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1.
IntroductionTheoccurrenceofAsianduststorms(ADS)iscommonduringthemonthsoflatewinterandspringinEastAsia.Underfavorablesynopticconditions,significantamountsoftheAsiandustmaybetransportedtoTaiwan(Chen&Chen1987).Inrecentyears,ADSoverTaiwanreceivedsubstantialattentionbecauseoftheirimpactontheairquality.Besideshigherconcentrationsofmineralelements,highlevelsofanthropogenicspeciessuchassulfateandnitratehavebeenobservedintheoutflowfromtheAsiancontinent(Clarkeetal.2001).Thus,inthiswork,theinfluen… 相似文献
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Genetic diversity and relatedness estimates for captive barramundi (Lates calcarifer,Bloch) broodstock informs efforts to form a base population for selective breeding 下载免费PDF全文
Shannon R Loughnan Carolyn Smith‐Keune Dean R Jerry Luciano B Beheregaray Nicholas A Robinson 《Aquaculture Research》2016,47(11):3570-3584
Aquaculture of barramundi or Asian seabass (Lates calcarifer) is growing in both Australia and Southeast Asia and there is substantial interest to improve production efficiency through selective breeding. The establishment of a large and genetically diverse base population is a prerequisite for a sustainable and long‐term productive breeding program. Before selective breeding programs can begin for Australian barramundi it is important to assess the overall genetic diversity of current captive broodstock populations. To address this question, 407 captive barramundi broodstock from eight separate Australian broodstock populations were genotyped using 16 polymorphic microsatellite DNA markers. A Bayesian STRUCTURE analysis indicated that captive Australian broodstock are broadly divided into two genetic stocks. Multivariate analysis between broodstock individuals and pairwise FST between broodstock populations also supported the existence of two stocks. Comparisons with data obtained from natural stocks suggested that hatchery individuals were either sourced from the two stocks or represented an admixture between them. Genetic diversity was low within each broodstock population (allelic richness ranged from 2.67 to 3.42 and heterozygosity ranged from 0.453 to 0.537) and relatedness estimates within hatcheries were generally low (average r was equal to 0.141). We recommend sourcing captive individuals according to high levels of neutral genetic diversity and low levels of relatedness for the establishment of a base population. We also make recommendations about including genetically diverse wild individuals. 相似文献
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寄主植物对亚洲玉米螟取食、生长发育和生殖的影响 总被引:8,自引:3,他引:8
本文对亚洲玉米螟在甜玉米、饲料玉米、无毒棉和有毒棉上的取食、生长发育和生殖作了比较研究。结果表明:初孵幼虫嗜食无毒棉棉叶,3龄幼虫则喜食玉米心叶。5龄幼虫在甜玉米上的取食次数最多,取食总时间最长,在有毒棉上的取食时间最短。5日龄以前,取食无毒棉的幼虫生长最快,而后取食玉米的幼虫生长加快;取食有毒棉的幼虫生长最慢,其老熟幼虫的体重仅为取食甜玉米的1/3。取食棉花的幼虫历期明显延长,虫龄增加至6龄。幼虫期存活率、蛹重和每雌产卵量以甜玉米为最高,依次为饲料玉米、无毒棉和有毒棉。试验证明,在扩种甜玉米和无毒棉以后亚洲玉米螟种群将上升。 相似文献
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舞毒蛾是一种世界性的害虫,常被分为欧洲型和亚洲型2种类型,欧洲型舞毒蛾在传入美国之后造成了巨大危害。之前报道指出亚洲型舞毒蛾的寄主范围比欧洲型舞毒蛾的广,故造成的危害和损失更大,北美植物保护组织据此对中国的高风险港口实施了船舶特别检疫措施,对我国的进出口贸易产生了巨大影响。鉴于此,本实验以16种北美和中国常见的行道树种和绿化树种作为供试树种,分析了不同寄主植物对亚洲型舞毒蛾生长发育指标的影响规律。结果表明:饲喂白桦、加杨和糖槭的幼虫可以完成生活周期。饲喂杜松、女贞、大叶黄杨、红皮云杉、合欢、杂交鹅掌楸、马尾松、黑松和白皮松的幼虫在2龄以前全部死亡。虽然2龄以前幼虫饲喂北美乔松、油松和柿树后死亡率较高,但用人工饲料将幼虫饲养至4龄以后再替换饲喂以上3种植物,幼虫的死亡率则显著下降。分析表明,亚洲型舞毒蛾低龄幼虫(1、2龄)的寄主选择范围要窄于高龄幼虫(4龄以后的幼虫)。 相似文献
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亚洲玉米螟颗粒体病毒利用研究 总被引:2,自引:0,他引:2
