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131.
A total of 147 samples of garlic ( Allium sativum ) bulbs affected by blue mould were obtained from a variety of agroclimatic districts between December 1999 and February 2000. Penicillium species were identified using both morphological and chemotaxonomic characteristics. Penicillium allii was the predominant species isolated (81·8%) in this survey and the only species proven to be pathogenic on garlic. Other species were isolated much less frequently: P. chrysogenum (13·7%), P. brevicompactum (2·8%), P. phoeniceum (0·9%), P. aurantiogriseum (0·6%) and P. flavigenum (0·2%). Colonies of P. allii could be classified into four morphotypes and their distribution seemed to be influenced by seed trade and agricultural practices. Penicillium allii isolates were grouped into three aggressiveness phenotypes (low, medium and high) based on their ability to cause disease during field trials on susceptible (Fuego INTA) and less susceptible (Castaño INTA) garlic cultivars. The number of surviving plants at 191 days after planting and postharvest bulb weight contributed the most towards aggressiveness modelling.  相似文献   
132.
暨诚欣  刘志平 《经济动物学报》2005,9(4):194-197,214
为探讨行之有效的精液保存方法,提高狐人工授精技术的效率,对9只种公蓝狐的精液进行了常温保存与低温保存试验。结果表明,常温保存精液精子平均存活时间为26.2 h,平均生存指数为12.75;低温保存精液精子平均存活时间为40 h,平均生存指数为17.92。低温保存可以延长精子的体外存活时间。数据分析结果表明,低温保存生存指数与常温保存生存指数的比值与常温保存生存指数呈线性关系,即低温保存效果与精液品质呈正相关,精液品质越高,低温保存效果越好。  相似文献   
133.
Fe(Ⅲ)-H_2O_2-甲基蓝体系催化动力学光度法测定痕量Fe(Ⅲ)   总被引:4,自引:0,他引:4  
在 H2 SO4 介质中 ,痕量 Fe( )对 H2 O2 氧化甲基蓝褪色反应具有较强的催化作用 ,据此建立了一种催化动力学光度法测定痕量 Fe( )的新方法 .该方法的线性范围为 0 .0 192 - 0 .0 6 6 0μg· m L-1,检测限为 8.0 1×10 -10 g· m L-1.用于水样中痕量 Fe( )的测定 ,结果满意 .  相似文献   
134.
测定植物样品全氮含量的两种方法比较   总被引:5,自引:0,他引:5  
比较了植物全 N测定的两种方法即开氏——蒸馏法和靛酚兰比色法 ,讨论了二者的各自特点 ,并对二者的测定结果进行方差分析 ,结果表明 ,二者差异不显著 ,比色法测定结果与蒸馏法一致 ,另外认为靛酚兰比色法适合于大批植物全 N含量分析 ,比蒸馏法更快捷  相似文献   
135.
斑节对虾幼体链壶菌病的防治试验   总被引:1,自引:0,他引:1       下载免费PDF全文
在斑节对虾无节幼体池前2~3小时用0.015~0.020mg/L浓度的亚甲基蓝或三氟乐灵作预防,1~2天后发现有链壶菌感染时再用0.020mg/L浓度的亚甲基蓝或0.020~0.030mg/浓度的三氟乐灵治疗。两种药物比较,三氟乐录能有效防治链壶菌病,其有效浓度为0.020~0.050mg/L;而亚甲基蓝在链壶菌感染不严重时才有效,若感染严重或无节幼体下池前未施药预防,待发病后再用药,治疗无效。  相似文献   
136.
