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1.
伊犁是全国最大的薰衣草种植基地,薰衣草作为该区的特色作物给当地经济带来很大效益,为团场增效、职工增收、边疆社会稳定做出贡献。薰衣草除了提炼薰衣草精油和制作干花产品外,在园林观赏、食品、饮料、医疗保健、美容等领域也具有广阔的市场,以薰衣草产业为龙头,可带动其它相  相似文献   
2.
为研究生物刺激剂对玉米的增产提质效果,试验探讨不同生物刺激剂对玉米的产量和品质方面的影响,为鲜食玉米的优质高产栽培提供技术支撑。以鲜食玉米‘钱江糯3号’为试验品种,以3种生物刺激剂(阿美滋、美基、保康灵1号)为供试药剂,设置6个处理(阿美滋1000倍液、阿美滋1500倍液、阿美滋2000倍液、美基3000倍液、保康灵1号300倍液、清水对照),研究大田常规施肥水平下药剂对‘钱江糯3号’的经济性状、产量及品质的影响。在阿美滋1500倍液喷施下,玉米的行粒数、单穗鲜重和单穗净重、产量均最高,蛋白质含量、粗纤维含量、还原糖含量、淀粉含量均居第3位;在保康灵1号300倍液喷施下,玉米的穗粗最高,单穗鲜重、单穗净重、产量均居第2位,蛋白质含量最高,脂肪含量最低,还原糖含量居第2位。阿美滋1500倍液在增加玉米产量上是最佳选择,保康灵1号300倍液则对提升玉米品质最有效果。建议生产上将阿美滋1500倍液与保康灵1号300倍液配合施用,这对鲜食玉米的增产提质效果最好。  相似文献   
3.
Essential oils are plant-derived aromatic volatile oils, and they contain bioactive compounds that have been shown to improve poultry nutrition. In this study, we investigated the effects of oregano essential oil (OEO) on intestinal antioxidative capacity, immunity, and gut microbiota of young yellow-feathered chickens. A total of nine hundred and sixty 1-d-old female Qingyuan partridge chickens were randomly allocated to four treatment groups with six replicates of 40 birds each, and the feeding trial was lasted for 30 d. The controls were fed on a basal diet without in-feed antibiotics; the birds in the antibiotic group were fed the basal diet supplemented with 20 mg/kg virginiamycin; the remaining birds were fed the basal diet containing 150 or 300 mg/kg OEO, respectively. Dietary supplementation with 150 or 300 mg/kg OEO increased average daily feed intake (P = 0.057) and average daily gain (P < 0.05). The activities of glutathione peroxidase and total antioxidative capacity in plasma, jejuna, and ileal mucosa were increased by OEO supplementation (P < 0.05), with a trend of lower jejunal content of malonaldehyde (P = 0.062). Moreover, dietary OEO increased the content of secretory immunoglobulin A (P = 0.078) and the relative expression of Claudin 1, Mucin 2, and Avain beta-defensin 1 in ileum (P < 0.05). Sequencing data of 16S rRNA indicated that dietary OEO increased the relative abundance of Firmicutes phylum, and Clostridium and Lactobacillus genera, and decreasing that of Romboutsia. Functional analyses indicated that microbial amino sugar and nucleotide sugar metabolism, replication, and repair systems were higher in OEO groups than those of controls and antibiotic treatment. In conclusion, dietary supplementation with OEO enhanced growth performance, alleviated local oxidative stress in intestine, improved production of natural antibodies, and favorably modulated intestinal microbiota composition.  相似文献   
4.
