纤维素对海洋细菌生物被膜形成及厚壳贻贝幼虫附着变态的调控

为探讨纤维素对假交替单胞菌属细菌等在生物被膜形成过程中的生物量和胞外产物的影响,以及生物被膜等生物学特性的改变对海洋无脊椎动物幼虫附着变态的影响,选取对厚壳贻贝Mytilus coruscus幼虫附着变态具有高诱导和中等程度诱导活性的海洋细菌Pseudoalteromonas atlantica、Shewanella loihica,分析了纤维素在细菌生物被膜形成过程中和生物被膜形成后,对生物被膜特性,如细菌密度、膜厚、胞外产物等的影响,以及生物被膜对厚壳贻贝幼虫附着变态的调控作用。结果表明:纤维素对厚壳贻贝幼虫的附着变态无显著性影响(P0.05),而纤维素与细菌共同形成的生物被膜及纤维素处理的生物被膜对幼虫附着变态的诱导活性均显著下降(P0.05);通过对生物被膜的特性分析发现,两种纤维素添加方式处理的生物被膜,与野生型单一生物被膜相比,细菌量均明显减少,膜厚降低,胞外多糖、胞外脂含量减少,而胞外蛋白无显著变化(P0.05)。研究表明,纤维素可通过调控细菌生物被膜的细菌密度、膜厚和胞外产物等特性,最终影响厚壳贻贝幼虫的附着变态。     

双齿围沙蚕的生活史

为系统了解双齿围沙蚕Perinereis aibuhitensis的生活史,通过人工培育方法观察了其胚胎和幼虫发育全过程,并通过解剖观察了卵的发生及正常个体变态为生殖态异沙蚕体的过程。结果表明:双齿围沙蚕的受精卵采取螺旋型卵裂,形成实心囊胚,经原肠胚后发育为担轮幼虫、疣足幼虫、稚沙蚕和成体沙蚕;卵的发育在体腔内经历卵原细胞期、小生长初级卵母细胞期、大生长初级卵母细胞期和成熟初级卵母细胞期后排出体外,并在受精后进一步形成次级卵母细胞和卵细胞;当正常个体变态为异沙蚕体时,会发生体长明显缩短、腹部变白、眼睛变大和疣足变薄等变化,异沙蚕体繁殖后死亡;研究过程中还观察到幼虫循环系统的发生和红斑等现象。本研究结果可为全面掌握双齿围沙蚕的生活史及开展人工养殖业提供基础数据。     

瘤背石磺的胚胎和幼虫发育

在水温27～29℃、气温27～31℃和海水盐度为16的环境条件下人工孵化瘤背石磺的卵块,根据早期发育的形态变化将其划分为胚胎发育(包括卵裂期、囊胚期、原肠期、卵内担轮幼虫、卵内面盘幼虫)和幼虫发育(包括开口期、大面盘幼虫、附着期、匍匐幼虫)两个阶段。受精卵发育至卵内担轮幼虫需要51h,胚胎发育89h后变态为卵内面盘幼虫,第7天面盘幼虫孵化出卵,直径增大1倍;第23天幼虫变态为匍匐幼虫,虫体直径为受精卵的4倍。分析认为,瘤背石磺的胚胎发育具备典型的不等全裂、螺旋卵裂特征,幼虫为典型的腹足纲面盘幼虫形态;温度对胚胎发育时间影响显著而充气可以加速幼虫孵化出卵;面盘幼虫需要有适宜的潮间带环境和饵料(如底栖硅藻)才可以正常附着变态。     

瘤背石磺的胚胎和幼虫发育

在水温27～29℃、气温27～31℃和海水盐度为16的环境条件下人工孵化瘤背石磺的卵块,根据早期发育的形态变化将其划分为胚胎发育(包括卵裂期、囊胚期、原肠期、卵内担轮幼虫、卵内面盘幼虫)和幼虫发育(包括开口期、大面盘幼虫、附着期、匍匐幼虫)两个阶段。受精卵发育至卵内担轮幼虫需要51h,胚胎发育89h后变态为卵内面盘幼虫,第7天面盘幼虫孵化出卵,直径增大1倍;第23天幼虫变态为匍匐幼虫,虫体直径为受精卵的4倍。分析认为,瘤背石磺的胚胎发育具备典型的不等全裂、螺旋卵裂特征,幼虫为典型的腹足纲面盘幼虫形态;温度对胚胎发育时间影响显著而充气可以加速幼虫孵化出卵;面盘幼虫需要有适宜的潮间带环境和饵料(如底栖硅藻)才可以正常附着变态。     

