Arbuscular mycorrhiza and vermicompost alleviate drought stress and enhance yield, total flavonoid, rutin content, and antioxidant activity of buckwheat (Fagopyrum esculentum Moench)

The use of root symbionts and vermicompost as powerful natural tools is advised in stress conditions. To study the effect of vermicompost and mycorrhizal fungi on some phytochemicals and functional traits of buckwheat under drought stress, a greenhouse experiment was conducted. Three levels of drought stress: D0 (100% Field Capacity: FC), D1 (75% FC), and D2 (50% FC), two levels of mycorrhizal inoculation: M0 (without) and M1(with), and two levels of vermicompost V0 (without) and V1 (with) were used. Vermicompost significantly enhanced seed yield and aerial parts biomass. The highest grain yield (4.97 g dry weight per pot) and aerial parts biomass (40.3 g fresh weight per pot) were obtained in D0V1. The use of mycorrhiza was mainly effective on phytochemical parameters. Moderate levels of drought stress (D1: 75% FC) increased total phenols (33.6 mg gallic acid/g dry weight) and flavonoids (38.3 mg rutin/g Dry weight). Rutin content ranged from 16.24 to 32.5 mg/g dry weight that the highest content being in D1V1M0. Phenolic, flavonoid, and rutin content are correlated with higher antioxidant properties. This increase showed that mycorrhiza and vermicompost act as moderators and elicit to produce metabolites. Simultaneous use of M and V increased nitrogen, phosphorus, and potassium uptake. Cluster analysis classified the treatments into three groups with a higher impact of drought stress. According to Principal component analysis (PCA) FWH, Rutin, TFC, TPC, SS, and IC50 were affecting dimensions. The results showed that drought stress up to 75% FC (D1) can be used in buckwheat.