Estratégia de utilização de água salina no cultivo de palma forrageira ‘gigante’

Abstract

The forage cactus is considered a xerophilous plant and therefore presents adaptation to the adverse conditions of the semiarid. It is a forage reserve of significant importance in the sustainability of the regional cattle ranch, a segment strongly affected by the scarcity of food in the seasonality period. The objective was to evaluate the forage cactus cultivar Gigante submitted to combinations of different blades and watering shifts with saline water. The treatments, seven conditions of application of water: without irrigation; 5 liters of water per linear meter every 15 days; 7% of the reference evapotranspiration (ETo) with irrigation period (IP) of 15 days; 15% of the ETo with IP of seven days; 33% of ETo with IP of Three days; 50% of ETo with two days IP and 100% of ETo irrigated daily, were arranged in a randomized complete block design with four replications.. The following were evaluated: electrical conductivity, chemical characteristics and soil water content; irrigation system; chlorophyll fluorescence; plant height; number, length, width and area index of the cladodium; Production of green and dry mass and water use efficiency. The use of irrigation with saline water (3.6 dS m-1 ) in forage cactus does not promote the salinization of red-yellow latosol after two years of cultivation and rainy season. Drip irrigation system with in-line maze type emitters, with the use of saline water does not promote reduction of water application efficiency. The use of saline water (3.6 dS m-1 ) in forage cactus irrigation does not provide a stress condition to the culture by the presence of salts. The condition of application of saline water of 33% of the ETo with IP of three days promotes increment of the variables height, number of cladodes, cladode area index, green mass production and forage palm dry.