GI by 13.57% and 21.7%, respectively. The results also indicated that the plant height and biomass changes comply with logistic curve. According to the curve, we found that AMF could promote plants'' growth, particularly on roots. Specifically, the effect of GM was more effective than GI in the present research. The content of phosphorus in soil reached the peak level on the 120th day. The variable quantity of phosphorus in soil without the infliction of AMF is 6.35 mg/kg, and the absorptive amount could be increased by inoculating GM and GI to 11.55 mg/kg and 10.41 mg/kg, respectively. In addition, the content of hydrolytic nitrogen in soil reached the peak level during 120-150 days. However, the variable quantity had been decreased by 16.96 mg/kg by inoculating GM, at the same time, decreased by 14.67 by inoculating GI. Furthermore, there was a significantly positive correlation between the AMF infection rate and the content of hydrolytic nitrogen in the soil. And the aboveground plant biomass was negatively correlated with the content of total nitrogen and hydrolytic nitrogen in the soil. The results demonstrated that AMF could activate the nitrogen in the soil and improve the growth of wheat, benefitting the utilization of nitrogen.