MACROCYCLIC TRICHOTHECENES IN BACCHARIS-CORIDIFOLIA PLANTS AND ENDOPHYTES AND BACCHARIS-ARTEMISIOIDES PLANTS

Toxic disease in livestock caused by the shrubs Baccharis cor coridifo lia and Baccharis artemisioides is very common in Argentina. The toxic ity of Argentinian and Brazilian B, coridifolia plants and of Argentin ian B. artemisioides was investigated. The toxicogenic capacity of 15 endothyte isolates of Ceratopicnidium baccharidicola from B, coridifol ia was determined. Roridins and verrucarins were analyzed by thin-laye r chromatography using a modified Jarvis method. One-hundred per cent of Argentinian B. coridifolia plants were positive for roridins (RA an d RE) and verrucarins (VA and VJ), 16.2% for RD and 2.7% for RH. All o f the Brazilian B. coridifolia plants were positive only for roridins. In B. artemisioides plants, RAI RE and RD were present in higher conc entrations than VA and VJ, and all of them were more concentrated than in B. coridifolia. One-third of the endophyte isolates were toxicogen ic for the same roridins and verrucarins, but in very low concentratio ns. This is the first report of macrocyclic trichothecenes in B. artem isioides, and a new report of B. coridifolia macrocyclic trichothecene s in Argentina. (C) 1997 Elsevier Science Ltd.