 Tropical maize hybrid, a single cross of flint and dent in bread lines, is an important crop throughout the Americas and Africa. Crop yield, however, is highly dependent on nitrogen availability, and fertilizers are therefore often necessary to increase production. Developing more nitrogen-efficient maize would not only cut costs for farmers, it would also increase crop yield and reduce environmental impacts. But how do you make a plant more nitrogen-efficient? The performance and production of crops can be improved by selectively crossing individuals with desired traits. When such plants are crossed, they produce hybrids that are often bigger, stronger, and more vigorous than either of the parent plants. By carefully choosing which individuals are used in creating these hybrids, specific traits such as nitrogen efficiency can be selected for. In an attempt to enhance hybrid prediction accuracy and the efficiency of tropical maize selection, a team of Brazilian researchers evaluated the success of various selection indices in combination with an emerging method called multi-trade genomic prediction. This method allows for the incorporation of genetic information, SNP traits in this case, and allows breeders to consider multiple traits, such as plant height and grain yield simultaneously. Thus the grain yield of maize hybrids was evaluated under low and normal nitrogen levels. Then the team used four indices of selection and the genomic data to compare the accuracy of single and multi-trade methods in predicting hybrids. The study found that because it takes into account performance under optimal and nitrogen-stressed conditions, using the harmonic mean provided the highest prediction accuracy. Accuracy was further increased when selection indices were combined with multi-trade genomic prediction. By testing several selection methods, this study provides important insights into how best to increase the speed and efficiency of selection and create superior maize cultivars. Developing new nitrogen-efficient plants is a critical step towards creating a more sustainable crop while increasing production to meet future demands of an ever-increasing human population.