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Jesús Enrique Retes-Manjarrez, Sergio Hernández-Verdugo, Carlos Alfonso López-Orona, Raymundo Medina-López, José Antonio Garzón-Tiznado, and Jesús Enrique Retes-Cázarez

of the target trait to design the best breeding model for introgression of the desirable trait into the cultivated background. The third step is to carry out the plan ( Retes-Manjarrez et al., 2017 ). Pepper may be infected by several viruses. The

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James W. Olmstead, Hilda Patricia Rodríguez Armenta, and Paul M. Lyrene

program ( Lyrene and Brooks, 1995 ). These open-pollinated progeny were tetraploid or near tetraploid and were highly variable, but in general showed morphological variation consistent with introgression of sparkleberry traits, and possessed higher

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Paul M. Lyrene

underdeveloped seeds are found with the good seeds from most highbush × highbush crosses, so those found in the BC 2 were not necessarily the result of V. arboreum introgression. Pollination of flowers on F 1 hybrids with pollen from tetraploid V. arboreum

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Joseph C. Kuhl, Kelly Zarka, Joseph Coombs, William W. Kirk, and David S. Douches

introgression in our food crops. Currently, the NPTII gene is also in the vector construct T-DNA region. Transformation methods exist to create marker-free transgenics in potato ( Rommens et al., 2004 ). Further transformations in our program have created RB

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Reid R. Rice and William F. Tracy

hybrids predominantly derived from the Stiff Stalk and Lancaster genetic backgrounds ( Taller and Bernardo, 2004 ; Tallury and Goodman, 1999 ). Evaluation of the introgression of exotic germplasm in breeding of U.S. dent corn has been conducted in efforts

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John W. Scott

, except in cases in which the breeding material has introgressions from wild species for disease resistance or other genes ( Miller and Tanksley, 1990 ; Williams and St. Clair, 1993 ). Genomic databases are being developed at increasingly rapid rates, and

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Fuad Gasi, Silvio Simon, Naris Pojskic, Mirsad Kurtovic, Ivan Pejic, Mekjell Meland, and Clive Kaiser

dendrogram. A large number of the mentioned accessions formed clusters exclusively with traditional B&H reference cultivars, whereas a slightly smaller number grouped very tightly with international reference cultivars indicating introgression of foreign

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Martha A. Mutschler, Jian Hua Xiong, Ahmed Wally, and Ricardo Lobato-Ortiz

The wild tomato Lycopersicon pennellii is resistant to numerous important pests of cultivated tomato, L. esculentum, including armyworm, fruitworm, aphids, leafminers, and whitefly. The pest resistance of L. pennellii is mediated by the presence of acylsugars, which constitute 90% of L. pennelliitype IV trichome exudate. Transfer of the ability to accumulate acylsugars could result in pest-resistant tomato cultivars, and thus, a reduction in the dependence on synthetic chemicals for insect control for this crop. Initial tomato lines bred for acylsugar production possessed the desired insect resistance, but were of poor horticultural quality due to linkage drag. These tomato lines possessed seven or eight L. pennellii introgressions, some of which were quite large. As a result, about 25% to 30% of the genomes of these acylsugar lines were comprised of L. pennellii DNA. A set of 20 molecular markers was created, providing markers throughout each introgression. The acylsugar breeding program then combined use of a biochemical assay for acylsugars and genomic analyses using these molecular markers to determine which of the introgressions were involved in the linkage drag, and to select plants that either eliminated or shortened those introgressions. Introgressions on chromosomes 2, 3, 5, and 10 were found to be associated with negative characteristics, such as delayed germination, reduced fruit set or size, delayed maturity, or reduced seed set. New acylsugar lines that eliminate or reduce some of these introgressions were created. The new lines show marked improvement in some of the affected traits, while also producing acylsugars. Hybrids created using these lines show marked improvement in horticultural type.

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Paul M. Lyrene

moved to the greenhouse for use as parents in 2017 began to flower, several were discarded because they lacked clear signs of V. stamineum introgression (flowers resembled highbush flowers, lack of pubescence on leaf petioles and new growth flushes

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Jennifer Johnson-Cicalese, James J. Polashock, Josh A. Honig, Jennifer Vaiciunas, Daniel L. Ward, and Nicholi Vorsa

introgression and pyramiding in genetically productive backgrounds should provide future genetic gain for FRR and crop productivity. Literature Cited Bruederle, L.P. Hugan, M.S. Dignan, J.M. Vorsa, N. 1996 Genetic variation in natural populations of the large