慢性氨氮胁迫对台湾泥鳅幼鱼生长、免疫及组织结构的影响

以平均体质量为(2.00±0.56)g的台湾泥鳅(Paramisgurnus dabryanus ssp.Taiwan)幼鱼为研究对象,探究氨氮胁迫浓度为0、3.5、6.0、10.4和18.0 mg/L时台湾泥鳅幼鱼生长性能、免疫酶活性及组织结构的变化.经过56d的氨氮胁迫试验结果显示:台湾泥鳅终末体质量(WF)、增重...     

海洋红酵母多糖提取及其对日本蟳血清中部分免疫活性因子的影响

以海洋红酵母为材料, 通过化学抽提法得到多糖, 用经典的Sevag 法进行脱蛋白处理, 经多级沉淀得到纯糖并采用硫酸-蒽酮法测得其中葡萄糖含量; 考马斯亮蓝法分析蛋白质含量。以定量海洋红酵母多糖人工注射日本蟳, 注射等量生理盐水为对照, 定时测定其血清中部分免疫活性因子的活性; 实验表明: 提取多糖为蛋白多糖, 其中葡萄糖含量为3.6%, 蛋白质含量1.9%, 含有多种氨基酸, 其中天冬氨酸含量最多; 注射后12 h 日本蟳血清中总超氧化物歧化酶(T-SOD) 活力达到最高, 酸性磷酸酶(ACP) 活力在注射后24 h 达到最高, 碱性磷酸酶(AKP) 48 h 达到最高, 过氧化氢酶(CAT) 48 h 达到最高, 溶菌酶(LZM) 12 h 即达到最高, 最高点分别高于对照组24%、43%、25%、35%、95%; 72 h 后都恢复至对照组水平。结论: 海洋红酵母多糖注射48 h 内日本蟳体内免疫活性因子均有不同程度的提高, 对日本蟳有较强免疫刺激作用。     

盐胁迫对石蒜叶片形态结构和生理指标的影响

以石蒜为试材,测定了0.1、0.5、1.0mol/L NaCl胁迫下叶片的超氧化物歧化酶（SOD）和过氧化物酶（POD）的活性,可溶性蛋白、不溶性蛋白以及脯氨酸、丙二醛含量等生理指标的动态变化。用石蜡切片法对不同浓度NaCl胁迫后的叶片结构特征作比较,进行其抗盐性分析。结果表明：随NaCl浓度增加,对石蒜形态结构的影响表现在其叶片长度的变化及叶细胞的受损程度等方面;随NaCl浓度的增加和处理时间的延长,SOD和POD活性,不溶性蛋白、脯氨酸含量均呈先升后降趋势;可溶性蛋白呈先降后升趋势;丙二醛含量呈整体上升趋势。石蒜叶片各生理指标的变化通常在NaCl处理后的第7周和第8周为转折点。石蒜对低浓度的NaCl胁迫具有一定的耐受性。     

维生素E对青鱼幼鱼生长、免疫及抗氨氮胁迫能力的影响

以初始体质量(7.270.40) g的青鱼为研究对象, 采用维生素E(VE)有效含量分别为14.36(对照组)、25.14、37.66、62.97、113.92和210.45 mg/kg 6种等氮等能的实验饲料, 饲养青鱼幼鱼8周后, 根据生长情况选取对照组、62.97和210.45 mg/kg VE组进行24h氨氮胁迫(20 mg/L), 研究VE对青鱼幼鱼生长、免疫及抗氨氮胁迫能力的影响。结果表明: 以特定生长率为指标, 折线模型分析表明青鱼有效维生素E需要量为45.00 mg/kg。肌肉、肝脏和血清VE含量与饲料中VE含量呈明显正相关, 当饲料VE含量超过113.92 mg/kg时, 肌肉和肝脏VE含量均达到饱和。VE对鳃丝Na+/K+-ATP酶活性(NKA)和血清皮质醇(COR)无显著影响, 但随着饲料VE含量的升高, 过氧化氢酶(CAT)和总超氧化物歧化酶活性(T-SOD)呈上升趋势, 丙二醛含量(MDA)呈下降趋势。氨氮胁迫对各处理组肌肉VE含量和血清CAT活性无影响, 但肝脏VE含量均显著降低(P0.05), 且62.97和210.4 5 mg/kg VE组血清VE水平有所升高。在胁迫后, 对照组血清T-SOD、鳃丝NKA活性显著降低, 皮质醇含量显著增加(P0.05)。与对照组相比, 62.97和210.45 mg/kg VE组T-SOD、NKA活性和皮质醇含量在胁迫前后无显著变化。各处理组MDA含量在胁迫后虽均显著升高, 但210.45 mg/kg VE组在胁迫后MDA含量仍显著低于对照组(P0.05)。以上结果说明, 青鱼幼鱼获得最大生长的有效维生素E需求量为45.00 mg/kg, 且较高VE能有效提高青鱼机体免疫力, 缓解氨氮胁迫对青鱼机体的负面影响。       

