美丽青背姬小蜂寄生和繁殖特性研究

美丽青背姬小蜂Chrysonotomyia formosa(Westwood)是美洲斑潜蝇的优势天敌,在美洲斑潜蝇的自然控制中发挥着非常重要的作用.本文对其寄生和繁殖特性进行了研究,结果表明:美丽青背姬小蜂主要将卵产于寄主幼虫的腹部,1头寄主幼虫体内可产1～5粒卵,但只有1粒卵能完成发育成为成蜂;不同温度下,雌蜂的繁殖能力不同,其中雌蜂在23℃时有最大的产卵量和最高的致死寄主个体数;提供10%的蜂蜜水可以显著提高雌蜂对寄主的寄生数、产卵量、刺死寄主数和总致死寄主数;美丽青背姬小蜂也能进行产雄孤雌生殖;营孤雌生殖的雌蜂与有性生殖的雌蜂在寿命、寄生寄主数、产卵数、刺死寄主数和总致死寄主数之间差异不显著.     

有机磷类杀虫剂对美洲斑潜蝇的防治效果

在山东青州以西葫芦为试验害虫寄主 ,测定了毒死蜱、三唑磷、乙酰甲胺磷、辛硫磷、马拉硫磷对美洲斑潜蝇幼虫LiriomyzasativaeBlanchard的田间防效。毒死蜱 (2 4g (a .i.) 667m2 )、三唑磷 (1 0g (a.i.) 667m2 )、乙酰甲胺磷 (2 0g (a .i.) 667m2 )第 3～ 7d校正防效为 97 0 9%～ 97 1 4% ,86 80 %～87 0 4% ,85 99%～ 86 2 5 %。此 6个处理药效顺序为毒死蜱 >三唑磷 >乙酰甲胺磷 (2 0g(a.i.) 667m2 )>乙酰甲胺磷 (1 5g(a.i.) 667m2 ) >辛硫磷 >马拉硫磷。在河南洛阳以甘蓝为试验害虫寄主 ,乙酰甲胺磷 (1 5g(a.i.) 667m2 )、敌敌畏 (2 5g(a.i.) 667m2 )、敌百虫 (4 5g(a .i.) 667m2 )对美洲斑潜蝇幼虫第 7d校正防效分别为 76 98% ,82 42 % ,71 1 1 %。毒死蜱对在不同寄主上美洲斑潜蝇的防效均较好     

山东省泰安地区美洲斑潜蝇及其寄生蜂消长规律的研究

近3年以来,笔者对山东省美洲斑潜蝇及其寄生蜂种群的季节性消长规律进行了研究.结果表明,美洲斑潜蝇在泰安灌庄菜区露地栽培蔬菜上于7月中旬、8月中旬至9月中旬出现两个发生高峰,寄生蜂的种群高峰则在7月下旬和9月末.春末夏初以异角姬小蜂Hemiptarsenus varicornis(Girault)为主,随着时间推移,逐渐以丽潜蝇姬小蜂Neochrysocharis formosa Westwood和绿凹面姬小蜂Chrysochauis pentheus(Ualker)为主.在寄生蜂发生盛期,应注意保护利用.     

美洲斑潜蝇外寄生蜂——贝氏潜蝇姬小蜂研究进展

贝氏潜蝇姬小蜂是为害多种农作物的几种潜叶蝇类害虫的重要寄生蜂.作为一种重要生物防治因子,在北美和西欧的一些国家和地区已经进行商品化生产,用来防治蔬菜及观赏性花卉上的美洲斑潜蝇和三叶草斑潜蝇.为了对其有一个较全面的了解,本文详细的论述了贝氏潜蝇姬小蜂的寄主范围,生物学,饲养繁殖及化学杀虫剂对其影响的进展.     

植物乙醇提取物对美洲斑潜蝇寄生性天敌的影响

本文研究了马缨丹Lantana camara、飞机草Chromolaena odorata和蟛蜞菊Wedeliachinensis乙醇提取物以及机油乳剂对美洲斑潜蝇两种主要寄生蜂底比斯釉姬小蜂Chrysochairis pentheus((Walker)和丽潜蝇姬小蜂Neuchrysocharis formosa(Westwood)的影响,研究结果表明:供试的三种植物乙醇提取物对美洲斑潜蝇上述两种寄生蜂的成、幼蜂无毒杀作用,对底比斯釉姬小蜂和丽潜蝇姬小蜂的寄生行为均无影响.     

美洲龟甲轮虫的分类特征及与我国热带地区常见龟甲轮虫的比较

美洲龟甲轮虫Keratella americana Carlin,1943年被认为主要分布在美洲地区,但陆续报告在其他地区有出现。2015年在对华南地区浮游动物调查时发现,星云湖、抚仙湖、百色水库及飞来峡水库中均出现该种类。检测了广西百色水库中龟甲轮虫的COⅠ序列,与已知美洲龟甲轮虫序列相似度高达98%。中国该龟甲轮虫种群与墨西哥美洲龟甲轮虫种群间差异度为2%,进一步确定为美洲龟甲轮虫。文章描述了美洲龟甲轮虫形态及生境,使用扫描电镜法比较了美洲龟甲轮虫、螺形龟甲轮虫Keratella cochlearis（Gosse,1851）、热带龟甲轮虫Keratella tropica（Apstein,1907）及无棘龟甲轮虫Keratella tecta（Gosse,1851）的咀嚼器。美洲龟甲轮虫主要特点为:背甲长度远大于宽度,侧中棘刺短于侧棘刺,背甲中央最后一个板块未封闭,向后棘刺延伸。4种龟甲轮虫咀嚼器主要区别在于砧基的形状,美洲龟甲轮虫砧基比其他3种轮虫发达,螺形龟甲轮虫砧基似“T”形,热带龟甲轮虫砧基为扇形,无棘龟甲轮虫平直。种间的砧基存在明显差异,可作为热带地区龟甲轮属的分类依据。     

