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The inheritance of two new induced mutations for spindly branch was investigated in common bean (Phaseolus vulgaris L.). Each mutant was found to be controlled by a recessive gene. Allelism tests were performed beween a previously reported spindly branch mutant (sb) and the two new spindly branch mutants; the new mutants were found to be nonallelic to sb and to each other. The gene symbols sb-2 and sb-3 are proposed for the new mutants. Repulsion phase F₂ linkage tests were made for all nine combinations of reclining foliage (rf) and sb among the two mimic mutant series rf, rf-2, rf-3 and sb, sb-2, sb-3. No linkages were detected.

A cross was made between gri (gray-white seedcoat) and p (pure-white seedcoat) using genetic stocks gri BC₂ 5-593 and p BC₂ 5-593 developed to carry only a single recessive allele for seedcoat color in an otherwise all-dominant genetic background. The recurrent parent, 5-593, is a Florida dry-bean breeding line with bishops-violet flowers, determinate habit, small seed size, shiny black seeds, and seedcoat genotype T Mar P [C r] D J G B V Rk. The F₁ progeny from the above cross between gri and p had the flower color pattern and seedcoat color of the griseoalbus character (gri), but had less intense color expression. Therefore, I hypothesized that gri is an allele at the P locus (allelic interaction). The hypothesis of allelism was confirmed in the F₂, which failed to segregate for bishops-violet flowers and black seed, i.e., no complementation was evident. The symbol p ^gri is proposed for the new allele at P, where the dominance series is P > p ^gri > p. The gene for gray-white seeds in gri BC₂ 5-593 was shown to be allelic to Lamprecht's gri gene in V0059 (PI 527716).

The effects of gri on seed coat and flower color were investigated in a study using Lamprecht line V0400 (PI 527735) as the known source of gri. Seed and flower color data were taken on observations of F₂, BC₁-F₂, and BC₂,-F₂ populations from crosses of V0400 with the recurrent parent S-593. Segregation was observed for a unique flower color pattern: wing petals have a very pale tinge of blue (laelia), and the banner petal has two violet dots (≈3- to 4-mm diameter) on a nearly white background. This very pale laelia flower color cosegregates with gray-white seed coats produced by gri. Furthermore, the very pale laelia color depends on the action of V for expression and is extinguished by v, which produces pure white flowers. Thus, it was demonstrated that the very pale laelia flower color, for which Lamprecht tentatively proposed the gene symbol v^pal, is not controlled by an allele at V but is a pleiotropic effect of gri. It was also demonstrated that Lamprecht line V0060 (PI 527717) carries v^lae, not v, as indicated by the genotypic notes accompanying the Lamprecht seed collection.

Common bean (Phaseolus vulgaris L.) seedcoats can have partly colored patterns such as the new two-points pattern, which has an unknown genotype. The gene t ^cf (derived from PI 507984) expresses partly colored seedcoat pattern with colored flowers. A genetic tester stock t ^cf two-points BC₃ 5-593 was derived from PI 507984 by backcrossing to the recurrent parent, Florida dry bean breeding line 5-593, which has black self-colored seeds and purple flowers due to the genotype T P V. A series of test crosses were made between t ^cf two-points BC₃ 5-593 and three genetic tester stocks: t z j ^ers white BC₃ 5-593, t z bip bipunctata BC₃ 5-593, and t z virgarcus BC₃ 5-593. All three test crosses were studied in F₁ and F₂ populations, and the latter test cross in F₃ progenies derived from 80 randomly selected F₂ plants. The two-points pattern was never observed with white flower plants expressed by t/t, supporting the hypothesis that t^cf is necessary for two-points expression. The complete genotype for two-points was found to be t ^cf z j ^ers. The t ^cf gene expresses more extensive colored zones in partly colored seedcoats than t. For example, t ^cf z J expresses self-colored seedcoats, whereas t ^cf/t z J expresses white ends pattern and t z J expresses virgarcus. Similarly, the t ^cf z j ^ers genotype expresses two-points pattern, whereas t z j ^ers expresses white seedcoat; and t ^cf/-z J/j ^ers expresses PI type pattern, whereas t z J/j ^ers expresses weak virgarcus pattern.

