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Greg Schlick and David Bubenheim

Chenopodium quinoa is being considered as a “new” crop for Contolled Ecological Life Support Systems(CELSS) due to the unique protein composition and high mineral values of the seeds and leaves. Quinoa is known to have very high protein levels (12-185 reported from field trials), with desirable amino acid proportions, and mineral concentrations suitable for a balanced human diet. Contolled environment, hydroponic culture has increased the nutritional value and has the potential of increasing the yield. Protein and mineral values have increased substantially and will be discussed in more depth. The high concentration of protein, unique amino acid profile, high mineral values, versatility in preparation and the potential for increased yields make quinoa a useful crop for CELSS and long-term space missions

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Mohanjeet S. Brar, Jameel M. Al-Khayri, Teddy E. Morelock, and Edwin J. Anderson

Cowpea (Vigna unguiculata L.) is an important grain legume, which in developing countries provides much of the protein in human diets. A plant regeneration system for cowpea was developed. Cotyledons were initiated on MS medium containing 15 to 35 mg·L-1 benzylaminopurine (BAP) for 5 to 15 days. For shoot regeneration, the explants were transferred to a medium containing 1 mg·L-1 BAP. Regeneration percentage (1% to 11%) and the number of shoots (4 to 12 shoots per explant) were significantly influenced by genotype. The duration of culturing and BAP concentration in the initiation stage significantly affected the regeneration capacity. Explants initiated on 15 mg·L-1 BAP for 5 days resulted in the highest regeneration percentage. Conversely, the highest number of shoots was obtained from explants initiated on 35 mg·L-1 BAP. This is the first report of plant regeneration of U.S. cowpea cultivars.

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Gary Thompson, Russel Tronstad, and Michael Kilby

During the last two decades, per capita consumption of fresh fruit has increased markedly. Although many believe that this increase has been caused by a heightened concern in health and diet, economic analyses indicates that changes in retail prices and increasing per capita incomes adequately explain the increased consumption of fresh fruit. Also, with more single households and women entering the labor force, the convenience factor of focal preparation has likely caused an increase in the consumption of fresh fruit. Substantial substitution between fresh fruit products has occurred: grapes and strawberries have increasingly substituted for citrus fruit, particularly grapefruit. These results suggest that relative prices for fresh fruits, increasing disposable income, and the changing demographic composition of households have prompted observed increases in the per capita consumption of fresh fruit.

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Leslie A. Weston and M.M. Barth

Vegetables provide a major source of essential vitamins such as ascorbic acid and beta carotene and other quality components in the human diet. Postharvest yield and quality of vegetables depend upon genetic, biotic, edaphic, chemic and other factors, as well as combinations of these factors. Successful production, quality and nutritional value of vegetables are related to both primary and secondary metabolic processes occurring during vegetable growth and development. Related research has focused upon cultivar selection, cultural practices used during production, interaction of light and temperature, and use of chemicals for growth regulation, and pest control. We will discuss the effects of genetic, pest, and soil management; crop maturity at harvest; environmental modification; and climatic conditions. Postharvest vegetable quality will be characterized in terms of vitamin content, appearance, yield, and flavor.

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Borut Bohanec, Marijana Jakše, Predrag Šesek, and Michael J. Havey

Bulbous leek-like plants are a poorly defined group usually assigned to the Allium ampeloprasum complex. Studies were initiated to determine the origin of an unusual bulbous accession received in Shanxi province in China, where it was used in diet as garlic but propagated by seeds, and to genetically compare this accession with morphologically similar plants from Europe. Genetic analyses included karyotypes and genomic in situ hybridization, pollination to leek, genome size determination and nuclear rDNA and plastid DNA polymorphisms. Results revealed that this agriculturally interesting accession from China is a so far unknown variant within tetraploid A. ampeloprasum cultivated taxa. We also observed that great-headed garlic did not share derived states in the chloroplast with leek, revealing that this cultivated plant does not possess the cytoplasm of leek or garlic, while its 1C genome size was 17% bigger than those of studied leek and bulbous-leek accessions.

