952 resultados para Aspergillus japonicus


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Between June 1995 and May 1996 seven rookeries in the Gulf of California were visited four times in order to collect scat samples for studying spatial and seasonal variability California sea lion prey. The rookeries studied were San Pedro Mártir, San Esteban, El Rasito, Los Machos, Los Cantiles, Isla Granito, and Isla Lobos. The 1273 scat samples collected yielded 4995 otoliths (95.3%) and 247 (4.7%) cephalopod beaks. Fish were found in 97.4% of scat samples collected, cephalopods in 11.2%, and crustaceans in 12.7%. We identified 92 prey taxa to the species level, 11 to genus level, and 10 to family level, of which the most important were Pacific cutlassfish (Trichiurus lepturus), Pacific sardine (Sardinops caeruleus), plainfin midshipman (Porichthys spp.), myctophid no. 1, northern anchovy (Engraulis mordax), Pacific mackerel (Scomber japonicus), anchoveta (Cetengraulis mysticetus), and jack mackerel (Trachurus symmetricus). Significant differences were found among rookeries in the occurrence of all main prey (P≤0.04), except for myctophid no. 1 (P>0.05). Temporally, significant differences were found in the occurrence of Pacific cutlassfish, Pacific sardine, plainfin midshipman, northern anchovy, and Pacific mackerel (P<0.05), but not in jack mackerel (χ 2=2.94, df=3, P=0.40), myctophid no. 1 (χ 2=1.67, df= 3, P=0.64), or lanternfishes (χ 2=2.08, df=3, P=0.56). Differences were observed in the diet and in trophic diversity among seasons and rookeries. More evident was the variation in diet in relation to availability of Pacific sardine.

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本文研究了富贵草对模拟光斑的光合响应、银杉对光的适应性以及大叶黄杨叶片内部光能利用梯度三个方面的问题。 1)研制了用于林内光环境调查和研究的光量子计组件。 关键词:光量子计,A/D板 2)以亚热带常绿阔叶林下一种常见的灌木富贵草为研究对象,利用气体交换和叶绿素荧光技术研究了其对模拟光斑的光合响应。在同样辐射通量(非光抑制)的情况下,光合诱导过程中光斑可以提高富贵草对光斑的利用能力(光斑诱导的碳同化量可高出对照48%)。叶绿素荧光测量结果表明:1)光斑与光斑之间的暗期发生了qN弛豫过程;2)暗期之后的光期光化学能量转换效率提高。强光光斑簇可以诱导富贵草光抑制的产生,但程度较连续光低。 关键词:模拟光斑, 叶绿素荧光, 光诱导过程 3)用高效液相色谱(HPLC)和77K低温荧光发射光谱技术来研究快速诱导组分发生的时间内光斑所导致NPQ (qN)降低的生理原因。在非光抑制条件下,光斑造成的NPQ (qN)降低的生理原因包括叶黄素循环的变化及LHCIIs聚集态的变化;此外低温荧光数据还显示光斑导致的PSII/PSI荧光产量比率要高于连续光,说明光斑导致植物对于光的利用增加。以上结果说明模拟光斑诱导了富贵草内囊体膜较低水平的能态。 关键词:模拟光斑,叶黄素,聚集态 4)用气体交换等技术测定了部分银杉幼树的生理生态指标,用鱼眼镜头测定了所测叶片的林冠开度(OP)。研究了沿林冠开度梯度的银杉幼树对光的适应性。银杉幼树在林窗边缘表现出较好的适应性,包括高的ISG(综合地上部分茎生长),高的HG(当年生树高生长速率),较高的LMA(单位叶片面积干物质重),较高的Pns(单位叶片干物质水平的净光合速率),高的单位叶片的碳同化速率,较高的截获光的单位叶片的叶面积等等,可以初步确定银杉属于Gap树种:在所测定的范围内(0. 00139%-0. 0109%)TN(土壤总氮量)明显不如OP对银杉幼树生长的影响大;综合的生态可塑性指标必须考虑具体的实验地情况、选取合适的形态学和生理学的因子、并结合多个相似生长环境下的树种来进行考虑。 关键词:林冠开度,生理生态指标,生态可塑性 5)分析了湖南八面山的银杉的某些光合特性,并比较了极郁闭( OP<4%)情况下银杉当年生叶片与大树顶端枝条(OP>30%)当年生叶片之间光合特性上的差异。极郁闭情况下银杉叶片生长出现黄化现象,但银杉幼苗又不耐强光。银杉幼苗一天的光合动态变化表明,银杉最大光合速率在早晨8:00左右,当光照超过光饱和点时,净光合速率迅速下降,其后略有回升,呈不太典型的双峰模式。气孔关闭与净光合速率的下降有密切的关系。早晨8:00到11:00间叶黄素循环运转,对光合系统起到一定保护作用。 关键词: 银杉,色素分析,光合作用 6)采用一种新方法来测量大叶黄杨叶片内部的绝对光能利用效率梯度的曲线。该方法基于光声光谱的深度分析(Depth-Analysis)理论,并结合了光纤微探测器的叶片光梯度测量结果。日本小檗(Berberis thunbergii DC.)叶片的光声光谱扫描显示了深度分析的精确性。实验结果表明:叶片内部利用光能效率最低处在栅栏组织和海棉组织之间(入射光能的0.026%-660nm红光);越靠近叶片的上表皮和下表皮,趋势显示叶片组织利用光能效率有上升的趋势(分别为0.092%,0.036%)。因此,不同叶肉组织绝对光能利用效率是不同的,该实验结果直接证实了Han &Vogelmann 1999b所提出的假设。 关键词: PA深度分析 叶片内部的光梯度 光化学损失 光吸收梯度

