冷库贮藏条件下水稻光温敏核不育系种子活力研究

Study on Seed Vigor of Rice PTGMS Lines with Low Temperature Storage

为探究冷库贮藏条件下水稻光温敏核不育系种子活力的变化规律及种子的使用技术,本研究以在温度8~10℃、相对湿度55%的种子冷库中冷贮不同年份的准S、Y58S、凤S、广占63-4S为材料,对其活力及田间生长发育特性等进行研究。结果表明:水稻不育系种子的发芽势、发芽率、发芽指数和活力指数均随冷贮时间的延长呈下降趋势,冷贮5 a内的种子发芽率均大于60%,其浸泡液电导率随冷贮时间延长显著上升;种子的成苗率、根长、白根数、茎基宽和苗干重随冷贮时间的延长呈下降趋势,冷贮4~6 a内的种子综合秧苗素质差异不大。比较冷贮种子浸泡6、12、24 h的发芽率,冷贮时间长、活力低的种子以浸泡12 h为宜。冷贮种子出库后自然老化现象严重,自然条件下放置50 d后,发芽率下降显著。准S、Y58S、凤S的播始历期随冷贮时间的延长而缩短,所有不育系盛穗历期变化不明显。冷贮5 a内的不育系种子仍可正常使用,但出库种子须尽早播种,减少低活力种子浸种时间,并注意播始历期可能缩短的情况。

To explore the change rule of seed vigor and seed application technology of rice PTGMS lines with low temperature storage,Zhun S,Y58 S,Feng S and Guangzhan63-4 S stored in 8 ~ 10℃ temperature seed bank with relative humidity55% for different years were used as material to study the properties of seed vigor,growth and development in field,etc.The results showed: Germination energy,germination rate,germination index and vigor index of rice PTGMS lines seeds showed downward trend as the time of low temperature storage prolonged,and all of germination rate of the seeds within five years were over 60%. Conductivity in soaked solution of seeds was significantly increased with the prolonged low temperature storage time. Seedling rate,root length,white root,base stem width and seedling dry weight of seeds showed downword tread as the time of low temperature storage prolonged. There was no significant difference between two integral seedling qualities of seeds within 4 ~ 6 years in low temperature storage. Compared with the germination rate of low temperature storage seeds soaking for 6,12 and 24 h,the appropriate soak time of long time low temperature storage or low vigor seeds was12 h. A serious natural aging phenomenon occurred in low temperature storage seeds after out-storage. The germination rate was decreased obviously when seeds placing under natural condition for 50 d. The duration from seeding to heading of Zhun S,Y58 S and Feng S were shortened as the time of low temperature storage prolonged,while the variation of panicle duration of all PTGMS lines was not obvious. In conclusion,rice PTGMS line seeds with low temperature storage in 5 years could still be used normally. However,seeds out of low temperature storage should be seeded as soon as possible,as well as reducing the soaking time of low vigor seeds,and the possibility that the decreased duration from seeding to heading should be also considered.