Gonzalo F. Gil1, Eugenio Gómez2 y Kay Ryugo3

To control excesive vegetative growth of grapes (Vitis vinifera L.), the use of the synthetic growth retardant ALAR was assessed on the variety Cabernet. Spray applicatins of ALAR at 2,000 and 4,000 ppm at 15 and 5 days prior to bloom not only reduced terminal growth but resulted in: 1) enhanced lateral shoot formation; 2) a delay of anthesis, both in the year of treatment and in the following season, and 3) a delay in ripening, because the rates of accumulation of soluble solids and diminution of acidity were delayed.
The average berry weight was reduced proportionally to the dosage, but the total yield per vine was not affected at 2,000 ppm due to fruitfulness of the induced lateral growth. However, at 4,000 ppm total yield and the average leaf area per vine were markedly reduced.

1Ing. Agr. M.S., Profesor del Departamento de Frutales y Viñas, Facultad de Agronomía, Universidad Católica de Chile, Casilla 114 D, Santiago, Chile.
2Ing. Agrónomo.
3Ph. D. Profesor de Pomologia, Universidad de California, Davis, USA.