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71.
A bioeconomic simulation model for Lates calcarifer predicted that a strategy involving crossing current generation males with previous generation females would be a practical, effective and profitable way of dealing with protandry when batch rearing for selective breeding to improve the growth rate. The strategy allowed earlier initialization and more frequent ongoing rounds of selection, and resulted in a 16–19% higher overall response, than an alternative where each generation's males were crossed with the same generation's females. The strategy also yielded the highest short‐term benefit–cost ratio (13:1 versus 7:1 after 8 years of selective breeding) and the highest short‐ and long‐term value for participants in a breeding cooperative (a net present value of AU$28 million and an internal rate of return of 144% over 10 years), due to higher yields per fixed costs of production per unit area and due to savings in feed costs per kilogram of production. Breeding facilities of scale producing 50 full‐sibling families per generation were found to be more profitable than those producing 100 families.  相似文献   
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Handling and processing of potatoes is performed in increasingly large and more automated facilities, and the industry calls for more automated machinery for quality assessment and sorting by concentration of starch, soluble sugars, protein, amino acids etc. of the potato tubers. The present study was designed to evaluate five different scanning methods for their potential use in potato assessment and sorting. Two methods were based on hyperspectral imaging, two were based on dielectric/bio-impedance and one was based on low-field nuclear magnetic resonance. A set of 60 potatoes of 10 different cultivars were simultaneously sampled for analyses of content and scanned by the five different scanning methods. The resulting multivariate dataset was used to estimate the prediction ability of the individual scanning methods on starch-related parameters, selected simple sugars, selected amino acids, conductivity of pressed cell sap and cell sizes. Results showed that most types of spectral analyses had relatively high potential for predicting the starch-related parameters and medium potential for predicting the concentration of the reducing sugars fructose and glucose. Most methods showed medium potential for prediction of several amino acids, including asparagine, which showed particularly promising predictions in the hyperspectral analyses of intact potatoes. The presented screening study enabled us to perform robust choices for the further development and optimization of the methods and instruments for industrial implementation.  相似文献   
74.
Two demonstration sites in southeast Idaho were used to extend the scope of remote sensing of leafy spurge research toward investigating coarser scale detection limits. Hyperspectral images were obtained to produce baseline leafy spurge maps, from which spatially and/or spectrally degraded images were subsequently derived for comparative purposes with Landsat 5 Thematic Mapper (TM). The baseline presence/absence maps had an overall accuracy of 67% at the Spencer study site and 85% at the Medicine Lodge study site. Unexpectedly high-accuracy results were produced from the images that were spectrally degraded to the bandwidths of Landsat 5 TM, which suggests that high spectral resolution is not critical to leafy spurge detection. However, a classification using a Landsat 5 TM image indicates that the sensor is inadequate for regional distribution monitoring. The differences in results between the actual and degraded images suggest that a sensor with comparable resolutions but improved instrumentation (e.g., signal to noise) may offer an alternative to hyperspectral data for mapping leafy spurge at regional scales.  相似文献   
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The physiological effects of the hydrolysates of white rice protein (WRP), brown rice protein (BRP), and soy protein (SP) hydrolyzed by the food grade enzyme, alcalase2.4 L, were compared to the original protein source. Male Syrian Golden hamsters were fed high-fat diets containing either 20% casein (control) or 20% extracted proteins or their hydrolysates as the protein source for 3 weeks. The brown rice protein hydrolysate (BRPH) diet group reduced weight gain 76% compared with the control. Animals fed the BRPH supplemented diet also had lower final body weight, liver weight, very low density lipoprotein cholesterol (VLDL-C), and liver cholesterol, and higher fecal fat and bile acid excretion than the control. Expression levels of hepatic genes for lipid oxidation, PPARα, ACOX1, and CPT1, were highest for hamsters fed the BRPH supplemented diet. Expression of CYP7A1, the gene regulating bile acid synthesis, was higher in all test groups. Expression of CYP51, a gene coding for an enzyme involved in cholesterol synthesis, was highest in the BRPH diet group. The results suggest that BRPH includes unique peptides that reduce weight gain and hepatic cholesterol synthesis.  相似文献   
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Abstract: Papua New Guinea, with its heavy dependence on natural resources, limited economic development in the past two decades, poor record of governance and high‐profile separatist conflicts such as the Bougainville civil war, appears to be an exemplar of the ‘Resource Curse’ theory – the notion that natural resources actively undermine economic development. Using a number of examples from a range of scales, this paper argues that what appear to be ‘resource’ conflicts in Papua New Guinea are actually better conceived as conflicts around identity and social relationships. The very different conceptualisation of natural resources in most Melanesian societies – as elements of the social world as much as any external environmental sphere – means that resources become a conduit for local social and political agendas and tensions to be expressed. The nature of traditional conflict in Melanesian societies is discussed as a guide to the better management and resolution of what appear to be ‘resource’ conflicts in Papua New Guinea.  相似文献   
79.
The challenges facing potato breeding have actually changed very little over the years with resistance to pests and pathogens remaining high on the agenda together with improvements in storability, reduction in blemishes, and novelty and consistency in cooking/processing qualities. The need to expand the range of targets for potato improvement is being driven by requirements for reduced agrochemical usage and by predictions of the effects of changing climates. Thus fertiliser and water use efficiency are moving up the political agenda. Genetic variation present in germplasm collections needs to be harnessed to provide the genes and alleles required. This paper provides examples of the functional genomics tools and approaches being developed and deployed to provide new options for advancing the breeding of next generation crops. Whilst genetic modification (GM) approaches remain contentious in Europe, this paper will also provide some recent examples of the range of potential impacts that GM approaches could make. It will also consider the value of so-called intragenic or cisgenic approaches to potato genetic engineering.  相似文献   
80.
BACKGROUND: Management of early leaf spot (Cercospora arachidicola Hori.), late leaf spot [Cercosporidium personatum (Berk. & MA Curtis) Deighton] and stem rot (Sclerotium rolfsii Sacc.) of peanut (Arachis hypogaea L.) in the southeastern USA is heavily dependent upon sterol biosynthesis inhibitor (SBI) and quinone outside inhibitor (QoI) fungicides. Effective new fungicides with different modes of action could improve overall disease control and extend the utility of the current fungicides. Penthiopryad is a pyrazole carboxamide fungicide being evaluated for use on peanut. Field experiments were conducted from 2004 to 2007 to determine the effect of a range of rates (0–0.36 kg AI ha?1) of penthiopyrad on leaf spot and stem rot and the relative efficacy of penthiopyrad and current fungicide standards chlorothalonil, tebuconazole and azoxystrobin. RESULTS: Leaf spot control in plots treated with penthiopyrad at 0.20 kg AI ha?1 or higher was similar to or better than that for the chlorothalonil standard. The incidence of stem rot for all penthiopyrad treatments was usually less than that for the tebuconazole or azoxystrobin standard treatments. Pod yields for all penthiopyrad treatments were similar to or higher than those for the respective standards. CONCLUSION: Penthiopyrad has excellent potential for management of late leaf spot and stem rot of peanut, and may complement current SBI and QoI fungicides. Copyright © 2008 Society of Chemical Industry  相似文献   
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