Gamalier Lemus S.1 y Jorge Retamales A.2
Observations and results of trials with ethephon in walnuts, carried out during two years in Los Andes, Chile, are presented. Ethephon, at 500 ppm, was applied in the 1977-78 growing season when, the packing-tissue was dark brown and 0, 300, 400 and 500 ppm in 1978-79, at 3 stages of fruit development; packing-tissue dark brown, 7-10 days later, and béginning of hull spli tting. Ethephon noticeably hastened nuts hull split. The better dosis lo our trials fluctuated between 300 and 400 ppm. The precise dosis will depend of the phytotoxic effects, occurring in leaves after treatment Percentage of hull splitting was not different when ethephon was applied between packirig-tiswe brow ning and beginning of huil split. However, the best moment would be the first of these stages, because phytotoxic effects were less severe and harvest was equally hastened.
1 Ing. Agr., Programa Frutales y Viñas, Estación Experimental La Platina, Instituto de Investigaciones Agropecuarias (lNlA), Casilla 5427, Santiago, Chile.
2 Ing. Agr., Pedro Mira 884, Santiago-13, Chile.