Physiological Effects of Antifungals on Beans Infected with Rust

Rust (Uromyces appendiculatus) is a major foliar disease that reduces yields and pod quality in beans. The antifungal activities against U. appendiculatus by the crude extracts of selected plants were studied in vitro and in vivo experiments. In vitro evaluations was performed on extracts from Maesa lanceolata, Tithonia rotundifolia, Aloe secundiflora, Carisa edulis, Urtica dioica, Boscia angustifolia, Zanthoxylum chalybeum, Melea volkensii and Kocide DF as treatments. Single plant extracts and combinations of Boscia angustifolia, Zanthoxylum chalybeum and Melea volkensii were used to evaluate their effect on U. appendiculatus in the field. Major carotenoids from the pods of French beans were isolated and profiled using High Performance Liquid Chromatography (HPLC) peaks to determine the consistency of the compounds in the pods. Physiological responses such as carbon dioxide assimilation, Photosynthetic active radiation (PAR), Transpiration, Stomatal conductance (gs), leaf temperature and Photosynthetic rate (Pn) of French beans treatments were examined using Infrared gas analyzer (IRGA) in all treatments.