干旱和盐胁迫对马铃薯试管苗亚细胞结构及生理生化指标的影响

以‘陇薯3号’脱毒试管苗为材料,研究了不同浓度PEG-4000(0、2%、4%、6%、8%)和NaCl(0、25、50、100、200mmol/L)对马铃薯2周大小试管苗根系生长、叶肉细胞超微结构及部分生理生化指标的影响,为筛选耐盐抗旱马铃薯种质提供理论依据。结果显示:(1)随着PEG-4000和NaCl浓度的增加,马铃薯试管苗根总长、根体积、根数均呈现下降趋势,并且胁迫浓度越高时间越长其下降趋势越明显,而盐胁迫处理的下降幅度明显大于PEG胁迫处理。(2)随着PEG-4000和NaCl浓度的增加,马铃薯试管苗叶肉细胞细胞壁明显变厚,发生明显的质壁分离,嗜锇颗粒显著增加,出现大量囊泡,叶绿体损害逐渐加剧,直至完全解体。(3)随着PEG-4000和NaCl浓度的增加,马铃薯试管苗脯氨酸(Pro)含量显著增加,过氧化氢(CAT)和超氧化物歧化酶(SOD)活性显著增强,而其丙二醛(MDA)含量迅速增加,但叶片叶绿素含量持续下降。研究表明,在PEG-4000模拟干旱和NaCl胁迫条件下,马铃薯试管苗叶片叶绿体结构受到严重损害,叶绿素含量显著降低,且胁迫程度越强损害越严重、下降幅度越大;同时,干旱和高盐胁迫也诱导马铃薯试管苗脯氨酸含量和抗氧化酶CAT和SOD活性显著上调,一定程度上缓解了干旱和高盐胁迫的伤害。     

NaCl胁迫对马蔺生长及生理生化指标的影响

采用水培法,以1/2Hoagland溶液为基础培养液,研究了1、2、3、4、6、8和10 g·L-1NaCl胁迫处理对马蔺[Iris lactea Pall.var.chinensis(Fisch.)Koidz.]幼苗部分生长和生理生化指标的影响.结果显示:随NaCl质量浓度的提高,马蔺幼苗的株高和根长、地上部分和根及全株干质量逐渐减小,但在1 g·L-1NaCl胁迫条件下,株高和地上部分及全株干质量均显著高于对照.随NaCl质量浓度的提高和胁迫时间的延长,马蔺幼苗叶片的相对电导率和丙二醛(MDA)含量总体上呈逐渐升高的趋势;其中,用1～4 g·L-1NaCl胁迫处理7或14 d,相对电导率有小幅增加但与对照差异不显著;用1～8 g·L-1NaCl胁迫处理7 d,MDA含量与对照差异不显著.叶片叶绿素和脯氨酸含量以及超氧化物歧化酶(SOD)活性则随胁迫时间的延长呈先升后降的趋势,在胁迫的14或21 d各指标达到最高值.随NaCl质量浓度的提高,脯氨酸含量和SOD活性均不断增加且总体上显著高于对照;叶绿素含量则随NaCl质量浓度的提高出现低浓度升高、高浓度降低的趋势,其中3和4 g·L-1NaCl胁迫处理组叶绿素含量最高;各处理组的可溶性蛋白质含量在处理的第7大或第14天与对照无显著差异,第21天则随NaCl质量浓度的提高呈低浓度升高、高浓度降低的趋势,而第28天则随NaCl质量浓度的提高逐渐降低.总体上看,低质量浓度和短时间的NaCl胁迫对马蔺生长和代谢的抑制作用不明显甚至略有促进作用,而高质量浓度和长时间的NaCl胁迫则具有明显的抑制作用.在实验结束后全部供试植株均存活,结合生长和生理生化指标的测定结果,初步判定马蔺对NaCl胁迫具有较强的耐性.     

