The study compared how rice varieties with different panicle types fill their grains and looked at their physiological characteristics. They found that loose panicle rice varieties fill grains faster and have more vigorous grains compared to tense panicle varieties. Even though loose panicle varieties have lower chlorophyll content and root bleeding intensity, the decrease in these factors is less compared to tense panicle varieties. In conclusion, there is a connection between grain filling characteristics and chlorophyll content and root bleeding intensity in rice varieties.