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1.
The United States is a major producer of many different types of oilseeds, but the predominant one is soybean, that remarkable legume whose meal and oil serve many animal feed, human food, and domestic industrial product needs. More than half of the soybeans and the products produced from them are exported. The 16 mill MT of soy meal processed and fed in the United States in 1981 constituted 88% of the total oilseed meal, 71% of the high-protein feeds, and 48% of total processed feeds. Of the total soy protein available, less than 5% goes into human food products such as meat extenders, simulated meats, baked goods, dairy product analogs, dietary foods, infant foods, and fermented food products. Less than 1% of soy protein in the United States is used in industrial products, mainly as a binder for pigmented paper coatings. Of the total soy oil available, about 95% is consumed in food products such as margarines, salad oils, and cooking oils. About 5% of soy oil is applied to nonfood uses such as alkyd paints, plasticizer/stabilizers for vinyl plastics, soaps, eraser factices, and many other lesser uses. Other major oilseeds produced in the United States include cottonseed, flaxseed, peanut, safflower, and sunflower. Corn oil is produced in significant quantities as a by-product of the corn starch industry. The oilseed crops having the greatest oil productivity are peanut and sunflower. However, sunflower meal has certain deficiencies for feed and food uses. If the United States is to draw upon oilseed crops as significant contributors to feed, food, industrial products, and agricultural fuel needs, greatly improved productivity will be needed either from new oilseed crops or from improved varieties of present commercial crops.  相似文献   

2.
Probable factors influencing resistance to aflatoxin synthesis in soybeans have been investigated by using cultures of Aspergillus parasiticus NRRL 3240. Soybeans contain a small amount of zinc (0.01 mug/g) bound to phytic acid. Autoclaving soybeans at 15 pounds (6803.88 g) for 15 min increases the aflatoxin production, probably by making zinc available. Addition of zinc to both autoclaved and nonautoclaved soybeans promotes aflatoxin production. However, addition of varying levels of phytic acid at a constant concentration of zinc depresses aflatoxin synthesis with an increase in the added phytic acid. In a synthetic medium known to give good yields of aflatoxin, the addition of phytic acid (10 mM) decreases aflatoxin synthesis.  相似文献   

3.
Soybeans are an important crop known to harbour a complex of Diaporthe and Phomopsis species. This complex has been reported to be involved in several soybean diseases, including Phomopsis seed decay. In this study, two species of Diaporthe/Phomopsis fungi from soybean plants were identified by morphological and molecular characterizations. Koch's postulates were confirmed by pathogenicity tests on hypocotyls of soybean seedlings. Phomopsis longicolla was found to be the most common and virulent pathogen to soybeans in Korea. Phomopsis sp., which was considered as a new soybean pathogen, might have been introduced from other plants given that similar strains of Phomopsis sp. have infected fruit trees in China, Japan and Portugal and vegetable plants in the United States.  相似文献   

4.
This Perspective, arising from a workshop held in July 2008 in Buffalo NY, provides an overview of the role NMR has played in the United States Protein Structure Initiative (PSI), and a vision of how NMR will contribute to the forthcoming PSI-Biology program. NMR has contributed in key ways to structure production by the PSI, and new methods have been developed which are impacting the broader protein NMR community.  相似文献   

5.
An intensive regional research campaign was conducted by the North American Carbon Program (NACP) in 2007 to study the carbon cycle of the highly productive agricultural regions of the Midwestern United States. Forty‐five different associated projects were conducted across five US agencies over the course of nearly a decade involving hundreds of researchers. One of the primary objectives of the intensive campaign was to investigate the ability of atmospheric inversion techniques to use highly calibrated CO2 mixing ratio data to estimate CO2 flux over the major croplands of the United States by comparing the results to an inventory of CO2 fluxes. Statistics from densely monitored crop production, consisting primarily of corn and soybeans, provided the backbone of a well studied bottom‐up inventory flux estimate that was used to evaluate the atmospheric inversion results. Estimates were compared to the inventory from three different inversion systems, representing spatial scales varying from high resolution mesoscale (PSU), to continental (CSU) and global (CarbonTracker), coupled to different transport models and optimization techniques. The inversion‐based mean CO2‐C sink estimates were generally slightly larger, 8–20% for PSU, 10–20% for CSU, and 21% for CarbonTracker, but statistically indistinguishable, from the inventory estimate of 135 TgC. While the comparisons show that the MCI region‐wide C sink is robust across inversion system and spatial scale, only the continental and mesoscale inversions were able to reproduce the spatial patterns within the region. In general, the results demonstrate that inversions can recover CO2 fluxes at sub‐regional scales with a relatively high density of CO2 observations and adequate information on atmospheric transport in the region.  相似文献   

