Study on the Relationship between Secondary Metabolites and Resistance to Anthracnose in Stylosanthes

Stylosanthes is an excellent tropical leguminous forage. Anthracnose caused by Colletotrichum gloeosporioides is a major limiting factor in Stylosanthes production, which can lead to reduced forage and seed production and decreased quality. How to quickly screen resistant parents and varieties of Stylosanthes that are resistant to anthracnose has become an urgent problem to be solved in production. In this study, the high-performance liquid chromatography detection technology was established for simultaneous analysis of the content of salicylic acid, triethyl orthobenzoate, indazole, and soyasapogenol B in Stylosanthes leaves. The technology was further applied in the analysis of the relationship between secondary metabolites and resistance to anthracnose in 105 accessions of Stylosanthes. The result shows that salicylic acid is the most important factor for resistance to anthracnose. By detecting the content of salicylic acid in Stylosanthes leaves, a rapid screening technology for anthracnose-resistant parents and varieties of Stylosanthes was established, and 5 accessions of Stylosanthes with high resistance to anthracnose were screened. This study is of great significance to the Stylosanthes germplasm preservation and identification and its breeding.