Grain weight is one of the most important factors which affect the yield of rice to some extent, and the grain-filling speed and the formation of the ultimate grain weight is determined by the regulation and the balance of phytohormones in grain. The relationship between endogenous phytohormones in endosperm and the grain weight of rice was discussed in the paper using the two-line hybrid rice lines PeiliangyouE32 and Peiliangyou500 as materials. The results showed that the content of IAA, GA3 and Z in endosperm of rice grain increased first and then decreased, while the content of ABA is just...
