Effect of two kinds of arbuscular mycorrhizal fungi on plant growth and anthracnose of Vicia sativa

Common vetch (Vicia sativa), found in the alpine regions, is a legume important for its use as forage and as green manure. Anthracnose caused by Colletotrichum lentis is a new disease that severely restricts the production of common vetch. Arbuscular mycorrhizal (AM) fungi can enhance the resistance of plants to stress. In this study, a pot experiment was established in a greenhouse to study the effects of AM fungi (Glomus tortuosum and Rhizophagus intraradices) on the growth of common vetch (V. sativa ‘Lanjian No.3’) and the occurrence of anthracnose disease in it. The results showed that the incidence of anthracnose was significantly inhibited after inoculation with these AM fungi - the inhibition rate was up to 70.15%, and the disease index was down to 51.36% compared with the control. AM fungi promoted plant growth and the absorption of nitrogen and phosphorus. Compared with the control, after vaccinating with AM fungi, the shoot biomass increased by 18.44%～54.92%, and the root biomass increased by 25.68%～84.68%. The N and P content increased by up to one time compared with the control. In addition, AM fungi significantly increased the activity of peroxidase (POD) and catalase (CAT), and decreased the content of malondialdehyde of common vetch (P < 0.05). In summary, G. tortuosum and R. intraradices effectively inhibited the occurrence of anthracnose while also significantly promoting nutrient absorption and plant growth, thus changing the plant biochemical indicators. The two AM fungi have potential to be used as biocontrol agents for anthracnose of common vetch.