Safety evaluation of the use of one- and two-component fungicides to protect grapes

Abstract

Viticulture and winemaking are traditional industry of agriculture in the southern regions of the Russian Federation, which playing an important role in their economy. A rich and undamaged crop is almost impossible to grow without plant protection measures. Preparations used to spray plants are by no means harmless, and do not always completely disintegrate before harvesting. The objective of the work was to study the dynamics of degradation of fungicides of systemic action, belonging to different classes, in grapes. The two-component preparation was a combination of 120 g/l difenoconazole + 60 g/l tetraconazole (MEC). The one-component preparation contained 250 g/l of cyprodinil (EC). The work was done in the Krasnodar region for 2 years. The half-lives of difenoconazole and tetraconazole were about 5 days, cyprodinil 2.7 and 4 days, 1 and 2 years, respectively. The concentration of difenoconazole and tetraconazole went down to below the MRL in the first year of the study, two weeks after the last spraying, and in the second – after three weeks, which was most likely caused by the prevailing weather conditions – “dangerous phenomenon – intense heat”. At the time of harvest, no residual amounts of difenoconazole, tetraconazole and cyprodinil were found, which indicates the safety of the products obtained for consumers.