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Martina Göttingerová, Michal Kumšta, and Tomáš Nečas

Earth is a plant-oriented planet and horticulture plants have special importance. Horticulture plants add value to Earth’s diversity and are fundamental to all life. Fruit, leaves, stems, roots, flowers, and seeds of horticulture plants include high

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Attila Ombódi, Noémi Koczka, Andrea Lugasi, Hussein Gehad Daood, Mária Berki, and Lajos Helyes

), and occasionally irrigation can reduce dry matter content in onions ( Pejic et al., 2011 ). Water supply effects on the nutritive value of onions raised from sets have not been investigated in detail. Therefore, the objective of this study was to

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Geoffrey Meru and Cecilia McGregor

, oleochemicals, lubricants, pharmaceuticals, and cosmetics ( Jarret and Levy, 2012 ; Panthee et al., 2006 ). To improve the nutritive value of watermelon seed and establish watermelon as a potential oil crop, it is critical to understand the genetic factors

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J.B. Magee

The origins, demise and current status of some common misconceptions about the role of fruit and vegetables in human nutrition are discussed. Most, but not all, of the misconceptions were held by the public. The early widespread belief that tomatoes were poisonous was gradually overcome, and today the tomato is one of the most versatile and widely used foods in the diet. Recent reports suggest that consumption of tomatoes and tomato products has the potential to reduce the risk of certain cancers. Our current awareness of the potential of spinach in nutrition and health evolved from an early misconception that its only important nutritive value was as a source of iron. The connection between foods from the nightshade family and arthritis and the connection of cherries and gout relief are discussed briefly. The misconception that a wide variety of fruit and vegetables was not needed in the human diet was rejected long ago. Today fruit and vegetables are considered essential for their intrinsic nutritive value and for their potential health functionality because of the phytochemicals they contain.

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Jennifer L. Waters and Stephen R. King

Carotenoids are important phytochemical components of our diet and have gained recent attention as important nutritive compounds found mainly in fruits and vegetables with red, orange, and yellow hues. Lycopene is often cited as being inversely correlated with the occurrence of various cancers, in lowering rates of cardiovascular disease, and improving other various other immune responses. Antioxidant activity, specifically oxidative radical quenching power, is the putative rationale for carotenoids' involvement in disease risk reduction. It is unlikely, however, that carotenoid content and antioxidant capacity are directly correlated in the whole food since there are other antioxidants present in watermelon, such as various free amino acids. A total measure of antioxidant potential may prove to be a useful tool for measuring watermelon nutritional value and implementing pursuant breeding goals. One assay that has gained recent popularity is the oxygen radical absorbance capacity (ORAC) assay. ORAC includes two assays that separate lipophylic and hydrophilic antioxidants. Currently, most ORAC protocols use isolated compounds or freeze-dried fruit or vegetable samples. Here, the application of a standard hexane-type extraction method, which is more amenable to whole food carotenoid-containing samples, was investigated as a candidate extraction method for the ORAC assay. Variants of this method as well as of the standard ORAC extraction were compared for extraction efficiency. Finally, ORAC values were correlated with carotenoid content and shown to hold a loose negative correlation. Possible reasons for this are considered and discussed.

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James B. Magee

Many concepts of the nutritional value of fruit and vegetables generally accepted in the past, in the light of more knowledge, today are considered “misconceptions.” For example, the tomato, once considered poisonous, then shown edible, later proved to be a “good” food and a valuable source of minerals and vitamin C, today shows the potential for significant anti-cancer activity. Results of a 6-year study of the dietary habits of 47,000 men reported up to a 45% reduction in the incidence of prostate cancer of those who ate 10 or more servings per week of tomato-based products. Other misconceptions to be discussed include nightshade vegetables and arthritis, apples after meals to clean the teeth and gums, and “if a little is good for you, a lot must be better.” Today's nutritional ideas about many fruits and vegetables may become tomorrow's misconceptions as our knowledge of the composition (e.g., phytochemicals) of fruits and vegetables increases. Examples of this are include the use of muscadine pomace and the nutritive value of strawberries.

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Thomas C. Koch* and Irwin L. Goldman

Carotenoids (provitamin A) and tocopherols (vitamin E) are powerful antioxidants in plants and in the human diet. Carrot (Daucus carota) has been selected for increased levels of carotenoids, contributing to its orange color and reported health benefits. Selection for increased tocopherol has shown success in seed oils, but little progress has been made in the edible portions of most vegetable crops. HPLC measurement following a simultaneous heptane extraction of both compounds has shown a significant (P ≤ 0.001) positive correlation of α-tocopherol with α-carotene (r = 0.65) and β-carotene (r = 0.52). To increase both the tocopherols and carotenoids in plants, 3 populations have been established from select open-pollinated varieties grown in 2002. These populations consist of half-sib families with these differing selection schemes: based strictly on increased α-tocopherol levels; an index to increase α-carotene, β-carotene and α-tocopherol; and a random population in which no selection is occurring. After one cycle of selection, populations were grown on muck soil during the summer of 2003. Compared with the random population, an increase of 24.68% in α-tocopherol concentration was recorded for the population selected strictly on α-tocopherol while increases of 8.47% in α-tocopherol, 9.31% in α-carotene and 7.31% in β-carotene were recorded for the population with index selection. The continuation of these carrot populations shows promise to produce carrot germplasm with improved human nutritive value.

