In vitro antifungal activity of wild chayote fruit juice (Sechium compositum) on Botrytis cinerea

Sechium compositum is a wild chayote from the tropical areas of Mexico, the fruits have a high content of natural products with antiproliferative properties. In this work, the effect of chayote juice in inhibiting the growth of Botrytis cinerea under in vitro conditions was evaluated. The content of cucurbitacins, phenolic acids and flavonoids of the juice was determined. Subsequently, 10 concentrations of juice, absolute control and chemical control with cyprodinil + fludioxonil (Swicht^® Syngenta) were evaluated in potato-dextrose-agar media. The sensitivity of B. cinerea to the juice was determined based on the inhibition of mycelial growth and conidia germination. The results indicate that the juice contains 874.80 mg kg^‑1 of cucurbitacins, mainly type I; 730.82 mg kg^‑1 of phenolic compounds highlighting chlorogenic and gallic acid; and 577.82 mg kg^‑1 of flavonoids. The media with 1.0 and 5.0% of juice had growth inhibitions of 94.87 and 83.15%, respectively, while the chemical control inhibited 86%, at 4 d after inoculation. The statistical analysis showed that the treatment with 1.0% juice and the fungicide did not present statistically significant differences. In the evaluation of conidia germination, the juice had 100% of inhibition in all chayote juice concentrations. Therefore, it is important to evaluate the juice of S. compositum under in vivo conditions for the control of the disease caused by B. cinerea.