南麂海区养殖贝类的附着生物及其防除研究

2004年7-11月,对南麂马祖岙海区养殖的太平洋牡蛎、海湾扇贝和厚壳贻贝的附着生物进行采样调查,分析了附着生物的种类组成、垂直分布、栖息密度、生物量及波动特征。结果表明,附着生物共有41种,隶属于9个生物门,其中节肢动物有10种,为最多;锯额豆瓷蟹、三角藤壶垂直分布最广;主要优势种为三角藤壶、牡蛎等,不同养殖贝类有不同的优势种;养殖贝类的外部形态与附着生物的附着效果有较大的关系,附着生物对附着体有一定的选择性,台风对附着生物的附着有较大的影响。同时,对在养殖生产中可利用改变吊挂水层、错开附着时间、使用药物等防除措施进行了探讨。     

船体藤壶附着模型的建立及清除藤壶的仿真研究

藤壶是中国周边海域一种常见的海洋污损生物,具有黏接强度高、难清除的特点.利用COMSOL Multiphysics软件建立藤壶附着的模型,模拟藤壶附着船体的情况并对其进行力学仿真研究,得到了达到清除效果时藤壶胞外分泌胶体的应力、应变以及应变能等数值模拟数据.本研究表明,当提供的外力(清除力)达到180 N时,该仿真模型中藤壶有被清除的趋势,模拟胞外分泌物(EPS部分)的应力强度约为0.2MN/m2,该胶体的黏性应变能为0.29 J/m3,在该模型中得出的清除藤壶所需力的数据与其他文献发表的实验结果基本相符,该模型可用于后续用强声法清除附着藤壶的仿真研究.     

紫海胆肠道真菌Aspergillus sp.HDf2次生代谢产物抗生物污损活性的研究

[目的]对紫海胆肠道曲霉菌Aspergillus sp.HDf2的次生代谢产物进行抗海洋生物污损活性研究。[方法]采用摇瓶液体发酵,运用柱层析等方法,从发酵液中分离、纯化获得4个γ-丁烯酸内酯类单体化合物(-)-spiculisporic acid、spiculisporic acids B–D和1个secospiculisporic acid B,并且对其进行了抗藤壶幼虫附着活性测试。[结果]化合物spiculisporic acid B和secospiculisporic acid B在浓度为25 mg/L时均具有抗藤壶幼虫附着活性,其中化合物secospiculisporic acid B活性最强,其他化合物无活性。[结论]该研究首次报道它具有抗生物污损活性。     

3种滩涂贝类稚贝附着基和多层附苗技术的初步研究

2002年3～8月对菲律宾蛤仔Ruditapesphilippinarum、青蛤Cyclinasinensis和硬壳蛤Mercenariamercenaria3种滩涂贝类的变态附着基和多层附苗技术进行了试验研究。附着基分别采用黑色波纹板、透明波纹板、筛绢、塑料薄膜、扇贝养成笼托盘、扇贝网片和细砂7种。结果表明,不同附着基间的贝类幼虫附着变态效果差异极显著(p<0 01),波纹板(黑色和透明)和塑料薄膜是3种滩涂贝类的适宜附着基,幼虫的变态率最高。采用多层结构的附着基附苗(多层附苗技术)效果均优于细砂(p<0 05),用多层附着基可以提高单位水体附着面积和出苗量,单位水体附着面积扩大了2 17～2 75倍,单位水体出苗量提高了1 19～4 30倍。此外,于7月8日至8月24日以透明波纹板为附着基,采用多层附苗技术对硬壳蛤幼虫附着变态进行了中试,稚贝的变态率达66 7%,生长速度为90 09μm/d,变态后49d的成活率达90%以上,室内培育的稚贝平均壳长达4 62mm,数量约1000万枚。     

