HEC 5725 - chemodynamic behaviour of a new leaf systemic strobilurin fungicide

HEC 5725 is a novel leaf systemic fungicide of the chemical class of strobilurines, It shows a broad spectrum of disease control with high efficacy against diseases when used as a foliar fungicide, e.g. against stem base disease complex, Septoria, Mildew, Fusarium, Net blotch and Rhynchosporium. Studies to investigate the uptake and distribution within the plant have shown that HEC 5725 is a leaf systemic compound. Most of the compound is absorped by the wax-layer of the leaf and therefore remains available as a depot of fungicidally active substance. The localisation of the fungicide on and within the leaf is shown after spray application. HEC 5725 shows very good rain-stability. Artificial rain applied three hours after spray application leads to hardly any decline in efficacy against various plant pathogens. After seed treatment HEC 5725 shows a weak systemicity in acropetal direction. The biological mode of action is the inhibitory effect on fungal spore germination and on other early stages in the development of the pathogens e.g. germtube growth and penetration into the leaf as well as mycelial growth.