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A line-source sprinkler irrigation system was used for irrigation-fertilizer cowpea (Vigna unguiculata [L.] Walp.) production studies. The relative merits and demerits of irrigating frequently but with smaller amounts of water than the design water application depth as compared to stage-of-growth and normal interval irrigation were investigated with five levels of fertilizer P, three water levels and five irrigation schedules.Dry matter production on the basis of forage produced was used as the yield indicator. The plants were harvested when the more advanced individuals reached the late boot stage immediately preceding the appearance of their inflorescences. P uptake was also measured.Statistical analyses of yield and P uptake gave a positive response of the crop to added fertilizer and irrigation water. Application of 70 kg/ha P2O5 produced the highest yields under all irrigation schedules. Irrigating too frequently was found to be detrimental; maximum yield under P fertilization was obtained with irrigations scheduled at half the design interval and with half the design irrigation depth. Uptake of P increased with yield.  相似文献   
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Summary Striking similarities appear to exist between selected protoplast-derived variants (PD-clones) of the potato cultivar Russet Burbank, and commonly occurring somatic potato sports, called bolters. A limited survey of individuals involved in the certification of Russet Burbank, revealed that bolters do commonly occur in this variety, are highly variable, and sometimes occur at high frequency. It is therefore suggested that bolters and the more promising selected PD-clones of Russest Burbank may be one and the same, arising from the same type of macromutation.One selected PD-clone, three different Russet Burbank bolters, and two controls were analyzed for 15 isozymes in the hope of determining if bolters and promising PD-clones belong to the same class of variants. No isozyme variation between Russet Burbank and its subclones was observed. The breeding value of protoplast-derived variation is discussed in this light.Approved by the Director of the New York State Agricultural Experiment Station for publication as Journal paper No. 3554, Oct. 19, 1983.  相似文献   
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The main function of the single whey acidic protein domain (SWD)-containing protein in shrimp is unknown. To elucidate the function of the SWD-containing protein in vivo, the SWD-containing protein gene was isolated and characterized. A 9.3-kb shrimp SWD-containing protein gene, and a 3.9-kb 3′-flanking region. The shrimp SWD-containing protein gene contained three exons and two introns. Different fragments of the shrimp SWD-containing protein 5′-flanking region were transfected into HeLa cells. The promoter activities were assayed by basal human chorionic gonadotropin (HCG), luteinizing hormone-releasing hormone (LRH), and gonadotropin-releasing hormone (GnRH) treatments. The in vitro actions of the SWD-containing protein promoter expression pattern were studied by transfection of an SWD-containing protein promoter (1 kb)-driven green fluorescent protein (GFP) encoding the GFP cDNA transgene into the HeLa cell line, which was then microinjected into zebrafish Danio rerio embryos. These results indicate that the shrimp SWD-containing protein promoter might play an important role in gene regulation of sex hormones in mammalian cell lines and in gene regulation of developmental stages in zebrafish.  相似文献   
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Groupers are popular aquaculture species in South-East Asia, but their cultivation is affected by infectious disease outbreaks. Mucosa-associated lymphoid tissues provide a first-line defence against pathogens; however, few studies are available relating to cellular or proteomic responses of mucosal immunity in grouper. Skin, gill and intestine were sampled from brown-marbled grouper Epinephelus fuscoguttatus (Forsskål, 1775) at 4 and 96 hr post-infection (hpi) and 7 days post-infection (dpi) following intraperitoneal infection with Vibrio harveyi, and stained with haematoxylin/eosin and Alcian Blue/periodic acid–Schiff. Skin mucus was analysed by 2D-gel electrophoresis, and proteins modulated by the bacterial infection identified. In the infected fish, significant increases in sacciform cells in skin and increased levels of nucleoside diphosphate kinase in mucus were detected at 4 hpi. At 96 hpi, goblet cells containing acidic mucins significantly increased in the intestine, while those containing mixed mucins increased in skin and gills of infected fish. Proteasome subunit alpha type-I and extracellular Cu/Zn superoxide dismutase levels also increased in mucus. Rodlet and mast cells did not appear to respond to the infection. Mucosal tissues of grouper appeared actively involved in response to Vibrio infection. This information may help future research on improving grouper health, production and vaccine development.  相似文献   
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A commercial micropulverized 50% crude protein diet for penaeid culture was studied for biochemical oxygen demand and to assess its effect upon water quality in the hatchery and raceway environment. The feed was separated into 13 sizes ranging from 250 μm to 2 mm in diameter. The first order reaction rate constant (k) increased with decreasing particle size. The micropulverized feed was highly biologically reactive and the rate constant (k) varied from 0.1 to 0.24 day-1, depending on the particle size. The ultimate BOD was 660 mg/g. The goal of this research was to predict the impact of this feed in relation to varying particle size upon the oxygen and ammonia dynamics of the water. This information will enable shrimp hatchery managers to more effectively assess the water quality impact and water replacement schemes when using artificial micropulverized feeds.  相似文献   
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Pleurotus citrinopileatus is a popular edible mushroom which is physiologically active in both humans and animals. In the study we investigate the effects of this mushroom on hyperlipidemic hamster rats. Four dietary forms of the mushroom were created as follows. The powdered dry fruiting body, hot-water extract, and two kinds of elutes were obtained, from ethyl acetate extract and methanol extract, respectively, in different mixed proportion solvents over silica gel column chromatography (referred to as EAE and MOE, respectively). They were tested at different dosages as a supplement to a high-fat diet in hyperlipidemic rats. Serum triglycerides and total cholesterol levels were significantly lower in groups supplemented with the highest dosages of EAE and MOE (0.5 g/kg, body weight daily) as compared with the control groups that received no mushroom additive. High-density lipoprotein levels in these same two experimental groups were also significantly higher than those in the negative control group. The tested rats that were fed with EAE had the highest serum glutathione peroxidase and superoxide dismutase activity, and those with the MOE and EAE had the highest DPPH free radical scavenging activities and ferric-reducing abilities, tested in vitro. The major constituents of MOE and EAE were identified as ergosterol and nicotinic acid, respectively. P. citrinopileatus extracts may have a significant antihyperlipidemia effect. Furthermore, antioxidant activities and antihyperlipidemic effects of MOE and EAE seemed to display similar tendencies.  相似文献   
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