Phosphites for the management of anthracnose in soybean pods

Abstract

The incidence of soybean anthracnose reduces yields and leads to financial losses. Among several management practices to control this disease, use of phosphites (Phi) can act by providing mineral nutrition, inducing resistance in the host and causing direct toxicity to the pathogen. The aim of this study was to investigate the effectiveness of phosphites in the management of anthracnose in soybean pods, in the transmission of the pathogen and the activities of plant defense enzymes. Soybean plants were sprayed with potassium (KPhi), manganese (MnPhi), zinc (ZnPhi), copper (CuPhi) phosphites and fungicide epoxiconazole + piraclostrobin at V4, R1 and R3 stages and inoculated with Colletotrichum truncatum isolate in the R3 stage. The anthracnose severity, the incidence of C. truncatum in soybean seeds, activities of catalase (CAT), peroxidase (POX) and superoxide dismutase (SOD) enzymes and contents of soluble lignin and total soluble phenols were evaluated. KPhi, CuPhi and MnPhi reduced the severity of anthracnose, the transmission of the C. truncatum, increased lignin content and SOD, POX and CAT enzymatic activity. Phosphites can be utilized in the management of anthracnose in soybean.