研究红火蚁工蚁活动性的新方法—刻度图示法

应用一种新方法——刻度图示法研究红火蚁工蚁Solenopsis invicta Buren群体活动性规律,结果表明,标尺上红火蚁最高爬升高度、平均爬升高度、工蚁恢复平静时间、工蚁累计数量均随着蚁巢体积增大而增大,通过分析建立红火蚁工蚁活动性程度各指标值与蚁巢大小关系多个模型。     

研究红火蚁工蚁活动性的新方法-刻度图示法

应用一种新方法--刻度图示法研究红火蚁工蚁Solenopsis invicta Buren群体活动性规律,结果表明,标尺上红火蚁最高爬升高度、平均爬升高度、工蚁恢复平静时间、工蚁累计数量均随着蚁巢体积增大而增大,通过分析建立红火蚁工蚁活动性程度各指标值与蚁巢大小关系多个模型.     

红火蚁工蚁受侵扰的行为反应强度与蚁巢大小和侵扰强度之间的关系研究

红火蚁Solenopsis invicta Buren的防御行为是其被认定为社会性昆虫的关键特征之一。红火蚁蚁巢受到侵扰时,工蚁会快速涌出搜寻侵扰物并展开攻击。然而,蚁巢受侵扰后工蚁的行为反应与蚁巢大小和侵扰强度之间的关系有待进一步明确。为此,本研究通过野外视频记录并结合室内统计分析的方法来明确不同大小的红火蚁蚁巢受侵扰后工蚁反侵扰行为的动态过程。结果表明,蚁巢大小和受侵扰强度对蚁巢受侵扰后工蚁的反应速度具有显著影响。同等侵扰强度下,与中、大型蚁巢相比,小型蚁巢的工蚁往往表现出更慢的行为反应。尤其在低侵扰强度时,小蚁巢工蚁的反应时间平均0.8 s,而中蚁巢和大蚁巢均仅为0.34 s。当侵扰强度相同时,蚁巢越大,受侵扰后召集工蚁的数量越多;当蚁巢大小相同时,侵扰强度越高,召集工蚁的数量越多。但无论是蚁巢大小还是侵扰强度的不同,红火蚁蚁巢受侵扰后,召集工蚁的数量到达峰值的时间均为30 s左右。研究结果为进一步了解红火蚁的防御行为,科学预防红火蚁的攻击,以及有效开展红火蚁的防治提供了重要的实验依据。     

广东吴川红火蚁消长规律

采用系统调查的方法研究广东吴川红火蚁Solenopsis invicta Buren蚁巢数量、蚁丘体积和工蚁的年度变化规律,结果表明1年之中红火蚁活动蚁巢密度出现2个高峰期,分别在6~8月和10~12月;4~7月和10~11月新增活动蚁巢数量较大;蚁巢自然消亡出现在多个时间,其中以9月最多。4~11月红火蚁工蚁活动旺盛,用诱饵诱集法监测,5、6月和10、11月红火蚁工蚁出现2个明显盛期,而陷阱法中工蚁数量为单峰型,高峰出现在7月。2种监测方法获得的工蚁数量间相关系数为0.88,达到极显著相关。气温、地表温度、5cm土壤温度与2种方法获得的工蚁数量间相关系数分别为0.88,0.88,0.86和0.93,0.94,0.95,均达极显著水平。红火蚁蚁丘体积4~6月、9~12月增大幅度较大,其中6月份蚁巢增长最为明显。     

不同剂量灭蚁威饵剂对红火蚁的田间防治效果评价

【目标】明确红火蚁Solenopsis invicta Buren毒饵最佳使用剂量有助于有效控制红火蚁、降低防治成本和保护生态安全。【方法】采用活动蚁巢减退率、工蚁减退率与蚁群级别降低率综合评价了单蚁巢点施不同剂量灭蚁威饵剂对红火蚁的田间防治效果。【结果】结果表明,地表有效体积大小一致的蚁巢实施25、20、15、10、5 g饵剂处理25 d后,对应的活动蚁巢减退率分别为80%、90%、100%、90%、90%,工蚁减退率分别为100%、100%、100%、98.1%、99.2%,蚁群级别降低率为86.7%、90%、100%、80%、76.7%。同时,在最适投饵量基础上,针对不同地表有效体积大小的蚁巢投施相应饵剂量,综合防治效果达94%以上。【结论】上述结果可见,对蚁巢地表有效体积大小0.066 m~3的蚁巢施用15 g灭蚁威饵剂能起到最佳的防治效果,而且每0.03 m~3蚁巢地表有效体积大小相对应的饵剂量为5 g。     

