Abstract

Water is the most important production factor in agriculture, since even small restrictions to the water supply can result in decreased productivity. Due to climatic reasons, water supply is limited in many parts of the world, resulting in a need to develop techniques that increase the water use efficiency. Pulse irrigation consists of the application of an irrigation depth, relative to the actual irrigation needed, split throughout the day. The objective of this study was to verify the effects of pulse irrigation on cucumber plants that were either subjected to a water deficit or were sufficiently supplied with water, considering the hypothesis that the application of water during times of greater evapotranspiration demand will promote benefits to the crop in comparison with the continuous irrigation in the early hours of the day. A completely randomised design was used and the treatments were distributed in 3×4 and 4×4 factorial scheme in the first and second cycles respectively. The first factor was the replenishment of the irrigation depth relative to the crop evapotranspiration, while the second factor was the number of pulses; there were a total of 48 and 64 plots in the first and second cycles, respectively. The application of the treatments was started in the vegetative phase and in the reproductive phase for the first and second cycles respectively. It was concluded that smaller irrigation depths than the crop requires can be applied by pulses without resulting in a reduction in the vegetative growth in Japanese cucumber.

Key words: Drip irrigation, water savings, reduced irrigation depth, Cucumis sativus, protected environment.