Effect of field applications of fungicides and of SO2 as postharvest treatment, in the control of Botrytis cinerea Pers., in stored grapes, cv. Thompson Seedless

Mario Alvarez A.1, Vicente Vargas B.2

Thompson Seedles grapes, trained on a pergola system, were sprayed 2 or 4 times with Benomyl, Vinclozolin, Glycophene, Captan or Dicloran, at San Felipe, Aconcagua Valley. As subtreatments: fruits received a postharvest fumigation with SO2; a two-stage SO2 generator was added when packed; or packing was done with no additional treatment. Grapes were subsequently kept in cold storage, and B. cínerea decay was evaluated after 24, 45, and 68 days. When fruits were fumigated with SO2, no effect of the fungicides previously applied was observed on the control of Botrytis. When grapes were packed with an SO2 generator or did not receive SO2, effect of the preharvest treatments was observed for the three dates of evaluation. There was no dif ference between two or four applications of the fungicides. In general, fumigation with SO2 was more effective than the use of an SO2 generator, in the control of the decay. -

1 Estación Experimental La Platina (INIA), Casilla 5427, Santiago, Chile.
2 Blue Anchor de Chile Ltda. Huérfanos 757, Of. 312, Santiago, Chile.