不同浓度氨氮对轮叶黑藻的生理影响

在实验室条件下,比较研究了不同浓度（0.5、1、2、4、8、16mg/L）的氨氮（NH4＋-N）对沉水植物黑藻（Hydrilla verticillata）的生理生化影响,测定了黑藻生物量、叶绿素、可溶性糖、蛋白质含量和过氧化物酶（POD）、超氧化物歧化酶（SOD）、谷氨酰氨合成酶（GS）的活性变化。实验结果表明低浓度的氨氮（0.5、1、2mg/L）对轮叶黑藻的生长稍有促进作用,但培养液中氨氮浓度超过4mg/L时,黑藻的相对生长率（R）明显下降,当浓度达到16mg/L时,黑藻在20多天内全部死亡。在低浓度氨氮条件下,黑藻叶绿素和可溶性糖含量随氨氮浓度增加呈上升趋势,当培养液中氨氮浓度超过4mg/L时,叶绿素和可溶性糖含量在第24、32、40天取样时较对照组明显降低。低浓度氨氮处理组（0.5、1、2mg/L）的蛋白质含量先下降后又上升,而对照组的蛋白质含量一直在上升,高浓度氨氮处理组（8、16mg/L）的蛋白质含量则呈明显下降趋势。POD、SOD和GS活性变化趋势基本一致,在高浓度氨氮条件下增加显著,并表现为先上升再下降的格局,在第16天或第24天达到最大值。研究结果提示在富营养化条件下氨氮氨氮条件下增加显著,并表现为先上升再下降的格局,在第16天或第24天达到最大值。研究结果提示在富营养化条件下氨氮浓度的升高将影响其生理功能,过高浓度的氨氮对轮叶黑藻是一种逆境胁迫,可抑制其生长甚至导致植物死亡。轮叶黑藻对氨氮浓度变化虽有一定耐性,但耐性会随时间延长而变弱。     

低温胁迫对苜蓿幼苗存活及生理生化指标的影响

用秋眠级为2级至9级的11个苜蓿品种,每品种被随机分为对照组和5个处理组,研究低温胁迫和苜蓿品种对幼苗存活和叶片生理生化指标的影响。结果表明:低温胁迫和苜蓿品种对幼苗存活率、叶片生理生化指标的影响均极显著,而且二者对它们的互作效应也极显著。子叶期幼苗在-7.5℃下处理12 h,存活率仅为3.26%。幼苗在-5℃下处理12 h,存活率为54.73%,但叶片游离脯氨酸含量、过氧化物酶活性、质膜相对透性和根系活力极显著提高;每天把幼苗置于-5℃下2 h至3 h锻炼7天,幼苗存活率可提高到95%以上,叶片游离脯氨酸、可溶性糖、可溶性蛋白质含量,超氧化物歧化酶活性、根系活力和质膜相对透性均极显著提高。结果表明:4级至9级品种的存活率极显著低于2级至3级的品种;6级至9级品种叶片游离脯氨酸含量、过氧化物酶活性、质膜相对透性极著显低于2级至3级的品种。     

