异色瓢虫显明变种对荻草谷网蚜和禾谷缢管蚜捕食选择性研究

在实验室条件下,在特定空间内,测定异色瓢虫显明变种对两种蚜虫荻草谷网蚜和禾谷缢管蚜不同密度值下的捕食量。结果表明,荻草谷网蚜和禾谷缢管蚜种群数量同步增加时,EG-S值和EI值变化是从1到∞,EI值是在0到+1范围内依次增加,表明异色瓢虫显明变种喜好捕食荻草谷网蚜明显高于禾谷缢管蚜;荻草谷网蚜数量不变,禾谷缢管蚜数量增加时,EG-S值和EI值是从+1到0,EI值从-1到0范围内依次减少,表明异色瓢虫显明变种明显喜好捕食禾谷缢管蚜;禾谷缢管蚜数量不变,荻草谷网蚜数量增加时,EG-S值和EI值变化从+1到∞,EI值在0到+1范围内依次增加,表明异色瓢虫显明变种明显喜好捕食荻草谷网蚜。捕食量结果同选择指数。     

3种饲料对异色瓢虫生长发育的影响

为筛选异色瓢虫的适宜饲料,观察比较了菜缢管蚜、麦蛾卵和人工饲料对异色瓢虫生长发育的影响。结果显示:菜缢管蚜饲养的异色瓢虫发育最快,世代历期为25.3d,产卵前期为11.0d,平均单雌产卵量为929.3粒;麦蛾卵饲养的世代历期为39.5d,产卵前期为18.2d,平均单雌产卵量为391.9粒;人工饲料饲养的世代历期为44.9d,产卵前期为17.2d,平均单雌产卵量为262.3粒。由此表明,菜缢管蚜的饲养效果最好,麦蛾卵和人工饲料虽能满足异色瓢虫世代营养的需求,但发育历期明显延长、产卵量明显下降。因此,在天然食物蚜虫不足时,麦蛾卵和人工饲料可作为补充饲料。     

Correlations between phytohemagglutinin response and leukocyte profile,and bactericidal capacity in a wild rodent

phytohemagglutinin (PHA)‐induced swelling is widely used to investigate cell‐mediated and innate immunity across different vertebrate taxa. However, its physiological mechanism is still an open question due to the complexity of the involved immune components. In the present study, we measured the synchronous variations of PHA response, the proportion of different subtypes of leukocytes, as well as serum bactericidal capacity in circulation blood at 6, 12 and 24 h after PHA versus PBS injection in striped hamster, Cricetulus barabensis. First, the results showed that PHA responses reached a peak at 6 h postinjection, then sharply declined at 12 h and 24 h postinjection. Serum bactericidal capacity was higher at 6 h and 12 h than at 24 h. The proportion of different subtypes of leukocytes, as well as the ratio of neutrophils to lymphocytes did not display significant changes across different time points. Second, PHA response was positively correlated with the proportion of neutrophils and serum bactericidal capacity. The proportion of monocytes was negatively correlated with that of eosinophils and neutrophils. The proportion of basophils was negatively correlated with that of lymphocytes. Our results indicate that earlier enhanced PHA response is important for the striped hamster to cope with changing environmental conditions due to its small body mass, and the increased components of innate immunity in circulation blood may contribute to the enhancement of PHA swelling response.     

Toxic and excitatory effects of the molluscicide metaldehyde on the biofouling bivalve Dreissena polymorpha Pallas

The zebra mussel, Dreissena polymorpha Pallas, is a biofouling freshwater pest for which alternative control methods to the use of chlorine are sought. Metaldehyde, a molluscicide used primarily for control of terrestrial slugs, has also been shown to have efficacy and specificity in the control of aquatic snails. To test its potential for zebra mussel control, we investigated its effects on zebra mussel viability and on contractility of siphon/mantle muscle preparations in vitro. Metaldehyde caused zebra mussel mortality within 48 h at concentrations of approximately 0.1 and 0.2 g litre⁻¹. The same concentrations of metaldehyde activated a complex, excitatory response in previously quiescent siphon/mantle preparations but did not modify the contractile responses of the preparations to acetylcholine. The relatively low level of toxicity of metaldehyde to zebra mussels, compared to its toxicity to snails and slugs, and the difficulty of applying this relatively insoluble molluscicide in the aqueous environment suggest that metaldehyde would not be an effective zebra mussel control agent. © 2000 Society of Chemical Industry     

帽儿山异色瓢虫野外越冬前体内甘油·脂肪含量的变化

[目的]明确野外越冬异色瓢虫[Harmonia axyridis(Pallas)]成虫体内甘油、脂肪2种物质越冬前的动态变化.[方法]利用动力学方法和重量法,分别测定了其体内甘油和脂肪含量.[结果]昼长及温、湿度共同影响异色瓢虫越冬前体内甘油和脂肪含量的变化;在异色瓢虫越冬前,虫体脂肪含量达到最低值,于部分异色瓢虫越冬期间达到最高值;而虫体甘油含量在异色瓢虫越冬前期及部分异色瓢虫越冬期间达到最高值,在几乎全部异色瓢虫越冬期间降到最低值;甘油、脂肪含量变化与昼长及温、湿度变化呈一定相关性,但不显著.[结论]异色瓢虫体内甘油与脂肪含量在越冬前呈互补变化,在部分及全部异色瓢虫越冬期间均呈现上升和下降相似变化,其相应生化指标可作为异色瓢虫越冬的指示.     

异色瓢虫对烟蚜的捕食功能反应及密度干扰效应

异色瓢虫各龄幼虫及成虫对烟蚜的日捕食量差异较大,在相同的烟蚜密度条件下,异色瓢虫Ⅳ龄幼虫的捕食量最大,其次为成虫和Ⅲ龄幼虫。异色瓢虫各龄幼虫及成虫的功能反应均属HollingⅡ型。异色瓢虫自身密度对其捕食作用的干扰效应明显,对烟蚜的日捕食量异色瓢虫密度的增加而减少。     

鸭绿江细鳞鱼Brachymystax lenok(Pallas)的研究

本文对鸭绿江细鳞鱼的形态特征、生殖与洄游和食性进行了论述,并讨论了细鳞鱼引种保护和驯养增殖问题。     

异色瓢虫释放技术概况

概述了国内外释放异色瓢虫(Harmonia axyridis Pallas)防治虫害所采用的技术和方法,包括虫情监测、释放虫量、虫态的选择以及后期管理,旨在为更好地保护和利用这一优势天敌提供参考依据.     

温度对细鳞鲑幼鱼最大代谢率和代谢范围的影响

为了探究温度对细鳞鲑(Brachymystax lenok)幼鱼的代谢特征和有氧运动能力的影响,在不同温度(4℃、8℃、12℃、16℃、20℃)下测定了实验鱼的静止代谢率(RMR)、有氧运动过程中的最大代谢率(MMR)以及能量代谢范围(MS)和临界游泳速度(UCrit)。结果表明,随着温度的上升,RMR和MMR均显著提高(P0.05),各温度下的RMR和MMR分别较4℃条件的提高了62%(8℃)、165%(12℃)、390%(16℃)、411%(20℃)和3%(8℃)、34%(12℃)、111%(16℃)、115%(20℃);MS随水温的升高呈现下降的趋势,且4℃条件具有最大的代谢范围。不同温度条件下UCrit存在显著性差异,但随着温度升高未表现出明显的变化规律。有氧运动过程中,不同流速下测定的MMR多出现在70%UCrit附近,可能是由于无氧代谢过早启动,使得机体乳酸积累过多进,降低了有氧代谢水平。