EFECTO DE NIVELES Y FRECUENCIAS DE RIEGO POR ASPERSIÓN EN PAPA (Solanum tuberosum L.) *

Abstract

Effects of different levels and frequencies of sprinkler irrigation on potatoes (Solanum tuberosum L.).
The aim of this study was to establish the response of potato crop to different sprinkler irrigation levels and frequencies, according to requirements at the different crop phenological stages. During 1998/99 and 1999/2000 seasons, potato crops were planted at "Los Copihues" farm in the IXth Region of Chile using a completely randomized experimental design. Treatment 1 consisted of weekly irrigation between December and February of 500 mm per season. Treatment 2 consisted of weekly irrigations during January and biweekly irrigations in February, with 356.5 mm and 320.4 mm of water, respectively for the two seasons. Treatment 3 involved biweekly irrigation during January and February, with a total of 254.6 and 208.4 mm of water during the two seasons. Treatment 4 used biweekly irrigation in January and no irrigation in February, with a total of 152.7 and 103.1 mm of water applied during the two seasons. There were significant differences of yield between treatments 1 and 4 in both seasons. The application of more than 500 mm of water during the crop period, with weekly frequency between December and February, produced the highest yields, reaching 49,720 and 43,861 kg ha-1, respectively. Treatments 2 and 3 showed similar responses between seasons. Although their yields were lower, the differences between them were not statistically significant. These results confirm that potato crop shows a positive response to frequent irrigation spread uniformly over the period from late- December to February. Weekly irrigation, with 500 mm of water applied, produced higher percentage of tubers greater than 65 mm in size. This percentage may even be more than 50% of the total production.