盐碱胁迫对欧李叶片部分生理生化指标的影响

以盆栽欧李为试验材料,研究了轻度、中度和重度盐碱胁迫下其叶片部分生理生化指标的变化,探讨欧李植株的耐盐碱能力.结果表明:(1)欧李叶片的MDA含量在轻度和中度盐碱胁迫处理下与对照变化趋势相似,而在重度胁迫下从开始即以较快的速度增加;其叶片细胞膜透性在中度和重度胁迫下明显增大,而轻度胁迫对此基本没有影响.(2)欧李叶片可溶性糖含量随盐碱胁迫处理而明显改变,叶片脯氨酸含量随着盐碱胁迫程度的增强和处理时间的延长而增加;叶片的束缚水/自由水在轻度和中度胁迫处理下较大,而重度胁迫处理下则较小.(3)欧李叶片的叶绿素含量在各盐碱处理末期均显著下降,但其在处理的不同阶段反应不同;类胡萝卜素含量受盐碱胁迫影响较大,其在长期盐碱胁迫下显著下降,但其在胁迫较轻或胁迫时间较短条件下反而增加.研究发现,欧李植株可通过调节叶片可溶性糖和脯氨酸含量以及束缚水/自由水比值来提高其耐盐碱能力.     

食物条件对日本蟳幼体存活与变态的影响

This paper studied the effects of different kind and density of baits and different starvation duration on Charybdis japonica larvae. The results showed that the preferable baits of zoaea-1 were Chaetoceros sp. and Isochysisgalbana, and their proper feeding density were 20 × 10^4 cell· ml^-1. The preferable bait of the larvae after zoaea-1 was Artemia salina nauplius, and its proper feeding density for zoaea-2 and zoaea-3 was 2 - 3 ind· ml^-1. The point of no-return for zoaea-1 of Charybdisjapoptica was about 66 hours. 18 hours starvation did not affect the growth of the larvae, but their livability would be decreased, and their metamorphism would be suspended along with the starvation duration.     

溶解氧对线纹海马幼鱼氨氮耐受性的影响及氨氮胁迫下鳃、肝脏组织结构的变化

为了解氨氮对线纹海马(Hippocampus erectus)幼鱼的毒理影响,本实验探讨了在正常溶解氧(4.32～5.12 mg·L-1)和高溶解氧(8.22～9.46 mg·L-1)条件下,线纹海马幼鱼的氨氮半致死浓度,以及6、9、12 mg·L-1的氨氮溶液胁迫下线纹海马幼鱼的鳃、肝脏组织结构的变化。结果表明:正常溶解氧条件下,氨氮对线纹海马幼鱼96 h半致死浓度(96 h LC50)为10.22 mg·L-1,安全浓度(SC)为1.02 mg·L-1;非离子氨的半致死浓度(96 h LC50)为0.16 mg·L-1,安全浓度(SC)为0.016 mg·L-1;高溶解氧条件下,氨氮对幼鱼的96 h LC50为12.68 mg·L-1,SC为1.27 mg·L-1;非离子氨96 h LC50为0.2 mg·L-1,SC为0.02mg·L-1。氨氮胁迫造成线纹海马幼鱼鳃组织在不同时间出现鳃丝血管扩张、泌氯细胞增生,鳃小片基部毛细血管破裂、红细胞溢出、鳃组织充血变性、卷曲变短、呼吸上皮细胞变性脱落等现象,并使肝脏肝细胞出现肿胀、细胞核肿大,肝血窦扩张、细胞轮廓模糊等组织变化;随着胁迫物...     

食物条件对日本幼体存活与变态的影响

This paper studied the effects of different kind and density of baits and different starvation duration on Charybdis japonica larvae. The results showed that the preferable baits of zoaea-1 were Chaetoceros sp. and Isochrysis galbana,and their proper feeding density were 20×10⁴ cell·ml^-1.The preferable bait of the larvae after zoaea-1 was Artemia salina nauplius, and its proper feeding density for zoaea-2 and zoaea-3 was 2～3 ind·ml^-1.The point of no-return for zoaea-1 of Charybdis japonica was about 66 hours. 18 hours starvation did not affect the growth of the larvae, but their livability would be decreased, and their metamorphism would be suspended along with the starvation duration.     

