Production of cytoplasmic male sterile and its maintainer by using asymmetrical protoplast fusion and incorporation of isolated nuclei.

1989 Fiscal Year Final Research Report Summary

• Project/Area Number: 63560001
• Research Category: Grant-in-Aid for General Scientific Research (C)
• Allocation Type: Single-year Grants
• Research Field: Breeding science
• Research Institution: Chiba University
• Principal Investigator: MII Masahiro Chiba Univ, Fac. Hort, Assoc, Prof., 園芸学部, 助教授 (30093074)
• Project Period (FY): 1988 – 1989
• Keywords: Carrot / Daucus carota / Somatic embryo / Cybrid / Asymmetrical fusion / Cytoplasmic male sterility / Iodoactamide / X-ray

Research Abstract

Introduction of cytoplasmic male sterility into normal fertile plants and vice versa were tried by using asymmetrical protoplast fusion technique and incorporation of isolated nuclei in carrot.
Both donor and recipient cell lines of cytoplasm were fused by PEG treatment after irradiation with 60 kR x-ray and treatment with 10 mM iodoactamide, respectively. Irrespective of the cell materials used, many plantlets were regenerated from the fusion products via somatic embryogenesis. However, no plants with altered male sterility were obtained. In the control cultures treated with only x-ray or with IOA, some escaped colonies were obtained presumably due to the complementation. Therefore, stronger treatments were applied to suppress the escape before fusion treatments. these treatments reduced the number of survived colonies which eventually developed into embryos. Further experiments are now in progress.
Isolation of nuclei from the embryogenic cell cultures was extremely difficult, whereas that from vacuolated non- embryogenic cells was relatively easy. However, the use of nuclei isolated from non-embryogenic cells was not suitable for obtaining plant regeneration after nuclei Incorporation. Further experiment is required to get nuclei from embryogenic cells.