Temporal And Spatial Distribution Of AM Fungi In The Rhizosphere Of Hedysarum Scoparium And Artemisia Ordosica In Northwestern China

The Hedysarum scoparium is a leguminous shrub plant endemic to the inland deserts of Asia.The flower rod has good economic value and huge ecological value,and its well-developed root system can resist lodging and better absorb soil water.It is an excellent variety for wind prevention and sand fixation in the desert region of northwest China.Artemisia ordosica is a semi-shrub plant of Compositae,which is widely distributed in northern China,mainly in arid and semi-arid areas of Shaanxi,Inner Mongolia Autonomous region,Ningxia Hui Autonomous region and Gansu,and a small amount in northern Hebei and western Shanxi.Now it has become a high-quality forage grass,medicinal plant and wind-proof and sand-fixing plant in the desert region of northern China.Arbuscular mycorrhizal fungi are a kind of small fungi belonging to Glomeromycota,which are widely distributed in soil.Understanding the community composition and distribution characteristics of arbuscular mycorrhizal fungi is an important part of ecology.The combination of optical microscope and scanning electron microscope is helpful to identify fungal spores more accurately.In this experiment,the flower stick and Artemisia annua natural distribution zone were selected from Ordos,Dengkou,Alashanzuo Banner,Wuhai,Shapotou,Ningxia,Minqin and Anxi,Inner Mongolia.Artemisia annua was selected from four typical plots in Inner Mongolia,Alashan Zuoqi,Shapotou,Ningxia and Minqin,Gansu to collect rhizosphere soil and root samples.Through the combination of scanning electron microscope and optical microscope,the community composition and species diversity of AM fungi in desert area were studied,and the correlation between soil factors and root colonization was analyzed.The purpose of this paper is to provide a basis for elucidating the ecological distribution of AM fungi and the mechanism of adapting to desert environment,and for controlling desertification.The main test results are as follows:1.A total of 38 species of 6 genera of AM fungi were isolated and isolated from the soil samples of H.scoparium and A.ordosica roots in the northwest desert,of which 36 species of 6 genera and 32 species of 6 genera of A.ordosica were identified by flower rods.12 species of Amycolatopsis spp.,2 unspecified species,accounting for 36.84%;4 species of cystic saccharomyces,accounting for 10.52%;2 species of cystic saccharomyces,accounting for 5.26%;There are 2 species,accounting for 5.26%;14 species of Glomus spp.,Accounting for 36.84%;2 species of Cystosporium spp.,Accounting for 5.26%.2.Soil factor analysis showed that the rhizosphere soil factors of H.scoparium were significantly different,and the differences were different;the total annual extraction of Globulin and the easy extraction of Globulin in the rhizosphere of A.ordosica inter-annual differences Significantly,there is no significant difference in the content of other plots between years.3.There is a significant spatial heterogeneity in the colonization rate of AM fungi: the mycelial colonization rate and colonization intensity of the H.scoparium plants showed a downward trend in 2018,and there was no significant change in the vesicle colonization rate and the total colonization rate;The colonization intensity showed a downward trend,and the mycelial colonization rate,vesicle colonization rate and total colonization rate all showed an upward trend.A.ordosica plants in 2018,the mycelial colonization rate,vesicle colonization rate,total colonization rate and colonization intensity increased first and then decreased with the elevation;in 2019,the mycelium colonization rate,vesicle colonization rate,total Colonization rate and colonization intensity showed a downward trend with increasing altitude.4.The mycelial colonization rate,vesicle colonization rate,and total colonization rate of H.scoparium were not found to be significantly correlated with soil factors;the colonization intensity was significantly negatively correlated with organic carbon and acid phosphatase.The mycelial colonization rate of A.ordosica plants was significantly negatively correlated with organic carbon,acid phosphatase and alkaline phosphatase,and significantly negatively correlated with urease and humidity.5.The analysis of the main components of AM fungi showed that: ammonium nitrogen,alkaline phosphatase,easy-to-extract globulin and humidity can reflect the rhizosphere soil conditions of H.scoparium;ammonium nitrogen,humidity,urease and available phosphorus can reflect A.ordosica Rhizosphere soil conditions.6.In the desert two plant species,by comparing the number of fungi,soil factors,and colonization rate of the two,it is concluded that H.scoparium are conducive to improving the desert environment and accelerating the restoration of vegetation.