The practice of catch-and-release fishing has been widely promoted by angling fraternities as a fisheries manage- ment tool. The aim of this investigation was to determine the physiological response of Orange-Vaal smallmouth yellowfish, Labeobarbus aeneus, to catch-and-release angling in the Vaal River, South Africa. Fish were collected using standard fly-fishing techniques, anaesthetised in clove oil and blood was drawn from the caudal vein; thereafter the fish were weighed, measured, revived and released. Blood plasma was analysed for concentra- tions of glucose, cortisol and lactate to determine the effects of angling duration, fish size and water tempera- ture. Larger fish were angled for a longer duration compared with smaller fish. Levels of glucose were affected by water temperature (influenced by time of year). Plasma glucose concentrations decreased with greater angling duration. Few individuals (n = 12) showed increased plasma cortisol concentrations. In extended-capture fish (angled for >1 min), lactate concentrations increased significantly above values for rapid-capture fish (angled for >30 s). These data suggest that catch-and-release causes physiological stress to fish, but nonetheless this practice can be a valuable fisheries management tool to ensure the sustainability of fish populations. Other factors beyond the ‘angling’ time are likely to contribute to physiological disruptions in homeostasis and therefore handling and air exposure of angled fish should be included in future catch-and–release angling studies. In addition, the longer-term impact of angling on fish health should also be determined.  相似文献   
5.
Mammalian parental investment (i.e. care of descendant offspring) is largely biased towards maternal contributions due to the specific feeding needs of mammalian offspring; however, varying degrees of paternal investment have been reported in about 10% of all mammalian species. Within the order Carnivora, paternal contribution to rearing offspring is particularly high: an estimated 32% of all studied carnivore species exhibit direct paternal care. Despite the prominence of paternal investment in carnivores, the endocrine basis of this behaviour is not well understood. This review examines the current – highly constrained – state of knowledge about the endocrine basis of carnivore paternal investment. We attempt to link changes in androgen and glucocorticoid levels with variation in direct and indirect paternal care behaviour making specific predictions regarding the way forward. Well-studied species, such as bat-eared foxes (Otocyon megalotis), dwarf mongoose (Helogale parvula) and meerkats (Suricata suricatta), where social dynamics are relatively well understood, can act as ideal model systems through which we may further investigate the endocrine basis of paternal investment in carnivores.  相似文献   
6.
红酵母的性质及其应用研究   总被引:10,自引:0,他引:10  
红酵母是酵母菌的一个属,腐生,分布广泛,在医学、食品、化工和农业等方面都有一定的应用,但目前并没有引起人们足够的重视。综述了红酵母的种属特性、理化特性、培养及其应用。  相似文献   
7.
浚县种子公司是全国种业五十强企业之一.多年来,公司坚持诚信为本、质量第一的理念,在科技创新、生产经营、质量管理等方面大力实施丰黎品牌战略,2004年丰黎牌小麦种子被河南省名牌战略推进委员会评选为河南省名牌农产品.  相似文献   
8.
Some properties of feasible direction in the convx case are generalized to, the corresponding properties in generalized covex case and their applications for multiobjective mathematical programming are discussed in this paper.  相似文献   
9.
茶树钾营养特性的研究   总被引:5,自引:0,他引:5  
王晓萍  阮建云 《作物学报》1995,21(3):324-329
本文对我国主要茶区茶园土壤的含钾状况,茶树品种和土壤水分对茶树吸收钾的影响和茶园施肥钾肥的增产效果进行了系统研究。结果表明,我国有近60%的茶园土壤处于罐钾状态,这已成为限制茶叶高产优质的主要障碍因子之一。不同品种茶树对钾的吸收具有明显差异,它们对钻的最大速率Vmax为龙井43>碧云>苹云>碧峰>菊花春,米氏亲和常数Km为碧峰>碧云>龙井43>苹云>菊花春。干旱处理的茶树体内累积的钾和叶片的含钾量  相似文献   
10.
介绍了γ透射法应用于大型高精度称重式土壤蒸渗仪上的研究情况,并说明了如何利用计算机对其土壤剖面上30个测点的数据采集系统实行自动实时测定处理及控制。它为田间蒸散和降水入渗试验研究提供了一种先进的测量方法和技术手段。  相似文献   
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