氮、磷供给水平对丛枝菌根真菌生长发育的影响

Influence of nitrogen and phosphorus supplying levels on development of arbuscular mycorrhizal fungi

为了研究营养元素氮、磷对丛枝菌根真菌(Arbuscular mycorrhizal fungus)生长发育的影响,以黄瓜、番茄为宿主植物,采用半液培的方式,在LAN营养液的基础上,设置不同氮、磷供给水平的处理。结果显示,同一N、P处理水平条件下,接种处理对黄瓜植株地上部和根系的生物量未产生显著影响。不同N、P供应水平对菌根生长发育影响显著。提高供氮水平显著增加了菌根结构的数量,同时降低了植株地上部的磷含量;而磷处理对侵染结构的影响因不同供氮水平而有所差异,供N 0.3 mmol/L时,提高磷供给水平显著降低了侵染结构的数量,而当把供氮水平提高到N 3 mmol/L时,随着供磷水平的增加,菌根侵染结构数量显著增加。在此条件下,基于氮对菌根真菌和植株磷营养状况的影响的一致性,氮对菌根结构的作用可能源于氮、磷之间的交互作用。

To investigate the effects of the different nitrogen and phosphorus supplying levels on development of arbuseular mycorrhizal fungi （AMF）, a pot experiment was conducted with cucumber （ Cucumis sativus ） and tomato （Lycopersicon esculenturn） as the host plants, and the semi-hydroponic system was used to cultivate the crops with different N, P concentrations based on LAN solution. The results show that there are not any significant differences of biomass between myeorrhizal and non-mycorrhizal cucumber under the same N and P treatments. AMF development is significantly affected by the N and P treatments. The more the nitrogen application, the more the AMF structure, the lower the shoot phosphorus concentration for the two plants. The influences of phosphorus application vary with the nitrogen application rates, when N content in the nutrient solution is about O. 3 mmol/L, AMF structure is decreased with the increase of P content, while when N contents in the solution are larger than 3 mmol/L, AMF structure is increased with the increase of P content. It is presumed that the effects of nitrogen on AMF structure are not direct and may be derived from interaction of nitrogen and phosphorus based on which effect on AMF structure and phosphorus nutrient status.