Effect Of AMF Inoculation On Root Absorption Strategy And Photosynthetic Characteristics Of Fraxinus Mandshurica Rupr. Seedings

In order to clarify the root absorption strategy and leaf photosynthetic characteristics of different developmental stages of Fraxinus mandshurica after inoculation AMF.,we used annual Fraxinus mandshurica as the research material,so as to know after inoculation mycorrhizal fungi(Glomus,etunicatum,Glomus mosseae,Glomus etunicatum and Glomus mosseae),the changes of root morphology,root anatomical structure,root hair development and leaf photosynthetic capacity,leaf anatomical structure.The main results were as follows:(1)After inoculation with AMF,there were differences in root grade number,root morphology and root hair morphology during seedling development,root absorption strategies also changed.At the emergence stage,compared with the control,the morphology of the main roots did not change significantly in the seedlings containing the AMF in the matrix,and only the diameter of the vascular bundles and the root hair morphology of the roots changed.At the seedling stage,the inoculation treatment and the control seedlings all had third-order root order,and there were mycorrhizal infections on the roots of the first and second grades.The root length,root surface area and root volume of grades 1 and 2 were greater than the control.Compared with the control,the number and length of grade 1 root hairs after mycorrhizal infection were significantly lower than the control.During this period,the diameter of the root vascular bundle at the 3 root order after mycorrhizal infection was greater than that of the control.In the fast-growing period,the root order of the inoculated seedlings and the control seedlings were all grade 4,and there were mycorrhizal infections on the roots of only the lt and 2 grades.Mixed AMF can improve the root length,root surface area,root volume and root tip number.AMF significantly reduced the number and length of 1 and 2 root order hairs.The diameter of 1-3 root order vascular bundles of inoculated seedlings increased significantly compared with the control.In the late growth stage,there were AMF infection on the roots of grades 1 and 2.The root order of the inoculated and the control seedlings were all grade 5.The root length,root surface area,root volume and root tip number of the inoculated seedlings were higher than the control.Inoculation significantly reduced the number and length of grade 1 root hairs.The vascular bundle diameter of the roots of the inoculated seedlings was higher than that of the control.(2)There were differences in leaf photosynthesis ability and anatomical structure of each growing stage of Fraxinus mandshurica.During the fast-growing stage,AMF could promote the photosynthetic capacity of ash obviously.After inoculation,the photosynthesis rate,transpiration rate and stomatal conductance of fast-growing stage Fraxinus mandshurica were significantly higher than no inoculation.The photosynthesis rate of Glomus mosseae,Glomus etunicatum and mixed inoculation were 33.01%,34.27%and 43.17%higher than that of the control respectly.The transpiration rate of Glomus mosseae,Glomus etunicatum and mixed inoculation were 70.29%,82.10%and 85.55%higher than that of the control respectly,the stomatal conductance Glomus mosseae,Glomus etunicatum and mixed inoculation were 77.90%?96.77%and 104.04%higher than that of the control respectly.Inoculation treatment improved the leaf thickness,the thickness of the epidermis,fence tissue thickness of the Fraxinus mandshurica.,while the sponge tissue and the porosity decreased.(3)Mycorrhizal fungal infection promoted the growth of Fraxinus mandshurica.The seedling height,leaf area and root biomass of the infected plants increased significantly by 22.37%,15.52%and 16.30%,respectively.Inoculation enhanced the correlation between the root system and leaf structure and function of ash.At the seedling stage,after the mycorrhizal infection,the positive correlation between the first root length,root surface area,root tip number(react root expansion ability)and leaf photosynthetic rate(photosynthetic capacity of the plant)became significantly positively correlated;the number of root hairs and The photosynthetic rate became a significant negative correlation.In the fast-growing period,root length,root surface area,root volume,leaf thickness,and palisade tissue thickness were basically positively correlated by a negative correlation.In the late growth stage,the negative correlation between root surface area,root volume and sponge tissue thickness became a significantly negative correlated.In summary,the inoculation of mycorrhizal fungi affected the leaf structure and enhanced the photosynthetic capacity of the leaves;the control rely on the root hairs and root extension to absorb water,while the bacterial seedlings used the mycorrhiza and root extension to absorb mainly,root hair was supplemented.