Multidimensional analysis of carrot-lettuce intercroppings under different combinations of population densities

Abstract

The objective of this paper was to evaluate the biological performance of carrot and lettuce intercropping systems under different combinations of population densities, using the bivariate analysis of variance and data envelopment analysis (DEA). The experimental design was the randomized complete blocks, in a 4x4 factorial scheme (carrot densities: 40, 60, 80 and 100% of the recommended sole crop density (RSCD); lettuce densities: 40, 60, 80 and 100% of the RSCD), with five replications. The recommended population density for carrot in sole crop is 500 thousand plants per hectare and for lettuce in sole crop is 250 thousand plants per hectare. Both bivariate method of variance and data envelopment analysis are quite effective in discriminating the best intercropping systems as assessed through component crop yields. The results of the yield efficiency as assessed by DEA models allow a simple statistical analysis of the intercropping experiment. The robustness of the bivariate analysis of variance method assures the validity of the results.