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John R. Stommel* and Robert J. Griesbach

Anthocyanins contribute to color development in economically important vegetables, fruits and floral crops. Their expression is critical to product sensory quality attributes, potential nutritive value, and stress response. Anthocyanins are synthesized in response to numerous environmental factors including temperature and light stress and pathogen attack. We have developed several Capsicum lines, including `02C27', expressing anthocyanin pigmentation differentially in various tissues (leaf, stem, fruit and flower). HPLC analysis demonstrated that the anthocyanins within the fruit, flower and leaves of Capsicum `02C27' were identical and that the major anthocyanidin was a delphinidin glycoside. Line `02C27' exhibits anthocyanin foliar pigmentation that is accumulated differentially in response to temperature stress. Under unfavorable low temperature (20 °C day/18 °C night), mature Capsicum leaves contained 4.6 times less anthocyanin per gram fresh weight than under high (30 °C day/28 °C; day/night) temperatures. Besides containing less anthocyanin in mature leaves, young immature leaves did not develop color as quickly under the lower temperature. Utilizing cloned and sequenced gene fragments of pepper chalcone synthase (CHS), dihydroflavonol 4-reductase (DFR), and anthocyanidin synthase (ANS), we evaluated the role of transcription in regulation of flavonol biosynthesis. Analysis of anthocyanin composition and gene expression data indicated that the block in anthocyanin formation in less pigmented leaves occurred at anthocyanin synthase. In contrast to wild tupe plants, this mutant also exhibited reduced flowering and failed to set fruit under high temperature, long day conditions.

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Prem Nath and Sundari Velu

Among the vegetables, the cucurbitaceous crops form one of the largest groups with their wide adaptation from arid climates to the humid tropics. In Asia, about 23 edible major and minor cucurbits are grown and consumed. Though the data on cucurbits alone are not easily available, the production of watermelon was reported to be 69.7 million tons in Asia, 9.0 million tons in the Near East, 2.7 million tons in North and Central America, and 2.4 million tons in Latin America and the Caribbean (2003). Cucurbits demonstrate wide adaptability, which allows the crops to grow in varied agroclimatic conditions. Among food crops, cucurbits are the largest producers of biological water and are easily digestible. The cucurbits contain 80% to 95% water and also contain nutritive elements, such as carbohydrates, protein, vitamins A and C, calcium, lycopene, phosphorus, potassium, and other properties, in addition to medicinal values. They are common crops in rural, urban, and peri-urban areas, and are accessible to both rich and poor. Even with the gradual increase in production and consumption, the production of cucurbits is plagued by the occurrence of diseases and insect pests, inadequate availability of quality seeds, lack of maintenance of genetic varieties and of naturally occurring biodiversities, and the lack of knowledge on the international standard of quality production and postharvest handling. The thrust areas of development, as identified, are: harnessing new sciences; diversification in cropping patterns; utilization of available genetic diversities; reversal of postharvest losses; and value addition in food products. Cucurbits hold promise as supplementary food for the common masses.

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Jun Gu Lee*, Jong Nam Lee, Eung Ho Lee, and Byoung Yil Lee

Lowbush blueberry (Vaccinium angustifolium Ait.) have some potential agricultural benefits for soil covering and high nutritive antioxidant fruit production in highland of South Korea. As a preliminary research step to introduce and to rapidly propagate the lowbush blueberry in South Korea, we evaluated the cutting propagation efficiency under several cutting conditions. The pH of peatmoss media were adjusted to five target values of 4.5, 5.0, 5.5, 6.0, and control with air-slaked lime. Peat-moss were mixed with perlite at five levels of volume ratios in separate experimental design. The cuttings were also prepared with the three cutting regions from mother stock shoots and the number of nodes per cutting. The rooting of V. angustifolium cuttings initiated at 50 days after cutting in nursery bed, and at 70 days after cutting, shallow root ball were developed by 0.5 cm diameter. The rooting rate and root ball development were favorable in the pH 4.5 and nonadjusted control (pH 4.15) while the mixed ratio of perlite did not affect on rooting efficiency ranging from 30% to 50% mixed treatment. Terminal and intermediate region from newly developed shoot performed higher cutting efficiency compared to the basal region, and four to six nodes per each cutting showed favorable shoot growth and root ball development compared to the 2-node cutting. Thus the cutting of upper shoot region having four to six nodes in acidic peatmoss nursery containing 30% to 50% perlite might be suitable preliminary screened conditions. The cutting propagation efficiency of the five lowbush blueberry clones were also evaluated depending on the summer and early spring cutting.