The researchers analyzed the characteristics of rice panicles from 8 different varieties with the same primary branches. They found that grain yield, panicle number, and grain weight were closely related, with total branch length and panicle length playing a role. The distribution of grain number, unfilled spikelets, and grain weight on the panicle axis was consistent across varieties. The upper part of the primary branch length had three distinct types, with secondary branches and grains showing shuttle-like distributions. The seed setting rate of secondary branches on upper panicles was higher than in the middle or lower parts.