Effects of inoculation with arbuscular mycorrhizal fungi on photosynthetic physiology in females and males of Populus deltoides exposed to cadmium pollution

Aims Populus deltoides is an important plantation tree species in the middle and lower reaches of the Yangtze River and in Huai River Plain. The extensively cultivated varieties are consisted of both females and males of P. deltoides. The objective of this paper was to characterize the difference in cadmium (Cd) tolerance between the sexes and the effects of symbiosis with Rhizophagus intraradices on their Cd tolerance.
Methods The experiment was carried out under semi-controlled conditions in a natural light greenhouse, protected from rain. Rhizophagus intraradices was inoculated on roots of both females and males when transplanting to a sand culture substrate. After one month, half of cuttings were exposed to Cd pollution (10 mg·kg^-1). All cuttings were irrigated with sterile water to avoid infection by other microorganism. About three months later, the gas exchange rate, net photosynthesis rate (P_n)-intercellular CO₂ concentration (C_i) curve, chlorophyll fluorescence, osmotic adjustment and phytohormone content of both females and males of P. deltoides were measured.
Important findings Our main results are as follows: (1) when compared to the controls, decreases in P_n, stomatal conductance, C_i, transpiration rate, maximum photochemical efficiency of photosystem II (PSII), effective quantum yield of PSII, photo-chemical quenching coefficient, maximum rate of carboxylation of Rubisco, photosynthetically active radiation-saturated rate of electron transport and rate of triose phosphate utilization to a different degree in both sexes of P. deltoides under Cd pollution were found, and females exhibited a greater decrease in such parameters than males. Rhizophagus intraradices inoculation mitigated the toxic effect of Cd on such parameters to a different degree in females, not in males. (2) Under Cd pollution, there was an increase in proline content in both sexes when compared to the controls. A further increase in proline content occurred in females, not in males, when inoculated with R. intraradices. (3) When compared to the controls, there was a decrease in indoleacetic acid, but an increase in abscisic acid in leaves of both sexes when exposed to Cd pollution. The amplitude changed in both phytohormones in females was greater than that in males. Rhizophagus intraradices inoculation was helpful for recovery of phytohormone balance in females, which was not observed in males. Therefore, our results indicated that (1) there were a greater negative effect exerted by Cd pollution on gas exchange rate, carbon fixation capacity and phytohormone balance and a more impairment of photosynthetic apparatus in females when compared to males, showing a less tolerance to stress conditions in females; (2) Rhizophagus intraradices inoculation could enhance the osmotic adjustment capacity in females, thus mitigate the negative effect of Cd stress on ability of carbon fixation and phytohormone balance in females. However, such positive effects derived from R. intraradices symbiosis were not observed in males.     

四种鬼臼毒素类似物对美洲大蠊腹神经索动作电位的作用

为了解鬼臼毒素对昆虫神经系统的影响,采用胞外记录电生理方法观察了4种鬼臼毒素类似物对美洲大蠊Periplaneta americana 中枢神经自发放动作电位的影响。结果显示: 在0.1 mmol/L的浓度下,4种物质对美洲大蠊中枢神经自发放动作电位的作用不同。脱氧鬼臼毒素可完全抑制美洲大蠊中枢神经自发放动作电位的产生,其抑制作用可逆;β-阿朴苦鬼臼毒素对美洲大蠊中枢神经自发放动作电位的作用是先兴奋后抑制;鬼臼毒素对美洲大蠊中枢神经自发放动作电位有抑制作用,其抑制作用不完全;4′-去甲鬼臼毒素对大蠊中枢神经自发放动作电位无影响。结果提示,4种鬼臼毒素类似物对昆虫中枢神经自发放动作电位的影响方式与其结构官能团密切相关。     

中国山杨与美洲山杨杂交育种的研究

通过采用山杨7个种源11株优树与美洲山杨8个优树进行杂交,共进行88个组合,其中46个杂交获得成功,进行播种育苗,建立子代测定林。5年的试验结果表明,山杨作母本时,以苇河种源较好;美洲山杨作父本时T-32-57和T-28-56较好,其它亲本的杂交组合尚需进一步观察。而在部分山杨与美洲山杨杂交种无性系试验林中,Id42-3、Gd42-1、Ca42-1和Bd44-1生长速度快、光合能力较强,抗病虫能力强,是有希望的杂交种。     

霞浦县美洲斑潜蝇发生危害及其防治

美洲斑潜蝇(LiriomyzasativaeBlanchard)是我县新近发现的检疫性害虫,可危害多种蔬菜、花卉及杂草,对农业生产威胁严重,为了控制美洲斑潜蝇的发生危害,我们从1996-1999年对该虫在霞浦县的发生和防治做了调查研究。现将结果报道如下。1　美洲斑潜蝇在我县的发生情况1.1　分布范围广在全县乡(镇)普查中已发现12个乡(镇)均有美洲斑潜蝇不同程度的发生危害,占全县乡(镇)数的85.2%,年发生面积达1601.7hm2,占蔬菜种植面积的51.2%。1.2　危害植物种类多美洲斑潜蝇在我县寄主范围很广,在调查的植物中寄主达11科、43种(品种)作物、8种杂草及花卉,主…