低能氮离子注入同源四倍体水稻的生物学效应

以低能氮离子束为诱变源,对同源四倍体水稻进行注入处理后,对其生物学效应进行了研究。研究结果表明,同源四倍体水稻比二倍体水稻对低能氮离子束注入处理更敏感。在注入离子剂量为3×1017N+/cm2时,同源四倍体水稻所受到的损伤比二倍体水稻所受到的损伤更严重。4份同源四倍体水稻(即IR36(4)、IR28(4)、紫血稻(4)、明恢63(4))的成苗率分别是2.0%、3.5%、3.0%和4.0%,致死率非常高。在同样条件下,4份相应的二倍体水稻(即IR36(2)、IR28(2)、紫血稻(2)、明恢63(2))的成苗率分别是33.0%、31.5%、29.0%和24.5%,致死率也比较高。在经过注入处理后的当代群体内,4份同源四倍体水稻的平均变异频率为32.5%,而4份相应的二倍体水稻的平均变异频率为9.5%。在同源四倍体水稻IR36(4)和IR28(4)的变异群体内分别发现22株和14株结实率均达到75.0%以上的单株,其中在IR36(4)群体内有1单株的结实率高达91.89%;在紫血稻(4)的变异群体内发现2株具有双胚苗性状的单株;在二倍体水稻明恢63(2)的变异群体内发现1株具有红心米性状的单株。在第二代群体中,除了叶鞘变异和米质变异这两个变异性状能稳定遗传之外,其它变异性状在群体内都发生了明显的性状分离现象。同源四倍体水稻的高结实率特性和双胚苗特性表现出一定的可遗传性。

Biological Effects of Autotetraploid Rice after Ion Beam Implantation of Low Energy N+

Biological effects of autotetraploid rice after ion beam implantation of low energy N+ were studied. The results showed that autotetraploid rice were more sensitive to the ion beam implantation than diploid rice. Autotetraploid rice were more severely damaged when the dosage was 3×1017 N+/cm2. The frequencies of surviual plant from the autotetraploid rice, IR36(4)?IR28(4)?Zixuedao(4) and Minghui63(4), were individually 2.0%?3.5%?3.0% and 4.0%,but the numbers from the 4 diploid rice, IR36(2)?IR28(2)?Zixuedao(2) and Minghui63(2), were individually 33.0%?31.5%?29.0% and 24.5%. In the populations conducted by N+, autotetraploid rice(32.5%) showed higher mutagenic frequency than diploid rice(9.5 %). See sets of the 22 plants from IR36(4) and the 14 plants from IR28(4) surpassed 75.0%.The one mutagenic plant from IR36(4) was 91.89% in setting percentage. The two plants with the doubleembryo seedlings were successfully found in Zixuedao(4). The 1 plant with red rice character was selected in ......