Search Results

You are looking at 11 - 20 of 77 items for :

Clear All

Vitamin C (VC) levels (mg/l00 g FW) were determined in 10 varieties of colored bell pepper grown under different field conditions. VC was determined by the microfluorometric method. `Orobelle' (169 mg), `King Arthur' (143 mg), `Valencia' (141 mg), and `Chocolate Bell' (134 mg) had significantly higher VC levels than `Dove' (109 mg), `Ivory' (106 mg), `Blue Jay' (93 mg), `Canary' (90 mg), and `Black Bird' (65 mg). The largest variability (53 mg) in VC levels were observed for varieties that had the highest VC content. Mean VC levels were 143a, 143a, 141a, 136a, 108ab, 93bc, and 63c for the yellow, red, orange, brown, white, purple, and black colors, respectively. Since the Recommended Daily Allowance (RDA) for VC is 60 mg per day, these results suggested that a 100-g serving of fresh bell pepper or less would supply 100% RDA of VC. Therefore, after selecting a color, growers still have the freedom to grow a variety that performs well in their area to produce peppers of high VC contents.

Free access

Blackleaf (a.k.a. chocolate leaf) is of worldwide concern in Vitis due to its negative impact on fruit ripening, yield reduction and overall stress on grapevines. Research suggests blackleaf is induced by high levels of UV radiation and overall light intensity, which induce color changes (purple-brown-black) in exposed leaves, resulting in >50% reduction in photosynthesis. The ability to detect blackleaf symptoms before expression can provide insight into metabolic stresses and the possibility of the use and/or timing of management practices to reduce its impact. Remotely sensed imagery and spatial analysis may elucidate reflectance-related processes and symptoms not apparent to the un-aided eye. In this research we mapped canopy growth (leaves/shoot and shoots/vine), metabolic triggers (photosynthesis, leaf water potential, soil moisture), and percent blackleaf expression within vineyards using global positioning system (GPS), infrared gas analyzer, and digital remotely-sensed images. Each image and data record was stored as an attribute associated with specific vine location within a geographical information system (GIS). Spatial maps were created from the GIS coverages to graphically present the progression of blackleaf across vineyards throughout the season. Analysis included summary statistics such as minimum, maximum, and variation of green reflectance, within a vineyard by image capture date. Additionally, geostatistics were used to model the degree of similarity between blackleaf values as a function of their spatial location. Continuing research will be aimed at identifying spectral characteristics of early season stresses due to UV light, water stress, and reduced photosynthetic capacity. Spatial relationships between early season stress and later blackleaf expression will be assessed using joint spatial dependence measures. Overall, information obtained through digital image and spatial analysis will supplement site level information for growers.

Free access

Theobroma cacao L. (cacao) is a major tropical crop, grown for its oil-rich seed, which is used in the manufacture of chocolate, its derivatives, and cosmetics. Cacao is cultivated mainly by smallholders and represents a significant export commodity for some developing countries such as Côte d’Ivoire. It is conventionally propagated by seeds, grafting, and cuttings. Somatic embryogenesis offers an alternative method for propagation where large-scale production of planting materials is possible. In the current study, the effect of different concentrations of 2, 4-dichlorophenoxyacetic acid (2, 4-D) and kinetin on induction of somatic embryogenesis and plantlet regeneration in two cocoa clones (coded as C1 and C14) were evaluated. Flowers were collected early in the morning, sterilized, explants excised and cultured on Driver, and Kuniyuki Walnut (DKW) media supplemented with different concentrations of 2, 4-D (9, 10, and 20 µM) and kinetin (0.5, 1, 2.5, 5, 10, and 25 µM) in separate experiments. The frequently used media in somatic embryogenesis of cacao [DKW supplemented with 0.022 µM thidiazuron (TDZ) and 9 µM 2, 4-D] was used as a control. The results of the study showed that explants cultured on media supplemented with 10 µM 2, 4-D and 5 µM kinetin produced the highest (28.0 ± 1.1) mean number of embryos/explant in C1 and this was a 9-fold increase in the number of embryos compared with the control. Explants cultured on media supplemented with 10 µM 2, 4-D and 2.5 µM kinetin produced the highest (7.0 ± 4.0) mean number of embryos/explant in C14 whereas the explants cultured on media supplemented with 20 µM 2, 4-D and 2.5 µM kinetin gave the highest (22.0 ± 1.7) mean number of embryos in clone C1 and C14. The regenerated embryos were germinated and successfully weaned in the green house with a survival rate of 70% being recorded. The paper describes an improved protocol compared with previous work in terms of embryo recovery and survival rate of the elite clones of cocoa through somatic embryogenesis. The results of the current study confirm that somatic embryogenesis of cacao clones is genotype dependent.

Free access

habits. New leaves of several other cultivars such as ‘White Chocolate’, ‘Rhapsody in Pink’, ‘Burgundy Cotton’, and ‘Pink Velour’ initially display high levels of dark leaf pigmentation that fade away with maturity and summer heat. Our Ebony selections

Free access

. In Xining (Qinghai, China), in Jul 2011, the high-yield, red chocolate spot faba bean germplasm Tongcanxian 8 was used as the female parent to perform compound crosses with the aforementioned F 1 plants. In Sep 2011, the recrossed F 1 was obtained

Open Access

replications, each containing two experimental trees per treatment and evaluated during 4 years of production, 1994 to 1997, when trees were 3 to 6 years old. Organoleptic evaluation of 65% cacao-containing chocolate samples from the highest yielding clones was

Free access

almost completely desiccated cool-season turf. Similar hybrid bermudagrass cover (50% to 60%) was established by these two methods and by application of herbicide. Finding Tasty, High-yield Cacao Varieties Just Got Easier A 70% cacao, dark chocolate bar

Full access

sold in local and export markets, and the pods are harvested year-round providing a ready source of cash income. There is a growing demand for cacao products. The U.S. chocolate industry alone generated $19.5 billion in sales of chocolate products in

Free access

the chocolate made from these pods, they acknowledged that a link to flavor and pollen donor was needed but was outside the scope of their study. The only previous works attempting to link flavor to pollen donor effects in cocoa were that of

Free access

efficiency, and similar pellicle removal ratings. The kernel quality is suitable for use in chocolate products and baked goods and is competitive with imported Turkish kernels. Origin ‘Yamhill’, tested as OSU 542.102, resulted from a cross of OSU 296.082 × VR

Free access