Overwintering colonies of German (Vespula germanica) and common wasps (Vespula vulgaris) (Hymenoptera: Vespidae) in New Zealand

Abstract

Nests of both common (Vespula vulgaris) and German wasps (V. germanica) sometimes overwinter in New Zealand. Three overwintering common wasp colonies were found in low-altitude honeydew beech forest; about 2% of the colonies initiated there in 1988 survived the winter. Wasp traffic rates from nests in Nelson city and a nation wide survey of wasp abundance, showed that more German wasp than common wasp workers were on the wing in winter and spring. German wasp colonies in Nelson city were more likely to overwinter than were common wasp colonies. Of the active German wasp colonies recorded in Nelson in January and February 1989, only two (4%) had previously overwintered, but these two nests accounted for 38% of all German wasp workers estimated to leave nests in the area. Had other overwintering colonies not been poisoned, overwintering colonies might have accounted for up to 11 % of nests and produced up to 64% of German wasp workers on the wing in January and February 1989.

Overwintering common wasp colonies did not produce queens or drones in their first year or second spring, but all 10 overwintering German wasp colonies examined produced sexuals at both times. German wasp queens produced in winter and spring may influence the number of colonies successfully initiated and affect the population dynamics of German wasps in New Zealand.     

Circadian locomotor rhythm masked by the female reproduction cycle in cockroaches

Blattella bisignata (Brunner) and B. germanica (L.) are oviparous cockroaches with cyclic reproductive behaviour, but in B. germanica only males show circadian rhythmicity of locomotion at 28°C and DD (constant darkness). In B. bisignata, males and virgin females cockroaches entrained by light–dark cycles show free‐running rhythmicity in DD, and most activities occur during the subjective night. Daily locomotor activities of virgin females show cyclic changes that coincided with ovarian development. Virgin females also exhibit calling behaviour during the subjective night, and this shows a free‐running rhythm. Male mate‐finding locomotion and female calling behaviour are under circadian control, so the timing for both behaviours is synchronized. However, most mated females do not show a locomotor free‐running rhythm under DD conditions. Our results indicate that only mated females could not express a circadian locomotor rhythm. Pregnancy reduces a female’s locomotory intensity and masks the expression of a circadian locomotor rhythm. We attribute the differences in circadian locomotory rhythms between these two species to their living environments and mate‐finding strategies.     

Waardenburg syndrome type II in a Chinese pedigree caused by frameshift mutation in the SOX10 gene

Waardenburg syndrome (WS) is a congenital hereditary disease, attributed to the most common symptoms of sensorineural deafness and iris hypopigmentation. It is also known as the hearing-pigmentation deficient syndrome. Mutations on SOXl0 gene often lead to congenital deafness and has been shown to play an important role in the pathogenesis of WS. We investigated one family of five members, with four patients exhibiting the classic form of WS2, whose DNA samples were analyzed by the technique of Whole-exome sequencing (WES). From analysis of WES data, we found that both the mother and all three children in the family have a heterozygous mutation on the Sex Determining Region Y - Box 10 (SOX10) gene. The mutation was c.298_300delinsGG in exon 2 of SOX10 ({"type":"entrez-nucleotide","attrs":{"text":"NM_006941","term_id":"1732746331"}}NM_006941), which leads to a frameshift of nine nucleotides, hence the amino acids (p. S100Rfs*9) are altered and the protein translation may be terminated prematurely. Further flow cytometry confirmed significant down-regulation of SOX10 protein, which indicated the SOX10 gene mutation was responsible for the pathogenesis of WS2 patients. In addition, we speculated that some other mutated genes might be related to disease phenotype in this family, which might also participate in promoting the progression of WS2.     

白毛黑眼兔等四种实验兔黑色素分布的组织学观察与比较

目的：分析包括白毛黑眼兔在内的四个品种实验兔的虹膜和皮肤组织中的黑色素分布情况和相互之间的差异。方法通过组织切片和硫酸亚铁染色,对四个品种实验兔的虹膜和皮肤组织中的黑色素含量和分布进行了观察与比较。结果与其背景白化品种相比,白毛黑眼兔不仅在虹膜组织中出现了类型完整的黑色素,而且在其表型为白色的皮肤的毛囊中也出现了低含量的黑色素。结论本结果为白毛黑眼兔突变表型机理研究提供了一定线索。     

The influence of past experience on wasp choice related to foraging behavior

Memory has been little studied in social wasps. Vespula germanica （Fab.） （Hymenoptera： Vespidae） frequently revisits nondepleted food sources, making several trips between the resource and the nest. In this study, we analyzed this relocating behavior in order to evaluate whether this species is capable of remembering an established association after 1 h. To this end, we trained wasps to feed from a certain array. Then it was removed, setting it up again 1 h later, but this time 2 baited feeders were put in place, one at the original feeding site and the other opposite the first. We recorded the proportion of returning foragers, and their choice of feeder, after either 1 or 4 feeding trials. After 1 h, 78% of wasps trained with 4 feeding trials and 65% trained with 1, returned to the experimental area. Furthermore, during the testing phase, wasps trained with 4 feeding trials collected food from the previously learned feeder significantly more frequently than from the nonlearned one （P 〈 0.05）. In contrast, wasps that had been trained only once chose both feeders equally. Thus, memory retrieval could be observed 1 h after wasps had collected food on 4 consecutive occasions, but not after only 1. To our knowledge, this is the first study showing that V. germanica is capable of remembering an association 1 h after the last associative event, demonstrating that 1 h does not impair memory retention if4 feeding experiences have occurred.     

