ABSTRACT
Effect of water stress during fruit growth phase II of peach trees cv. Kakamas on yield and tree water status

Raúl Ferreyra E.1*, Gabriel Selles V.1 y Gamalier Lemus S.1
 

Water is a scarce resource in the central zone of Chile, where the greatest peach (Prunus persica L. Bastsch) growing area is found, so it is necessary to possess information that permits the efficient use of water. In the last few years, using the characteristics of the peach fruit growth, it has been possible to decrease water consumption during phase II, without affecting fruit production and quality. The experiment was carried out between 1994 and 1996 on 90 plants in an orchard of high-density peaches cv. ‘Kakamas’ with a density of 1250 plants per hectare, planted in August of 1991, at the La Platina Experimental Center (33º34 ' S lat; 70º38 ' W long). Results showed that water supplied could be reduced by 36% ETc of crop evapotranspiration without significantly affecting fruit yield and size. As well, stem water potential, measured at noon (SWPn), is a good indicator of plant water status, and can be useful as a control of water stress on peach trees, during phase II of fruit growth. Stem water potential averages measured at noon (SWPn) over –1.0 MPa did not affect fruit size, and values of around –1.5 MPa only affected them by approximately 4%. However, this practice can affect tree vigor in the medium term, since water deficit in phase II was seen to diminish trunk diameter.

Keywords: water relations, water deficit, regulated deficit irrigation.
1 Instituto de Investigaciones Agropecuarias, Centro Regional de Investigación La Platina, Casilla 439, Correo 3, Código postal 7083150, Santiago, Chile. E - mail: rferreyr@inia.cl * Autor para correspondencia.