Compared with the corresponding R lines without eui, eR lines showed significant increasing in plant height, panicle exsertion, length of leaf, length of first internode, length of second internode. eR lines headed 4 days earlier, with little less number of tillers. F 1 of eR lines (e-hybrids) had similar performance in plant type and other major agronomic traits comparing to corresponding F 1 of R lines. E-hybrids showed a little increase in plant height and slightly increased the length of panicle, the length of panicle base exserting out of leaf sheath, the length of flag leaf and the first internode than F 1 of R lines. Moreover, e-hybrids headed a few days earlier, as well as showed greater grain weight resulting in higher yield potential than that of corresponding original hybrids.