The inheritance of blue pattern flower (BPF) expression was investigated in common bean (Phaseolus vulgaris L.). The BPF trait was derived from accession line G07262, and the flowers express blue banner petal and white wings with blue veins. Crosses between a BPF stock and three other parents, t p mic long micropyle stripe BC3 5–593, t z Fib arcus BC4 5–593, and t Z bip ana Fib marginata BC3 5–593, all segregated in F2 for BPF or white flowers in a 9:7 ratio, respectively. Progeny tests in F3 from two of the crosses supported the hypothesis that two complementary dominant genes control BPF expression and permitted a genetic linkage estimate of cM = 32.4 ± 7.91 map units between p mic and one of the two genes for BPF. A cross between t z fib virgarcus BC3 5–593 and T Prp i-2 V BC2 5–593 demonstrated that t Prp i-2 did not express BPF. Two crosses, T Prp i-2 V BC2 5–593 t p mic BC3 5–593 and 5–593 × a BPF stock, segregated in F2 for plants expressing BPF in a 3/16 frequency. The combined data demonstrated that a new gene, t bp (bp = blue pattern), interacts with Prp i-2 to express BPF and that P is linked with Prp i-2 by 32 map units. The dominance order at the T locus is T > t bp > t. The pedigree source of the t bp gene and the heterogeneity of PI 632736 (t p mic long micropyle stripe BC3 5–593) are discussed.
Mark J. Bassett and Phillip N. Miklas
Mark J. Bassett and Phillip N. Miklas
‘Painted Lady’ (Phaseolus coccineus L.) has bicolor flowers with vermilion banner petal and white wing petals. This flower color pattern is not known in common bean (P. vulgaris L.). The bicolor trait was backcrossed into common bean and its inheritance investigated, including allelism tests with other genes in common bean (T, P, and V) for flower color or pattern and brown seed coat. A pure line (line 33) with bicolor flower and dark olive brown seed coat was crossed to line 5-593 (no flower pattern and black seed coat). Data from the F2 and F3 progenies from that cross demonstrated that a single recessive gene controlled both the bicolor flower and dark olive brown seed coat by pleiotropic gene action. Allelism tests between the bicolor trait (line 179c) and standard genetic tester stocks involving the T, P, V, and Wb (white banner) genes for flower color or seed coat color demonstrated independence of bicolor from those genes and further supported the hypothesis of pleiotropic action on flower and seed coat. Also, the Wb gene was demonstrated to be independent of T and P. The gene symbol bic is proposed for the bicolor gene.
Mark J. Bassett, Colleen Shearon and Phil McClean
Inheritance of two phenotypes, the virgarcus pattern of partly colored seedcoats and the margo d seedcoat pattern, were studied in common bean (Phaseolus vulgaris L.) materials that segregated jointly for genes controlling the two phenotypes to test the hypothesis of allelism of two genes, D and Z. The F2 progeny from the cross j margo BC3 5-593 × t z virgarcus BC3 5-593 produced an unexpected phenotypic class, margo d, suggesting possible allelism of D and Z. The F2 also produced another unexpected phenotypic class, white seedcoat, for which the genetic hypothesis t j z was made. The F2 from the cross t j marginata BC3 5-593 × t z virgarcus BC3 5-593 provided supporting evidence for the new genotype, t j z, for a white seedcoat. Analysis of the F2 and F3 progenies of 80 random F2 plants from the cross t z virgarcus BC3 5-593 × d j (margo d) BC3 5-593 provided support for the hypothesis that the D and Z loci are allelic. Production of two different phenotypes (white vs. white with two tiny pale gray dots, one each at the raphe and micropyle) for t J/j z in two different genetic and cytoplasmic backgrounds is discussed. The F2 from the crosses d j (margo d) BC2 5-593 × j v margo BC2 5-593 and d j (margo d) BC3 5-593 × j margo BC3 5-593 segregated for d (vs. D) phenotypes, which were found not to be independent of a randomly amplified polymorphic DNA (RAPD) marker (AM10560) associated (1.4 cM) with the Z locus. Because the Z gene symbol has priority, we propose to retain Z for the locus.
