石灰岩土壤基质上构树幼苗接种丛枝菌根（AM）真菌的光合特征

就石灰岩适生植物构树(Broussonetia papyrifera)分别进行菌根真菌（简称AM真菌）摩西球囊霉(Glomus mosseae)、地表球囊霉(Glomus versiforme)、透光球囊霉(Glomus diaphanum)的单独接种、混合接种和不接种处理，幼苗生长3个月后测定其生长及光合生理指标，以期从光合水平上了解接种AM真菌对植物的生长、生理的响应。结果表明：接种AM真菌促进了构树幼苗生长，接种组地茎、苗高、总叶面积较对照差异性显著，但单株幼苗叶片数较对照无显著差异。接种处理导致了幼苗较高的菌根侵染率，而非接种处理侵染率为0。较对照而言，接种处理净光合速率显著提高,而蒸腾速率和气孔导度在单接种G.diaphanum下降低，其他三种处理均显著提高。接种处理光合耗水量较对照处理显著降低，提高了光合水分利用效率。接种后叶绿素a、b含量极显著提高。

Photosynthetic Characteristics of Broussonetia papyrifera Seedlings Inoculated AM Fungus in Limestone Soil Substratum

It’s difficult to restore vegetation in limestone area, due to the severe and thin soil layer of the limestone habitat. However, some plants adaptive to limestone soil like Broussonetia papyrifera grow in this habitat, the reason maybe that these plants possess rhizospher microbes like arbuscular mycorrhizal fungus. In this paper, an experiment was conducted on B. papyrifera seedling by disposals of single inoculation, co-inoculation and non inoculation used three mycorrhizal fungus，which are Glomus.mosseea, G. versiforme and G. diaphanum. Some photosynthesis indexes are measured to study the physiological responses in this experiment after 3 months. The results show that, the disposal of inoculated AM fungus improve the growth of host plants about height ,ground diameter, leaf area while compareing with the none. The pcolonization rate root increase by inoculation AM fungus. The net photosynthesis rate(Pn) increase significantly in each disposal inoculated AM. Transpiration rate(E) and stomatal conductance(Sc) decrease in this disposal by G. diaphanum while the others represent significant enhancement compared with non-inoculation. By inoculation, the photosynthesis-water-comsumtion decrease significantly in host plants, it indicate that the water use efficiency(WUE) improve by inoculation. The content of Chl a and Chl b increase extremely significant.