The researchers evaluated different types of tropical maize hybrids to see how well they could grow in hot conditions. They tested 49 hybrids in a farm in Karnataka and measured traits like plant height, cob length, and yield. Some hybrids, like ZH16848, ZH16866, and ZH16880, showed higher grain yield and were more tolerant to high temperatures. This study found that there is a lot of variation among the hybrids, which could be useful for breeding new maize hybrids that can handle heat better.