Fijiensin, the first phytotoxin fromMycosphaerella fijiensis, the causative agent of Black Sigatoka disease

Abstract

Fijiensin, a novel phytotoxic metabolite, was isolated from a culture of the fungus Mycosphaerellafijiensis, the causal agent of Black Sigatoka disease of banana. Fijiensin is phytotoxic on various banana cultivars, but not toward non-host plants. The structure of fijiensin was determined by X-ray analysis.

An epigenetic modifier induces production of (10′ S )-verruculide B, an inhibitor of protein tyrosine phosphatases by Phoma sp. nov. LG0217, a fungal endophyte of Parkinsonia microphylla

“…2). Vermistatin ( 2 ) has been reported to act as an elastase inhibitor, 15 phytotoxin on various banana cultivars, 16 RNA synthesis inhibitor in Ehrlich ascites carcinoma, 17 P-388 leukemia, 17 weakly cytotoxic to KB tumor cell lines, 18 and an inhibitor of α -glucosidase. 19 Reported biological activities of nafuredin ( 5 ) include selective inhibition of helminth complex I and inhibition of NADH-fumarate reductase (NFRD) of Ascaris suum (pig roundworm) at nM concentrations.…”

Physiological effects of the hydrophilic phytotoxins produced by Mycosphaerella fijiensis, the causal agent of black sigatoka in banana plants

“…The symptoms of the disease include elongated, necrotic lesions surrounded by chlorotic zones, suggesting the involvement of phytotoxins (Upadhyay et al 1990). Mycosphaerella fijiensis is known to produce lipophilic phytotoxins (Hoss et al 2000;Stierle et al 1991;Upadhyay et al 1990); 2,4,8-trihydroxytetralone is the most abundant and the most phytotoxic, with a hostselectivity similar to that of the pathogen (Stierle et al 1991).…”

“…The symptoms of the disease include elongated, necrotic lesions surrounded by chlorotic zones, suggesting the involvement of phytotoxins (Upadhyay et al 1990). Mycosphaerella fijiensis is known to produce lipophilic phytotoxins (Hoss et al 2000;Stierle et al 1991;Upadhyay et al 1990); 2,4,8-trihydroxytetralone is the most abundant and the most phytotoxic, with a hostselectivity similar to that of the pathogen (Stierle et al 1991). The mechanism of action of the different lipophilic phytotoxins produced by M. fijiensis has been studied very little; however, it has been reported that their activity is light-dependent, they affect the chloroplast, and disturb the proton electrochemical gradient across the plasma membrane, increase electrolyte leakage, and induce an oxidative burst in Musa spp.…”

Production of hydrophilic phytotoxins by Mycosphaerella fijiensis

“…Even though a number of lipophilic phytotoxins have been reported from organic extracts of M. fijiensis (Hoss et al 2000;Stierle et al 1991;Upadhyay et al 1990), to date no hydrophilic phytotoxins have been identified from this pathogen. Recently, phytotoxic activity was detected, using the leaf-spot assay on banana leaves, in both the organic extract and the aqueous residual phase obtained after the ethylacetate extraction of culture filtrates of M. fijiensis grown in V-8 juice medium.…”

“…The disease significantly decreases banana production by premature ripening of the fruits and lower photosynthetic activity from a reduction in leaf area (Sanchez and Cárdenas 2002). The symptoms of the disease include elongated, necrotic lesions surrounded by chlorotic zones, suggesting the involvement of phytotoxins (Upadhyay et al 1990). …”