In this article,we analyzed the status of 34 early hybrid rice combinations which were registered and released in Hunan Province during 1986—2005,and compared the differences in major characters between twoline early hybrid rice and three-line early hybrid rice based on the data of the regional trials from 2001 to 2005.

Crossing it with Zaohui 89,a new two-line early hybrid rice combination,Jinliangyou 289,was developed and it was characterized with both high yield and good grain quality.

Zhuliangyou 08,developed by the Agricultural Research Institute of Xiangtan,Hunan,is a new two-line early hybrid rice combination derived from the corss of Zhu 1S,a PTGMS line which is of low critical sterility-inducing temperature and wide compatibility,and Tanzao 08,a newly-developed high-yielding and multi-resistant early indica rice line.

Jinliangyou 4,a new two-line early hybrid rice combination with both high yield and good grain quality,was developed by crossing Jinshan S-2 (a PTGMS line with low critical temperature and good grain quality) with the restorer line Zao R-10.

Studies on the combining ability of quality characters in early hybrid rice;

Effect of nitrogen distribution, planting density, and transplanting methods on the yield of early hybrid rice T You 7889;

Six early hybrid rice combinations were divided into two maturing groups: early group and late group,and a comparison was conducted on the growth and developmental process and yield characteristics between these two groups.