6.
Consequential life cycle assessment (CLCA) has emerged as a tool for estimating environmental impacts of changes in product systems that go beyond physical relationships accounted for in attributional LCA (ALCA). This study builds on recent efforts to use more complex economic models for policy‐based CLCA. A partial market equilibrium (PME) model, called the U.S. Forest Products Module (USFPM), is combined with LCA to analyze an energy demand scenario in which wood use increases 400 million cubic meters in the United States for ethanol production. Several types of indirect economic and environmental impacts are identified and estimated using USFPM‐LCA. A key finding is that if wood use for biofuels increases to high levels and mill residue is used for biofuels and replaced by natural gas for heat and power in forest products mills, then the increased greenhouse gas emissions from natural gas could offset reductions obtained by substituting biofuels for gasoline. Such high levels of biofuel demand, however, appear to have relatively low environmental impacts across related forest product sectors.  相似文献   

7.
There are fewer than 162 ha of commercial Chinese chestnut orchards in the United States, with approximately half of these in the Southeast. Large numbers of Chinese chestnut seedlings are planted annually in the United States for home and game food production; however, knowledge about chestnut propagation, fertilization, pests, harvest, storage and marketing is not adequate. There is little commercial marketing of U.S.-grown Chinese chestnuts through roadside markets and local farmers’ markets as the supply is low and unpredictable. However, we yearly import 4.5 mill kg of European chestnuts to satisfy the U.S. market. Successful chestnut orchards will require vegetatively propagated selections, intensive management, mechanical harvesting, and control of insect and disease pests.  相似文献   

8.
During the 20th century, medicine has confronted a series of problems threatening health care delivery in the United States. Historically, crises developed related first to quality of care, later to access and finally to the current issue of cost. Factors responsible for the large increases in health care expenditures in the United States during the last decade include increased medical care costs, population and demand for care. Additionally, economy-wide inflation, advanced medical technologies, an aging population, the growth of health care facilities, expansion of third-party payment systems including Medicare and Medicaid and rising incomes per capita have occurred. Programs now exist, and others are being planned, through which physicians, individually in private practice and collectively through organized medicine, may confront this major challenge now threatening the very foundations of health care delivery in the United States.  相似文献   

9.
Large quantities of diverse and appropriately adapted native plant germplasm are required to facilitate restoration globally, yet shortages can prevent restorations from attaining desired species diversity and structure. An extensive native plant industry has developed in the United States to help meet these demands, yet very little is known about its capacity to support germplasm needs. To better understand current capacity and germplasm availability, we report results of the first comprehensive and quantitative assessment of the native plant industry in the United States, which includes at least 841 vendors nationwide and the species they make available for restoration. We synthesized lists of commercially available species from native plant vendors across the United States and identified gaps in species availability to inform germplasm research, development, and production. Of the approximately 25,000 vascular plant taxa native to the United States, 26% are sold commercially, with growth form, conservation status, distribution, and taxonomy significantly predicting availability. In contrast, only 0.07% of approximately 3,000 native nonvascular taxa are sold commercially. We also investigated how demand for germplasm to support high‐quality restoration efforts is met by vendors in the Midwestern tallgrass prairie region, which has been targeted extensively by restoration efforts for decades. In this well‐developed native plant market, 74% of more than 1,000 target species are commercially available, often from vendors that advertise genetically diverse, locally sourced germplasm. We make recommendations to build on the successes of regional markets like the tallgrass prairie region, and to fill identified gaps, including investing in research to support production, ensuring more consistent and clear demand, and fostering regional collaboration.  相似文献   

10.
Polyamines in soybeans   总被引:2,自引:1,他引:1       下载免费PDF全文
Wang LC 《Plant physiology》1972,50(1):152-156
Putrescine, spermidine, and spermine were three main polyamines isolated from soybeans and partially characterized. Occurrence of polyamines in soybeans was established by separating trichloroacetic acid extracts of soybeans by cationic exchange column chromatography, identification with thin layer chromatography, paper electrophoresis, mass spectral analysis, reactions with ninhydrin and Dragendorff reagents, and spectrophotometric characteristics. Soybeans contained a minimum of 29.0 micrograms of polyamines per gram of full-fat flour. The alcohol-soluble fraction of soybeans contained polyamines also. Resting seeds contained spermidine in higher concentration than either putrescine or spermine. Spermine appeared to be present in lowest concentration. Preliminary experiments suggested that some polyamines were possibly in bound forms.  相似文献   

