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Zoltán Pék, Lajos Helyes and Andrea Lugasi

high levels of antioxidants ( Abushita et al., 2000 ), which are important in the prevention of many cancer types and cardiovascular diseases ( Takeoka et al., 2001 ). Color is one of the most important quality components of tomato fruits. The amount of

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C. Larrigaudiere, E. Pinto and M. Vendrell

The differential effects of two color improving products, ethephon an ethylene-releasing compound, and seniphos, a nonethylene-releasing product, were studied on `Starking Delicious' apples (Malus domestica Borkh L.). Ethephon and seniphos were applied 2 or 3 weeks before commercial harvest. Ethephon- and seniphos-treated fruit showed a significant improvement of peel color associated with a sharp increase in anthocyanin content and chromaticity values. Color improvement in ethephon-treated apples occurred during the preharvest period and cold storage. The seniphos-treated fruit stopped color development in cold conditions. In comparison to the ethephon-treated fruit, the seniphos-treated apples showed lower internal ethylene concentrations and a ripening delay. Both treatments sharply increased the activity of phenylalanine-ammonia-lyase enzyme, which seemed to be the determining factor of color enhancement. The seniphos-treated apples compared to ethephon had higher fruit firmness and lower soluble solids concentrations. Anthocyanin biosynthesis may be enhanced by seniphos treatment without inducing ethylene production or other ripening associated changes. As a consequence, fruit treated with seniphos can be held longer in storage.

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John McCallum, Gail Timmerman-Vaughan, Tonya Frew and Adrian Russell

Developmental, environmental, and genetic factors affecting seed color were studied in the progeny of a cross between two white-flowered (aa) green cotyledon (ii) field peas (Pisum sativum L.): the pale large-seeded Marrowfat cultivar Primo and the greener small-seeded Prussian Blue OSU442-15. Changes in chlorophyll and carotenoid content during seed development of the parental genotypes were determined by high performance liquid chromatography analysis. Both cultivars accumulated similar pigment quantities per seed, but pigment loss was greater during maturation of `Primo'. Bleached and unbleached mature seed tissues also were compared for pigment composition. Lutein was the predominant pigment in bleached cotyledons of both cultivars. Only trace amounts of pheophytins were detected in unbleached seed. In both genotypes, chlorophyll A : B ratios were ≈1:1 in seed coats compared to 3:1 in cotyledons. Objective measurements of seed color in terms of luminance (lightness) and chrominance (hue and saturation) were made in YUV color space by video image analysis. Inheritance of seed color was studied in an F2 population derived from the `Primo' × `OSU442-15' cross and inbred descendants. Quantitative trait loci (QTL) for seed color were localized by interval mapping using a linkage map of 199 molecular markers spanning most of the genome and by bulked segregant analysis and selective genotyping. Four genomic regions affecting seed color were detected. A major gene accounting for 61% of the phenotypic variance in seed lightness (Y luminance component) was identified on linkage group V linked to r locus. Another major gene, which accounted for 56% of the phenotypic variance in seed hue (U chrominance component), was mapped to a linkage group containing group III and IV markers. A QTL with smaller effect on seed hue (U and V chrominance components) was detected on linkage group VII. Support for overdominant allelic interaction for a QTL on linkage group I, adjacent to the legumin locus Lg-J, was obtained by selective genotyping of the seed lightness distributional extremes.

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Kathleen M. Kelley, Bridget K. Behe, John A. Biernbaum and Kenneth L. Poff

Two surveys were conducted to determine characteristics important in containerized edible flowers that could be sold in retail outlets. Self-selected participants at Bloomfest at Cobo Hall, Detroit, were assigned to one group that rated the importance of attributes such as color of pansy (Viola ×wittrockiana Gams. `Accord Banner Clear Mixture'), color combinations, container size, and price. Participants assigned to a second group rated color, color combinations, and container size. Flower color was allocated the most points in the purchasing decision (63% for the first group and 95% for the second), with a mixture of all three colors (blue, yellow, and orange) being the most desirable. Responses were subjected to Cluster Analysis (SPSS Inc., Chicago), which resulted in the formation of three distinct groups. The groups were labeled “Likely Buyer” (those who had eaten and purchased edible flowers before and rated characteristics of edible flowers favorably); “Unlikely Consumer” (those who had eaten edible flowers before and had rated characteristics of edible flowers unfavorably); and “Persuadable Garnishers” (those who had not eaten edible flowers before, but were very likely to purchase edible flowers for a meal's garnish).

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Irene Kadzere, Chris B. Watkins, Ian A. Merwin, Festus K. Akinnifesi, John D. K. Saka and Jarret Mhango

The full commercial potential of wild loquat [Uapaca kirkiana (Muell. Arg.)], a fruit that is widely used for food and income in parts of Africa, is restricted by its short shelf life and variability in postharvest quality. We have evaluated within and among tree variability in fruit size and color at harvest, and changes of color, soluble solids concentrations (SSC) and pulp deterioration during storage, of fruit harvested during the maturation period. The relationships between fruit shape, size, seed number and SSC of fruit harvested at the ripe stage of maturity was also assessed. Size and color of fruit within and among trees at harvest varied greatly within the same location on the same harvest date. The a* values (redness) were more variable than for other color attributes, reflecting a range of fruit colors from greenish to brown. During a 6 day storage period, fruit color lightness and yellowness decreased, while redness increased, and variation in color attributes decreased. Although fruit color intensified during storage, the SSC of fruit after ripening was linked more with fruit color at harvest, with mean concentrations ranging from 6.7% to 13.8% among trees. When fruit were harvested four weeks later and categorized by color at harvest, SSC varied from 11.8% in greenish-yellow fruit to 14.5% in browner fruit. Pulp deterioration of stored fruit harvested unripe was observed by 6 days. The SSC of fruit harvested when ripe was not significantly correlated with shape, size or seed number. These observations have important implications for germplasm selection and collection of U. kirkiana for domestication purposes. Timing of harvest and/or postharvest sorting of fruit is likely to reduce variability in SSC during the postharvest period.

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Jessica D. Lubell and Mark H. Brand

Elepidote rhododendrons are important landscape plants because of showy flowers and bold evergreen foliage. The most common flower colors are lavender, pink, and white, but red flower color is highly sought after. Only some elepidote rhododendrons

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Rosanna Freyre, Chad Uzdevenes, Liwei Gu and Kenneth H. Quesenberry

carotenoid pigments and are inferred to serve to attract pollinators ( Davies, 2004 ). Flavonoids are the most common flower color pigment, and the predominant flavonoid pigments are the anthocyanins. Anthocyanins are composed of an anthocyanidin and sugar

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Andrea Quintana, Rosanna Freyre, Thomas M. Davis and Robert J. Griesbach

cultivars of Anagallis in the ‘Wildcat’™ series with blue, orange, dark orange, and red flower colors. Genes involved in the anthocyanin pathway that are responsible for flower color variation have been widely studied, mostly in Petunia and

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Lingli Lou and Todd C. Wehner

yellowish white or yellowish green ( Porter, 1937 ). The stripes of watermelon can be characterized by stripe width (narrow, medium, or wide), stripe color, and background color (dark green, medium green, or light green). Since the stripe patterns are

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Greg McCollum and Pilar Maul

to oranges, neither ethylene nor 1-MCP had significant effect on color change in ‘Oroblanco’ a pummelo × grapefruit hybrid ( Porat et al., 2001 ). Treatment with 1-MCP will also inhibit ethylene-induced abscission in citrus ( Sisler et al., 1999