白蚁的蚁客

<正> 白蚁是一类多型的、营社会生活的昆虫。白蚁巢内部常能发现许多蚁客(Termitophiles)。较低等的、蚁巢结构较简单的白蚁,其蚁客的种类和数量较少;而高等的、蚁巢结构复杂、特别是具有菌圃的蚁巢,其中蚁客的种类和数量也较多。 作者近年来(1975—1979)在浙江有关地区白蚁防治单位的协助下,自尖叉原白蚁、黑胸散白蚁、家白蚁、屏南象白蚁、黑翅土白蚁及黄翅大白蚁等6种蚁巢内,采集到30多种蚁客。经初步鉴定,它们隶属于节肢动物门中3个纲、9个目、16个科。其中以昆虫纲的种类最为丰     

开发昆虫新资源──浅谈白蚁的搜集

昆虫资源开发是近几年来研究的一项新课题,昆虫学家充分肯定了部分昆虫体内含有多种营养物质,并应加以开发。目前,对昆虫资源开发的文章时有发表,但对昆虫资源搜集方面的情况从未见过报道,现将如何搜集白蚁和进行初步加工的方法整理如下。1家白蚁Coptotermesspp．的搜集白蚁是社会性昆虫,行动诡秘,破坏性惊人,特别是家白蚁对建筑物的破坏更大,一旦发现家白蚁,往往会造成人心惶惶,令人深恶痛绝。家白蚁习惯将蚁巢建于大树底部和土木交接处,质地结实,这为家白蚁搜集提供了定位巢穴的线索。家白蚁蚁巢一经发现,迅速将蚁巢连同白…     

云南大白蚁亚科白蚁分飞情况及与蚁巢伞关系

在云南绿春观察大白蚁亚科4种土白蚁的分飞活动,研究大白蚁亚科白蚁和蚁巢伞之间的关系,得知:大白蚁亚科不同种类白蚁分飞孔形状不相同,分飞时分布于孔口周围的白蚁型、数目和扩散范围存在差异,这些蚁巢的外露特征可以作为白蚁种类识别的辅助依据。采集32巢白蚁以及其巢上生长的蚁巢伞,结果显示,大白蚁亚科每一个白蚁巢仅生长一种蚁巢伞Termitomyces子实体。与小果蚁巢伞共生的白蚁也与其他蚁巢伞共生,推测真菌能改变白蚁的行为。对白蚁种类和蚁巢伞种类对应关系的研究表明在小地域内,白蚁和蚁巢伞不仅存在属间高度专一性,而且种间也显示较高的共生专一性。     

白蚁采食行为中的信息交流

白蚁作为社会性昆虫, 其采食个体间依赖各种信息交流机制进行联系与协作, 其中包括踪迹、 警戒、 食物信息、 同伴识别和助食等。通常的联系信号为挥发性或半挥发性化学物质或者一定频谱和功率的机械振动波。其中踪迹信息素、 蚁源烃类、 警戒信息素、 助食素和机械振动信号等都在白蚁采食过程中起着重要作用。白蚁采食过程中食物定向和食物品质信息的传达主要依靠腹板腺分泌的踪迹信息素, 已发现有十二碳烯醇类、 降碳倍半萜类和大环二萜类。蚁源的机械振动也在食物品质表达方面起到一定作用, 但食物品质的表达机制还不明确。白蚁采食协作的基础是同伴识别, 蚁源烃类（C21~C35）是同伴识别的主要信息物质, 采食个体分泌的助食素则可促成共同取食。警戒信息素传递白蚁采食的安全信息, 通常为一些兵蚁源的萜类物质, 但得到功能鉴定的结构还不多。近来研究还发现特殊的蚁源机械振动也可起到示警作用。已初步证实各种信息交流机制间存在交互作用, 但交互作用的机理有待进一步解析。生物物理因素在白蚁采食行为中的作用值得更多重视。本文以白蚁的采食行为为线索, 评述白蚁采食个体间信息交流机制的研究进展及利用问题, 并对今后的研究提出展望。     