As the quest for marine-derived compounds with pharmacological and biotechnological potential upsurges, the importance of following regulations and applying Responsible Research and Innovation (RRI) also increases. This article aims at: (1) presenting an overview of regulations and policies at the international and EU level, while demonstrating a variability in their implementation; (2) highlighting the importance of RRI in biodiscovery; and (3) identifying gaps and providing recommendations on how to improve the market acceptability and compliance of novel Blue Biotechnology compounds. This article is the result of the work of the Working Group 4 “Legal aspects, IPR and Ethics” of the COST Action CA18238 Ocean4Biotech, a network of more than 130 Marine Biotechnology scientists and practitioners from 37 countries. Three qualitative surveys (“Understanding of the Responsible Research and Innovation concept”, “Application of the Nagoya Protocol in Your Research”, and “Brief Survey about the experiences regarding the Nagoya Protocol”) indicate awareness and application gaps of RRI, the Nagoya Protocol, and the current status of EU policies relating to Blue Biotechnology. The article categorises the identified gaps into five main categories (awareness, understanding, education, implementation, and enforcement of the Nagoya Protocol) and provides recommendations for mitigating them at the European, national, and organisational level.  相似文献   
137.
Expression of HSP70 in response to heat-shock was investigated at the protein and mRNA levels in Mediterranean blue mussel. Western and Northern blot analyses revealed that HSP70 was expressed following heat-shock in the mantle at both protein and mRNA levels, suggesting that gene expression of HSP70 is implicated in the cellular response to heat-shock stress in mussel. It was then attempted to clone HSP70 cDNA in order to determine the primary structure of mussel HSP70. As a result, two full-length cDNA encoding HSP70 were isolated from a cDNA library prepared from the heat-shocked mantle. The isolated cDNA consist of single open reading frames of 2067 bp and 1911 bp which encode proteins of 689 amino acids and 637 amino acids, respectively. Both HSP70 cDNA encode an ATPase do main, and a substrate-binding do main in addition to a Glu-Glu-Val-Asp (EEVD) peptide motif that is specific for cytosolic HSP70. These findings suggest that the cDNA clones obtained in the present study encode cytosolic HSP70.  相似文献   
138.
采用甲苯胺蓝染色和Golgi镀银法对柄海鞘神经复合体的结构进行显微观察,并通过免疫组织化学方法对甲硫氨酸脑啡肽在神经复合体中的分布进行了研究。①甲苯胺蓝染色法显示,神经复合体由神经节、神经腺和疏松结缔组织组成;神经节分为皮质部、髓质部和过渡带;神经腺位于神经节背侧面,由腺小叶组成;神经细胞呈深蓝色,神经纤维呈浅蓝色,与背景反差较大。Golgi镀银法显示的结果不理想,神经细胞和神经纤维着色不明显。②免疫组化结果显示,M-ENK在神经复合体中分布广泛,神经细胞、神经纤维及上皮细胞均有Met-ENK阳性反应。  相似文献   
139.
Abstract –  Ecology of larval blue sucker, Cycleptus elongatus , a North American catostomid that has declined throughout its range, is poorly known because larvae have rarely been sampled. A total of 316 young blue suckers (16.0–39.0 mm total length) was captured over 3 years at 14 off-channel sites in Pool 25, Mississippi River. Blue suckers demonstrated distinct temporal and spatial abundance patterns. Blue suckers were only captured in late May/early June, and were more abundant during a year of little flooding. Abundance was correlated with the distance a site was from the main channel, being highest in island borders and island sloughs in proximity to the channel. Fish guts contained a relatively high biomass of chironomids and zooplankton, suggesting islands were providing suitable feeding opportunities. Because of their proximity to flows, slack waters provided by islands were accessible to blue sucker larvae dispersing from channel spawning areas and facilitated their development into rheophilic juveniles.  相似文献   
140.
为探究柚子皮对染料废水的吸附规律及最佳条件,以亚甲基蓝模拟废水,进行了柚皮粉对亚甲基蓝的吸附规律及吸附效果试验。结果表明:在温度30℃,pH 8,震荡时间60min的条件下,0.4g柚皮粉可使100mL浓度为140mg/L亚甲基蓝的去除率达83%以上,30℃下柚子皮理论饱和吸附量为133mg/g。柚子皮吸附亚甲基蓝的过程以物理吸附为主,包括外部液膜扩散、表面吸附和颗粒内部扩散等过程,可以用Langmuir、Temkin等温吸附方程和二级吸附速率方程进行很好的描述。  相似文献   
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