The environment can affect the intensity of flower color in Eustoma grandiflorum. Low light and alkaline pH within the growing cell can lead to reduced color intensity. Two independent causes are responsible for the decrease in the intensity of flower color. 1) Older flowers were more alkaline than freshly opened flowers. A 7% increase in pH was related with a 10% reduction in color intensity. 2) Flowers that open under low light were paler than those opening under high light intensity. A 25% decrease in light intensity was related to a 30% reduction in the concentration of anthocyanin and a 40% reduction in color intensity.
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
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
Jason D. Lattier and Ryan N. Contreras
winterhardiness, range of flower colors, and unique flower phenotypes, including single-flowered and double-flowered forms ( Contreras and Lattier, 2014 ). Breeders have noted the potential for improvement in althea due to their range of flower color and form and
Jessica G. Barb, Dennis J. Werner and Robert J. Griesbach
Flavonoids, carotenoids, and betalains are three classes of pigments that produce flower color in plants. Of these pigments, flavonoids are the most abundant and responsible for a broad range of flower colors, including pale yellow, ivory, pink
Soon O. Park, Dermot P. Coyne, Nedim Mutlu, Geunhwa Jung and James R. Steadman
Common bacterial blight, incited by Xanthomonas campestris pv. phaseoli (Xcp) is a serious disease of common bean (Phaseolus vulgaris L.). Randomly amplified polymorphic DNA (RAPD) markers and flower color (V gene) previously were reported to be associated with six quantitative trait loci (QTL) affecting leaf and pod resistance to Xcp. However, the markers for the QTL were not confirmed in different populations and environments to indicate their merit in breeding. The objective was to determine if the associations of RAPD markers and the V gene with QTL for leaf and pod resistance to Xcp in a recombinant inbred (RI) backcross population from the cross BC2F6 `PC-50' × XAN-159 and for leaf resistance to Xcp in an F2 population from a different cross pinto `Chase' × XAN-159 could be confirmed. One or two genes from XAN-159 controlled leaf and pod resistance to Xcp. Among six QTL previously detected, five in the RI backcross population and three in the F2 population were confirmed to be associated with resistance to Xcp. The V gene and RAPD marker BC437.1050 on linkage group 5 were most consistently associated with leaf and pod resistance to two to five Xcp strains in the RI backcross population and with leaf resistance to two Xcp strains in the F2 population. One to three QTL affecting leaf and pod resistance to Xcp accounted for 22% to 61% of the phenotypic variation. Gene number (one to two) estimations and number of QTL (one to three) detected for leaf and pod resistance to Xcp in the RI backcross population were generally in agreement. The marker BC437.1050 and V gene, along with other resistance genes from other germplasm, could be utilized to pyramid the different genes into a susceptible or partially resistant bean line or cultivar to enhance the level of resistance to Xcp.
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
Jianjun Li, Xiaoya Lian, Chenglin Ye and Lan Wang
, Mexico, Australia, New Zealand, and the United States ( Shang et al., 2011 ). The color is considered to be an important indicator in measuring ornamental value and offers a basis for plant classification ( Zhang et al., 2012 ). The flower color is
Cecil Pounders, Tim Rinehart, Ned Edwards and Patricia Knight
now available that vary in ultimate size, growth habit, pest tolerance, and flower color to service various landscape objectives ( Knox, 2000 ). Breeding of crapemyrtle in the United States was primarily pioneered by Otto Spring of Okmulgee, OK, who
Meredith R. Blumthal, L. Art Spomer, Daniel F. Warnock and Raymond A. Cloyd
Flower color preference of western flower thrips [WFT (Frankliniella occidentalis) (Thysanoptera: Thripidae)] was assessed by observing insect location after introduction into chambers containing four different colored flowers of each of three plant species: transvaal daisy (Gerbera jamesonii), matsumoto aster (Callistephus chinensis), and chrysanthemum (Dendranthema ×grandiflorum). Preference was based on the number of WFT adults found on each flower 72 hours after infestation. Significantly higher numbers of WFT were found on yellow transvaal daisy and yellow chrysanthemum. When these accessions were compared in a subsequent experiment, WFT displayed a significant greater preference for the yellow transvaal daisy. Visible and near infrared reflectance spectra of the flowers used in the study were measured to determine the presence of distinct spectral features that would account for the relative attractiveness of the flowers. Likewise, the reflectance spectra of three commercially available sticky cards (blue, yellow, and yellow with a grid pattern) that are used to trap or sample for WFT were compared to those of the flowers to determine any shared spectral features that would support observed WFT flower color preference. The observed similarity between the yellow transvaal daisy and yellow sticky card reflectance spectra supports the hypothesis that flower color contributes to attractiveness of WFT. In particular, the wavelengths corresponding to green-yellow (500 to 600 nm) seem to be responsible for attracting WFT. These findings also indicate that yellow sticky cards may be more appropriate in sampling for WFT than blue sticky cards. Although further research is needed, under the conditions of this study, yellow transvaal daisy appears to be a potentially useful trap crop for WFT.