11.
Biotechnological processes for conversion of corn into ethanol   总被引:2,自引:0,他引:2  
Ethanol has been utilized as a fuel source in the United States since the turn of the century. However, it has repeatedly faced significant commercial viability obstacles relative to petroleum. Renewed interest exists in ethanol as a fuel source today owing to its positive impact on rural America, the environment and United States energy security. Today, most fuel ethanol is produced by either the dry grind or the wet mill process. Current technologies allow for 2.5 gallons (wet mill process) to 2.8 gallons (dry grind process) of ethanol (1 gallon = 3.785 l) per bushel of corn. Valuable co-products, distillers dried grains with solubles (dry grind) and corn gluten meal and feed (wet mill), are also generated in the production of ethanol. While current supplies are generated from both processes, the majority of the growth in the industry is from dry grind plant construction in rural communities across the corn belt. While fuel ethanol production is an energy-efficient process today, additional research is occurring to improve its long-term economic viability. Three of the most significant areas of research are in the production of hybrids with a higher starch content or a higher extractable starch content, in the conversion of the corn kernel fiber fraction to ethanol, and in the identification and development of new and higher-value co-products.  相似文献   

12.
Abstract: Throughout the United States, managers lack safe, effective methods to control expanding populations of the invasive monk parakeet (Myiopsitta monachus). Because the reproductive inhibitor diazacon (20,25 diazacholesterol) has been used effectively in captive monk parakeets, we provided diazacon-treated sunflower seeds to birds at electric utility substations inhabited by parakeets in south Florida, USA. Nest productivity (nestlings plus eggs with embryos) averaged 1.31 (SE = 0.45, n = 100 nests) at 6 treated sites compared to 4.15 (SE = 0.68, n = 50 nests) at 4 untreated sites, a 68.4% reduction. Exposure of native bird species to treated bait was infrequent. Diazacon is an effective means to reduce reproductive success of monk parakeets, and development of methods to limit exposure of nontarget birds will enable more widespread use of this useful population management technique.  相似文献   

13.
On July 25, 1989, President George Bush, in response to reports written by the National Advisory Councils of the National Institute of Neurological Disorders and Stroke and the National Institute of Mental Health and at the urging of Congress, signed a presidential declaration designating the 1990s to be the "Decade of the Brain" and called on the United States to observe the decade with appropriate activities. At mid-decade, scientific accomplishment has been spectacular; however, both public support and increases in research resources have been minimal. It can be anticipated that scientific progress will continue to be impressive for the remainder of the decade, but many research opportunities will either not be addressed or will be postponed. At mid-decade, the time has come to re-evaluate the research agenda and the public strategy for the remainder of the decade.  相似文献   

14.
Soybeans have a wet stigma overtopped by a pellicle that originates from the cuticle. There are numerous exudate-filled, axially oriented channels between cells of the transmitting tissue in the stigma and style. Pollen tubes grow in these channels and receive nutrition and mechanical guidance. Transmitting-tissue cells of the obturator are secretory also, but the obturator in soybean does not appear to control direction of pollen tube growth mechanically. The significant function of transmitting tissue in soybeans is to provide nutrition and to control direction of pollen tube growth.  相似文献   

15.
 The annual sunflower (Helianthus annuus L.) is a morphologically and genetically variable species composed of wild, weedy, and domesticated forms that are used for ornament, oilseed, and edible seeds. In this study, we evaluated genetic variation in 146 germplasm accessions of wild and domesticated sunflowers using allozyme analysis. Results from this survey showed that wild sunflower exhibits geographically structured genetic variation, as samples from the Great Plains region of the central United States were genetically divergent from accessions from California and the southwestern United States. Sunflower populations from the Great Plains harbored greater allelic diversity than did wild sunflower from the western United States. Comparison of genetic variability in wild and domesticated sunflower by principal coordinate analysis showed these groups to be genetically divergent, in large part due to differences in the frequency of common alleles. Neighbor-Joining analyses of domesticated H. annuus, wild H. annuus and two closely related wild species (H. argophyllus T. & G. and H. petiolaris Nutt.) showed that domesticated sunflowers form a genetically coherent group and that wild sunflowers from the Great Plains may include the most likely progenitor of domesticated sunflowers. Received: 2 December 1996/Accepted: 4 April 1997  相似文献   

16.
Limited by the availability of data, conservation planners must use surrogates for biodiversity when selecting conservation areas. Although several methods have been proposed for selecting surrogates, no clear set of species attributes have been described that allow for the efficient a priori selection of surrogate groups. We used a database of 1449 species in two regions of the United States to (1) examine the consistency in the performance of simple taxonomic-based surrogates of biodiversity and (2) test five hypotheses proposed to explain surrogate performance. First, we compared the ability of sites selected to protect members of seven surrogate groups to protect non-surrogate species in the north-western United States and in the Middle-Atlantic region of the eastern United States. Then, in a separate analysis, we tested whether surrogate performance could be explained by (1) taxonomic diversity; (2) nested species distributions; (3) hotspots of biodiversity; (4) species range sizes; (5) environmental diversity. Our first analysis revealed little consistency in the performance of surrogates in the two different study regions. For example, butterflies provided protection for 76% of all other species in the north-western United States but only 56% of all other species in the eastern United States. Our second analysis revealed only weak associations between species characteristics and surrogate performance. Furthermore, these associations proved inadequate for selecting successful surrogates across study regions. Overall, our results suggest that in lieu of searching for optimal surrogate groups, research efforts will be better spent by developing alternative methods for assessing conservation value in areas where data on species distributions are limited.  相似文献   