三种天然饵料对两种白蚁的野外诱食效果

为筛选一种容易取材、价格低廉且诱食效果较佳的天然饵料,在野外测定了隆缘桉树皮、杉树皮和甘蔗渣三种饵料对黑翅土白蚁和黄翅大白蚁的诱食效果。结果表明在非选择性取食试验中,桉树皮、杉树皮和甘蔗渣在埋插后15 d的诱食率为84.26%、77.78%和8.33%;在选择性取食试验中,桉树皮、杉树皮和甘蔗渣在埋插后15 d的诱食率为87.04%、81.48%和9.26%。在两种试验条件下,桉树皮和杉树皮对两种白蚁均有较好的诱食效果,且两者之间的差异不显著,甘蔗渣对两种白蚁的诱食效果较差。     

白蚁防治中引诱技术的应用

白蚁是一类危害面广、破坏性极大的世界性害虫。利用各种防治技术控制白蚁危害由来已久,引诱技术乃其中一种。采用引诱技术具有防治成本低、针对性强、效果显著、对生态环境破坏性小等优点。白蚁是社会性昆虫,其行为有利于我们采用引诱技术实施防治。引诱技术包括饵诱法、信息素引诱法、灯诱法等具体方法,本文主要介绍饵诱法和信息素引诱法应用情况及研究进展。１饵诱法食物引诱是最古老、最简单易行的引诱方法。其采用３种方式：（１）诱集．杀灭：在白蚁活动区域设置白蚁喜食饵料（堆、坑）诱其前来取食,然后用烫、烧、踩、喂鸡和药杀…     

白蚁信息素研究进展

白蚁是最古老的社会性昆虫, 其社会性的维持需要信息素的相互作用。本文回顾了近年来国内外白蚁信息素研究的最新进展, 内容涉及白蚁踪迹信息素、 性信息素、 告警信息素和促食信息素的功能、 化学成分及产生信息素的外分泌腺。白蚁分泌信息素的腺体主要有背板腺、 腹板腺、 后腹板腺、 额腺和唾腺。绝大多数白蚁信息素是挥发性物质。白蚁在化学通讯上存在节俭策略, 即同一种化合物由不同的白蚁种类的不同外分泌腺分泌, 可具有不同的功能。总结了各类信息素在白蚁物种间、 同一物种的品级间和性别间的异同和作用方式, 强调了白蚁信息素的反应阈值、 最佳浓度、 有效期和物种特异性对其功能的影响。目前对白蚁信息素的研究尚处于起步阶段, 其研究成果对等翅目系统发育研究和白蚁防治具有重要的意义。文章最后展望了白蚁信息素在白蚁防治上的应用前景。     

小头钩白蚁巢结构研究

【目的】了解小头钩白蚁Ancistrotermes dimorphus Tsai et Chen的蚁巢结构、各品级在腔室中的分布和巢群个体数量,为有效防控该种白蚁提供科学依据。【方法】采用蚁巢定位和巢体结构解剖法研究蚁巢结构;采用统计法确定各品级在腔室中的分布和巢群个体数量。【结果】小头钩白蚁巢由腔室、菌圃、蚁路、王室、候飞室和分飞孔六部分组成;巢群个体数量为12 255~24 230头(含卵粒);卵、幼蚁、若蚁、工蚁、兵蚁和有翅成虫分散分布在蚁巢腔室中,并不集中于某一特定区域。【结论】小头钩白蚁巢属于极端分散类型,巢群个体数量较少。     

昆虫产卵驱避激素的研究概况

<正> 许多研究结果表明,昆虫能通过接受和感觉“驱散信息素”(deterring semiochemical)来识别已被占领的食物资源。在某些昆虫中,此类信息素能阻止同种个体在已被占领的食物资源上停留或取食;在另一些昆虫中,则能阻止雌成虫在同一位置再次产卵。这种阻止产卵的信息素称为产卵驱避素(oviposition—deterring pheromone,简称ODP)。在有些昆虫中,ODP是由雌成虫在产卵时释放出来的,并附着于卵     

小头钩白蚁巢结构研究

【目的】了解小头钩白蚁Ancistrotermes dimorphus Tsai et Chen的蚁巢结构、各品级在腔室中的分布和巢群个体数量,为有效防控该种白蚁提供科学依据。【方法】采用蚁巢定位和巢体结构解剖法研究蚁巢结构;采用统计法确定各品级在腔室中的分布和巢群个体数量。【结果】小头钩白蚁巢由腔室、菌圃、蚁路、王室、候飞室和分飞孔六部分组成;巢群个体数量为12 255~24 230头(含卵粒);卵、幼蚁、若蚁、工蚁、兵蚁和有翅成虫分散分布在蚁巢腔室中,并不集中于某一特定区域。【结论】小头钩白蚁巢属于极端分散类型,巢群个体数量较少。     