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R.C. Herner, M. Uebersax, E. Kabelka, and R. Mazzucchelli

We present the decision case titled “One Size Does Not Fit All” developed for use in a capstone experience in the College of Agriculture and Natural Resources. The decision case requires an oral and written presentation of a solution to a problem posed in the case. Students work in small groups comprised of students with many majors within the college. The case study is based on the recent NRC report titled “Pesticides in the Diets of Infants and Children,” and the perceptions of the public concerning pesticides, baby food, and children. We outline how this case study was developed, the support material supplied to the students, and the experiences and observations that we have made as a result of using this case study. In addition, we outline how this case study could be modified to address other questions related to pesticides and food safety in a classroom setting.

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D.A. Smith, M.L. Metz, and S.L. Cuppett

Dry edible beans (Phaseolis vulgaris) represent an inexpensive way to incorporate protein into the diet as a food ingredient, but beans contain unpleasant flavors and several anti-nutritional factors that limit their use without first processing with long heat treatments. `Great Northern' bean flour was processed using either static or specially designed dynamic (continuous) processing methods. The dynamic process treated flour slurries at temperatures up to 124°for 20 sec. The slurries were quick-frozen and freeze-dried after frozen storage periods of 0, 8, 24, 120, or 504 hr. The flours were analyzed for sensory properties, emulsifying activity, foaming properties, and trypsin inhibition. The heat treatments improved sensory attributes of the flour. The foam capacity and foam stability decreased in heat-treated flours. Trypsin inhibitor activity was at a minimum level immediately following thermal processing, but increased with time in frozen storage prior to drying. Minimal thermal processes cannot be relied upon to inactivate trypsin inhibitors.

Open access

G. G. Kennedy and W. R. Henderson

Abstract

A laboratory procedure for assaying Lycopersicon spp. for resistance to the tobacco hornworm Manduca sexta (L.) is described. Results from this procedure, which employed excised foliage from greenhouse grown plants and first instar hornworm larvae from a colony maintained in the laboratory on artificial diet, were similar to those obtained with intact plants, with field collected hornworm larvae, and with field grown resistant plants. The Lycopersicon hirsutum f. glabratum accessions PI 134417 and LA 407 were highly resistant to M. sexta. Resistance was manifest as a significant reduction in larval survival and in weight gained by survivors over a 72 hour period. The interplant variation in larval weight gains within accessions was highly significant, suggesting that most of the accessions tested were segregating for resistance to M. sexta.

Open access

James H. Bredt

Abstract

NASA is interested in extraterrestrial crop production because it is expected that some future missions may require life support systems that can regenerate food as well as air and water. Such systems must produce a nearly complete human diet within very stringent limits on size and energy consumption. Although many problems remain to be solved by further research, CELSS based on crop production by higher plants appear to be feasible. The feasibility of this approach will be tested in the next several years by a project to build and operate a preprototype system that can recycle oxygen, carbon, water, and nitrogen. If this project succeeds, it will be followed by Space Station experiments to develop cultural methods for weightless plants and ground-based tests of more sophisticated prototypes with human occupants. Readiness to build operational space systems may be achieved as early as the turn of the century.

Open access

K. W. Keane

Abstract

Minerals are constant constituents of animal tissue. They may be essential components for the maintenance of life processes, or they may perform some nonessential but favorable function. Man is omniverous and can live on a diet of animal, vegetable or mineral origin. The sources of minerals are therefore immaterial for man and the other omnivora; but the presence of all these elements in our food supply is essential. All essential elements are beneficial when present in the body in proper balance. Out of balance or in deficiency they lead to diseases and in excess they may be toxic. Various mineral elements are so interrelated in metabolism that their quantitative requirements are interdependent. A deficiency of a given nutrient may exist with respect to its specific function and also in the balance which should be maintained between it and certain other essentials. Conversely, pathological changes may result from relative as well as from absolute excesses of a given element.