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Thomas A. Greene

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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Jyh-Bin Sun, Ray F. Severson, William S. Schlotzhauer, and Stanley J. Kays

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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Todd C. Wehner and Christopher S. Cramer

Agricultural Research Service, nor criticism of similar ones not mentioned. We gratefully acknowledge the technical assistance of Rufus R. Horton, Jr., and the advice on recurrent selection methods of Robert H. Moll. The cost of publishing this paper was

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Richard L. Bell

with reduced oviposition as well as increased mortality and delayed development ( Bell, 1991 ; Bell and Puterka, 2004 ; Butt et al., 1988 , 1989 ; Puterka, 1997 ; Robert et al., 1999 ). Observation of breeders’ selections in the orchard suggested

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Heather L. Merk, Shawn C. Yarnes, Allen Van Deynze, Nankui Tong, Naama Menda, Lukas A. Mueller, Martha A. Mutschler, Steven A. Loewen, James R. Myers, and David M. Francis

Breeders of horticultural crops and agronomic crops have often adopted different strategies and systems of selection. Breeders of grain crops have a long tradition of quantitative approaches and of collecting objective data from large populations

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Patrick D. O'Boyle, James D. Kelly, and William W. Kirk

considerable promise for breeding genetic resistance to CBB ( Kelly et al., 2003 ; Miklas et al., 2006 ). Molecular markers allow breeders to avoid direct screening techniques that may be less effective in selection of quantitative traits that are

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Fekadu Fufa Dinssa, Ruth Minja, Thomas Kariuki, Omary Mbwambo, Roland Schafleitner, and Peter Hanson

. Varieties adapted to diverse environments and matching consumer preferences must undergo rigorous evaluation using farmer and consumer participatory approaches in diverse production environments. Farmer participatory plant breeding or variety selection has

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June Liu, Zhimin Yang, Weiling Li, Jingjin Yu, and Bingru Huang

cold tolerance in seashore paspalum through traditional breeding efforts as a result of insufficient genetic variability in cold tolerance or the lack of cold-tolerant cultivated germplasm ( Duncan and Carrow, 1999 ). Somaclonal selection is a powerful

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Robert R. Shortell, Stephen E. Hart, and Stacy A. Bonos

determine the amount of intraspecific variability of Kentucky bluegrass cultivars and experimental selections to sequential applications of bispyribac-sodium herbicide. Materials and Methods This experiment was conducted in 2004 and 2005 at the Rutgers

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Susana Boso Alonso, Virginia Alonso-Villaverde Pilar Gago, José L. Santiago, Mariá C. Martínez, and Emilio Rodriguez

Agricultura Pesca y Alimentación, 1988 ) led to an increasing demand for ‘Albariño’ grapes and to the substitution of low-quality cultivars and the hybrids they produced (then typical of post-Phylloxera Galicia) by ‘Albariño’. Because no clonal selection had