The inheritance of intensified anthocyanin expression (IAE) in a syndrome of plant organs of common bean (Phaseolus vulgaris L.) was investigated. A selection from accession line G07262, having white flowers with blue veins on the wing petals and a long, white micropyle stripe on black seedcoats, was used as the source of IAE syndrome. G07262 was crossed with three genetic tester stocks based on Florida dry bean line 5-593, which has the flower and seedcoat genotype T P [C r] Z J G B V Rk. The tester stocks were 5-593 (black seed and bishops violet flowers), t z bip bipunctata BC₁ 5-593 (a partly colored seedcoat), and v BC₂ 5-593 (mineral brown seedcoat and white flowers). Analysis of the F₁ and F₂ data from the test cross G07262 × t z bip bipunctata BC₁ 5-593 demonstrated that 1) G07262 has genotype t p ^mic V; 2) genotype t/t prevents expression of IAE syndrome by a dominant gene (Prp ⁱ -2) carried cryptically by G07262, i.e., T/-is required for expression of the gene; and 3) Prp ⁱ -2 may (preliminary data) express blue veins on white flowers with t V. From the cross with v BC₂ 5-593, an F₄ selection for white flowers with red banner back and mineral brown seedcoats (due to v) was made. When the F₄ selection was crossed with 5-593, analysis of the F₂ progeny demonstrated that G07262 carries a dominant gene for IAE syndrome, which expresses with V/- but not with v/v. From the test cross 5-593 × G07262, a series of additional cycles of selection and test crosses (including the dark red kidney tester c ^u b v rk ^d BC₁ 5-593) were made, and two new two-colored seedcoat patterns were developed that have never been previously reported. In a test cross with one of them, F₂ data demonstrated that the dominant gene for IAE syndrome from G07262 is independent of the C locus, and the gene symbol Prp ⁱ -2 is proposed for this IAE syndrome gene to distinguish it from the previously reported IAE syndrome gene [c ^u Prp ⁱ]. A gene symbol reconciliation was made for all previous work with inheritance of IAE syndrome and purple pod genes without the syndrome.

The P locus in common bean (Phaseolus vulgaris L.) can express complete absence of color (white) in seedcoats and flowers with p (with B V) or a pale grayish white seedcoat and nearly white flower with p ^gri, but P has never been considered a seedcoat pattern locus. Genes controlling seedcoat colors and patterns have been backcrossed into the recurrent parent 5-593 with black seedcoats and violet flowers. The cross, p BC₃ 5-593 × t stp ^mic BC₃ 5-593 (black seeds with a long white micropyle stripe and fibula arcs), failed to show evidence of genetic complementation in either F₁ or F₂ progeny, leading to the hypothesis that P and Stp are allelic. Five cross combinations between two recessive P alleles (p BC₃ 5-593 and p ^gri BC₃ 5-593) and three recessive alleles at the stippled seedcoat gene Stp (stp BC₃ 5-593, stp ^hbw BC₃ 5-593, and stp ^mic BC₃ 5-593) expressed no genetic complementation in seedcoats and flowers of F₁ progeny and confirmed the allelism hypothesis. New gene symbols are proposed for the recessive alleles at Stp, viz., p ^stp for stp, p ^hbw for stp ^hbw and p ^mic for stp ^mic. The dominance order at P is P > p ^mic > p ^hbw > p ^stp > p ^gri > p. Crosses were made between t self-colored BC₃ 5-593 and three other parents—p ^stp BC₃ 5-593, p ^hbw BC₃ 5-593, and p ^mic BC₃ 5-593—to explore interactions between the pattern genes T and P; and segregation for seedcoat patterns in F₂ was discussed. The hypothesis was proposed that the T locus regulates expression at P, or the biosynthetic step regulated by P.

The genetics of the vermilion flower color (more orange than scarlet or salmon red) of Phaseolus coccineus L. is largely unknown, but the gene Sal for salmon red is the gene essential for its expression. Lamprecht line M0169 (PI 527868) expresses salmon red flowers with vein pattern on the wing petals and black seedcoats. M0169 (Sal Am and an unknown gene that inhibits the scarlet flower color expression of Am) was crossed with v BC₃ 5-593 (sal am and no inhibitor gene, expressing white flowers and mineral brown seedcoats). Line 5-593 is a Florida dry bean (Phaseolus vulgaris L.) line used as the recurrent parent for development of genetic stocks. The F₂ from Sal Am V ^wf BC₁ 5-593 (scarlet flowers, black seedcoats) × v BC₃ 5-593 (white flowers, mineral brown seedcoats) supported the hypothesis that a partly dominant gene Am changes salmon red to scarlet flower color and that Am has no expression with sal. The F₃ progeny test of 27 random F₂ parents from the above cross supported the hypothesis of a single partly dominant factor (Am) with no expression without Sal, where only Sal/Sal Am/Am completely eliminates the flower vein pattern (VP) of Sal. F₄ progeny tests of 29 random F₃ parents derived from a F₂ selection with Sal/Sal Am/am V ^wf/v supported the hypothesis that Am is linked to V (cM = 9.4 ± 1.93) and the hypothesis that Am is linked with a dominant gene (tentative symbol Oxb) that (with Sal v) changes seedcoat color from mineral brown with red haze to oxblood red. Another F₄ progeny test of seven selected F₃ parents with Sal/Sal Am/am v/v and oxblood seedcoat color supported the hypothesis that the Oxb gene (linked with Am and derived from M0169) with Sal v expresses oxblood seedcoat color. The gene symbol Am is proposed for the gene from M0169 that with Sal v expresses two pleiotropic effects: changes salmon red to scarlet flower color and eliminates the VP of salmon red. The interaction of Sal with Am for flower color and VP expression is discussed for all gene combinations.

