A Hunter Color Difference meter and a white-paint color chart were used to determine the degree of whiteness among 8 white-seeded Great Northern (GN) cultivars of Phaseolus vulgaris. A correlation coefficient of +0.84 was found between the 2 methods. The former method provided better separation of cultivars for degrees of whiteness than the latter method. Two genetic studies were conducted, with seed-coat whiteness determined by use of the white-paint color strip. ‘GN Emerson’ had the whitest seed-coat. The inheritance of seed-coat whiteness was investigated in 1978 using parents, F2s of the crosses Plant Introduction (PI) 165078 (bright white) with ‘GN Emerson’ (moderately bright white), ‘GN Valley’ (dull white) and ‘GN UI 59’ (dull white) and in the reciprocal cross ‘Bulgarian White’ (brightest white) × ‘GN UI 59’ (dull white). A quantitative pattern of inheritance was observed. Broad sense heritability estimates for this trait ranged from 46 to 57%. The Gardner and Eberhart model, Analysis II, was used in 1979 to estimate genetic effects for the trait in a 6 parent diallel cross involving ‘GN Emerson’, ‘GN UI 59’, ‘Bulgarian White’, ‘GN Star’ (dull white), ‘GN 1140’ (dull white) and ‘GN D-88’ (dull white). Additive genetic effects were predominant; but heterosis effects were also important, including significant effects for specific combining ability, and reciprocal crosses. ‘Bulgarian White’ showed high combining ability for brighter whiteness. The genetic data indicate that improvement of seed-coat whiteness in dry beans should be relatively easy to accomplish.
Published as Paper No. 6203. Journal Series. Nebraska Agricultural Experiment Station. Research was conducted under Project No. 20–36 and 20–40. Part of a thesis presented by Safi S. Korban to the faculty of the Graduate College of the University of Nebraska in partial fulfillment of requirements for the PhD degree.
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Graduate student. Professor, Department of Horticulture. Director. Panhandle Station. Scottsbluff, Nebr., respectively. The current address of the senior author is Department of Horticulture. University of Illinois. Urbana. Illinois 61801.
We wish to acknowledge grants received from Anna Elliott Foundation. University of Nebraska, and the Rocky Mountain Bean Dealers Association to support the research. We thank U.S. Western Regional Plant Introduction Station for the P.I. line. Kelley Bean Co. and Chester Brown Co., Nebraska, for seeds of several dry bean cultivars.
We appreciate the use of the Hunter Color Difference meter and laboratory facilities provided by Drs. G. Hosfield. M. Ubersax. and Wayne Adams. Michigan State University. East Lansing. Michigan. The typing assistance of Mrs. Waynetta Morningstar is gratefully acknowledged.