The objective of this study was to evaluate the changes in chemical properties of soil, growth and productivity of crops in a cowpea/corn rotation irrigated with water of different salinities. The experiment was conducted under field conditions in randomized block design in a factorial scheme with four treatments and five replications totaling twenty plots. The treatments consisted of plants irrigated with well water of ECw of 0.8 (T1), 2.2 (T2), 3.6 (T3) and 5.0dS m-1 (T4). In the first crop with cowpea (dry season) the space used was 0.8m between rows and 0.3m between plants, with two plants per hole. The same plots were utilized for the cultivation of corn (rainy season), using a spacing between rows of 0.8m and 0.2m between plants and one plant per hole. During the trial period, the chemical properties of soil, plant growth, productivity and partitioning of dry matter were evaluated. The use of saline water during cultivation of the cowpea in the dry season increased the salinity and sodicity of the soil, which reduced the growth and productivity of cowpea. High rainfall before and during the cultivation of corn eliminated the possible negative effects of salinity in this crop. The high yield of crops and the relatively small alteration in the salt content of the soil suggest the feasibility of using cowpea/corn crop rotation under conditions similar to this study.
Vigna unguiculata; Zea mays L.; cowpea; productivity; salt tolerance