The inheritance of corona and hilum ring color of common bean (Phaseolus vulgaris L.) was investigated in the reciprocal cross `Wagenaar' (a Canario market class dry bean) × `Mayocoba' (Mayocoba market class dry bean), where both parents were known to have seedcoat color genotype P [C r] gy J g b v ^lae Rk. `Wagenaar' has greenish yellow (GY) seedcoat (due to gy) except for purple (dark) corona (due to v <sup>lae</sup>) and reddish brown hilum ring (due to J), whereas `Mayocoba' has an entirely GY seedcoat. Seeds produced on the F₁ progeny plants had GY corona and reddish brown hilum ring. The F₂ segregated for three phenotypic classes, the two parental classes and the F₁ class, but the segregation did not fit a 1:2:1 segregation ratio due to disturbed segregation. F₃ progeny tests of 35 randomly selected F₂ parents demonstrated that the two parental classes were true breeding and the F₁ class segregated again (as in the F₂) for the same three phenotypic classes. In spite of variable expressivity of GY color and disturbed segregation, the data support a single gene hypothesis, for which the tentative symbol Chr is proposed. Chr is dominant for changing purple corona to GY, but recessive for changing reddish brown hilum ring to GY. Thus, only one gene, Chr, controls the difference in seedcoat color between the market classes Canario and Mayocoba. An allelism test between Chr and Z (hilum ring color factor) is needed before a formal proposal for Chr can be made.

An inheritance study was conducted with genetic stocks constructed in the genetic background of the recurrent parent 5-593, a Florida dry bean (Phaseolus vulgaris L.) breeding line with black seeds and purple flowers and genotype P T Z l ⁺. The genetic stocks, t ers ers-2 BC₃ 5-593 (pure white seeds), t virgarcus BC₃ 5-593, and t BC₂ 5-593 self-colored were constructed by backcrossing selected recessive alleles for partly colored seedcoats into 5-593. The cross t ers ers-2 BC₃ 5-593 × t BC₂ 5-593 self-colored was studied in F₁, F_2, and F₃. The observed data supported the hypothesis that ers is a synonym for z and that ers-2 is a synonym for a new allele (l ^ers) at the L locus. The cross t ers ers-2 BC₃ 5-593 × t virgarcus BC₃ 5-593 was studied in F₁ and F₂ progeny, and the results confirmed the hypothesis of allelism between ers and z. `Thuringia' (pure white seedcoats) with genotype P t z L was crossed with t ers ers-2 BC<sub>3</sub> 5-593, t virgarcus BC<sub>3</sub> 5-593 and t BC<sub>2</sub> 5-593 self-colored. The cross `Thuringia' (P t z L) × t ers ers-2 BC₃ 5-593 was studied in F₁ and F₂ and supported the hypothesis that l ^ers is an allele at L. The results of the other two test crosses are discussed. The gene ers-2 is a new recessive allele at L, for which the new symbol l ^ers is proposed. Thus, the dominance order at the L locus is L > l ⁺ > l ^ers, where l ⁺ is the null allele at L found in 5-593. The l ⁺ allele does not restrict the colored area of a partly colored seedcoat and is hypothetically the wild-type allele at L.

The red common bean (Phaseolus vulgaris L.) seedcoat colors produced by the dominant gene R and the dark red kidney gene rk ^d are very similar, making it difficult for breeders of red bean varieties to know which genotype is in their materials. A protocol employing test crosses with genetic stocks having known genotypes for seedcoat colors was developed to identify genotypes with either of two very similar dark red seedcoat colors: garnet brown controlled by rk ^d and oxblood controlled by R. Twenty bean varieties and breeding lines were test crossed with genetic tester stocks c ^u BC₃ 5-593 and b v BC₃ 5-593, and four of the varieties were test crossed with [? R] b v BC₃ 5-593. Analysis of the seedcoat colors and patterns in the F₁ progenies from the test crosses demonstrated that unambiguous identification of the genotypes of the two dark red colors could be achieved using the c ^u BC₃ 5-593 and b v BC₃ 5-593 testers. The dark red color (garnet brown) of the Small Red market class materials was demonstrated to be produced by rk ^d, and the dark red color (oxblood) of `Jacobs Cattle' was demonstrated to be produced by R. A Light Red Kidney market class stock was derived from `Redkloud' and used in two crosses: c ^u b v rk BC₁ 5-593 × b v BC₃ 5-593 and c ^u b v rk BC₁ 5-593 × c ^u BC₃ 5-593. Classification of the F₂ progenies demonstrated that the c ^u gene does not entirely prevent rk red color from being modified by V. The interactions of rk, rk ^d, and R with C, c ^u, G, B, and V are discussed, and previous literature concerning those interactions is critically reviewed.