A Spontaneous Mutation (rk~(drv)) for Expanded Red Flower Veins t the rk~d Gene for Dark Red Seed Coat Color

摘要

Recessive red seed coat colors in common bean are controlled at the red kidney locus Rk (Prakken, 1972; Smith, 1939 and 1961). Dry bean varieties with dark red kidney (garnet brown) seed coats carry the gene rk (Smith and Madsen, 1948) and usually carry other supporting recessive genes for seed coat color, viz., c~u and v or v~(lae). Numerous genetic stocks have been developed at Gainesville by backcrossing recessive genes into a Florida dry bean 5-593 as the recurrent parent. A backcross program totransfer the rk~d gene from the dark red kidney variety 'Montcalm' into the recurrent parent b v BC_3 5-593 (yellow brown seed coat genetic stock), resulted in the development of a genetic stock with seed coat genotype c~u g b v rk~d BC_1 5-593. A singleplant of c~u g b v rk~d EC_1 5-593 was observed to have a mutation for altered red flower veins, and this plant was crossed to the white banner stock wb BC_3 5-593 in Fall 1998. Four F_2 progenies from that cross were planted in the field in Spring 1999. A single F_2 plant selection for white flowers with red veins and dark red kidney seed coats was designated C g b v rk~(drv) BC_2 5-593 and was crossed with b v BC_3 5-593. Six F_2 progenies from that cross were planted in the field in Spring 2001. The proposed new gene symbol rk~(drv) has a superscript for "dark [red kidney] red vein [mutant]".