短时低温对茶黄蓟马发育与繁殖的影响

蓟马是芒果的重要害虫,为探明短时低温对蓟马发育与繁殖的影响,以为害芒果的蓟马优势种茶黄蓟马Scirtothrips dorsalis为对象,将其放置于8℃和12℃(RH 75%±10%, 12 L∶12 D)人工气候箱内,分别处理6 h、12 h及24 h,观察若虫的存活率、发育历期及成虫寿命和繁殖力。结果表明：短时低温暴露对茶黄蓟马若虫的发育历期有一定的影响,不同龄期对低温的响应有所不同,若虫期经历短时低温会显著降低成虫寿命;短时低温暴露对所处理龄期及世代的存活能力均造成显著影响,处理温度越低时间越长,存活率下降越显著,其中2龄若虫在8℃下处理24 h,若虫期的累计存活率最低,仅6.86%。结果说明短时低温暴露后对成虫寿命和产卵量均产生不利的影响,处理温度越低时间越长,影响越大。     

西花蓟马和花蓟马在温度逆境下的存活率比较

以外来入侵害虫西花蓟马(Frankliniella occidentalis)和本地种花蓟马(F.intonsa)为对象,研究了高温和低温逆境下两种蓟马各虫态存活率的差异.结果表明:在36℃～44℃高温下暴露2h和4h,不论是西花蓟马还是花蓟马,各虫态的存活率均随温度的升高而降低,但在相同高温处理条件下,同一虫态西花蓟马的存活率要高于花蓟马;在-2℃～-10℃低温下暴露2h和4h,西花蓟马和花蓟马各虫态的存活率均随随温度的降低而下降;在相同低温处理条件下,同一虫态西花蓟马的存活率也要高于花蓟马.由此表明,2种蓟马对高温和低温的适应能力不同,本地种花蓟马对高温和低温均比较敏感,而外来入侵害虫西花蓟马对极端温度具有较强的适应性.     

异色瓢虫成虫冷驯化反应及体内几种酶活力的相关变化

为明确冷驯化反应对异色瓢虫Harmonia axyridis (Pallas) 实验种群成虫耐寒性及其生殖能力的影响, 本研究测定了成虫低温存活率、过冷却点(supercooling point, SCP)、体内含水量及雌虫繁殖能力等。结果表明: 冷驯化（在5℃下诱导3 d, 5 d）后, 成虫再在-5℃下暴露3 d的存活率由对照（预先未进行冷驯化）的46%分别提高至60%和67%, 而诱导10 d后的存活率(51%)反而下降。冷驯化效应在其成虫转移至饲养条件下7 d后就消失。随着低温诱导时间的延长过冷却点及体内含水量均呈现下降趋势, 短时间(5, 10 d)的诱导不能使成虫的SCP明显降低, 但可以使含水量极显著下降。冷驯化后异色瓢虫雌虫产卵前期延长; 虽然冷驯化对雌虫首次产卵量没有影响, 但是随着诱导时间的延长连续观察72 h内单头雌虫累计产卵量却降低。冷驯化过程中成虫体内几种酶活力的检测结果表明: 两种细胞保护酶超氧化物歧化酶(SOD)与过氧化氢酶(CAT)活性升高, 与新陈代谢有关的乳酸脱氢酶(LDH)及Na⁺, K⁺-ATP酶活性却降低。结果显示, 低温胁迫前异色瓢虫成虫经过不同时间的诱导后有可能提高其低温抵抗能力, 而且冷驯化诱导成虫耐寒性增加是一种复杂的生理生化过程, 这一过程对其生存和繁殖具有重要的适应意义。     

