Intercropping forage cactus and sorghum in a semi-arid environment improves biological efficiency and competitive ability through interspecific complementarity

Abstract

The intercropping systems of species adapted to conditions of water deficit, such as sorghum (Sorghum spp.) and forage cacti (Nopalea spp. and Opuntia spp.), can contribute to an improvement in the biomass yield of semi-arid agricultural areas. This study aimed to evaluate the performance of intercropping cactus and sorghum as well as the biological efficiency and competitive ability of forage cactus clones and sorghum cultivars. The experiment was carried out in the Brazilian semi-arid region, in a randomised block design with 15 treatments and four replications. The treatments consisted of three forage cactus clones (‘IPA Sertânia’—IPA, ‘Miúda’—Miu and ‘Orelha de Elefante Mexicana’—OEM) and three sorghum cultivars (‘467’, ‘SF11’ and ‘2502’) under single configuration and the maximum number of combinations to comprise the intercropping systems. In terms of fresh and dry matter (221.73 and 47.04 Mg ha−1, respectively), the cactus-sorghum intercropping was 47% and 3.5 times more productive in terms of fresh and dry matter than the cactus single systems, with no effect on the quality of the forage. The forage cactus clones were dominant over the sorghum cultivars. The OEM-‘467’ configuration offered better stability (lower mortality), biological efficiency and crop competitiveness when compared to the single systems.