The β-carotene and total carotenoid content of either fresh or dried tissue of fruits of a total of 57 cultivars of six Capsicum species were analyzed using high performance liquid chromatography (HPLC). β-Carotene levels in ripe fruit varied from 0 to 166 μg·g-1 fresh weight, and carotenoid levels were from 1 to 896 μg·g-1 in ripe fruit in 1996. The range of values for β-carotene was similar in 1997, but that for total carotenoids was wider (4 to 1173 μg·g-1 fresh weight). Fresh fruit of the cultivars Greenleaf Tabasco, Pulla, Guajillo, NuMex Conquistador, Ring-O-Fire, and Thai Dragon contained greater amounts of β-carotene per 100 g fresh weight than the recommended dietary allowance (RDA) for vitamin A for the average adult. For dried Capsicum entries, New Mexican, aji, pasilla, and ancho types had the highest levels of β-carotene. In 1996, β-carotene levels among the dried Capsicum germplasm ranged from 2 to 739 μg·g-1 dry weight, and carotenoid levels from 111 to 6226 μg·g-1. Values were higher in 1997, ranging from 24 to 1198 μg·g-1 dry weight for β-carotene and from 187 to 10,121 μg·g-1 for total carotenoids. A pasilla type (C. annuum L.) had the highest total carotenoid content among the dried entries in both years.
Marisa M. Wall, Cynthia A. Waddell, and Paul W. Bosland
Marisa Wall, Cynthia Waddell, Paul Bosland, and Stephanie Walker
The β-carotene and total carotenoid content of different Capsicum fruit types and species were analyzed using HPLC. This information is useful for breeding high carotenoid chiles (New Mexican type) for the food industry, and also provides nutritional data for the range of fruit types within the Capsicum genus. Fresh fruit from 25 accessions and dried fruit from 39 accessions were evaluated in 1996 and 1997. β-carotene levels varied from 0 to 16.6 mg/100 g fresh weight, and carotenoid levels were from 0.1 to 89.6 mg/100 g in red ripe fruit in 1996. The range of values for β-carotene was similar in 1997, but a wider range in total carotenoids (0.4 to 117.3 mg/100 g fresh weight) was observed. Fresh fruit (100 g) of the cultivars `Greenleaf Tabasco', `Pulla', `Guajillo', `NuMex Conquistador', `Ring-O-Fire', and `Thai Dragon' contained greater amounts of β-carotene than the RDA for vitamin A for the average adult. For dried Capsicum entries, New Mexican, aji, pasilla, ancho, and guajillo types had the highest levels of β-carotene. In 1996, β-carotene levels among the dried Capsicum germplasm ranged from 0 to 739.2 μg/g dry weight, and carotenoid levels were from 21.3 to 6,225.9 μg/g. Values were higher in 1997, and ranged from 23.7 to 1,198.1 μg/g dry weight for β-carotene and from 76.9 to 10,120.6 μg/g for total carotenoids. A pasilla type (C. annuum) had the highest total carotenoid content among the dried entries in both years.
Dean A. Kopsell, David E. Kopsell, Mark G. Lefsrud, Joanne Curran-Celentano, and Laura E. Dukach
Green leafy vegetables are important sources of dietary carotenoids, and members of Brassica oleracea L. var. acephala rank highest for reported levels of lutein and β-carotene. Twenty-three leafy B. oleracea cultigens were field grown under similar fertility over two separate years and evaluated for leaf lutein and β-carotene accumulation. Choice of B. oleracea cultigen and year significantly affected carotenoid levels. Lutein concentrations ranged from a high of 13.43 mg per 100 g fresh weight (FW) for B. oleracea var. acephala `Toscano' to a low of 4.84 mg/100 g FW for B. oleracea var. acephala 343-93G1. β-carotene accumulations ranged from a high of 10.00 mg/100 g FW for B. oleracea var. acephala `Toscano' to a low of 3.82 mg/100 g FW for B. oleracea var. acephala 30343-93G1. Carotenoid concentrations were significantly higher in year 2 than in year 1, but rank order among the cultigens for both lutein and ß-carotene did not change between the years. During each year, there were high correlations between leaf carotenoid and chlorophyll pigments. Under similar growing conditions, choice of B. oleracea cultigen will influence carotenoid accumulation, and this may affect the health benefits of consuming these leafy green vegetable crops.
