Preliminary Study of Rice Mutants Induced by High Hydrostatic Pressure

Abstract:

Indica rice (Oryza saliva L.) varieties Yuexiangzhan, Yuefengzhan and Japonica rice (Oryza saliva L.) 998, 999, Bijing 38, which were treated by high hydrostatic pressure, as well as their mutants (Yuebianchang, Juwuba, Yuefengyabian 1 to 5, and Bixian), were used to study the effect of high hydrostatic pressure on the growth and agronomic traits of rice. The seeds of all varieties were soaked for 10 h at room temperate, then treated under 75 MPa for 12 h after the seeds germinated. The results showed that the plant height, panicle number of M₁ population of Yuexiangzhan and 998 increased obviously compared with the control, but no marked difference was observed in traits of Yuefengzhan, 999, and Bijing 38. Many traits including plant height, panicle number, grain number per panicle, grain length and 1 000-grain weight of Yuebianchang and Juwuba from M₂ to M₄ were different from the control, and all of the traits among M₂, M₃ and M₄ were stable. Plant height was segregated in M₃ population of Yuefengyabian 1 to 5 except Yuefengyabian 2. Some mutants with larger grain and/or longer awn were found in M₄ population of Yuefengyabian 4. Plant height, panicle length, grain length and grain number per panicle increased significantly in M₂ to M₄ of Bixian compared with Bijing 38, but seed setting percentage and 1000-grain weight obviously decreased. Twin or trine seedlings were observed from one seed when the treated seed of Yuefengzhan germinated in plate. This results indicate that high hydrostatic pressure not only influences rice growth and development, but also induces mutation.