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using cold-hardy C. japonica and C. oleifera selections. The cold-hardiness of ornamental camellia cultivars and hybrids has been documented in International Camellia Society reports ( https://camellia.iflora.cn/Cutivars/Country ). They are mostly

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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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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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breeding. Recent reports revealed not all grapefruit and pummelo cultivars contain high level of FCs ( Widmer, 2005 ; Widmer and Haun, 2005 ); some selections and low acid mutants have undetectable (read zero) or little amount of the components. Currently

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Abstract

Bruce 12-4 is a plum selection released for breeding purposes that possesses an unusual combination of disease resistance, tree longevity, cold hardiness and other characteristics. The seedling requires chilling of 700 hr of temperature below 7.2°C (45°F). This seedling has consistently produced high yields of fruit in central Alabama (Fig. 1).

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Abstract

A heterogeneous cucumber (Cucumis sativus L.) population (mostly gynoecious) was evaluated at five locations for single-plant fruit yield at the mature-fruit stage in 1981. Seeds from the highest-yielding plants were then harvested, combined, and partitioned into five lots. Seeds were combined such that each location received only the superior genotypes from the other four locations. This procedure was continued for an additional four cycles using two types of selection: single-plant selection for fruit number at the mature-fruit stage (1981–82) and half-sib family selection at the once-over harvest stage (1983–84). In 1985, yield improvement from selection was measured by compositing the seeds of the selected plants or families from each of the four cycles and five locations and planting them at the five locations. No progress was made for total, marketable, or early yield. Percentage of culls was reduced an average of 0.7% per cycle. Genotype by environment interaction among the diverse locations may have prevented progress for yield.

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Realized heritability estimates of bolting percentage, pink root and fusarium basal rot severities and incidences, and percentage of single-centered bulbs were estimated for half-sib families of an intermediate-day, open-pollinated onion (Allium cepa L.) population using selection response analysis. Half-sib families were selected based upon an index that equally weighted bolting percentage, pink root and fusarium basal rot severities and incidences, percentage of single-centered bulbs, and bulb quality. Families were subjected to one cycle of half-sib family recurrent selection. Pink root and fusarium basal rot severity was reduced by 17% and 7%, respectively, with realized heritability estimates of 1.28 and 0.65, respectively. More progress for pink root severity was made than was selected. Disease incidence was reduced by 18% and 12%, respectively, with heritability estimates of 0.65 and 0.60, respectively. Very little progress was made for the percentage of single-centered bulbs and this was reflected in a heritability estimate of 0.17. Selection based upon multiple characters at the same time may reduce the effectiveness of making improvements in a single trait. However even with low to moderate heritability, improvements were made, and suggest that further improvements can be made through selection.

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Narrow-sense heritability and selection response estimates for weevil resistance were higher based on half-sib family means than on individual plants. Resistance levels in available sources are low and evaluation with low weevil numbers is essential for differentiation. Consequently, highest performing families produce multiple plants with no injured roots and separation of resistance levels among those plants is impossible Since a large amount of additive variance is contained among plants within families and early reduction of plant numbers would increase breeding efficiency, a study was conducted to determine the effectiveness of individual plant selection in combination with half-sib families. Two plants were selected from each of the 10 highest families based on weevil resistance and yield. Selected clones were compareds for resistance levels to means of their families when tested over 2 years. Fifty percent of selected clones had higher resistance levels than their family means indicating that individual plant selection was effective. Optimum methods of combining family and individual plant selection will be discussed.

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-used cultivars were ‘Strawberry Festival’ and ‘Florida Radiance’, which occupied ≈60% and 10% of planted acreage, respectively. The UF strawberry breeding program has sought to improve fruit quality attributes over time through phenotypic recurrent selection

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(NTEP), including the 2007 and 2013 National Bermudagrass Tests ( NTEP, 2007 , 2013 ). In addition, three OSU experimental lines were included in this test: OKS 2009-3, OKS 2011-1, and OKS 2011-4. These latter three selections were included because of

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