Keiko Ishikawa, Shiho Sasaki, Hiroshi Matsufuji, and Osamu Nunomura
In order to evaluate the advantages of parthenocarpy in the breeding of Capsicum, we investigated the percentage of fruit set after emasculation or excision of styles, fruit size, and amounts of ß-carotene, capsaicinoids, and ascorbic acids of the seedless fruits of Capsicum annuum L. `Shishiroh' no. 562. Seedless fruits were induced from ≈80% of flower buds after emasculation or excision of styles. The levels of ß-carotene (44.07 μg·g-1), capsaicin (1.73 mg·g-1), and dihydrocapsaicin (1.12 mg·g-1) of mature seedless fruits were 10 times higher than those of seeded fruits. The amount of ascorbic acid, however, was at the same level (≈230 mg/100 g). The length of the seedless fruit was ≈50% smaller than that of the seeded fruit at 2 weeks after the flowering and decreased to 44% at mature stage.
John Stommel, Judith A. Abbott, Robert A. Saftner, and Mary J. Camp
Consumer acceptance of fresh and processed tomato (Lycopersicon esculentum Mill.) products is influenced by product appearance, flavor, aroma, and textural properties. Color is a key component that influences a consumer's initial perception of quality. Beta-carotene and lycopene are the principal carotenoids in tomato fruit that impart color. Analytical and sensory analyses of fruit quality constituents were conducted to assess real and perceived differences in fruit quality between orange-pigmented, high-beta-carotene cherry tomato genotypes and conventional lycopene-rich, red-pigmented cherry tomato cultivars. Thirteen sensory attributes were evaluated by untrained consumers under red-masking light conditions where differences in fruit color could not be discerned and then under white light. Panelists preferred the appearance of the red-pigmented cultivars when viewed under white light, but scored many of the other fruit-quality attributes of red- and orange-pigmented genotypes similarly whether they could discern the color or not. Irrespective of light conditions, significant genotype effects were noted for fruit appearance, sweetness, acidity/sourness, bitterness, tomato-like flavor, unpleasant aftertaste, firmness in fingers, juiciness, skin toughness, chewiness, bursting energy, and overall eating quality. Attributes whose scores differed between white and red-masking lights were intensities of tomato aroma, tomato-like flavor, sweetness, bursting energy, juiciness, and overall eating quality. The results demonstrated a color bias favoring red-pigmented fruit and highlight the influence that color has on perception of tomato fruit quality, particularly on tomato-like flavor, juiciness, and overall eating quality. Interactions between fruit chemical constituents likely influenced perceptions of quality. High-beta-carotene genotypes contained higher levels of sugars and soluble solids and equal or higher titratable acidity than the red-pigmented cultivars. Total volatile levels did not differ among genotypes; however, several individual volatiles were significantly higher in high-beta-carotene genotypes.
James M. Bradeen and Philipp Simon
The Y2 locus conditions α- and β-carotene accumulation in the xylem (core) of carrot roots. The dominant allele suppresses carotene, but not xanthophyll accumulation, resulting in yellow-cored roots. Individuals homozygous for the recessive allele are rich in carotenes and are therefore orange-cored. Increased consumer interest in high carotene produce requires improved understanding of carotene biosynthesis and color development and more-efficient breeding techniques. We examined 103 F2 individuals generated from inbred populations differing in core carotene content. Bulked segregant analysis identified AFLP bands putatively linked to Y2. Linkage was confirmed for some bands by mapping. Linked bands were excised from gels, re-amplified, cloned into pGEM vectors, and sequenced. Cloned fragments and sequence information were used to characterize larger genomic regions to identify codominant markers. Currently we are developing codominant, PCR-based markers that can be used to rapidly genotype individuals in breeding programs, to characterize wild, feral, and cultivated populations for diversity and evolution studies, and to examine the role of Y2 in carotene accumulation.
