In situ effectiveness evaluation of two cupper synthetic chemical products in the control of sour rot in grapes

DIAZ M.; LONGONE V.; PONSONE L.; COMBINA M.; STOCCO A.F.; RODRIGUEZ ROMERA M.

Bento Gonzalves

Congreso; 39º Congresso Mundial de la Viña y el Vino; 2016

Organizacion Internacional de la Vid y el Vino (OIV)

Sour rot of grapes is caused by a complex of yeast including species as Saccharomyces cerevisiae, Pichia membranifaciens, Issatchenkia orientalis and Pichia galeiformes. In the presence of micro damages can trigger the disease; and combined with the action of acetic bacteria present in the vineyard produce the symptomatology of sour rot. So far there is no known way of controlling the disease in Argentina. The aim of this study was to evaluate the effect of two chemicals fungicides in controlling both, incidence and severity of sour rot disease in Vitis vinifera. The chemical fungicides tested were: Copper Hydroxide (300 and 400 g/hl), Copper Oxychloride (400 and 500 g/hl). The test was carried out in two cultivars: cv. Semillon and cv. Red Globe with high susceptibility to acid rot and low susceptibility to sour rot respectively. Four replicates of four treatments mentioned were performed, and a control treatment. The fungicides were applied every 15 days since veraison to 15 days before harvest. At the time of harvest visual evaluation of all treatments was made, recording the percentage of the affected cluster to estimate the percentage of severity and incidence of the disease. In the case of cv Red Globe, the incidence of sour rot was relatively low, it was observed that the chemical more effective was the copper oxychloride (500 g / hl), followed in efficiency by copper hydroxide (300g / hl) oxychloride copper (400g / hl) respectively (p