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Jung Hyun Kwon, Ji Hae Jun, Eun Young Nam, Kyeong Ho Chung, Ik Koo Yoon, Seok Kyu Yun, and Sung Jong Kim

Being self-incompatible, most Asian plums should be planted with a compatible pollinizer to produce fruits. Therefore, the selection of an adequate pollinizer is essential when new plum cultivars are released. To select a suitable pollinizer for ‘Summer Fantasia’ plum, the S genotype, cross-compatibility, pollen viability, and flowering time of five candidate cultivars were evaluated. Using polymerase chain reaction (PCR) analysis, the S genotype of ‘Summer Fantasia’ was determined as S a S c, which was expected to be compatible with other S genotypes. To test cross-compatibility, the trees were covered with caging net to prevent unintended pollination, and pistils were hand pollinated without emasculation. Fruit set percentage was calculated 10 weeks after pollination. The fruit set percentage resulting from the cross between ‘Summer Fantasia’ and ‘Taiyo’ (S b S c) was 13.8%, whereas that resulting from other combinations was less than 5.0%. Pollen germination percentage was investigated to monitor pollen viability; it varied yearly among cultivars, although ‘Formosa’ (10.6%) and ‘Taiyo’ (13.8%) showed the highest pollen germination percentages among the cultivars. When averaged over three years and two locations, ‘Summer Fantasia’ bloomed 2–3 days after ‘Akihime’, ‘Formosa’, ‘Oishiwase’, and ‘Purple Queen’. Blooming period of ‘Summer Fantasia’ and ‘Taiyo’ overlapped almost entirely. Overall, the results indicated that ‘Taiyo’ was the most suitable pollinizer for ‘Summer Fantasia’.

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Mark J. Bassett

The inheritance of hilum ring color in common bean (Phaseolus vulgaris L.) was investigated using various genetic tester stocks developed by backcrossing recessive alleles into a recurrent parent stock 5-593 with seedcoat genotype P [C r] D J G B V Rk, viz., mar BC2 5-593, mar BC3 5-593, mar v BC2 5-593, mar d BC2 5-593, and mar d BC3 5-593. The current hypothesis is that the margo character is controlled by mar and hilum ring color is controlled by d but expresses only with mar. The V locus controls flower and seedcoat color. The allelism test crosses `Citroen' (P C d j g b v lae) × mar BC3 5-593 and `Citroen' × mar d BC3 5-593 demonstrated that mar is allelic with j and that the putative d in mar d BC3 5-593 is allelic with the d in `Citroen'. Thus, the former genetic tester stocks mar BC3 5-593 and mar d BC3 5-593 are reclassified as j BC3 5-593 and d j BC3 5-593, respectively, because mar is a synonym for j. Similarly, the former genetic tester stock mar v BC2 5-593 is reclassified as j v BC2 5-593. The interaction of j with d expresses as loss of color in the hilum ring. The development of the white-seeded genetic tester stock P c u d j BC3 5-593 was described in detail, where the all-recessive tester `Prakken 75' was used as the source of the recessive alleles. The previously reported work showing that the partly colored seedcoat gene t interacts with mar to control seedcoat pattern is now interpreted to mean that the joker (J) locus interacts with t to produce partly colored seedcoat patterns. The genetic loci D and V were found to segregate independently. The common gene for dull seedcoats (asper, asp) is discussed and contrasted with j.

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Mark J. Bassett

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, F2, 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 BC3 5-593, t virgarcus BC3 5-593 and t BC2 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.

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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.

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Mark J. Bassett and Phillip N. Miklas

transferred from P . coccineus to common bean by interspecific crossing. Although wb was reported ( Bassett, 1993 ) to be nonallelic with V and Blu , additional test crosses are needed to preclude the possibility that wb is a new allele at either T

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Mark J. Bassett and Phillip N. Miklas

were planted in the field in 2001 at Gainesville, FL. Segregation data for flower color and pattern were recorded. Test crosses with genetic stocks having arcus or marginata pattern seedcoats. In 2003 a BC 3 -F 3 progeny from the double

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James L. Brewbaker

based on testcrosses with bite tests in the field at 18 to 20 d after pollination. Test-cross parents varied but always involved the inbred now designated Hi82, our most senior inbred and one with below-average tenderness. Undesirable flavors and

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Luisa Santamaria, Emmalea G. Ernest, Nancy F. Gregory, and Thomas A. Evans

from ‘Jackson Wonder’ (susceptible) × B2C (F resistant) were screened. From the E-resistant by E-resistant test cross ‘Dover Tucker’ × ‘Cypress’, 223 F 2 plants were screened. The F 2 seeds were planted in 10-cm pots in seed starter substrate and

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Zhanao Deng, Fahrettin Goktepe, and Brent K. Harbaugh

are homozygous. Therefore, they could serve as parents for test crosses for an inheritance study of leaf spots. Table 2. Segregation for leaf spots in progeny of 18 caladium crosses (crosses made in 2004; progeny phenotyped in 2006

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Zhanao Deng and Brent K. Harbaugh

that these cultivars were homozygous-recessive for leaf blotching and might be good parents for test crosses. Five test crosses were made to test the segregation of leaf blotching in ‘White Christmas’. It was used as a seed parent in two crosses and as