Irrigation Depth and Carnauba (Copernicia prunifera) Straw Increase Water Use Efficiency in the Cherry Tomato in a Semi-Arid Region

Abstract

This research addresses irrigation strategies for saving water, including the use of irrigation depths of 50, 75, 100, 125 and 150% of the crop evapotranspiration (ETc) and a ground cover of carnauba straw, in evaluating the response of the cherry tomato (Solanum lycopersicum var cerasiforme L) submitted to different levels of water availability in soil with and without ground cover, in the semi-arid region of northeastern Brazil. The physiological components showed higher values under ground cover and when submitted to 100% ETc. The greatest number of total and commercial fruit was obtained when the soil was covered, and irrigated with depths of 75 and 100%. Carnauba straw with irrigation depths of 100 and 125% resulted in the greatest fresh fruit weight. The highest values for fruit diameter and length were achieved in the soil under cover. Maximum productivity, 11,404.20 kg ha^-1, was obtained at 107.5%, while for the soil with no ground cover, maximum productivity was 7,778.86 kg ha^-1, obtained with an irrigation depth of 140%. Based on the results, soil productivity is possible without a cover of carnauba straw, at an irrigation depth of 50.5%, which can generate savings of 3400 m³ water-cycle^-1 ha^-1. In addition, water use efficiency in the cherry tomato was 3.06 kg m^-3 and 1.95 kg m^-3, with and without ground cover respectively. It can be concluded that the use of carnauba straw makes it possible to reduce water consumption in the 'red' cherry tomato under conditions of water scarcity.