Mark J. Bassett, Kirk Hartel and Phil McClean
Inheritance of Anasazi pattern of partly colored seedcoats in common bean (Phaseolus vulgaris L.) was studied in a genetic stock t ana B V Anasazi BC3 5-593, whose Anasazi pattern is derived from Plant Introduction (PI) 451802. Line 5-593 is a determinate, Florida dry bean breeding line (with small black seeds) used as the recurrent parent in the development of many genetic stocks. The F2 from the cross t ana B V Anasazi BC3 5-593 × t z virgarcus BC3 5-593 segregated for two nonparental phenotypic classes and was consistent with the hypothesis that a single recessive gene, with tentative symbol ana, produces the Anasazi pattern with t Z ana and a new partly colored pattern Anabip with t z ana. Thus, the Anasazi factor is not an allele at the Z locus. Analysis of 57 random F3 progenies from the cross t ana B V Anasazi BC3 5-593 × t z virgarcus BC3 5-593 supported a genetic model where: 1) with t Z the Anasazi phenotype is controlled by a single recessive gene ana, i.e., genotype t Z ana, 2) the Anabip phenotype has the genotype t z ana, and 3) t Z/z ana produces a restricted Anasazi pattern. The allelism test cross t z ana Anabip BC3 5-593 × t z l ers white BC3 5-593 produced complementation in the F2, demonstrating nonallelism of Ana (actually Bip) with the L locus. The allelism test cross t z ana Anabip BC3 5-593 × t z bip bipunctata BC3 5-593 failed to show complementation in F1 and F2, demonstrating allelism of Ana with the Bip locus. Using bulk segregant analysis, molecular markers linked in coupling to the Ana (OM9200, 5.4 cM) and Bip (OJ17700, 6.0 cM) genes were discovered. Allelism was also suggested by the result that the same linkage distance and recombination pattern were observed when the Ana marker was used to score the bipunctata population. We propose the gene symbol bip ana for the recessive allele at the Bip locus that produces Anasazi pattern with genotype t Z bip ana and the Anabip pattern with genotype t z bip ana. Although bip ana and bip are both recessive to Bip, their interactions with the Z locus are extraordinarily different. The pattern restrictive power of bip ana expresses partly colored pattern with t Z, whereas bip requires t z to express partly colored pattern.
Mark J. Bassett and Phillip N. Miklas
Among light red and dark red kidney common bean (Phaseolus vulgaris L.) varieties, pink seedcoat color (light red kidney) is dominant to dark red, but when Red Mexican varieties (with dark red seedcoats) are crossed with dark red kidney varieties, dark red seedcoat is dominant to the pink segregants observed in an F2 population. A genetic investigation of this reversal of dominance was performed by making crosses in all combinations among standard varieties of the four recessive-red market classes—Light Red Kidney `California Early Light Red Kidney', Pink `Sutter Pink', Red Mexican `NW 63', and Dark Red Kidney `Montcalm'—and observing segregation for seedcoat colors in F2 and F3 progenies. The data were consistent with the hypothesis that `NW 63' carries a new allele at Rk, viz., rk cd, where cd stands for convertible dark red kidney. Thus, C rk cd expresses dark red kidney seedcoats and c u rk cd expresses pink seedcoats. Also, C B rk cd expresses garnet brown seedcoats, whereas C B rk d expresses liver brown seedcoat color. Thus, we propose the gene symbol rk cd for the Rk locus gene in `NW 63'. The rk gene from Light Red Kidney `Redkloud' and `Sutter Pink' was backcrossed (with c u b v) into the recurrent parent 5-593, a Florida dry bean breeding line with seedcoat genotype P [C r] J G B V Rk. In the F2 progenies of BC2 to 5-593, the c u b v rk segregants from `Redkloud' gave true pink seedcoats, whereas those derived from `Sutter Pink' gave consistently very weak pink color under humid Florida growing conditions. We propose the gene symbol rk p, where p stands for pale pink, for the distinctive rk allele in `Sutter Pink'. The more general implications of the above findings were discussed.
George J. Hochmuth, Jeffrey K. Brecht and Mark J. Bassett
Potassium (K) is required for successful carrot (Daucus carota) production on sandy soils of the southeastern United States, yet there is little published research documenting most current university Cooperative Extension Service recommendations. Soil test methods for K in carrot production have not been rigorously validated. Excessive fertilization sometimes is practiced by carrot growers to compensate for potential losses of K from leaching and because some growers believe that high rates of fertilization may improve vegetable quality. Carrots were grown in three plantings during the winter of 1994-95 in Gainesville, Fla., to test the effects of K fertilization on carrot yield and quality on a sandy soil testing medium (38 ppm) in Mehlich-1 soil-test K. Large-size carrot yield was increased linearly with K fertilization. Yields of U.S. No. 1 grade carrots and total marketable carrots were not affected by K fertilization. K fertilizer was not required on this soil even though the University of Florida Cooperative Extension Service recommendation was for 84 lb/acre K. Neither soluble sugar nor carotenoid concentrations in carrot roots were affected by K fertilization. The current K recommendation for carrots grown on sandy soils testing 38 ppm Mehlich-1 K could be reduced and still maintain maximum carrot yield and root quality.
