BGS 160, Enhancer of minute, min2

Enhancer of minute = en-min

Monofactorial recessive, but expressed only in plants homozygous for the min1.a (semi-minute dwarf 1) allele (3).
Location is unknown.

Plants are extremely dwarfed with the adult plant being less than 5 cm tall. The leaf blade and sheath are very short and thick and have a whitish dark green color. Roots are thick and short with C-tumor-like swelling at their tips. No spikes are formed; hence, the stock must be maintained as a heterozygote at the min1 locus (2). Among the kernels produced by heterozygous plants, those that will give rise to minute plants have a markedly shrunken endosperm (1, 2). Tissues of the plant are mixoploid with 2x, 3x, 4x, and up to 60x cells being formed by abnormal cytokinesis (1, 2).

A spontaneous mutant at the min1 locus in Kaiyo Bozu (OUJ378, PI 467405) permits expression of en-min (2).

Natural occurrence of en-min (OUL921, GSHO 266) in Kaiyo Bozu (OUJ378, PI 467405) (2).

en-min in a line of Kaiyo Bozu (GSHO 266) that is heterozygous at the min1 locus.

1. Morikawa, T., and E. Gomi. 1996. Pleiotropism of minute gene (min) of barley. p. 530-532. In A.E. Slinkard, G.J. Scoles, and B.G. Rossnagel (eds.) Proc. Fifth Int. Oat Conf. & Seventh Int. Barley Genet. Symp., Saskatoon. Univ. of Saskatchewan, Saskatoon.
2. Takahashi, R., A. Mochizuki, and J. Hayashi. 1955. [Heritable mixoploidy in barley.] Nogaku Kenkyu 43:51-62. [In Japanese.]
3. Takahashi, R., A. Mochizuki, and J. Hayashi. 1959. Heritable mixoploidy in barley. II. On the semi-minute. Nogaku Kenkyu 47:95-104. [In Japanese with English summary.]

R. Takahashi. 1972. Barley Genet. Newsl. 2:185.

T. Konishi and J.D. Franckowiak. 1997. Barley Genet. Newsl. 26:186.