Regulation of early embryogenesis in crops
| Project/Area Number |
62480031
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
Breeding science
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| Research Institution | Tohoku University |
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Principal Investigator |
NAGATO Yasuo Fac. Agr., Tohoku Univ. Associate Prof., 農学部, 助教授 (10143413)
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| Co-Investigator(Kenkyū-buntansha) |
TAKEDA Genkichi Fac. Agr., Tokyo Univ. Prof., 農学部, 教授 (90134501)
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| Project Period (FY) |
1987 – 1989
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| Project Status |
Completed (Fiscal Year 1989)
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| Budget Amount *help |
¥6,300,000 (Direct Cost: ¥6,300,000)
Fiscal Year 1989: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1988: ¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 1987: ¥3,800,000 (Direct Cost: ¥3,800,000)
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| Keywords | embryogenesis / organ differentiation / embryo culture / mutation / apomixis / rice / Chinese chive / 不定胚発生 |
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| Research Abstract |
We have identified in total 28 single-gene, recessive mutants on embryogenesis. They were characterized anatomically and classified into several groups; 1.lethal at the early globular stage, 2.arrested at the globular stage, 3.arrested at the early differentiation stage, 4.abnormal organ position, 5.shootless, 6.abnormal organ morphology, 7.reduced embryo size, and 8.wide phenotypic variation. Of them, group2 mutants were examined histochemically to know they were lethal or not. They all showed glutamic dehydrogenase and malate dehydrogenase activities even after the imbibition of water by dry seed, indicating that they were not lethal but changed their developmental pathway not to differentiate any organ. Group8 mutants showing wide phenotypes in spite of single mutation are considered to be mutants of regulatory genes each regulating the expressions of several developmental genes. It is considered that organ differentiation during embryogenesis is performed through the hierarchical regulation of expressions of many stage- and/or tissue specific genes.
We tried to culture young embryos under various combinations of IAA and kinetin and a seedling was obtained from coleoptilar embryo fo 0.18mm long cultured on MS medium supplemented with 1O-7M kinetin and without IAA. Further, we examined the conditions for culturing smaller embryos. Nurse culture using 0c cell line enabled to obtain seedling from 0.12 mm long embryo without plant hormones. Also it was revealed that high osmotic pressure was effective for culturing smaller embryos.
As for apomixis, we estimated the degree of parthenogenetic development in Chinese chive. Most cultivars examined showed high degree of parthenogenetic development of more than 90%. The degree of apomixis, which was a combined result of unreduced embryosac formation and parhtenogenesis, was also higher than 90% in most cultivars.
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Report
(4 results)
Research Products
(15 results)
