[Effect of different volumes and irrigation frequency on raspberry plants (cv. Heritage) during the first planting year]

At the "Santa Rosa" Experiment Station of the Universidad Austral de Chile in Valdivia, Chile, during the 1990-1991 growing season, a trial was carried out to determine the effect of different irrigation volumes and frequencies on vegetative growth and fruit production of raspberry (cv. Heritage) in this first planting year. The experimental design used was a completely randomized experiment with a factorial arrangement: treatments were two irrigation frequencies (daily and weekly) and water volumes as function of potential evapotranspiration (20, 40, 60 and 80% water reposition in function of tray evaporation). The essay is composed of 8 rows with 17 plants each. Vegetative development (shoot length, number of shoot and dry matter), and reproductive development (fruit buds, number of fruits, fruit diameter, and yield) were observed. Statistical analyses were: variance analysis, mean test according to Newman Keules Student (5% significance), and variation coefficient. From the study it is concluded that irrigations with a daily frequency have significant effects on the vegetative development parameters, but not so on the reproductive development parameters. Volumes of 40% water reposition have significant effects on the parameters number and length of buds, compared to volumes of 20% water reposition. This does not happen for dry matter. It is not worth to irrigate with volumes superior to 40% water reposition if it is expected to stimulate the parameters number and length of buds. For reproductive parameters there were no differences among the different irrigation levels, all reaching productive levels according to an irrigation situation in Valdivia province (1194-1594 kg/ha) with the same type of plant age. An interaction was present among irrigation volume and frequency with number of buds, which confirms the importance of daily irrigation with 40% water reposition volumes, being not worth to irrigate with higher volumes