Molecular and morphological variation of rare endemic oncocyclus irises (Iridaceae) of Lebanon

Oncocyclus irises endemic to Lebanon form a complex of three closely related taxa replacing each other over short geographical distances in a linear habitat. In order to characterize the appropriate taxonomic levels and to assess their conservation status, we investigated patterns of phenotypic variability and the partitioning of genetic variation within and among populations using random amplified polymorphic DNA (RAPD) markers. Multivariate analysis (principal components analysis and multiple correspondence analysis), based on 16 quantitative and six qualitative characters, revealed no separation between populations or taxa. Moreover, no morphological character could be used to define clear boundaries between populations/taxa. The genetic characterization revealed high levels of polymorphism and diversity (H_s). Principal components analysis showed population delimitations, but no groupings reflecting the currently defined taxa could be identified. Both morphological and genetic data showed that Lebanese oncocyclus irises could not be fitted into clear taxonomic boundaries. Consequences for conservation are discussed. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 123–135.     

Floral herbivory at different stages of flower development changes reproduction in <Emphasis Type="Italic">Iris gracilipes</Emphasis> (Iridaceae)

Floral herbivores and pollinators are major determinants of plant reproduction. Because interaction of floral herbivores and pollinators occurs when herbivores attack the flowers in the bud and flower stages and because the compensatory ability of plants is known to differ according to the timing of herbivory, the effects of herbivory may differ according to its timing. In this study, we investigated the effects of floral herbivory at different stages on fruit production and seed/ovule ratio at two sites of large populations of the perennial herb, Iris gracilipes for 2 years. Herbivory at the bud and fruit stages both tended to have negative effects on fruit production, but the former caused more severe damage. On the other hand, herbivory at the flower stage tended not to have negative effects on fruit production because the degree of flower loss was smaller in the flower stage. Although herbivory decreased fruit production, flowers did not compensate for the damage by increasing the seed/ovule ratio because reproduction of I. gracilipes was limited by pollen availability rather than resources. These results indicate that floral herbivory at different stages has different effects on plant reproduction.     

光周期与温度对林地德国小蠊生长发育与繁殖的影响

为弄清湖南株洲(北纬27°50′,东经112°54′)栖息于林地的德国小蠊(Blattella germanica)季节生活史策略,研究了光周期和温度对其若虫发育、龄数变异及成虫繁殖的影响。结果表明,德国小蠊的若虫发育明显受光周期的影响。长日条件(LD 16∶8h)下若虫发育最快,中间日长(LD 14∶10h)次之,短日条件(LD 12∶12h)下若虫发育最慢。将孵化后30日的若虫自长日条件向短日条件转移,则若虫发育受到明显抑制,反方向的转移,则若虫发育迅速。说明德国小蠊若虫存在滞育现象,短日条件诱导并维持滞育,长日条件解除滞育。若虫期经历的龄数受光周期和温度的影响,25℃的温度条件下,LD 16∶8h、LD 14∶10h及LD 12∶12h若虫期的龄数分别为7、8和9龄;长日条件下,30℃和25℃的若虫龄数为7龄,而20℃为9龄。根据实验室观察和林地调查结果,德国小蠊在湖南株洲1年发生1代,以滞育若虫越冬。30℃、25℃、20℃的温度条件下,卵鞘成活率分别为14.3%、90.1%和51.9%,高温和低温均不适合德国小蠊的繁殖。因此,可以认为控制若虫发育和龄数的光周期、温度反应的生态意义在于调控繁殖虫态和繁殖的适宜季节保持同步。     

黄菖蒲适生环境筛选

对黄菖蒲（Iris pseudacorus L．）在旱生（CK）、湿生及水深10、30、60、100和150cm 7个不同栽培环境下的株高、叶干重、通气组织及部分生理指标的变化进行了比较分析。发现从旱生至30cm水深环境中,黄菖蒲的株高和叶干重均逐渐增加,而在水深60cm至150cm的环境中则呈降低趋势。在水深30cm的环境中处理40d,黄菖蒲叶片通气道与横截面积比及叶片SOD活性显著高于对照和其他处理组;相对电导率及脯氨酸含量随水深及处理时间的增加基本呈上升趋势。结果表明,黄菖蒲在水深约30cm的环境中生长状况最佳;在旱生、湿生和水深10cm的环境中能够生长良好;在60cm水深环境生长比较适宜;水深超过60cm,黄菖蒲不能正常生长。     

鸢尾属部分种种子微形态特征与系统演化关系

用HITACHI S-520型扫描电子显微镜对鸢尾属植物10个种及1变种、1外类群的种子微形态进行观察、比较分析,探讨了鸢尾属植物部分种种子微形态特征分类学意义及系统演化关系。结果表明：鸢尾属植物种子表面微形态特征具有种的稳定性,与分布区无关;同一种的种子凹、凸面微形态差异很大,同一类群比较时应选择相同部位观察。所研究的鸢尾种都为网状（网纹或负网纹）文饰,种间差异明显,微形态特征可用于鸢尾属间、属下系的等级划分,但不适于种下等级鉴别。研究给出了鸢尾属植物种子表面纹饰的系统进化关系,证明了种子表面微形态对鸢尾属植物分类及系统演化关系具有重要意义。