高温和啶虫脒处理西花蓟马对其F1 代生命表参数的联合作用

【目的】西花蓟马 Frankliniella occidentalis (Pergande) (缨翅目: 蓟马科）是一种危险的入侵害虫,其生长发育受温度影响显著。我们的前期研究表明,高温热激对西花蓟马的杀灭效果并不理想,但高温热激可以改变西花蓟马的药剂敏感性。为了探究高温热激后再进行杀虫剂减量处理能否提高高温对西花蓟马的防治效果,本实验测定了45℃高温热激 2 h后恢复不同时间（8 h 和24 h）啶虫脒对西花蓟马F₁代生命表参数的影响,从控制种群发展的角度探究高温和啶虫脒防治西花蓟马最佳结合方式。【方法】应用特定年龄 龄期及两性生命表的方法,研究45℃高温热激和啶虫脒处理西花蓟马后其F₁代种群的生命表参数。【结果】45℃热激2 h后恢复不同时间用啶虫脒处理西花蓟马亲代,其F₁代卵、1龄幼虫和蛹的平均发育历期均显著长于对照（仅45℃热激2 h）的西花蓟马F₁代（P<0.01）;而且其F₁代雌成虫的寿命和产卵量均显著少于对照（P<0.01）。热激恢复8 h后啶虫脒处理西花蓟马亲代,其F₁代发育历期和雌成虫的寿命虽然与热激恢复24 h的F₁代不存在显著性差异,但是其F₁代的平均产卵前期（adult pre-oviposition period, APOP）和平均总产卵前期（total pre-oviposition period, TPOP）显著长于恢复24 h的F₁代（P<0.01）,单雌平均产卵量显著小于恢复24 h的F₁代（P<0.01）。【结论】相比单一高温防治,高温和杀虫剂综合使用对西花蓟马有更好的防控效果。相比热激后恢复24 h,热激后恢复8 h再进行杀虫剂处理对西花蓟马有更好的防控效果。     

乙基多杀菌素和印楝素对西花蓟马生长发育及繁殖的亚致死效应

为探讨乙基多杀菌素和印楝素对西花蓟马的亚致死效应,采用浸叶法确定了它们对西花蓟马2龄若虫的亚致死浓度(LC₂₅),并研究了该浓度下两种生物源农药对西花蓟马生长发育和繁殖力的影响.结果表明: 两种生物源农药亚致死浓度处理对西花蓟马均有不同程度的影响.在两性生殖方式下,乙基多杀菌素对西花蓟马产卵前期、雌成虫寿命和产卵量均无显著影响,但雄成虫寿命显著缩短;印楝素处理后,西花蓟马产卵量显著降低,产卵前期明显延长.在孤雌生殖方式下,不论乙基多杀菌素和印楝素处理,西花蓟马产卵前期均明显延长,但只有印楝素使雌成虫寿命缩短和产卵量显著降低.两种生物源农药对西花蓟马次代各虫态的发育历期影响不同,无论在何种生殖方式下,乙基多杀菌素处理后西花蓟马的未成熟期均明显短于印楝素处理.乙基多杀菌素处理后西花蓟马的内禀增长率(r_m)和周限增长率(λ)均高于对照,而印楝素较对照低.以上结果说明,两种杀虫剂对西花蓟马生长发育和繁殖影响不同,乙基多杀菌素亚致死浓度对西花蓟马种群的增长有一定的刺激作用,而印楝素有明显的抑制作用.两种杀虫剂的影响程度还与西花蓟马的生殖方式有关.     

西花蓟马与烟蓟马生物学特性的比较研究

本试验研究并比较了外来入侵物种西花蓟马Frankliniella occidentalis(Pergande)与本地物种烟蓟马Thrips tabaci Lindeman的生物学特性,包括种群增长速度、发育历期、成虫寿命、孤雌生殖方式下的产卵量以及产卵规律等几个方面。结果显示,当以相同的数量在紫甘蓝上饲养时,只经过3代,烟蓟马的种群数量就可以达到西花蓟马的3倍,随后对2种蓟马种群的性别比进行了鉴定后发现,西花蓟马种群的雌雄比为2.8∶1,而烟蓟马种群中的所有个体均为雌性。除了2龄若虫期和预蛹期之外,烟蓟马在紫甘蓝上的发育历期明显长于西花蓟马,而其雌虫的平均寿命显著短于西花蓟马雌虫,分别是24.94d和43.35d。进行孤雌生殖时,西花蓟马的终生产卵量明显多于烟蓟马,但是在日均产卵量方面,这一情况却相反。     

