Morphology and inheritance of dwarfism in common buckwheat line G410 and its stability under different growth conditions

Mineo Minami¹, Akio Ujihara¹, and Clayton G. Campbell²

¹ Faculty of Agriculture, Shinshu University, 8304 Minamiminowa, Nagano 399-4598, Japan; ² Kade Research Ltd., Morden. Manitoba, R6M 1Y5, Canada.

Mineo Minami, Akio Ujihara, and Clayton G. Campbell. 1999. Morphology and inheritance of dwarfism in common buckwheat line G410 and its stability under different growth conditions. Breeding Science. 49: 27-32.

Abstract: The morphological characters of a dwarf common buckwheat line G410, its dwarf stability under different growth conditions and mode of inheritance were investigated. Dwarfism in G410 is a result of reduction in its first four internodes, especially in the second and third internodes from the soil. The other internodes and organs were not reduced in size. Therefore G410 showed the brachysm type dwarfism, which is valuable for both root lodging and stem lodging resistance. Although buckwheat is sensitive to growth conditions and its stem elongates longer under long day or high nitrogen conditions, the morphological characters of G410 were unaffected by seeding date, Plant density and nitrogen conditions. F₁ plants of G410 crossed with a normal variety, Botan-soba, appeared intermediate and segregation ratios in the F₂ and BC₁ F₁ generations fitted a single gene model. Therefore dwarfism of G410 was controlled by a single incompletely dominate gene, probably which is a new gene because all dwarfing genes reported previously are recessive. Under this inheritance system it is possible to distinguish genotypes by phenotype and to select dwarf homozygotes. These results indicate that G410 is a material worth further investigation for breeding lodging resistance in common buckwheat.

Key words: Fagopyrum esculentum, dwarfism, lodging resistance, morphology, stability, inheritance