转Bt基因棉花对烟粉虱天敌昆虫龟纹瓢虫的影响

在实验室控制条件下,以转Bt基因棉花GK12、33B、SGK321上的烟粉虱为食料饲养龟纹瓢虫,研究转Bt基因棉花上的烟粉虱对龟纹瓢虫生长发育及捕食的影响,同时利用Y型嗅觉仪,观察龟纹瓢虫对来自不同类型棉花的棉叶及其烟粉虱的嗅觉反应和视觉反应。结果表明,转Bt基因棉花和对应的常规棉亲本上的烟粉虱对龟纹瓢虫的发育历期和存活率没有明显的影响。龟纹瓢虫对棉花叶片、烟粉虱若虫、蜜露、蜕等4种物质的视觉反应之间没有明显的差异。对4种嗅源物质的嗅觉选择性的大小依次为：烟粉虱若虫＞蜕＞棉花＞蜜露;在两类不同的棉花之间,转基因棉花和常规棉,龟纹瓢虫对GK12、33B、SGK321等三种转基因棉花上的烟粉虱若虫的嗅觉选择性明显较对应的常规棉亲本SM3、33、SY321上的烟粉虱若虫小;对烟粉虱若虫的蜕,两种转单价基因棉花GK12、33B较对应的常规棉亲本上的小,而转双价基因的棉花SGK321上与对应的常规棉之间没有明显的差异。烟粉虱密度大于200头.皿_-1时,龟纹瓢虫捕食转基因棉花上烟粉虱的数量大于对应的常规棉花亲本,但烟粉虱密度小于200头.皿_-1时,龟纹瓢虫捕食转基因棉花上烟粉虱的数量小于对应的常规棉花亲本。龟纹瓢虫对烟粉虱的捕食符合HollingⅡ型反应。龟纹瓢虫取食转基因棉花上的烟粉虱的理论极限值、瞬间攻击率均大于常规棉花。     

The external morphology and distribution of cuticular hair organs on the claws of the American lobster, Homarus Americanus (Milne-Edwards)

Four classes of microscopic cuticular hair organs were found on the chelae of Homarus americanus (Milne-Edwards). Type I and Type II organs possess long single sensillae, 30–60 μm and 70–130 μm, respectively. Type III organs are toroid bumps 20–30 μm in diameter, with a small tuft of fibers projecting from the center. Type IV organs are small conical hairs ≈ 1 μm in length.Type IV organs were uniformly distributed over the claws. The distributions of Types I, II, and III organs were analysed through multivariate analysis of variance (MANOVA) with respect to claw, side, and area. Type I organs showed significance of the three-way interaction only. Type II organs showed significance of side, area, and the claw by area interaction. Type III organs showed significance of area, and all interactions. Changes in number and density of Types I, II and III organs, and in number of Type IV organs, were found with growth.     

外源钙（Ca）对毛葱耐镉（Cd）胁迫能力的影响

以对环境敏感的毛葱(Allium cepa var.agrogarum L.)为材料,通过水培试验分别研究不同浓度Ca(0、0.1、1、10 mmol/L)对Cd(10μmol/L、100μmol/L和300μmol/L)胁迫下毛葱幼苗生长、叶片光合特性、体内Cd积累和矿质营养的变化,探讨Ca缓解敏感植物Cd毒害的生理生化机制。结果表明:(1)Cd显著抑制了毛葱的生长并导致其根端弯曲、发黄,叶片绿色加深;外源Ca显著削弱了Cd的毒害,缓解了其对毛葱生长的抑制;(2)Cd导致毛葱叶片光合色素含量大幅度上升却显著降低了毛葱的光合作用;外源Ca延缓了光合色素上升的速度,提高了毛葱的净光合速率、气孔导度和蒸腾速率;(3)Cd胁迫导致毛葱体内Cd含量显著增加,并造成明显的矿质营养失衡,主要表现为显著降低了毛葱根中Mg、Mn,叶中Ca、Mg、Mn、Zn等元素的含量,毛葱根中Ca、Fe、Zn,叶中Fe元素含量的显著增加,扰乱了毛葱体内矿质营养的内稳态;外源Ca削弱了毛葱对Cd的积累,减轻了Cd胁迫所造成的矿质营养失衡。因此,外源Ca能通过抑制Cd的吸收,促进叶片光合作用及气体交换速率,维持植物体的含水量、植物叶片光合色素含量及矿质营养的平衡等途径来增强毛葱对Cd胁迫的耐性。     

Dipetalonema viteae: Effects of hypo- and hyperthermic stress on microfilaremia in the Mongolian jird, Meriones unguiculatus