温度对西花蓟马生长发育、 繁殖和种群增长的影响

西花蓟马Frankliniella occidentalis (Pergande)是一种入侵我国的重要害虫, 温度是决定蓟马能否建立稳定种群的最基本因素。为明确温度对西花蓟马种群增长的影响, 本研究在室内观察了西花蓟马在15℃, 20℃, 25℃, 30℃和35℃温度条件下的生长发育、 存活与繁殖能力, 并计算各温度条件下的种群增长参数。结果表明： 在35℃条件下, 西花蓟马不能完成发育, 其他温度条件下西花蓟马从卵孵化至蛹羽化成成虫, 以20℃条件下的存活率最高, 为62.8%。西花蓟马发育速率随温度升高明显加快, 在15℃下, 完成发育需要近30 d; 而在30℃下, 西花蓟马完成发育仅需10 d 左右。西花蓟马成虫寿命随温度的升高而明显缩短, 在15℃下, 平均寿命为36 d, 最长寿命达60 d; 在30℃下, 西花蓟马的平均寿命为10 d。西花蓟马在 15℃, 20℃和25℃条件下的平均繁殖力差异不显著, 分别为37.70, 32.56, 37.80头1龄若虫/雌, 但显著高于30℃条件下的平均繁殖力（9.36头1龄若虫/雌）。西花蓟马的种群增长参数净生殖率(R0)、 内禀增长率(rm), 在25℃时达最高值, 分别为20.10和0.178 d-1, 而在15℃下分别仅为18.67和0.096 d-1。据此得出, 20~25℃是最适宜西花蓟马生长发育和繁殖温度范围, 温度过高或过低都不利于西花蓟马种群增长。西花蓟马的发育起点温度为7.4℃, 充分完成发育所需的有效积温为208.0日·度。不考虑其他阻碍生长发育因素的情况下, 华南、 华中、 华北和东北地区的年发生代数分别为24~26, 16~18, 13~14和1~4代, 西南地区昆明与丽江分别为13~15和8~10代。     

温度对西花蓟马(Frankliniella occidentalis)生长发育和存活率的影响

在15、20、25℃和30℃,RH75％的条件下,分析了温度与西花蓟马发育速率的关系,并测定了西花蓟马的发育起点温度、有效积温和存活率。结果表明：在15～30℃范围内,西花蓟马各虫期的发育速率随温度的升高而加快;用直接最优法对发育起点温度和有效积温进行估算,求得西花蓟马的卵、若虫、预蛹和伪蛹及世代发育起点温度分别为5．70、7．04、4．49、6．84℃和6．23℃;世代的有效积温为219．73d&#183;℃。西花蓟马的世代存活率在25℃时最高,为40．12％;30℃时西花蓟马的存活率最低,为17．80％。     

在CO_2浓度升高条件下西花蓟马和花蓟马的生长发育及繁殖力比较

为明确大气CO2浓度升高对外来入侵害虫西花蓟马Frankliniella occidentalis及其本地近缘种花蓟马F.intonsa的影响,利用两种CO2浓度(800μL/L vs.400!L/L)的人工气候箱研究了西花蓟马和花蓟马未成熟期的发育历期、累积存活率、单雌产卵量及净生殖率等种群参数。结果表明:在CO2浓度倍增条件下(800μL/L),西花蓟马和花蓟马的非成虫历期显著短于对照CO2浓度(400μL/L)下的种群;花蓟马的累积存活率比对照下降了26.30%(P0.05),而西花蓟马的累积存活率与对照差异不显著;西花蓟马的单雌平均产卵量比对照组增加了4.17粒,而花蓟马的雌成虫寿命、成虫平均单雌产卵量和日均单雌产卵量分别降低了1.31 d、4.83粒和0.56粒(P0.05)。与对照相比,高CO2浓度处理下西花蓟马种群的净生殖率(R0)、内禀增长率(rm)和周限增长率(λ)均显著增加,而平均世代周期(T)、种群加倍时间(t)均明显减少;而花蓟马则相反,其种群的R0、rm和λ均显著降低,T和t均明显长于对照(P0.05)。在相同CO2浓度下,西花蓟马的非成虫虫态历期短于花蓟马;两种蓟马非成虫虫态的不同发育阶段存活率由高至低的顺序相同,依次为:蛹期预蛹期2龄若虫期1龄若虫期。研究结果说明入侵种西花蓟马对未来高CO2浓度大气环境的适应性强于本地种花蓟马。     