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紫茎泽兰(Eupatorium adenophorum Spreng.)作为重要的外来入侵种之一,已严重破坏了入侵地生态系统的结构与功能,同时使当地农林业生产蒙受巨大的损失。因此,明确紫茎泽兰的竞争策略与扩散潜力,对制定合理的控制措施具有重要意义。 土壤氮素增加常常有助于外来种的入侵,那么降氮能否抵制入侵呢?向土壤中添加碳素,增强微生物对氮素的吸收,从而降低土壤中可被植物吸收的氮素是目前常用的降氮方法。为检验这一假说对入侵种紫茎泽兰的适用性,选取入侵种紫茎泽兰和本地种禾本科雀麦(Bromus japonicus)、菊科鱼眼草(Dichrocephala integrifolia),分别单栽或与紫茎泽兰混栽,向各植物组合中添加碳素(按1650克有机质/平方米计)或氮素(按30克氮素/平方米计),并设立对照进行盆栽实验。在碳素添加条件下,紫茎泽兰地上与地下生物量分别比对照降低了71.9% 和 74.9%,而本地种的生物量却没有受到显著影响。同时,碳素添加导致紫茎泽兰对本地种的竞争强度(RII)明显下降。氮素添加则减弱或逆转了上述碳素的作用。因此,向土壤中添加碳素有助于抵抗氮沉降对外来种入侵的促进作用,特别对抵御那些与氮素有亲和力的入侵种更为有效。在不同氮素条件下,紫茎泽兰对本地种竞争中,资源竞争强度均明显大于化感作用。尽管在紫茎泽兰发育早期化感作用较小,但是,碳素添加使紫茎泽兰可利用氮素减少,激发了化感作用在竞争中占有更大的比例,说明资源竞争与化感是相互结合、共同发挥作用的。 去叶作为模拟采食方法之一,至少可以通过两种方式影响植物竞争。一是去叶对目标种生长产生负面影响,二是邻种去叶有利于目标种生长,进而改变种间竞争关系。基于以上假定,对紫茎泽兰与相邻本地种分别单栽、同种合栽和异种混栽,进行去叶处理。结果恰与假定相悖:在整个生长季内,去叶增加目标株生物量的1.0 – 198.9%。对于入侵种而言,当邻居本地种去叶时,紫茎泽兰能完全弥补竞争产生的负面效应,即它与未去叶的单栽紫茎泽兰生长无显著差异;而紫茎泽兰去叶降低了相邻本地种的生长,加剧了原本由于竞争给对本地种带来的负面影响。因此,去叶效应与邻种的存在与否及邻种的类型均有关。在应用生物控制对目标株采食时,特别是在没有造成严重伤害或致死情况下,可以使本来具有竞争优势的入侵种变得更具强势。竞争与去叶之间存在复杂的相互作用,采食带来的间接效应可能比预想的更为复杂。因此,在生物控制措施实施之前,充分地估计生物控制的间接作用至关重要。 为检验反应—扩散模型(reaction–diffusion model)能否正确模拟紫茎泽兰小尺度扩散速率,本研究调查了四川攀枝花山区5个不同的生境的紫茎泽兰群落。对各样地内紫茎泽兰定位和年龄确定,基于克里金插值法做出其入侵格局的等年线图,通过等年线之间的垂直距离即可得到紫茎泽兰扩散速率的经验值。同时,计算内禀增长率和扩散系数,根据模型计算得到扩散速率的预测值。结果表明:紫茎泽兰扩散速率经验值明显小于模型预测值。因此,尽管反应—扩散模型已在大尺度扩散预测方面得到广泛的应用和验证,但在小尺度上,由于没有借助于复杂的生活史模型和分层模型,单凭反应—扩散模型不足以得到准确的预测。另外,在没有遭受干扰的生境中,可以发现紫茎泽兰扩散早期存在明显的时滞期。倘若这种时滞效应在入侵扩散中是频繁发生的,那么在判定物种是否具有入侵性时,很可能由于物种处于时滞期而被误认为非入侵种。 基于紫茎泽兰入侵至中国60年来所收集到的441已知分布记录和23个环境变量,采用GARP模型对其潜在分布范围做出了预测,并通过Kappa和ROC(receiver–operator characteristic)对预测结果进行检验。结果表明紫茎泽兰目前分布以云贵高原为主体,逐渐向四川盆地东部、山东半岛、东南沿海、台湾沿海以及海南岛等地扩散。冷季降水量、年极端低温和年均最高温对分布影响较大。RDA(Redundancy Analysis)分析结果显示温度和降水是限制紫茎泽兰扩散的重要因素。在过去的20年里,紫茎泽兰已经从温度较高、天气波动较小的亚热带气候逐渐向气候温凉、降水减少的高海拔地区扩散。紫茎泽兰可以适应相对较宽的温度和降水梯度,年均温度在10—22 ˚C,年降水量在800—2000 mm区间均有分布。本研究结果为发展早期预警工作、防止紫茎泽兰在中国进一步入侵提供了科学依据。

