Nuove conoscenze sul ciclo biologico di Stemphylium vesicarium e possibilità di contenimento della maculatura bruna del pero

Recent works showed that <i>Stemphylium vesicarium</i>, the causal agent of brown spot of pear, is able to colonize the herb plants of the lawn covering the orchard soil in a permanent manner. The fungus growths on the dead leaves of these plants as saprophyte and produces conidia from spring to autumn, and pseudothecia and ascospores of <i>Pleospora allii</i> from autumn to spring, more abundantly than on the pear leaf litter. Considering that <i>S. vesicarium</i> does not produce spores on the affected pear tissue, the orchard floor (pear leaf residues and dead herb plants) is then the inoculum source for both ascospores and conidia all season long. Recent works have then evaluated the possibility of reducing disease incidence by sanitation. The application of <i>Trichoderma</i>-based products on the orchard floor significantly reduces production of both ascospores and conidia as well as disease incidence on pear fruit. Use of <i>Trichoderma</i> opens new perspectives for controlling brown spot of pear, in addition to fungicide sprays to increase their efficacy when the disease pressure is high and in organic farming.