水稻种子休眠特性与耐藏性的关系

Dormancy characteristics and seed storage tolerance in rice

以2个具有休眠特性差异的籼稻Oryza sativa subsp.sativa品种[4K58(Ⅱ-32B休眠),4K59(Ⅱ-32B)]及其各自与不育系(Ⅱ-32A)的杂交F2代种子(C178,C179)为材料,采用人工加速老化方法获得不同老化天数(0,3,6,9d)的种子。通过测定种子的电导率值、单核苷酸浸出液质量浓度、发芽指标和幼苗生长指标等,探讨种子休眠特性与耐藏性的关系。结果表明:经老化后4K58种子的电导率值、单核苷酸浸出液质量浓度均显著高于4K59(P<0.05),其中单核苷酸浸出液质量浓度增幅最高,相差近14.5倍;而其发芽势、发芽指数等均显著低于4K59(P<0.05),平均发芽时间显著高于4K59(P<0.05),推测具有休眠特性的水稻种子更不耐储藏。研究还发现:老化后C178的核苷酸浸出液质量浓度、平均发芽时间显著高于C179(P<0.05),发芽率、发芽指数、幼苗苗高和苗质量均显著低于C179(P<0.05)。推测这种储藏特性可遗传至下代。

The relationship between rice seed storage tolerance and dormancy characteristics was determined for two Oryza sativa subsp, sativa （rice） euhivars with different characteristics of dormancy [4K58 （ Ⅱ-32B dormant）, 4K59 （ Ⅱ-32B）] and their F2 seeds （C178, C179） hybridized with a sterile line （ Ⅱ-32A） as materials. Different aged seeds （0 d, 3 d, 6 d, or 9 d） of these four varieties were acquired by the artificial accelerat-ed aging method. Seed conductivity, single nueleotide extract content, germination indices, and growth parame-ters of seedlings were measured in a CRD design with treatments of ck, 3, 6, 9 d with 3 replications. All data obtained were statistically analyzed with one-way ANOVA and least significant difference method （LSD） test. Results showed that seed conductivity, and single nueleotide extract content of aged 4K58 seeds were signifi-cantly higher than those of 4K59 （P〈0.05） with maximum discrepancy of single nueleotide extract content in multiples of 14.5. However, germination energy and germination index of 4K58 were significantly lower than those of 4K59 （P〈0.05） having a mean germination time that was significantly higher than 4K59 （P〈0.05）. Also the single nueleotide extract content and mean germination time of aged C178 seeds were significantly higher than those of C179 （P〈0.05）; whereas, germination percentage, germination index, shoot length, and fresh weight were significantly lower than C179 （P〈0.05）. Thus, storage properties may be passed on to suc-ceeding generations, and rice seed with dormant properties may not be suitable for storage.