Entrophospora etunicata: A mycorrhizal biostimulant with the potential to enhance the production of bioactive health-promoting compounds in leaves of Capsicum chinense seedlings

Abstract

Arbuscular mycorrhizal fungi (AMF) are known to benefit pepper species, but there are no reports of such efficiency in Capsicum chinense, one of the most valuable commercial plant species. Therefore, this study aimed to select an efficient mycorrhizal biostimulant to increase the production of secondary compounds and the antioxidant activity in C. chinense leaves. The experiment was conducted in a greenhouse with four mycorrhizal inoculation treatments (control without AMF, seedlings inoculated with Entrophospora etunicata, Acaulospora longula, and Gigaspora albida). After 120 days, agronomic growth parameters, production of primary and secondary metabolites, and foliar antioxidant activity were evaluated. Capsicum chinense seedlings inoculated with E. etunicata had increases in growth parameters ranging from 27 to 133% compared to the non-inoculated control, depending on the variable considered. Pepper seedlings associated with E. etunicata produced 77%, 147%, 140%, and 136% more soluble carbohydrates, total proanthocyanidins, total phenols, and total saponins, respectively, compared to those not inoculated. Such benefits were also reported for total proteins and total foliar flavonoids. On the other hand, this AMF was ineffective in enhancing the accumulation of alkaloids. It is concluded that E. etunicata is an alternative for improving the production of C. chinense seedlings and enhancing the anabolism of health-promoting bioactive compounds in the phytomass to be offered to the herbal medicine industry. This is the first report on the potential of mycorrhizal inoculation to optimize secondary anabolism in C. chinense leaves.