Gene E. Lester, John L. Jifon, and Gordon Rogers
Muskmelonfruit[Cucumis melo L. (Retiulatus Goup)] sugar content is related to potassium (K)-mediated phloem loading and unloading of sucrose into the fruit. During fruit growth and maturation, soil fertility is often inadequate (due to poor root uptake) to satisfy the demand for K. Potassium uptake also competes with the uptake of Ca and Mg, two essential minerals needed for melon fruit membrane structure, function and postharvest shelf-life. Supplemental foliar-applied K could alleviate this problem especially during the critical fruit growth/maturation period. We conducted experiments to determine the effects of timing of supplemental foliar K applications on fruit quality and health attributes of orange-flesh muskmelon `Cruiser'. Plants were grown in a greenhouse and fertilized with a regular soil-applied N–P–K fertilizer throughout the study. Entire plants, including the fruit were sprayed with a solution of a novel glycine amino acid-complexed potassium (Potassium Metalosate, 24% K), diluted to 4.0 mL·L-1, 3 to 5 d after anthesis (fruit set) and up to 3 to 5 d prior to abscission (full-slip). Three sets of plants were either sprayed weekly, or bi-weekly or not sprayed (control). Fruit from plants receiving supplemental foliar K matured on average 2 days earlier, and had significantly higher fruit K concentrations, soluble solids, total sugars, ascorbic acid (vitamin C), beta-carotene, and were firmer than fruit from control plants. In general, there were few differences in fruit quality aspects between bi-weekly or weekly treatments. The data demonstrate that fruit quality and marketability as well as some of the developmentally induced K deficiency effects can be alleviated through foliar nutrition.
Gene E. Lester, John L. Jifon, and Gordon Rogers
Muskmelon [Cucumis melo L. (Reticulatus Group)] fruit sugar content is directly related to potassium (K)-mediated phloem transport of sucrose into the fruit. However, during fruit growth and maturation, soil fertilization alone is often inadequate (due to poor root uptake and competitive uptake inhibition from calcium and magnesium) to satisfy the numerous K-dependent processes, such as photosynthesis, phloem transport, and fruit growth. Experiments were conducted during Spring 2003 and 2004 to determine if supplemental foliar K applications during the fruit growth and maturation period would alleviate this apparent inadequate K availability in orange-flesh muskmelon `Cruiser'. Plants were grown in a greenhouse and fertilized throughout the study with a soil-applied N-P-K fertilizer. Flowers were hand pollinated and only one fruit per plant was allowed to develop. Starting at 3 to 5 days after fruit set, and up to 3 to 5 days prior to fruit maturity (full slip), entire plants, including the fruit, were sprayed with a glycine amino acid-complexed potassium (potassium metalosate, 24% K) solution, diluted to 4.0 mL·L-1. Three sets of plants were sprayed either weekly (once per week), biweekly (once every 2 weeks) or not sprayed (control). Fruit from plants receiving supplemental foliar K matured on average 2 days earlier than those from control plants. In general, there were no differences in fruit maturity or quality aspects between the weekly and biweekly treatments except for fruit sugar and beta-carotene concentrations, which were significantly higher in the weekly compared to the biweekly or control treatments. Supplemental foliar K applications also resulted in significantly firmer fruit with higher K, soluble solids, total sugars, ascorbic acid (vitamin C) and beta-carotene concentrations than fruit from control plants. These results demonstrate that carefully timed foliar K nutrition can alleviate the developmentally induced K deficiency effects on fruit quality and marketability.
Kevin M. Crosby, John L. Jifon, and Daniel I. Leskovar
) support. Under the “Designing Foods for Health” grant (CSREES 2001-34402-10543, 2003-34402-13647), the program has selected, for genetically enhanced levels of beneficial phytochemicals such as β-carotene as well as total sugars within TAES, commercially