Effects Of Arbuscular Mycorrhizal Fungi On Growth Promotion And Salt Tolerance Improvement Of Chrysanthemum

Soil salinization is a common and serious environmental problem in the world,which has inhibited the survival,development and yield of plants.Arbuscular mycorrhizal fungi(AMF)was considered as good ameliorators.Studies on the interaction between mycorrhiza and plants to improve stress resistance are mainly carried out in legumes,wheat,maize and poplar at present,while related researches on horticultural plants are few.In terms of salt tolerance,the research mainly focused on the molecular and physiological mechanisms of salt tolerance of chrysanthemum,and how to improve the salt tolerance through mycorrhiza for better promotion and application is the core of this study.The purpose of this study was to answer following questions: 1.how the symbiosis between mycorrhizal and chrysanthemum and the observation of the whole process of infection;2.if arbuscular mycorrhizal fungi can promote the growth of chrysanthemums;3.the main improved physiological mechanisms of the salt tolerance when chrysanthemum were inoculated by arbuscular mycorrhizal fungi.The main research conclusions were as follows:(1)There was a good symbiotic effect between Funneliformis mosseae and Sorghum bicolor L.Mycorrhizal infection rate could reach 94.88%,and the sporulation amount of propagated inoculum was150-200 spores per 100 g.S.bicolor L was the suitable host plant and propagated material for F.mosseae.(2)Arbuscular mycorrhizal fungi could successfully and rapidly infect the root of Chrysanthemum and formed a good symbiotic relationship.At the beginning,the infection rate was very slow,and then the infection rate increased rapidly,at the end,the infection rate slowed down.On the whole,the infection process of arbuscular mycorrhizal fungi was consistent with the characteristics of "S" curve.(3)The infection effect of different varieties of chrysanthemum was different,as for the infection rate,’Jing Lin Liu Yan’ > ’Jing Lin Fi Wu ’> ’Jing Lin You Fen’ > C.aromaticum > ’Jing Lin Xiang Qi ’>Crossostephium chinense L.> C.lavandulifolium.The growth index and biomass of chrysanthemum were significantly increased after inoculation with arbuscular mycorrhizal fungi,and the growth rate of the aboveground part was higher than that of the underground part.(4)Under salt stress,arbuscular mycorrhizal fungi could significantly promote the growth of chrysanthemum,mainly by increasing the biomass of the shoot and decreasing the root-shoot ratio(’Jing Lin Fei Wu ’had the most obvious effect,the biomass of inoculated chrysanthemum decreased by15.24% compared with uninoculated chrysanthemum).(5)Arbuscular mycorrhizal fungi improved the osmotic regulation ability under salt stress according to increase the contents of proline and soluble protein in leaves and roots of chrysanthemums.The proline content in aboveground part was significantly higher than that in underground part;Arbuscular mycorrhizal fungi improved the photosynthetic capacity of chrysanthemum under salt stress according to increasing the photosynthetic pigment content and photosynthetic index.The chlorophyll content of ’Jing Lin Fei Wu’ with changed greatly,while the chlorophyll content of ’Jing Lin Liu Yan’did not change significantly;Arbuscular mycorrhizal fungi improved antioxidant capacity of chrysanthemum according to increasing the activities of SOD and POD and reducing malondialdehyde and relative electrolyte leakagein rate in leaves and roots of chrysanthemum.This study aimed to explore the growth promotion effect and salt tolerance promotion effect of arbuscular mycorrhizal fungi on chrysanthemum,to enrich and develop relevant theoretical knowledge,and to provide theoretical basis for cultivation of chrysanthemum in saline-alkali land.