辛基酚对家蚕（Bombyx mori L.）生长发育的影响

为探讨辛基酚对鳞翅目模式昆虫家蚕生长发育的影响,使用添加0.01～0.08 g·kg~(-1)辛基酚(4-tert-octylphenol,4-t-OP)的人工饲料饲养家蚕(Bombyx mori L.),研究了4-t-OP对家蚕幼虫和蛹的生长发育速度、生长量、发育整齐度和生命力等影响。结果表明:连续取食0.01 g·kg~(-1)以上浓度4-t-OP的饲料,家蚕幼虫和蛹的生长发育速度(幼虫期和蛹期发育经过时间)、生长量(幼虫期体质量和蛹期茧层量)、生命力(3龄起蚕绝食生命时数、4龄起蚕结茧率、蚕茧的死笼率和羽化率)等都明显下降,抑制眠蚕体质量。4-t-OP对家蚕幼虫生长发育后期、化蛹及羽化等发育变态期的影响更加明显,其在家蚕体内可能有累积效应。添食0.08 g·kg~(-1)4-t-OP的家蚕不能完成生活史。研究表明,4-t-OP对家蚕生长发育毒性影响有显著的浓度效应和时间效应。     

海洋污损生物藤壶的附着机理及防除

藤壶是东海区主要的污损生物之一。阐述了藤壶污损海上设施的危害，并从藤壶的生物结构、生活环境等方面分析了藤壶的粘附机理，以及影响藤壶附着的多种因素，并介绍了有关防止藤壶污损的环保型挂海试验效果。     

Pheromonal Control of Metamorphosis in the Pacific Sand Dollar, Dendraster excentricus

Competent larvae are induced to undergo metamorphosis by sand from a sand dollar bed or an aqueous extract of the sand. Gel permeation chromatography and high-performance liquid chromatography of the extract yielded a 980-dalton peptide that will induce metamorphosis between 10(-6) and 10(-5) molar. Extracts of whole adults and gonads were also able to induce metamorphosis, and adults can condition substrates to induce metamorphosis. Therefore, the initiation of metamorphosis in Dendraster excentricus is controlled by a pheromone released by adult sand dollars.     

Partial metamorphosis in Anomia simplex

Many larvae of the common bivalve, Anomia simplex, when grown under laboratory conditions, exhibited a partial metamorphosis. They attained a considerably larger size than that at which larvae normally set. The partial metamorphosis was also characterized by the disappearance of velum, but the retention of a functional foot. Moreover, these organisms were not able to attach to the substratum, and their shells showed a distinct demarcation line between larval and adult portions     

北方沿海翡翠贻贝人工育苗技术研究

于2011、2012年,在大连对翡翠贻贝Perna viridis室内人工育苗技术进行了初步研究,成功培育出壳长为4.5～10.0 mm的稚贝6 500万个。比较了不同培育密度(5、10、15、20、30、50个/mL)和饵料种类(小球藻、湛江等鞭金藻和小球藻与湛江等鞭金藻的混合饵料)对翡翠贻贝幼虫生长的影响,并分析了在4种附着基(聚乙烯网片、波纹板、聚乙烯网衣、聚乙烯吊绳)和无附着基条件下的采苗效果。结果表明:随着培养密度的增大,幼虫生长速度下降,存活率减小,变态率降低,变态时间延迟;在室内幼虫培育期间,用小球藻与等鞭金藻的混合饵料比单一饵料的投喂效果理想,单一饵料投喂中等鞭金藻效果较好;在幼虫变态过程中,聚乙烯网片的采苗效果最理想,其次为波纹板,无附着基的采苗效果最差。     

一种软苔虫(Alcyonidium sp.)胚胎及幼虫发育的初步观察

我们在鲍鱼养殖笼内采集到一种软苔虫(Alcyonidium sp.),通过室内低温培养的方法,对其胚胎和幼虫进行了研究,观察了它的精卵的形态、受精卵的发育、浮游幼虫的形态及其趋光和趋地性变化、幼虫的附着和变态。     

Dual origin of tissue-specific progenitor cells in Drosophila tracheal remodeling

During Drosophila metamorphosis, most larval cells die. Pupal and adult tissues form from imaginal cells, tissue-specific progenitors allocated in embryogenesis that remain quiescent during embryonic and larval life. Clonal analysis and fate mapping of single, identified cells show that tracheal system remodeling at metamorphosis involves a classical imaginal cell population and a population of differentiated, functional larval tracheal cells that reenter the cell cycle and regain developmental potency. In late larvae, both populations are activated and proliferate, spread over and replace old branches, and diversify into various stalk and coiled tracheolar cells under control of fibroblast growth factor signaling. Thus, Drosophila pupal/adult tissue progenitors can arise both by early allocation of multipotent cells and late return of differentiated cells to a multipotent state, even within a single tissue.     

