The researchers studied different types of indica rice plants with large and small panicles to see how their root traits and activity affected their yield. They found that plants with larger panicles had higher root dry weight, longer roots, and more root absorption area compared to plants with smaller panicles. The length of roots per panicle, root dry weight per panicle, and root activity per panicle were key factors influencing panicle weight. By increasing these root traits, rice plants can produce larger panicles and potentially higher yields.