高效氯氟氰菊酯微囊悬浮剂与二阶段法对红火蚁的田间防治效果评价

研究了高效氯氟氰菊酯微囊悬浮剂与二阶段法对红火蚁的田间防治效果。结果表明,0.25 g/L高效氯氟氰菊酯微囊悬浮剂施药后击倒红火蚁迅速,14 d后活动蚁巢减退率、工蚁减退率、蚁巢级别降低率、综合防治效果均达到100%。使用0.045%茚虫威饵剂搭配0.25 g/L高效氯氟氰菊酯微囊悬浮剂的二阶段法,5 d后红火蚁的活动蚁巢和工蚁数量均显著下降,14 d后活动蚁巢减退率、工蚁减退率、蚁巢级别降低率、综合防治效果均达到100%。结果表明,0.25 g/L高效氯氟氰菊酯微囊悬浮剂对红火蚁具有高效的控制作用,在实际使用时可根据防治面积的大小选择单独灌巢还是配合饵剂的二阶段法。     

四种毒饵对红火蚁的田间防治效果评价

采用工蚁诱测法和挖巢观察法评价了4种国产毒饵对红火蚁Solenopsis invicta的田间防治效果。结果表明,氟虫胺、胺菊酯、苯氧威、多杀霉素4种毒饵处理后,红火蚁工蚁诱集百分率均明显降低,处理5d后氟虫胺、胺菊酯的工蚁诱集率为0,而多杀霉素处理10d后诱集率为0。施药后25d4种毒饵处理活动蚁巢减退率分别为100％、100％、50％和71．4％,工蚁减退率分别为100％、100％、92．7％和100％。处理6周后蚁群级别分别降低了100％、100％、83．3％、73．0％。     

红火蚁对新入侵龙眼园和荒草地蚂蚁类群多样性的影响

于2007年7月至2008年2月期间在增城龙眼园及周边的荒草地人工移殖1蚁巢及10蚁巢红火蚁,并采用陷阱法和诱饵诱集法调查研究红火蚁对新入侵龙眼园区和荒草地区蚂蚁类群多样性的影响。结果表明,在荫蔽、少干扰的龙眼园和杂草茂密、少干扰的未割草区,红火蚁难以成功定殖,对这两种生境蚂蚁类群的多样性几乎没有影响;在红火蚁成功定殖的1蚁巢割草区和10蚁巢割草区,红火蚁以这两种密度入侵对蚂蚁类群多样性的影响程度不同。在1蚁巢割草区,红火蚁入侵后5个月期间,由于其数量占蚂蚁个体总数的比例很少,对蚂蚁类群多样性的影响很小;在红火蚁成功定殖5个月后,第6—7个月其工蚁所占比例增加,蚂蚁类群个体数和优势度下降,多样性和均匀度增加;第8—9个月其工蚁所占比例继续增加,而蚂蚁个体数、多样性和均匀度下降,优势度增加。在10蚁巢割草区,红火蚁入侵后,蚂蚁类群个体数、多样性和均匀度下降,优势度增加。红火蚁入侵对1蚁巢割草区和10蚁巢割草区蚂蚁物种数的影响较小。     

5种药剂对红火蚁的田间药效评价

以活动蚁巢减退率和工蚁减退率为指标,评价红火蚁克星（Ⅳ型）、灭蚁威、火蚁净、蚁净安和灭蚁蝗等5种药剂对红火蚁的防治效果。结果表明,不同药剂间防治效果存在差异,其中药后21 d,红火蚁克星（Ⅳ型）和灭蚁威饵剂均具有很好的防治效果,对蚁巢防效和活动工蚁的防治效果均达90.0%以上。建议采用上述两种药剂进行轮换使用,从而延缓红火蚁产生抗药性。     