The effects of thermal stress on the numbers of circulating microfilariae of the filariid parasite, Dipetalonema viteae, in its host, the Mongolian jird, Meriones unguiculatus, was determined. The microfilaremia of each animal was allowed to stabilize, and the effects of stress were measured from this level. The ambient temperature was raised or lowered in 5C increments and maintained at each increment for a 24-hr period. Deep core body temperature of the jirds was recorded by the use of telemetry transmitters placed in the abdominal cavity. The transmitter signals were recorded on a Dynograph recorder. Blood samples were drawn at 0, 12, and 24 hr exposure to each ambient temperature, and microfilariae counted. Microfilaremial levels were then compared to numbers circulating prior to thermal stress. Both hypothermia and hyperthermia in the jird resulted in increased numbers of microfilariae in the peripheral blood. It is speculated that these fluctuations are changes in the percentage of the total microfilarial pool, and represent fluctuations of larvae being driven out of tissue and deep circulatory channels.     

Histological structure of the female gonads and ovipositor of the European bitterling,Rhodeus amarus (Bloch, 1782) (Cyprinidae: Acheilognathinae)

We investigated the histological structure of the female gonads and ovipositor of the European bitterling, Rhodeus amarus. The base of the ovipositor was formed by the conical organ or ‘eminence’. Based on the structure of the conical organ, including a special distribution of collagenous and muscular fibrils, a well‐developed vascular system and numerous scyphoid mucous cells in the internal epithelium, this organ was used for temporary storage of oocytes during the spawning period and for their movement along the ovipositor. An extensive network of blood vessels, muscular fibrils and numerous collagenous fibrils in the connective tissue of the ovipositor may make a functional contribution to the ovipositor by making it firmer during egg laying. Mucous cells were detected in the medial and distal regions of the ovipositor, which may play a role in facilitating insertion of the ovipositor into the exhalant siphon of a mussel during oviposition. European bitterling are batch spawners, and the female spawns eggs in clutches at intervals during the breeding season, which were visible as three distinct cohorts of oocytes in the ovary.     

Burrow structure and use in the sand fiddler crab, Uca pugilator (Bosc)

Uca pugilator, the sand fiddler crab, constructs two kinds of burrows in protected, sandy upper-intertidal and supratidal substrates on the west coast of Florida. Temporary burrows are built and used as a refuge by non-breeding crabs during high tide periods and at night when crabs cease feeding in the intertidal zone. Breeding burrows are constructed and defended by courting males and are the site of mating, oviposition and the incubation of eggs by females. Up to three ovigerous females may be accommodated in a single breeding burrow, each female sequestered in a separate terminal chamber. The construction and defence of burrows specialized for breeding may be an adaptive response by males to the preferences females exhibit when selecting a breeding site.     

Physiological, anatomical and phenotypical effects of a cadmium stress in different-aged chlorophyllian organs of Myriophyllum alterniflorum DC (Haloragaceae)

Cadmium stress on aquatic macrophytes is currently few documented and no studies were conducted on clonal populations in controlled conditions. Our aim is to assess the effect of cadmium stress on Myriophyllum alterniflorum from physiological, anatomical and phenotypical parameters among different developmental stages. An experiment was carried out in order to test the hypothesis that a high external dose of Cd affects differentially young and old leaves of watermilfoil in terms of (1) anatomical and biological parameters, (2) physiological parameters and (3) that these differences result from the overall level of oxidative stress. Cadmium stress strongly affects the morphology of chlorophyllian organs and decreases the xylem-vessel number and diameter in matures leaves. Moreover we first report a new cadmium-induced anatomical feature: a double endodermis with separated layers which limits water and gaseous losses in mature leaves. From a physiological point of view, cadmium induces at all developmental stages a reduction in chlorophyll contents, a malondialdehyde production indicating a drastic lipoperoxydation, an enhanced production of reactive-oxygen-species scavengers (free proline and in lesser parts carotenoids) and a perturbation in hydric status in M. alterniflorum clones. The results obtained support the initial hypotheses. Indeed, it should be noted that cadmium stress mainly disturbs mature-leave structure and function, increasing their ageing and senescence. This mechanism probably contributes to limit the cadmium impact on young and growing parts as cadmium is known to preferentially accumulate in senescent leaves.