Dual effects of entomopathogenic fungi on control of the pest Lobesia botrana and the pathogenic fungus Eutypella microtheca on grapevine

BACKGROUND: Entomopathogenic fungi (EPF) are the natural enemies of insect pests. Nevertheless, research on the use of EPF for simultaneous prevention of pest and disease agents on the same crop is limited. In this study, we explored the potential dual effects of three strains of the EPF Metarhizium anisopliae on the control of detrimental agents of Vitis vinifera L., including different developmental stages (larvae, pupae, and adult) of the insect pest Lobesia botrana and the phytopathogenic fungus Eutypella microtheca. METHODS: Laboratory pathogenicity trials were performed to examine the effects of the three M. anisopliae strains on the mortality rate of L. botrana. In addition, field trials were conducted to assess the biocontrol potential of one selected M. anisopliae strain on the larval stage of L. botrana. Moreover, inhibitory effects of the three EPF strains on E. microtheca growth were examined in vitro. RESULTS: All the M. anisopliae strains were highly effective, killing all stages of L. botrana as well as inhibiting the growth of E. microtheca. The in vitro mortality of larvae treated with the strains was over 75%, whereas that of treated pupae and adults was over 85%. The three EPF strains showed similar efficacy against larvae and adult stages; never-theless, pupal mortality was observed to be strain dependent. Mortality of L. botrana larvae ranged from 64 to 91% at field conditions. Inhibition of E. microtheca growth reached 50% in comparison to the control. CONCLUSIONS: Our study showed that M. anisopliae strains were highly effective in ensuring control of two different detrimental agents of V. vinifera L., providing new evidence to support the dual effects of entomopathogenic fungi.

Uses of hazardous medicinal plants: composition of the essential oil of Clinopodium gilliesii (Benth. ) Kuntze (Lamiaceae), collected in Chile / Uso de plantas medicinales peligrosas: composición del aceite esencial de Clinopodium gilliesii (Benth. ) Kuntze (Lamiaceae), recolectada en Chile

Clinopodium gilliesii (Benth.) Kuntze, harvested in the Chilean highlands, contains a surprising 93.87% of the toxic monoterpene pulegone in the essential oil. These results show remarkable differences with studies of the same species carried out in Argentina and Peru. These dissimilarities in the monoterpene composition of essential oils should be associated with differences in toxicity and biological activity of this medicinal plant used in ethnomedicine in different countries for the treatment of similar discomforts and diseases. These results are discussed considering the risk of consuming C. gilliesii, without clear recommendations and control of at least pulegone content in essential oils.

Clinopodium gilliesii (Benth.) Kuntze, recolectada en el altiplano chileno, contiene un sorprendente 93,87% del monoterpeno toxico pulegona, en el aceite esencial. Estos resultados muestran diferencias notables con estudios de la misma especie realizados en Argentina y Perú. Estas disimilitudes, en la composición de los aceites esenciales deben estar asociadas con diferencias en la toxicidad y actividad biológica de esta especie medicinal que se utiliza en etnomedicina en diferentes lugares para el tratamiento de molestias y enfermedades similares. Estos resultados se discuten considerando el riesgo de consumir C. gilliesii, sin recomendaciones claras y control de al menos el contenido de pulegona en los aceites esenciales.