短时高温暴露对Q型烟粉虱存活和生殖适应性的影响

在室内将Q型烟粉虱Bemisia tabaci Q-biotype成虫在44℃下暴露1 h后观察成虫的存活率、产卵量、雌雄寿命和后代存活能力,以研究短时高温暴露对Q型烟粉虱生物学特性的影响。结果表明,Q型烟粉虱成虫在44℃下暴露1 h后的存活率为43.5%,暴露热激后的单头雌虫的产卵量为77.2粒,低于常温下(26℃)的产卵量(100.1粒);短时高温可显著缩短Q型烟粉虱成虫的寿命,在44℃下暴露1 h后Q型烟粉虱雌雄虫寿命分别为14.5 d和10.2 d,显著低于常温下(26℃)雌虫20.4 d和雄虫18.2 d;短时高温对Q型烟粉虱后代存活率和雌雄性比无显著影响,但其产卵高峰期延迟,产卵持续期缩短。以上结果表明,短时高温热激可影响Q型烟粉虱的生殖情况,造成Q型烟粉虱产卵量降低和寿命缩短,Q型烟粉虱雌虫耐热性强于雄虫。     

Expression of a beetle, Dendroides canadensis, antifreeze protein in Drosophila melanogaster

Antifreeze protein 1 (DAFP-1), from the beetle Dendroides canadensis, was expressed in Drosophila melanogaster. Mean thermal hysteresis values (the difference between freezing and melting points), indicative of antifreeze protein activity, in the hemolymph of transgenic flies were found to be as high as 6.23+/-0.10 degrees C (using the nanoliter osmometer). Direct comparisons of the capillary and nanoliter osmometer techniques for measuring THA were made, illustrating the much higher values obtained by the latter. Transgenic Drosophila had supercooling points, both in contact with ice and not, that were slightly, but significantly, lower than wild-type controls (1.5-2.0 degrees C and 2.0-4.0 degrees C, respectively). The results indicate functionality of DAFP-1 in Drosophila melanogaster (the ability of DAFP-1 to inhibit both inoculative freezing across the cuticle and freezing initiated by endogenous ice nucleators). The much larger effects of DAFPs in inhibiting inoculative freezing and ice nucleation in Dendroides canadensis relative to the transgenic Drosophila may partially result from the lower DAFP concentrations and activities in Drosophila, however the absence of multiple types of DAFPs and absence of tissue specific expression may also contribute. Transgenic Drosophila were also able to live significantly longer than controls at 0 degrees C and 4 degrees C, indicating that DAFP-1 is able to increase cold tolerance at above freezing temperatures.     

Complete genome sequence of Granulicella mallensis type strain MP5ACTX8T,an acidobacterium from tundra soil

Granulicella mallensis MP5ACTX8^T is a novel species of the genus Granulicella in subdivision 1of Acidobacteria. G. mallensis is of ecological interest being a member of the dominant soil bacterial community active at low temperatures and nutrient limiting conditions in Arctic alpine tundra. G. mallensis is a cold-adapted acidophile and a versatile heterotroph that hydrolyzes a suite of sugars and complex polysaccharides. Genome analysis revealed metabolic versatility with genes involved in metabolism and transport of carbohydrates. These include gene modules encoding the carbohydrate-active enzyme (CAZyme) family involved in breakdown, utilization and biosynthesis of diverse structural and storage polysaccharides including plant based carbon polymers. The genome of Granulicella mallensis MP5ACTX8^T consists of a single replicon of 6,237,577 base pairs (bp) with 4,907 protein-coding genes and 53 RNA genes.     

Complete genome sequence of Granulicella tundricola type strain MP5ACTX9T,an Acidobacteria from tundra soil

Granulicella tundricola strain MP5ACTX9^T is a novel species of the genus Granulicella in subdivision 1 Acidobacteria. G. tundricola is a predominant member of soil bacterial communities, active at low temperatures and nutrient limiting conditions in Arctic alpine tundra. The organism is a cold-adapted acidophile and a versatile heterotroph that hydrolyzes a suite of sugars and complex polysaccharides. Genome analysis revealed metabolic versatility with genes involved in metabolism and transport of carbohydrates, including gene modules encoding for the carbohydrate-active enzyme (CAZy) families for the breakdown, utilization and biosynthesis of diverse structural and storage polysaccharides such as plant based carbon polymers. The genome of G. tundricola strain MP5ACTX9^T consists of 4,309,151 bp of a circular chromosome and five mega plasmids with a total genome content of 5,503,984 bp. The genome comprises 4,705 protein-coding genes and 52 RNA genes.     