从亚洲玉米螟幼虫体内分离出一株“OFGV—01”病毒,该病毒颗粒体卵圆形,大小为295~356nm×250~305nm,平均为325.5nm×277.5nm。病毒粒子杆状,两端钝不弯曲或稍弯曲,大小为200~256nm×185~196nm,平均为228nm×190.5nm。该病毒对亚洲玉米螟幼虫致病力较强,在温度24~26℃,相对湿度73%~78%条件下,对3日龄、6日龄幼虫感病4~6天死亡率分别达100%和98.3%,9日龄、10日龄幼虫第8~9天死亡率分别为85.5%和83.5%。利用该病毒于山西省太谷县、祁县、榆次市田间防治亚洲玉米螟幼虫,防治效果一般为80%~85%.高的可达90%。该病毒对天敌无杀伤作用,对小白鼠(昆明种)、大白鼠(Wismr 种)、家免和豚鼠无致病性。 相似文献
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Trophic relationships and ecosystem characteristics in a newly-impounded man-made lake in Thailand 总被引:1,自引:0,他引:1
T. THAPANAND T. JUTAGATEE P. WONGRAT T. LEKCHOLAYUT C. MEKSUMPUN & S. JANEKITKARN A. RODLOI J. MOREAU & L. WONGRAT 《Fisheries Management and Ecology》2009,16(2):77-87
Abstract The trophic dynamics of a newly-impounded south east Asian reservoir, Pasak Jolasid, Thailand, monitored from its creation, were constructed using ecopath , a mass-balanced model. The trophic levels (TLs) of 36 ecological groups varied between 1.0 and 3.2. The majority of fish biomass was at the second TL, where the fishery is concentrated. Some food resources (benthic organisms and zooplankton) were not fully used, whereas phytoplankton and benthic algae were important components of the food web, which is based on phytoplankton and detritus. The implications of these findings are discussed in terms of ecological maturity of the ecosystem and possible fishery management of this multi-purpose reservoir. 相似文献
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Dietary levamisole modulates the immune response and disease resistance of Asian catfish Clarias batrachus (Linnaeus) 总被引:2,自引:0,他引:2
In order to determine the immunomodulatory effect of dietary levamisole in Asian catfish (Clarias batrachus), fish were fed four different diets for 10 days: a formulated diet as control and the same diet supplemented with 50, 150 or 450 mg levamisole kg?1 feed. The serum bacterial agglutination titre against Aeromonas hydrophila as a measure of specific immunity, serum haemagglutination titre, natural haemolytic complement activity (ACH50), myeloperoxidase and lysozyme activities, total protein level and oxidative radical production by neutrophils as a measure of non‐specific immunity as well as disease resistance against A. hydrophila challenge to separate vaccinated and non‐vaccinated groups were evaluated at 0, 1, 2 and 3 weeks after last administration of levamisole. Levamisole supplement at the lowest level (50 mg kg?1) significantly enhanced oxidative radical production and serum myeloperoxidase (MPO) content immediately after 10 days of feeding, which reached peak values after 3 and 2 weeks of feeding respectively. Haemolytic complement and haemagglutination titre were significantly enhanced after 3 and 1 weeks respectively. Haemolytic complement activity and MPO activities were significantly raised to 150 mg kg?1 after 3 and 2 weeks, respectively. At the highest level of levamisole feeding (450 mg kg?1) significant decreases in superoxide production and complement activity were measured immediately after levamisole feeding, which returned to the normal level after 1 week post‐ feeding. Fish were challenged with a virulent strain of A. hydrophila at 0, 1, 2 and 3 weeks after levamisole feeding, and the cumulative per cent survival was recorded over 10 days. Feeding levamisole at 50, 150 or 450 mg kg?1 increased per cent survival in vaccinated fish immediately after levamisole feeding, and survival was significantly higher at 450 mg kg?1. There was no difference in mortality patterns in non‐vaccinated fish. The results support the use of levamisole at 50 mg kg?1 feed for 10 days as an immunostimulant in Asian catfish farming. 相似文献
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