白蚁踪迹信息素研究进展

近年来, 固相微萃取技术的使用显著促进了白蚁踪迹信息素研究的开展。目前, 已有77种白蚁的踪迹信息素得到研究, 常见化学成分为十二碳单烯醇、 十二碳二烯醇和十二碳三烯醇, 其次为新松柏烯。已经鉴定的踪迹信息素主要为单组分或双组分系统。白蚁踪迹信息素由腹板腺分泌, 除澳白蚁科的达氏澳白蚁Mastotermes darwiniensis具有3个腹板腺外, 现存的白蚁均具有1个腹板腺, 位于第4或第5腹节。所有腹板腺都具有类型Ⅰ和Ⅱ两类细胞, 原白蚁亚科（Termopsinae）、 齿白蚁科（Serritermitidae）、 鼻白蚁科（Rhinotermitidae）种类的腹板腺还具有类型Ⅲ细胞。踪迹信息素的生物合成还缺乏研究, 推测有甲羟戊酸、 脂肪醇和饱和表皮烃3种途径。白蚁踪迹信息素的简约性十分显著, 不同地理分布、 生物生态习性以及一些系统距离较远的种类具有相同和密切相关的踪迹信息素。对于许多种类, 相同的信息化合物具有踪迹信息素和配对性信息素双重功能。白蚁踪迹信息素种特异性和简约性的适应意义和进化机制需要进一步研究。     

Colony‐age‐dependent variation in cuticular hydrocarbon profiles in subterranean termite colonies

Cuticular hydrocarbons (CHCs) have, in insects, important physiological and ecological functions, such as protection against desiccation and as semiochemicals in social taxa, including termites. CHCs are, in termites, known to vary qualitatively and/or quantitatively among species, populations, castes, or seasons. Changes to hydrocarbon profile composition have been linked to varying degrees of aggression between termite colonies, although the variability of results among studies suggests that additional factors might have been involved. One source of such variability may be colony age, as termite colony demographics significantly change over time, with different caste and instar compositions throughout the life of the colony. We here hypothesize that the intracolonial chemical profile heterogeneity would be high in incipient termite colonies but would homogenize over time as a colony ages and accumulates older workers in improved homeostatic conditions. We studied caste‐specific patterns of CHC profiles in Coptotermes gestroi colonies of four different age classes (6, 18, 30, and 42 months). The CHC profiles were variable among castes in the youngest colonies, but progressively converged toward a colony‐wide homogenized chemical profile. Young colonies had a less‐defined CHC identity, which implies a potentially high acceptance threshold for non‐nestmates conspecifics in young colonies. Our results also suggest that there was no selective pressure for an early‐defined colony CHC profile to evolve in termites, potentially allowing an incipient colony to merge nonagonistically with another conspecific incipient colony, with both colonies indirectly and passively avoiding mutual destruction as a result.     

Interaction of pheromones during food exploitation by the termite Schedorhinotermes lamanianus

Abstract. Chemical signals from secretions of different exocrine glands modulate a variety of behavioural patterns in termite societies. These signals have multiple functions and may be interactive. During food exploitation workers of the African termite Schedorhinotermes lamanianus (Isoptera: Rhinotermitidae) employ, on foraging trails, the secretion from the sternal gland both for orientation and recruitment to a food source. The secretion from the labial gland, released onto the food by gnawing termites, stimulates additional workers to gnaw at the same site, thereby forming aggregations of gnawing termites. An interaction between these two pheromones during food exploitation is demonstrated for the first time. The volatile signal from the sternal gland inhibits in a dose-dependent manner the non-volatile, highly persistent, signal from the labial gland. The development of gnawing aggregations is inhibited and established ones are dissolved. Behavioural evidence for the perception of both the volatile signal from the sternal gland by olfactory neurones and of the non-volatile signal from the labial gland by gustatory neurones on the antennae is given. The interaction of the two pheromones as a basis for the development of distinct commuting and gnawing zones on the food source, and as a means for a dynamic regulation of food exploitation, is discussed.     

