Effects of Ssi1 Gene Controlling dm-type Internode Elongation Pattern on Lodging Resistance and Panicle Characters in Rice

The dm-type semi-dwarf mutant DMF-1 is controlled by the semi-dominant gene, Short second internode 1 (Ssi1), located in the region within ca. 20 cM on the long arm of chromosome 1. In order to elucidate the function this gene in relation to the lodging resistance and panicle characters in various genetic backgrounds, these agronomic characters were investigated by using DMF-1, Reimei (sd1 allele), six different F10 lines (DML-1 to -6) with homozygous form of Ssi1, and their parents. The experimental results showed that all the dm-type lines except for DML-6 (DMF-1 × Tan-Ginbozu) whose genotype belonged to the homozygous form of both Ssi1 and d35, significantly increased the lodging resistance, compared to their respective parents. On the other hand, although DMF-1 reduced seed production because of the high ratio of appearance of hull-cracked kernels, such a negative character had been improved in DML-1 (Kinmaze × DMF-1), DML-2 (Nipponbare × DMF-1) and DML-4 (Sasanishiki × DMF-1). Principal component analysis based on fifteen panicle characters also showed that these three F10 lines should be assigned to a group of normal cultivars. These results suggested that it is possible to develop a new semi-dwarf variety for practical use, expressing a high level of lodging resistance associated with the Ssi1 gene in various genetic backgrounds.

[1]  Z. Hong,et al.  The Rice brassinosteroid-deficient dwarf2 Mutant, Defective in the Rice Homolog of Arabidopsis DIMINUTO/DWARF1, Is Rescued by the Endogenously Accumulated Alternative Bioactive Brassinosteroid, Dolichosterone , 2005, The Plant Cell Online.

[2]  M. Yano,et al.  A Novel Cytochrome P450 Is Implicated in Brassinosteroid Biosynthesis via the Characterization of a Rice Dwarf Mutant, dwarf11, with Reduced Seed Length , 2005, The Plant Cell Online.

[3]  M. Matsuoka,et al.  A Rice Semi-Dwarf Gene, Tan-Ginbozu (D35), Encodes the Gibberellin Biosynthesis Enzyme, ent-Kaurene Oxidase , 2004, Plant Molecular Biology.

[4]  Z. Hong,et al.  A Rice Brassinosteroid-Deficient Mutant, ebisu dwarf (d2), Is Caused by a Loss of Function of a New Member of Cytochrome P450 Article, publication date, and citation information can be found at www.plantcell.org/cgi/doi/10.1105/tpc.014712. , 2003, The Plant Cell Online.

[5]  H. Satoh,et al.  Mutations in Panicle Development Affect Culm Elongation in Rice , 2003 .

[6]  Yukihisa Shimada,et al.  Loss-of-function of a rice brassinosteroid biosynthetic enzyme, C-6 oxidase, prevents the organized arrangement and polar elongation of cells in the leaves and stem. , 2002, The Plant journal : for cell and molecular biology.

[7]  G. S. Khush,et al.  Green revolution: A mutant gibberellin-synthesis gene in rice , 2002, Nature.

[8]  Masatomo Kobayashi,et al.  Loss-of-function of a Rice Gibberellin Biosynthetic Gene, GA20 oxidase (GA20ox-2), Led to the Rice ‘Green Revolution’ , 2002 .

[9]  M. Matsuoka,et al.  Loss of Function of a Rice brassinosteroid insensitive1 Homolog Prevents Internode Elongation and Bending of the Lamina Joint , 2000, Plant Cell.

[10]  H. Kitano,et al.  Dominant Gene, Ssi1 Expresses Semidwarfism by Inhibiting the Second Internode Elongation in Rice , 2000 .

[11]  H. Kitano,et al.  New dm-type Dwarf Mutants Varying in Internode Elongation Patterns are Controlled by Different Mutant Genes at the Same Locus in Rice (Oryza sativa L.). , 1999 .

[12]  M. Yano,et al.  Rice gibberellin-insensitive dwarf mutant gene Dwarf 1 encodes the alpha-subunit of GTP-binding protein. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[13]  H. Kitano,et al.  Suppression of the heterotrimeric G protein causes abnormal morphology, including dwarfism, in rice. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[14]  王 善本,et al.  Studies on Lodging in Rice Plants. , 1991 .

[15]  蓬原 雄三,et al.  BREEDING OF A NEW RICE VARIETY "REIMEI" BY GAMMA-RAY IRRADIATION. , 1967 .

[16]  J. E. Grafius,et al.  Lodging Resistance in Oats1 , 1954 .