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The effects of temperature and relative humidity on the rate of drying of split open fish and salted fish in a tunnel dryer have been studied at a constant air velocity. By a judicious combination of these two, the rate of drying could be considerably accelerated, 10 to 12 hours only being required for drying to moisture levels below 30% in the case of mackerel, lactarius, otolithes and kilimeen (Nemipterus japonicus)

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Adults of Penaeus japonicus (Bate) and juveniles of P. canaliculatus (Olivier) were recorded for the first time from the coastal and estuarine regions of Goa respectively. Their presence in Goa waters suggests that both the species have a wide distribution along the west coast of India. The available data from the neighboring states suggest that both the species are distributed in deeper waters and are caught during or immediately after the southwest monsoon. Hence, it may be possible to tap these valuable resources from Goa waters if the fishing operation is extended to depths beyond those presently fished and fishing is carried out during the SW monsoon season.

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This investigation was carried out from June ‘89 to May ‘90 and focuses on the occurrence and abundance of Acetes shrimps in the Kutubdia channel. The shrimps of the genus Acetes occurred throughout the year in the area of investigation. Acetes showed a bimodal peak in occurrence, one in late monsoon season (August - September) and other in pre-monsoon season (February - March). But the maximum number of Acetes shrimps was recorded in March (462 individuals/haul). The Acetes population of this channel was dominated by four species, Acetes erythraeus (38.50%), A. indicus (32.98%), A. chinensis (4.48%) and A. japonicus (3.32%).

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The present communication is a survey report carried out to assess the incidence of toxic mycoflora on seven types of agriculture products/by products incorporated during fish culture as supplementary dietary items. Samples were obtained from various sources at Darbhanga, Madhubani and Samashtipur districts during summer, winter and monsoon months. Out of the total 1774 samples, only 894 appeared to be fresh visually reflecting average incidence of contamination around 46.6%. However, the apparently fresh samples, when subjected to culture, 26.9% of them were found to be contaminated. Thus, degree of fungal spoilage in feed ingredients in parts of north Bihar appears to be significantly high (73.5%). The present study illustrates the facts with special reference to Aspergillus flavus, A. parasiticus (elaborating aflatoxins) A. ochraceous, Penicilium viradicatuin (elaborating ochratoxins) and A. versicolor (elaborating sterigmatocystin). The other strains already known for their toxigenic potentials that appeared on the present substrates included A. niger, A. fumigatus, A. candidus, P. islandicum, Rhizopus spp. and Mucur spp. Studies indicate that the prevalent climatic factors like temperature and relative humidity facilitate a congenial condition almost all through the year and in particular during summer and monsoon months. But water content of the substrates is a vital factor that further accelerates the pace of mycobial spoilage. A thorough sun-drying of the agricultural commodities before prolonged storage to bring water content below the "low risk limit" may significantly reduce the incidence of molds.

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The geographic and bathymetric distribution of the shrimps Penaeus indicus, Metapenaeus monoceros, P. japonicus and P. monodon along the coast of Mozambique are given. Biological data of the main species P. indicus and M. monoceros are presented.

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From November 18th to December 17th 1982, the SRTM "Sebastopolsky Rybak" carried out research cruises on the Sofala Bank in the area between 16°20'S and parallel 19°40'S. The authors analyze data collected on biological characteristics, sexual maturity and localization of Penaeus indicus, Metapenaeus monoceros, Penaeus japonicus, Penaeus monodon and Penaeus latisulcatus.