Simulation study to determine why only some termites are active during tunneling activity

It has been known that some termites are responsible for tunnel excavation for foraging, while others are not involved in the excavation. The biological reason for this is that the resting termites are a backup for the termites that have used up their energy in the tunneling activity. In this study, we build an agent‐based model (ABM) wherein agents (simulated termites) follow simple rules that govern their behavior. In this model, the agents are endowed with a directional vector that has been shown to exist in real termites, but they do not communicate through pheromonal or physical marking of excavation sites. They move toward the tunnel tips, tunnel when their progress in that direction is blocked, and transport the excavated soil. Using the model, we investigated the work efficiency of termites in constructing tunnels and transporting food; the efficiency was defined as the inverse value of tunnel connectivity plus tunnel expansion speed. Biologically, the connectivity is related to the energy to be used for termites to transport food through tunnels, and the tunnel expansion speed is related to the energy required for constructing tunnels. Simulation results showed that the efficiency was maximized at an intermediate number of termites. This means that termites were better to be inactive to maintain the high efficiency when too many workers are present in the colony. We briefly discuss the strength and weakness of the ABM and the values of this study in relation to termite foraging strategy.     

When subterranean termites challenge the rules of fungal epizootics

Over the past 50 years, repeated attempts have been made to develop biological control technologies for use against economically important species of subterranean termites, focusing primarily on the use of the entomopathogenic fungus Metarhizium anisopliae. However, no successful field implementation of biological control has been reported. Most previous work has been conducted under the assumption that environmental conditions within termite nests would favor the growth and dispersion of entomopathogenic agents, resulting in an epizootic. Epizootics rely on the ability of the pathogenic microorganism to self-replicate and disperse among the host population. However, our study shows that due to multilevel disease resistance mechanisms, the incidence of an epizootic within a group of termites is unlikely. By exposing groups of 50 termites in planar arenas containing sand particles treated with a range of densities of an entomopathogenic fungus, we were able to quantify behavioral patterns as a function of the death ratios resulting from the fungal exposure. The inability of the fungal pathogen M. anisopliae to complete its life cycle within a Coptotermes formosanus (Isoptera: Rhinotermitidae) group was mainly the result of cannibalism and the burial behavior of the nest mates, even when termite mortality reached up to 75%. Because a subterranean termite colony, as a superorganism, can prevent epizootics of M. anisopliae, the traditional concepts of epizootiology may not apply to this social insect when exposed to fungal pathogens, or other pathogen for which termites have evolved behavioral and physiological means of disrupting their life cycle.     

Worker aggression of ant Lasius japonicus enhanced by termite soldier–specific secretion as an alarm pheromone of Reticulitermes speratus

The subterranean termite Reticulitermes speratus usually nests in rotten wood trunks, which may also be occupied by the Japanese garden ant Lasius japonicus. Few battles were observed between them under ordinary circumstances because they inhabit separate nesting sites. However, once the termite nesting sites were artificially broken, the ant workers invaded and hunted the termites, although the termite soldiers fought against the ants. This study aims to confirm intra‐ and inter‐specific chemical interactions between the termite and ant. Solid phase microextraction–gas chromatograph (SPME‐GC) analyses revealed that R. speratus soldiers secreted caste‐specific sesquiterpene hydrocarbon when they were irritated. Both the hexane extract of the soldiers and its hydrocarbon fraction, as well as the crushed soldier bodies, attracted the soldiers but dispersed the workers when presented on the trails. We also confirmed that the soldier chemicals enhanced aggressiveness of L. japonicus, which rushed around the odor sources and hunted any termites that were present. These findings suggest that: (i) the soldier–specific secretion might serve as an alarm pheromone in termite chemical communication, in which components recruit soldiers and also warn the other colony members away; and (ii) termite communication is eavesdropped on by L. japonicus workers to locate and hunt the termites.     

Chemical warfare in termites

The rapid development of analytical methods in the last four decades has led to the discovery of a fascinating diversity of defensive chemicals used by termites. The last exhaustive review on termite defensive chemicals was published by G.D. Prestwich in 1984. In this text, we aim to fill the gap of the past 25 years and overview all of the relevant primary sources about the chemistry of termite defense (126 original papers, see Fig. 1 and online supplementary material) along with related biological aspects, such as the anatomy of defensive glands and their functional mechanisms, alarm communication, and the evolutionary significance of these defensive elements.