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The increasing interest in grape and wine production in colder regions of the United States over the past 3 decades has brought consistent progress in the breeding and selection of cold-tolerant, disease-resistant grape cultivars. Among the most

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Two lemon [Citrus limon (L.) Burm.] cultivar selection trials are being conducted at the Yuma Mesa Agriculture Center in Somerton, Ariz. Some selections in these trials include: `Allen Eureka', `Berna', `Cook Eureka', `Cascade Eureka', `Cavers Lisbon', `Strong Lisbon', `Femminello Comune', `Lapithkiotiki', `Limoneira 8A Lisbon', `Limonero Fino 49', `Monroe Lisbon', `Primofiori', `Santa Teresa', `Walker Lisbon', and `Villafranca'. Selections that have had superior yields include `Cascade Eureka', `Cook Eureka', `Strong Lisbon', `Limoneira 8A Lisbon', `Limonero Fino 49', `Primofiori', `Femminello Comune', and `Villafranca'. Fruit size data suggest that `Limonero Fino 49' has consistently good fruit size, and consistently larger fruit than `Limoneira 8A', the industry standard. `Cavers Lisbon' and `Femminello Comune' also have good fruit size. `Lapithkiotiki' also had large fruit size, but its shape was unacceptably elongated. We also found significant differences in peel thickness and juice pH among the selections. `Santa Teresa' had significantly lower juice pH and a thinner peel than some of the other selections under evaluation.

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Thermal degradation of fractions from sweetpotato roots (`Jewel') was conducted with gas chromatographymass spectrometry to identify precursors of critical flavor volatiles. Upon heating (200 C), sweetpotato root material that was insoluble in methanol and methylene chloride produced similar volatile profiles to those from sweetpotatoes baked conventionally. Volatiles derived via thermal degradation of the nonpolar methylene chloride fraction and the polar methanol fraction did not display chromatographic profiles similar to those from conventionally baked sweetpotatoes. Initial reactions in the formation of critical volatiles appear to occur in the methanol and methylene chloride insoluble components. Maltol (3-hydroxy-2-methyl-4-pyrone) was found to be one of the critical components making up the characteristic aroma of baked sweetpotatoes. Integration of an analytical technique for the measurement of flavor into sweetpotato breeding programs could potentially facilitate the selection of improved and/or unique flavor types.

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Height and caliper (age 3 years), and flower count (age 3.5 years) were evaluated for 36 open-pollinated families of Magnolia grandiflora L. outplanted in two genetic tests in Bexar County, Texas. Significant family differences existed for height, caliper, number of flowers per tree, and percent of trees flowering in both tests. Family heritability estimates for all traits ranged from 0.72 to 0.92. Coefficients of genetic prediction (CGP) between growth and flowering characteristics were small but positive; CGP between height and percent of trees flowering was 0.28 and 0.24 in the two tests. Early growth rate and flowering appeared to be under strong genetic control; thus, improvement through selection would be efficient. However, both traits should be evaluated since the genetic relationship between them was weak.

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visual quality rankings, good survival, and limited or lacking fruit production of ‘Gulf Stream’, ‘Jaytee’, and ‘Harbour Dwarf’ warranting wider landscape use of these selections in the Florida landscape. The overall objective of this study was to

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main strategies have been used in fruit breeding programs to overcome these difficulties: 1) the development of early selection criteria to eliminate genotypes with a long juvenile period and 2) the shortening of this period by means of forced growth of

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that are capable of performing well in challenging urban sites, thus making site-specific selection of shrubs absolutely crucial. There is currently a lack of quantitative assessments of stress tolerance in a large proportion of available species and

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Abstract

Man's breeding and selection of woody ornamentals is, by no stretch of the imagination, a novel pursuit, but has employed succeeding generations of plantsmen for many centuries. Currently, selection of woody ornamentals that depends on government or industry funding is inevitably stimulated by cultural or disease problems with existing species or cultivars, by changing consumer needs, or by recognition of a market demand for superior or novel plants. The worth of this work frequently is judged in terms of its potential economic benefit. Speculative breeding and/or selection of esoteric plants, a traditional pursuit of the enthusiastic horticulturist, is now difficult for anyone other than the keen amateur to sustain.

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hobbyists ( Peterson, 1986 , 1991 ). Currently, over 45 cultivars are available from nurseries ( Pomper et al., 2009a ), and many of these selections are maintained at the Kentucky State University (KSU) National Clonal Germplasm Repository (NCGR) for

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both Perovskia selections. Growth data were analyzed to determine lower and upper nutritional limits for each taxa. Plants of both Perovskia selections fertilized with 50 and 75 mg·L −1 N resulted in similar and significantly smaller plants than

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