Study On The AMF Diversity And AM Improved The Drought Resistance Of Amygdalus Mongolica

In this paper, the mycorrhizal colonization of Amygdalus mongolica root which growth in the natural environment was observed to understand the mycorrhizal characteristics of the Amygdalus mongolica. The ectomycorrhizae fungi sclerotium and the arbuscular mycoohizal fungi spores were observed and indentified; The Amygdalus mongolica seedlings were inoculated arbuscular mycorrhizal fungi in the laboratory, the growth indicators, nutrient absorption and metabolize ability were detected to underatand the mechanism of mycorrhizae effected on Amygdalus mongolica surrival and growth in the extremely arid enviroments. The results showed that:(1) Morphological changes, extraradical hyphae and mantle those typical ectomycorrhizae characterstics were not found in the nutrient root of Amygdalus mongolica. And the sclerotium was not found in the rhizosphere soil. So the Amygdalus mongolica should be a non- ectomycorrhiza plants. The observation of the deyed root sample showed that Amygdalus mongolica is a typical arbuscular mycorrhizal plants. The frequency of colonization in the Wuhai plot was 97%, and Alashanzuoqi plot was 100%.(2) 11 arbuscular mycoohizal fungi species of 4 genera were isolated and identified from the rhizosphere soil of Amygdalus mongolica, among which 4 species: Acaulosopra delicate, Acaulosopra gerdemannii, Acaulosopra mellea and Acaulosopra rehmii were from Acaulosopra; Entrophospora infrequens was from Entrophospora; 5 species: Glomus aggregatum, Glomus geosporum, Glomus intraradices, Glomus lamellosum and Glomus mosseae were from Glomus; Scutellospa calospa was from Scutellospa. And there was an unknown species. The Acaulosopra rehmii and Glomus mosseae were domiant species in the identified species. The average spores density of Wuhai and Alashanzuoqi plots were 25.3/100g and 15.2/100g, respectivly.(3) Arbuscular mycorrhiza delayed the first occurence and entirely wiliting average time of Amygdalus mongolica under drought stress, and the corresponding average soil water content were significantly lower than non-inoculate treatment.(4) The water content of the plants which were inoculated the arbuscular mycoohizal fungi were lower than those without inoculation after drought stress. And the arbuscular mycorrhiza increased the water use effiency of the Amygdalus mongolica. Arbuscular mycorrhiza promoted the leaves of Amygdalus mongolica shedding to reduce the water consumption during drought stress. (5) The Amygdalus mongolica plants of which formed arbuscular mycorrhiza increased the absorption of P but no effection of N during the drought condition.(6) Arbuscular mycorrhiza reduced the MDA content and noticeably increased the SOD activity in the leaves of the Amygdalus mongolica after drought stress. Arbuscular mycorrhiza promoted the accumulation of soluble sugar in the leaves of the Amygdalus mongolica before drought stress, and soluble sugar was further accumulated during drought stress. However arbuscular mycorrhiza had no impaction on the proline metabolism of the Amygdalus mongolica.