The use of a new, inexpensive scanning reflectometer, the Colortron, as a field and laboratory colorimeter is investigated. The results obtained from a series of color swatches and from a variety of fruit samples are compared with those obtained from other commercially available, but more expensive, colorimeters (Hunter and Minolta). The Colortron is shown to be very good for gathering and analyzing data. The results of all three instruments were extremely close when measuring color swatches, but the Colortron gave aberrant results with certain fruit having translucent skin and flesh. Despite this caveat, it still has considerable potential for the measurement of fruit color in the field and laboratory.
Oficial de la Unión Europea, 2005 ). Even with adequate size, poor fruit color is an important factor that can result in downgrading fruit and is generally associated with poor visual appearance and low consumer acceptance. Although red color does not
be the least prone to YS. It is also important to know if there is a general trend for higher SSC to be associated with green shoulder vs. u and/or other fruit color genotypes as this would suggest a breeding shift back to u + to attain better
A series of sweet cherry (Prunus avium L.) crosses using yellow-fruited cultivars homozygous recessive for fruit color as tester parents segregated in simple Mendelian ratios for dark fruit and blushed yellow fruit. No evidence was found for the presence of modifier genes.
Fruit of Tabasco pepper (Capsicum frutescens L.) were graded into six color classes, ranging from green to red, as determined by the Munsell System of Color Notation. Color of either whole or mashed Tabasco fruit was measured by use of a Gardner Color Difference Meter, and by the approved method of the Assn. of Official Analytical Chemists (AOAC). Different procedures using the color difference meter were initially analyzed and procedure se analyzed statistically for differences. Analysis of pepper fruit mash using the L-Scale aL/bL value and three optical sample beaker rotations resulted in the smallest se of tested procedures. One hundred percent and 64.8% of fruit color values recorded from the Gardner Color Difference Meter and the AOAC method, respectively, were correctly color-classified by discriminant analysis.
The effect of K fertigation through buried drip irrigation on processing tomato (Lycopersicon esculentum Mill.) was evaluated in two California field trials in 2004, and soil K dynamics was investigated in greenhouse trials. Fertigation trials were conducted in fields with exchangeable soil K of 190 (site 1) and 270 mg·kg-1 (site 2), above the yield response threshold by traditional preplant or sidedress K application established by prior research. Two fertigation strategies were compared to an unfertilized control: continuous fertigation at 100 mg·L-1 K from early fruit set through early fruit color development, and weekly application of 40 kg·ha-1 K over the same period. In both treatments, a total of 200 kg·ha-1 K (from KCl) was applied. K fertigation significantly increased fruit yield at site 2, and improved fruit color at both sites. In the greenhouse experiments, fescue (Festuca arundinacea) was grown for 2 weeks atop columns of eight soils ranging from 120–380 mg·kg-1 exchangeable K; the columns were wetted from the bottom, by capillarity. The fescue roots were separated from the soil by a nylon fabric that prevented root penetration while allowing the penetration of root hairs, creating a two-dimensional root/soil interface. In all soils, fescue K uptake reduced soil exchangeable K only in the top 2 mm of the columns, suggesting that effective K diffusion was very limited. In columns of 200-mm height, applying 100 mg·kg-1 K in the water used to wet the soil had minimal impact on fescue K uptake. In columns of 15-mm height, this method of K application more than doubled fescue K uptake in all soils, suggesting that the effective limit of K movement was between 15-200 mm.
Red and yellow mature fruit color in Capsicum pubescens is controlled by a single gene with yellow (y) recessive to red (y +).
Significant differences in fruit color were created with fruit cluster thinning (20, 40, and 60 clusters/vine), cluster shading (full sun as control, 55% shading, and 95% shading using shading cage constructed of shade cloth), and defoliation (3, 6, 9, 12, and 15 leaves/cluster). Fruit cluster shading and defoliation treatments decreased red fruit color (characterized by Hunte Color a). Fruit cluster thinning increased red fruit color. Anthocyanin profile of Reliance grape was characterized as cyaninidin-3-glucoside and delphinidin-3-glucoside using Paper Chromatography and Thin Layer Chromatography. Analyses of total anthocyanin content (pH shift method), individual anthocyanin and soluble carbohydrates content (High Performance Liquid Chromatography), are being conducted to determine effects of carbohydrate allocation to fruit and sun light on fruit color of Reliance grapes.
Fruit color and carotenoid composition are important traits in watermelon. Watermelon fruit color inheritance has revealed that several genes are involved in color determination. Carotenoids are known to have various functions in plants and animals, such as providing antioxidant activity and other health benefits for humans, and UV protection and pigmentation for plants. Differential gene activity in the carotenoid biosynthetic pathway may result in different color determination of mature fruit. Eight genes encoding enzymes involved in the pathway were isolated and their structures were characterized. While obtaining full-length cDNA of these enzymes, two single-nucleotide polymorphisms were detected in a coding region of lycopene β-cyclase (LCYB). These SNP markers showed cosegregation with red and canary yellow fruit color based on the genotyping of two segregating populations. This will lead to development of a codominant molecular marker for the selection of LCYB allele, which may allow breeders to distinguish between red and canary yellow watermelon fruit colors at the seedling stage.
Fruit of TAMU breeding line 830397 are green in contrast to the cream or orange fruit of commercial cultivars at the mature-seed stage (MS-S). Inheritance of this trait for green MS-S fruit color in Cucumis sativus was investigated. A new locus, gn, is proposed as well as the elimination of the C locus. MS-S fruit color is controlled by two major genes, R and Gn. Fruit is orange when the genotype is R_ _ and green when the genotype is rrgngn. The cream MS-S fruit color trait is incompletely dominant over green, as the genotype rrGnGn is cream while rrGngn produces mature fruit from cream to intermediate in color between cream-colored and green fruit. Spine color is pleiotropic with or very tightly linked to the R locus, but heavy netting from PI 165509 appears not to be linked with the orange genotype and is polygenic.