George J. Hochmuth, Jeffrey K. Brecht and Mark J. Bassett
Nitrogen is required for successful carrot production on sandy soils of the southeastern United States, yet carrot growers often apply N in amounts exceeding university recommendations. Excessive fertilization is practiced to compensate for losses of N from leaching and because some growers believe that high rates of fertilization improve vegetable quality. Carrots (Daucus carota L.) were grown in three plantings during Winter 1994–95 in Gainesville, Fla., to test the effects of N fertilization on yield and quality. Yield increased with N fertilization but the effect of N rate depended on planting date; 150 kg·ha–1 N maximized yield for November and December plantings but 180 kg·ha–1 N was sufficient for the January planting. Concentration of total alcohol-soluble sugar was maximized at 45 mg·g–1 fresh root with 140 kg·ha–1 N for `Choctaw' carrots, whereas sugar concentration of `Scarlet Nantes' roots was not affected by N fertilization. Carrot root carotenoid concentration was maximized at 55 mg·kg–1 fresh root tissue with 160 kg·ha–1 N. Generally, those N fertilization rates that maximized carrot root yield also maximized carrot quality as determined by sugar and carotenoid concentrations.
Clifford W. Beninger, George L. Hosfield and Mark J. Bassett
Three dry bean (Phaseolus vulgaris L.) genotypes differing in seedcoat color, mineral brown (P C D J G B v), yellow brown (P C D J G b v), and pale greenish yellow (P C D J g b v), were analyzed phytochemically. Kaempferol 3-O-β-d-glucoside (astragalin) was isolated and identified by nuclear magnetic resonance spectroscopy from all three genotypes, and was the main flavonoid monomer present. Flavonoid polymers (condensed tannins) were detected by thin layer chromatography, but anthocyanins were not detected in the three genotypes. High pressure liquid chromatography analyses indicated that astragalin was present at similar concentrations in pale greenish yellow and mineral brown genotypes, but was significantly lower in yellow brown. Presently, we do not know the functions of the G and B color genes, although the presence of astragalin in the three genotypes studied indicates these genes do not appear to act in a qualitative manner with regard to astragalin production, but may control the amount of astragalin present. Subtle differences in color between these genotypes may be due to the amount and type of tannins which have secondarily polymerized with phenolics and flavonoid monomers.
Mark J. Bassett, Xue Lin-Bao and L. Curtis Hannah
Inheritance of red flower color was investigated in crosses using Lamprecht's lines M0169 and M0056, which are derived from Phaseolus coccineus L., and Univ. of Florida P. vulgaris L. breeding line 5-593. Based on segregation in the F2populations from 5-593 × M0169 and 5-593 × M0056, we hypothesize that the genotypes for flower colors are sal/sal V/V for 5-593 and Sal/Sal v/v for M0169 and M0056. The backcross 5-593 × F, (5-593 × M0056) segregated for four flower colors in about equal frequencies, and F2, F3, and F4progeny tests of the backcross plants provided confirmation of all the genotypes in the digenic model. The two recombinant true-breeding colors/genotypes were white (sal/sal v/v) and china rose (Sal/Sal V/V). We hypothesize that the large deficiency of plants carrying the Sal allele in segregating populations is due to a gametophyte factor linked to Sal. We propose the gene symbol Ga for the gametophyte factor locus, which achieves complete selection for pollen carrying Ga on female plants carrying Ga, i.e., no pollen carrying ga achieves fertilization. The linkage between Ga and the marker locus Sal is 17 CM (centiMorgan).
Mark J. Bassett, Rian Lee, Carla Otto and Phillip E. McClean
Inheritance of the strong greenish-yellow (SGY) seedcoat color in `Wagenaar' common bean (Phaseolus vulgaris L.) was investigated. Line 5-593 is a determinate, Florida dry bean breeding line (with small black seeds) used as the recurrent parent in the development of many genetic stocks, e.g., g b v BC3 5-593. Through crosses with genetic tester stocks, the seedcoat genotype of `Wagenaar' was confirmed to be C J g b v lae Rk. Three randomly amplified polymorphic DNA markers (OAP7850, OAP31400, and OU14950) that cosegregated with the G seedcoat color locus were developed from the F2 population derived from the cross g b v BC2 5-593 × G b v BC3 5-593. From the cross `Wagenaar' × g b v BC3 5-593, 80 F2 plants were classified into 54 non-SGY and 16 SGY seedcoat color plants. When the OAP7850 marker was applied to that population, linkage was not observed with the non-SGY and SGY phenotypes. Conversely, a molecular marker (OAP12400, that was developed from the F2 from the cross `Wagenaar' × g b v BC3 5-593) linked to the locus controlling the SGY phenotype segregated independently of the G locus. Therefore, SGY phenotype is not controlled by the G locus. An F3 progeny test of 76 F2 plants from the cross `Wagenaar' × g b v BC3 5-593 confirmed the hypothesis that a single recessive gene (for which we propose the symbol gy) controls the seedcoat color change from pale greenish yellow (PGY) to SGY. Through crosses with genetic tester stocks, the seedcoat genotype of `Enola' was determined to be C J g b v lae Rk. The test cross `Enola' × `Wagenaar' demonstrated that `Enola' also carries the gy gene. The relationship of `Enola' to the `Mayocoba' market class of common bean and to `Azufrado Peruano 87' is discussed.