Breeding of lndica CMS Line Jian 645A with High Outcrossing Rate and Good Grain Quality

Jian 645A is a new WA-type indica CMS line with late maturity and good grain quality,which is codeveloped by Hunan Jinjian Seed Industry Co.Ltd.and Changde Agricultural Science Research Institute from the testcross and Subsequent successive backcross of Jin 23A and 645,an elite line with good maintaining ability and fine grain quality selected from the cross between a colorless variant plant of quality rice variety Heibao and an F_7 plant of [Zhenshan 97B∥(Feigai B/V20B)F_(10)]F_4(///)[(Feigai B/V20B)F_(10)∥Jin 23B]F_4.It has a stable complete sterility with 100% of sterile plants,100% of pollen sterility and no selfed seed set,good flowering habits with early anthesis and high stigma exsertion rate(82.39% under natural conditions) resulting in a high outcrossing rate and a high yield in its multiplication and hybrid seed production,good grain quality with all of its twelve quality traits meeting the standards of the second class of fine quality rice issued by the Ministry of Agriculture of China.It has also a late maturity and a good combining ability with its hybrids yielding high and possessing good grain quality.In February,2006,Jian 645A was certified by Hunan Provincial Crop Variety Release Committee.