Cold Hardening of Meloidogyne hapla Second-stage Juveniles

The effect of previous exposure to low temperatures on freezing tolerance was determined for second-stage juveniles of Meloidogyne hapla. Juveniles in 5% polyethylene glycol 20,000 were exposed to 0-24 C for 12-96 hours, and then freezing tolerance was assessed by freezing samples at -4 C for 24 hours, thawing, and determining survival. Freezing tolerance was inversely related to prefreeze temperatures of 4-24 C. Prefreeze exposure to 4 C resulted in fourfold greater freezing tolerance than did exposure to 24 C. Mortality occurred during prefreeze exposure to 0 C. Most of the increase in freezing tolerance at 4 C occurred during the first 12 hours. In soil, prefreeze exposure to 4 C resulted in greater freezing tolerance than did prefreeze exposure to 24 C.     

Antioxidant responses of citrus red mite, Panonychus citri (McGregor) (Acari: Tetranychidae), exposed to thermal stress

Relatively low or high temperatures are responsible for a variety of physiological stress responses in insects and mites. Induced thermal stress was recently associated with increased reactive oxygen species (ROS) generation, which caused oxidative damage. In this study, we examined the time-related effect of the relatively low (0, 5, 10, and 15 °C) or high (32, 35, 38, and 41 °C) temperatures on the activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), peroxidases (POX), and glutathione-S-transferase (GST), and the total antioxidant capacity (TEAC) of the citrus red mite, Panonychus citri (McGregor). The malondialdehyde (MDA) concentration, as a marker of lipid peroxidation in organisms, was also measured in the citrus red mite under thermal stress conditions. Results showed that SOD and GST activities were significantly increased and play an important role in the process of antioxidant response to thermal stress. Lipid peroxidation levels increased significantly (P < 0.001) and changed in a time-dependent manner. CAT and POX activity, as well as TEAC, did not vary significantly and play a minor role to remove the ROS generation. These results suggest that thermal stress leads to oxidative stress and antioxidant enzymes play an important role in reducing oxidative damage in the citrus red mite.     

绿盲蝽越冬卵的耐寒能力

近年来,随着转基因棉花的大面积推广,绿盲蝽成为了我国棉花和果树生产的重要害虫。为了阐明绿盲蝽越冬生态适应性,研究了绿盲蝽卵在越冬过程中的耐寒力变化,测定了卵内生化物质的含量,结果表明:绿盲蝽越冬卵低温存活力呈现出明显的月份变化,在-10℃、-20℃处理下,绿盲蝽的越冬卵的半致死时间从大到小的顺序依次为:1月>2月>12月>3月>4月,在-30℃处理下从大到小的顺序依次为:1月>12月>3月>2月>4月。在极端低温(-20℃)下1、2、3、4和5 d后,4月份保护卵死亡率明显低于相同处理下的4月份裸露卵的死亡率,枣枝中的越冬卵死亡率分别为4.32%、5.36%、5.42%、6.79%和7.63%,剥离出来的越冬卵死亡率分别为46.06%、51.84%、54.59%、63.07%和74.41%。人工滞育卵的耐寒性强于正常发育卵的耐寒性,弱于自然越冬过程中滞育卵的耐寒性。冷驯化可以显著提高绿盲蝽越冬卵的低温存活力,在0℃冷驯化20 min后,越冬卵的低温(-20℃、100 h)死亡率显著降低,冷驯化40 min后,低温死亡率趋于平稳,均在37%左右。越冬卵体内物质呈明显的季节性变化,越冬卵越冬期的含水量显著高于越冬后,其中1月份最高(43.98%),4月份达到最低(38.79%)。越冬卵体内总脂肪含量在整个越冬过程中逐渐降低,从12月份的38.24%,降低到4月份的27.08%。蛋白质和糖的含量均是先降低后升高,其中蛋白质从12月份的78.77μg/mg,降低到1月份的59.80μg/mg,然后又逐渐升高至4月份的73.62μg/mg,体内总糖含量由12月份的39.60μg/mg降低至1月份的21.17μg/mg,然后又逐渐升高至4月份的35.10μg/mg。绿盲蝽越冬卵的耐寒力随着月份的变化而变化,在整个越冬期间表现出较强的抗寒性,能够抵御冬季低温,而其越冬场所的保护作用增加了其对于冬季严寒的适应性。     