马桑籽提取物对黑肩毛胸榆叶甲取食及生殖的影响

马桑种子提取物对黑肩毛胸榆叶甲成虫及幼虫具有明显的拒食作用，其拒食中浓度（ＡＤＣ（５０））分别为０．０４３６ｋｇ籽／Ｌ、０．０４０５ｋｇ籽／Ｌ。并能明显地改变雌成虫的生殖行为，极大地缩短雌成虫的寿命，降低其产卵量（在０．０４３６ｋｇ籽／Ｌ处理条件下较对照下降２５．９８％）。研究结果还表明，马桑籽提取物对该虫的卵有杀伤作用，其致死中浓度（ＬＣ（５０））为０．１１７１ｋｇ籽／Ｌ。     

A larval specific OBP able to bind the major female sex pheromone component in Spodoptera exigua(Hübner)

Odorant binding proteins(OBPs) in insects are postulated to solubilize and transport the hydrophobic odorants across the hydrophilic antennal lymph to the olfactory receptors(ORs) located on the dendrite membrane of the sensory neurons. OBPs in adult insects have been intensively reported, but those in larvae are rarely addressed. In our study, a full-length OBP c DNA, namely Sexi OBP13, was cloned by RT-PCR and RACE strategy from the heads of Spodoptera exigua larvae. The quantitative real-time PCR(q PCR) measurement indicated that Sexi OBP13 was highly expressed in larval head, but very low in other parts of larva and was not detected in any tissues of adult. The binding affinities of Sexi OBP13 to plant volatiles and female sex pheromone components were measured by competitive binding assays. Interestingly, Sexi OBP13 displayed a high binding affinity(Ki=3.82 μmol L–1) to Z9,E12–14:Ac, the major sex pheromone component of S. exigua, while low affinities to the tested host plant volatiles(Ki27 μmol L–1). The behavioral tests further confirmed that Z9,E12–14:Ac was indeed active to elicit the behavioral activity of the third instar larvae of S. exigua. Taken together, our results suggest that Sexi OBP13 may play a role in reception of female sex pheromone in S. exigua larvae. The ecological significance of the larvae preference to the adult female sex pheromone was discussed.     

枣粘虫成虫性引诱的初步研究

枣粘虫是我国红枣产区的重要害虫。为探求防治新途径,对成虫生物学与性引诱进行了初步研究。枣粘虫一年发生三代,各代成虫发生的始、盛、末期分别为:第一代3/上——4/上—4/下;第二代6/上——6/中——6/下;第三代7/上——7/下——8/中。雌雄性比在0.86∶1和1.19∶1之间。一般雄蛾羽化早於雌蛾。95％以上成虫集中于早晨5——8时进行交尾。雌雄多次交尾,雌蛾平均1.48次,雄蛾3次。成虫寿命一般为一周左右,雌蛾寿命长於雄蛾。田间性诱试验表明:活雌蛾性诱以3头和5头的雌当量效果最好;粗提液以乙醚为溶剂的诱蛾数量最高;摘取腺体以羽化后48小时摘取的诱捕效果较好。通过对雌蛾性腺体所产生的性信息素进行EAG——GC以及色质联仪分析,初步确定枣粘虫性信息素的成份是一元不饱和十二碳烯醇乙酸酯的多元体系。经微量臭氧化测定,双键位置在7位和9位。田间生测表明以反、顺——9——十二碳烯醇酯(E、Z——9—C_(12)∶OAC)在比例为80∶20和83∶17时对雄蛾的诱捕效果最高。     

Prevention of metamorphosis by exposure of insect eggs to juvenile hormone analogs

Metamorphosis of the bugs Pyrrhocoris apterus and Oncopeltus fasciatus is blocked by the application of juvenile hormone analogs to the eqgs 4 weeks earlier. One or more supernumerary larval molts occur to form "giant" larvae which routinely die without undergoing netamorphosis. When the corpora allatta were excised at the outset of the fifth larval stage, the entire phenomenon vanished and all individuals underwent normal metamorphosis. The inhibition of metamorphosis can therefoore be attributed to a continuation of the secretion of endogenous juvenile hormone by the corpora allata of mature larvae deried from eggs treated with juvenile hormone.