17.
Nonhuman animal welfare is arguably the most contentious issue facing the hog industry. Animal advocacy groups influence the regulation of hog farms and induce some consumers to demand more humane pork products. Hog producers are understandably reluctant to improve animal well being unless the premium they extract exceeds the corresponding increase in cost. To better understand the relationship between animal welfare and production costs under different farm systems, this study investigates 4 stylized hog production systems. The results show that increasing animal welfare for all hogs in the United States will increase retail pork prices by a maximum of 2% for a small welfare increase and 5% for a large welfare increase. The cost of banning gestation crates measured by this study is lower than the consumer willingness-to-pay from other studies.  相似文献   

18.
Leisure consumption has been increasing in the United States since the 1960s. Over the same period, inactive lifestyles have contributed to adverse health outcomes. We propose a new way of categorizing leisure into groups based on the amount of physical exercise needed. Our results show that physically active leisure is a normal good whose demand rises with education and health, while physically passive leisure is an inferior good whose demand rises with lower education and poorer health. These patterns allow us to propose a taxonomy that categorizes various leisure activities into ‘Active’ and ‘Passive’ groups.  相似文献   

19.
International Paper (IP), the world's largest forest products company, owns the Androscoggin Mill, a large pulp and paper mill in Jay, Maine, in the northeastern United States. This case study describes the transformation of the Androscoggin Mill from an object of public opprobrium and conflict to a show-case for environmental management. In the late 1980s, an 18-month strike had embittered workers and townspeople and left the mill's reputation in tatters. In response to mill environ-mental violations, some of which were considered crimes by state regulators, the town of Jay passed its own environmental ordinance to control mill emissions. Early in the 1990s, new management, including two former corporate-level employ-ees, sought to change the mill's business approach and turn the Androscoggin Mill into IP's best environmental performer. The initial emphasis on establishing and maintaining compliance was expanded to include aggressive pollution prevention efforts that led to cooperative projects with the Maine Department of Environmental Protection, the U.S. Environmental Protection Agency, and stakeholder groups. The mill's ap-proach in the 1990s evolved further to essentially follow prin-ciples of industrial ecology. New approaches focused on "clos-ing the loop" by finding beneficial uses for previously landfilled wastes, replacements for most hazardous chemicals, and re-ductions in solid and hazardous waste generation. The mill also pursued the establishment of symbiotic relationships with a facility that began using a mill by-product on-site and an on-site natural gas burning facility that provided part of the mill's steam demand. IP also established a public advisory committee in 1992 to advise management on operational and "big-picture" issues, which later included the application of sustain-ability criteria to the mill. IP has since formed community advisory committees at each of their integrated pulp and paper mills.  相似文献   

20.
Soy protein and isoflavonoids in soybeans exhibit the improvement of insulin resistance. Our previous IN VITRO study showed that Chungkookjang (CKJ), fermented unsalted soybeans, had better antidiabetic actions than cooked unfermented soybeans (CSB) by increasing isoflavones aglycones and small peptides. We investigated whether 40% fat diets with different protein sources such as CSB, CKJ, and casein modulated peripheral insulin resistance in 90% pancreatectomized (Px) diabetic rats. The Px rats weighing 209+/-14 g were freely provided casein, CSB, or CKJ diets for 8 weeks. Both CKJ and CSB increased whole body glucose disposal rates and glucose uptake into skeletal muscles of Px rats as much as rosiglitazone plus casein treated rats during euglycemic hyperinsulinemic clamp. In addition, CKJ and CSB decreased hepatic glucose output at hyperinsulinemic clamped states, compared to the Casein group. The reduction of hepatic glucose output was greater in CKJ than CSB. This reduction was associated with enhanced tyrosine phosphorylation of IRS2 and serine (473) phosphporylation of Akt, indicating improved hepatic insulin signaling. This improved signaling led to decreased phosphoenolpyruvate carboxykinase expression to reduce hepatic glucose output. In conclusion, fermented soybeans mainly with BACILLUS SUBTILIS improved hepatic insulin sensitivity better than unfermented soybeans by enhancing hepatic insulin signaling cascade in diabetic rats.  相似文献   

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