Study On The Characteristics Of Three New Dual-purpose Genic Male Sterile Lines

To clarify the agronomic traits,critical sterility inducing temperature,out-crossing characteristics and combining ability on rice quality of the three newly breeding dual-purpose sterile lines.In this study,the dual-purpose genic male sterile line C815 S,which is currently used in large-scale application,was used as a control to analyze the characteristics of the newly breeding dual-purpose sterile line YangS,HaoS and 166 S.Using these three sterile lines as the female parent,incomplete diallel cross with the four restorer lines of Wushansimiao,E33,Yuenongsimiao and Huazhan,analyzing the combining ability on rice quality traits.The results were as follows:(1)Sowing in Changsha in early May,the duration form seeding to heading of YangS and the control C815 S were the same,and YangS had compact plant type.The duration from seeding to heading of HaoS was longer than the control,the leaves of main stem was more than the control,the length of first internode from top was shorter,the spikelet per panicle and the spikelet density were larger,the panicle length was longer,and the agronomic trait was excellent.The duration form seeding to heading of 166 S and the control C815 S were the same,and its plant height was shorter,the leaves were wider,the tillering ability was higher,the spikelet per panicle was larger and the panicle length was particularly longer.(2)The flowering time of YangS was concentrated,and the open peak period was from 11:00 to 13:30,reaching the flowering peak at 12:30,the necking rate was lower,the stigma vitality was higher.the flowering time of HaoS was relatively scattered,and the open peak period was fom 11:00 to 13:00.The sterile line had longer spikelet opening period and larger spikelet spacing,the dual stigma exsertion rate and total stigma exsertion rate were extremely high,the stigma vitality and the necking rate were slightly higher than the control.The outcrossing characteristics of HaoS was very good.The peaking period of the sterile line 166 S was 9:00-11:00,the flowering peak period was earlier,and the flowering peak was reached at 9:30.The rate of spikelets flowering before noon,the stigma vitality and the necking rate were higher.It may be necessary to apply more “920” to remove the neck during seed production.(3)The critical sterility inducing temperature of YangS was lower than 22.5?,the critical sterility inducing temperature of 166 S was between 22.5?and 23.5?,and both had lower critical sterility inducing temperature.The critical sterility inducing temperature of HaoS was slightly higher than 23.5?,which was high.The next step will be to reduce the critical sterility inducing temperature and seed production risk of HaoS by expanding planting groups and pressurization option.(4)The analysis of rice quality traits showed that the differences on the general combining ability and special combining ability were significant or extremely significant on eight traits of brown rice rate,milled rice rate,grain length,length-width ratio,chalkiness grain and chalkiness degree,alkali spreading value and amylose content,indicating that the inheritance of these eight traits was controlled by both additive effect and non-additive effect.The traits of brown rice rate,milled rice rate,grain length,length-width ratio,alkali spreading value and amylose content were mainly controlled by the additive effect of male sterile lines.The traits of chalkiness grain and chalkiness degree were mainly controlled by the additive effect of the restorer line.The traits of head milled rice rate and gel consistency were mainly controlled by the non-additive effects.Sterile line YangS,166 S and restorer line Wushansimiao,Yuenongsimiao made it easier to obtain combinations of good appearance quality and cooking quality.