丛枝菌根真菌与磷添加对成株与幼苗间生长关系的影响

为探讨土壤磷梯度对成株与幼苗间菌根效应的影响,通过盆栽试验研究AMF和不同磷添加量对羊草(Leymus chinensis)成株和冷蒿(Artemisia frigida)幼苗间生长关系的影响。结果表明:AMF显著增加了羊草成株的生物量;冷蒿幼苗的菌根效应和菌丝的吸氮吸磷贡献率仅在P1添加水平(2 mg·kg^-1)时为正效应,其余磷水平下均为负效应。接菌降低了冷蒿幼苗生物量达到最高值时所需要的磷添加水平。研究表明羊草成株旁冷蒿幼苗的建植受到土壤磷含量的影响,当磷添加量大于2 mg·kg^-1 时,AMF的存在可能会抑制冷蒿幼苗的生长。

Effects of AM Fungi on the Growth Relationship between Adult Plant and Seedlings under Different Phosphorus Supply Levels

In order to study mycorrhizal responsiveness among adult plant and nearby seedlings udder different soil phosphorus concentrations, a pot experiment was conducted to evaluate the effects of AMF and phosphorus supplement on the growth relationship of Leymus chinensis adult plant and Artemisia frigida seedlings. The results showed that the interactive effects of AMF and phosphorus supplement significantly influenced the biomass of adult L. chinensis. Mycorrhizal response and the hyphae N and P contribution of A. frigida seedlings behaved positive effect at only P1 level, and showed negative effects at other treatments. Hyphae P contribution of A. frigida seedlings showed positive effect in a lower phosphorus level (≤2 mg·kg^-1 ). AMF reduced the phosphorus demand levels of A. frigida seedlings achieving the highest biomass . This study indicated that P addition could influence the seedling recruitment of A. frigida growing nearby L. chinensis adult plant, the seedling recruitment of A. frigida was decreased by AMF as the additive rate of phosphorus was above 2 mg·kg^-1.