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本发明涉及杀虫剂领域,具体地说是一种海藻内生真菌二萜生物碱类化合物及其制备和应用。具体结构式如(I)所示,其制备方法为将米曲霉(Aspergillus oryzae)cf-2接种于培养基中静止发酵,发酵液经乙酸乙酯萃取浓缩,菌丝体用有机溶剂提取,再经乙酸乙酯萃取浓缩,合并浓缩物,得到粗提物;粗提物进行硅胶柱层析,用有机溶剂进行梯度洗脱,收集洗脱液,洗脱液经薄层层析检测;将以洗脱液体积比5-8:1梯度的洗脱组分进行凝胶柱层析、硅胶柱层析和薄层层析分离纯化得目标化合物。本发明获得的海藻内生真菌二萜生物碱类化合物,经杀虫活性实验得出化合物在100微克/毫升时对卤虫的致死率为42.9%。

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本发明涉及杀虫剂领域,具体地说是一种海藻内生真菌二萜生物碱类化合物及其制备和应用。具体结构式如(I)所示,其制备方法为将米曲霉(Aspergillus oryzae)cf-2接种于培养基中静止发酵,发酵液经乙酸乙酯萃取浓缩,菌丝体用有机溶剂提取,再经乙酸乙酯萃取浓缩,合并浓缩物,得到粗提物;粗提物进行硅胶柱层析,用有机溶剂进行梯度洗脱,收集洗脱液,洗脱液经薄层层析检测;将以洗脱液体积比10-15:1梯度的洗脱组分进行凝胶柱层析、硅胶柱层析和薄层层析分离纯化得目标化合物。本发明获得的海藻内生真菌二萜生物碱类化合物,经杀虫活性实验得出化合物在100微克/毫升时对卤虫的致死率为61.9%。

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本发明涉及杀虫剂领域,具体地说是一种海藻内生真菌二萜生物碱类化合物及其制备和应用。具体结构式如(I)所示,其制备方法为将米曲霉(Aspergillus oryzae)cf-2接种于培养基中静止发酵,发酵液经乙酸乙酯萃取浓缩,菌丝体用有机溶剂提取,再经乙酸乙酯萃取浓缩,合并浓缩物,得到粗提物;粗提物进行硅胶柱层析,用有机溶剂进行梯度洗脱,收集洗脱液,洗脱液经薄层层析检测;将以洗脱液体积比5-8:1梯度的洗脱组分进行凝胶柱层析、硅胶柱层析和薄层层析分离纯化得目标化合物。本发明获得的海藻内生真菌二萜生物碱类化合物,经杀虫活性实验得出化合物在100微克/毫升时对卤虫的致死率为42.9%。

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本发明涉及细菌抑制剂领域,具体地说是一种天然的海藻内生真菌二萜生物碱类化合物及其制备和应用。具体结构式如(I)所示,其制备方法为将米曲霉(Aspergillus oryzae)cf-2接种于培养基中静止发酵,发酵液经乙酸乙酯萃取浓缩,菌丝体先用有机溶剂提取,再经乙酸乙酯萃取浓缩,合并浓缩物,得到粗提物;粗提物进行硅胶柱层析,用有机溶剂进行梯度洗脱,收集洗脱液,洗脱液经薄层层析检测;将以洗脱液体积比0-10:100梯度,洗脱下的组分进行凝胶柱层析、硅胶柱层析和薄层层析分离纯化得目标化合物。本发明所得二萜生物碱类化合物具有显著的抑菌活性。

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本发明涉及杀虫剂领域,具体地说是一种海藻内生真菌次生代谢产物二萜生物碱类化合物的应用。所述海藻内生真菌次生代谢产物二萜生物碱类化合物具有杀虫作用,海藻内生真菌次生代谢产物二萜生物碱类化合物如式(I)所示;本发明通过分离于海洋红藻异管藻的真菌米曲霉(Aspergillus oryzae)cf-2发酵经提取、分离获得的二萜生物碱类天然化合物,经杀虫活性实验得出此二萜生物碱类化合物在100微克/毫升时对卤虫的致死率为74.2%。

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This work deals with adsorption of salt and expulsion of moisture in Synagris japonicus, Sciaenids sp. and Lactarius lactarius during prolonged salting. The fish used in this study were procured fresh and handled immediately. They were gutted, gilled, cleaned well and salted. Results indicated that larger salt proportions and higher temperature of salting both accelerate the rates of absorption of salt and shedding of moisture by fish muscle during salt curing.