The study looked at how different traits in mutant rice plants affect grain yield under normal conditions and drought stress after flowering. The researchers found that traits like plant height, number of tillers, and panicle length were closely linked to grain yield in both normal and drought conditions. They also discovered that some traits had a stronger impact on grain yield under drought stress compared to normal conditions. This suggests that certain characteristics in rice plants can help them cope better with drought, ultimately leading to higher grain yields.