2025-08-262025-08-262022-03-04https://repositorio.ifal.edu.br/handle/123456789/1173Forage cactus constitutes an important alternative for forage support for the semiarid Northeastern region of Brazil. Accordingly, a worthy mentioning technology to increase its productivity is the suplementar irrigation. This academic work aimed to study the growing and production features of carmine mealybug resistant cactus genotypes, subjected to varying depths of brackish water suplementar irrigation. Experiments procedures were conducted using water collected from the Poço Doce ́s site, located in the minicipality of Piranhas. In terms of methodology, the tests were carried out on a randomized blocks basis with 4 replications in the split-plot scheme, with the plot consisting of five saline water replacement depths: L1 = 0 mm/month, 7.5 mm/month, 15 mm/month, 22, 5 mm/month and 30 mm/month. These aforementioned replacement depths were divided into three monthly applications, and the subportion was composed of the two varieties of forage cactus (Orelha de Elefante Mexicana and Miúda). Using drip tapes to situate the irrigation system, the following characteristics were evaluated: final plants quantity (plants/m2); number of rackets per plant; height and width of plants (m); primary, secondary and tertiary rackets length (cm), width (cm), thickness (mm), and green mass (kg/racket); dry matter percentage and productivity (Mg/ha). We found that optimal forage cactus growth and productivity were achieved for irrigation depth of 15 mm/month. Last, but not least, we concluded that the Orelha de Elefante Mexicana variety showed better growth and productivity characteristics than the Miúda one, and in addition, it presented small percentages of dry matter regardless of the amount of irrigation.ptOpuntia strictaNopalea cochenilliferaSemiáridoÁgua salinaSemiaridBrackish WaterTrabalho de Conclusão de CursoENGENHARIAS