Middle Pleistocene fossil Cercopithecidae from Asbole, Afar Region, Ethiopia

A sample of 117 fossil cercopithecids has been collected from the Middle Pleistocene site of Asbole, Afar Region, Ethiopia. A minimum of five species is present. There are two species of Cercopithecini, here recognized as cf. Chlorocebus aff. aethiops, and cf. Chlorocebus cf. patas. There are also two species of Papionini: Papio hamadryas ssp. indet. and Theropithecus oswaldi leakeyi. Finally, there is a single species of colobine present, Colobus sp. indet. The assemblage is chronologically constrained and is derived from sediments dated to approximately 600 ka. Within this sample Colobus sp. is by far the most common species present, outnumbering the other four species combined. The cercopithecid assemblage is most consistent with a woodland habitat, corroborating an earlier interpretation based on the non-primate fauna. Taxonomic, biogeographic, and evolutionary implications of the assemblage are also discussed.     

Unification of the genera Nonlabens, Persicivirga, Sandarakinotalea and Stenothermobacter into a single emended genus, Nonlabens, and description of Nonlabens agnitus sp. nov

Phylogenetic analyses based on 16S rRNA gene sequences showed that a bacterial isolate, designated JC2678(T), represents a distinct phyletic line within the suprageneric monophyletic clade containing the genera Nonlabens, Persicivirga, Stenothermobacter and Sandarakinotalea. The polyphasic data presented in this study demonstrated that the members belonging to the Nonlabens-like clade overall constitute a single genus. Therefore, it is proposed to transfer the members of genera Persicivirga O'Sullivan et al. 2006, Stenothermobacter Lau et al. 2006 and Sandarakinotalea Khan et al. 2006 to the genus Nonlabens Lau et al. 2005. Thus, P. dokdonensis (Yoon et al. 2006) Nedashkovskaya et al. 2009, P. ulvanivorans Barbeyron et al. 2010, P. xylanidelens O'Sullivan et al. 2006, Sandarakinotalea sediminis Khan et al. 2006 and Stenothermobacter spongiae Lau et al. 2006 should be transferred to Nonlabens dokdonensis comb. nov., Nonlabens ulvanivorans comb. nov., Nonlabens xylanidelens comb. nov., Nonlabens sediminis comb. nov. and Nonlabens spongiae comb. nov., respectively. In addition, strain JC2678(T) (=KACC 14155(T)=JCM 17109(T)) is proposed to constitute a novel species belonging to the genus Nonlabens with the name of Nonlabens agnitus sp. nov.     

Systematics of Australian Thrasorinae (Hymenoptera, Cynipoidea, Figitidae) with descriptions of Mikeiinae, new subfamily, two new genera, and three new species

The Australian Thrasorinae are revised and Mikeius is transferred to Mikeiinae Paretas-Martínez & Pujade-Villar, subfam. n., and Mikeius clavatus Pujade-Villar & Restrepo-Ortiz, sp. n., is described. Two new genera of Thrasorinae are erected: Cicatrix Paretas-Martínez, gen. n., including Cicatrix pilosiscutum(Girault), comb. n. from Amblynotus, Cicatrix schauffi (Buffington), comb. n. from Mikeius, and Cicatrix neumannoides Paretas-Martínez & Restrepo-Ortiz, sp. n.; and Palmiriella Pujade-Villar & Paretas-Martínez, gen. n., including Palmiriella neumanni (Buffington), comb. n. from Mikeius, Thrasorus rieki Paretas-Martínez & Pujade-Villar, sp. n., is also described. A phylogenetic analysis of 176 morphological and biological characters, including all these new taxa and all genera previously included in Thrasorinae, was conducted. All subfamilies were recovered as monophyletic, with the following relationships: Parnipinae (Euceroptrinae (Mikeiinae (Plectocynipinae (Thrasorinae)))). A worldwide key to the subfamilies of Figitidae is provided that includes the new subfamily, as well as a key to genera Thrasorinae.