The use of mulch in cultivating the forage cactus optimizes yield in less time and increases the water use efficiency of the crop

Abstract

AbstractMeasurements of crop evapotranspiration (ETC) and crop coefficients (kC) in cactus have not yet been adjusted for the phenological stage using conservation practices (i.e. mulching). In this study, soil water dynamics, ETC and kC were measured in the forage cactus under cultivation systems with (WM) and without (NM) the use of mulch in the semi‐arid region of Brazil. Opuntia stricta was subjected to irrigation depths based on a percentage of the reference evapotranspiration (ET0) (rainfed, 25, 50, 75 and 100%) and to two systems of cultivation: WM and NM. Over time, the phenophases (φPh) were established; the soil water balance components were calculated and the crop yield was evaluated at harvest. The use of 8.2 Mg ha−1 mulch led to almost no reduced water consumption by the crop when compared to the NM system; however, the mulch did maximize yield, at 839°C day, when irrigated with 50% ET0. The kC value was higher under the WM system, with the differences decreasing throughout the cycle (φPhI, 36%; φPhII, 27%; φPhIII, 23%; φPhIV‐HT, 17%; and φPhIV‐RF, 14%). Therefore, the use of mulch in cultivating the cactus optimized forage production in less time and significantly increased the water use efficiency of the crop.