Post-harvest indexes and colour parameters from arugula–beet intercropping under green manuring and population density

- In this study, the objective was to determine the post-harvest indexes of arugula leaves and beet roots in intercropping under a biomass mixture of di ff erent green manures at diverse arugula population densities in two cropping seasons in a semi-arid environment. The experimental design was a randomised complete block design, with treatments arranged in a 4 × 4 factorial scheme with four replications. Treatments consisted of the combination of equitable amounts of Merremia aegyptia and Calotropis procera biomass (20, 35, 50 and 65 t ha − 1 on a dry basis) and arugula population densities (400,000, 600,000, 800,000 and 1,000,000 plants ha − 1 ). The characteristics evaluated in the arugula culture were titratable acidity, pH, and soluble solid and total soluble sugar content. In the beet crop, the same characteristics were evaluated in arugula, in addition to the betalain concentration and the internal colour parameters of the tuberose roots. Arugula showed the best post-harvest indexes when fertilised with green manure biomass amounts of 20, 20 and 65 t ha − 1 at a population density of 1,000,000 plants ha − 1 , while beet showed the best indices with green manure amounts of 65, 41, 36 and 40 t ha − 1 with an arugula density of 1,000,000 plants ha − 1 . The best colour parameters of beet roots were obtained with green manure amounts of 30 and 32 t ha − 1 at an arugula density of 400