广州地区红火蚁工蚁的巢外活动及有翅蚁的婚飞规律

为了阐明红火蚁Solenopsis invicta Buren的发生危害规律,为制定红火蚁的监测与防治措施提供科学依据,本研究调查了广州地区（113°45′E,22°43′N）红火蚁工蚁巢外活动日节律和季节性变化,以及有翅蚁的婚飞活动。结果表明,工蚁巢外活动日节律随季节或月份的不同而存在着明显差异：其中12-2月份的日活动节律为单峰型,即在中午温度较高时数量较大,而在5-10月份的日活动节律为双峰型,即在上午或下午工蚁数量较大,其余月份的活动为不明显的双峰型。工蚁巢外活动数量和时间随季节的不同而有显著差异。其中以6月和10月份的日活动数量最多,而在1月和2月份的活动数量最少,时间最短,其余月份活动数量居中。工蚁在阵雨前后的活动数量明显多于晴天,但处于降雨时刻的巢外工蚁数量极少。蚁巢受侵扰后出巢工蚁数量在30 s内最大,之后便随时间的延长而逐渐减少,该种现象可以用房室函数进行描述。另外,工蚁的巢外数量会随侵扰强度的加大而增加。在试验区内全年都可见到红火蚁婚飞,但婚飞活动主要集中在3-5月份,每日婚飞活动主要发生在下午,并主要发生在雨前或雨后。上述结果对于了解我国红火蚁的发生危害规律和提升其监控技术水平有较大参考价值。     

Colony‐level behavioural variation correlates with differences in expression of the foraging gene in red imported fire ants

Among social insects, colony‐level variation is likely to be widespread and has significant ecological consequences. Very few studies, however, have documented how genetic factors relate to behaviour at the colony level. Differences in expression of the foraging gene have been associated with differences in foraging and activity of a wide variety of organisms. We quantified expression of the red imported fire ant foraging gene (sifor) in workers from 21 colonies collected across the natural range of Texas fire ant populations, but maintained under standardized, environmentally controlled conditions. Colonies varied significantly in their behaviour. The most active colonies had up to 10 times more active foragers than the least active colony and more than 16 times as many workers outside the nest. Expression differences among colonies correlated with this colony‐level behavioural variation. Colonies with higher sifor expression in foragers had, on average, significantly higher foraging activity, exploratory activity and recruitment to nectar than colonies with lower expression. Expression of sifor was also strongly correlated with worker task (foraging vs. working in the interior of the nest). These results provide insight into the genetic and physiological processes underlying collective differences in social behaviour. Quantifying variation in expression of the foraging gene may provide an important tool for understanding and predicting the ecological consequences of colony‐level behavioural variation.     

Intraspecific usurpation of incipient fire ant colonies

Brood raiding, or reciprocal stealing of brood, is common amongincipient colonies of the fire ant Solenopsis invicta. Paradoxically,workers from a colony that loses its brood during a raid oftenabandon their nest and join the winning colony. Queens abandonedby their workers may then migrate from their original nest siteand attempt to forcefully usurp another incipient colony bydisplacing that colony's queen or queens. This study examinedfactors that influence the success of usurpation attempts. Queensattempting to usurp a nearby colony after laboratory brood raidswere successful in less than 30% of trials. Usurpation attemptswere more successful if workers familiar to the migrating queenwere present in the nest, as would happen if a queen were tofind the colony to which her workers had moved. Cross-fosteringexperiments showed that this effect was due to familiarity ratherthan relatedness. Usurpation attempts were less successful ifthey were delayed by 16 h. The probability of usurpation successwas not reduced by doubling the number of defending workersin the invaded colony. However, colonies founded by three queenswere almost always able to resist usurpation attempts. Theseresults support the hypothesis that workers abandon their natalcolony after losing a brood raid to increase the likelihoodthat their queen can usurp the colony to which they migrate.These results also provide the first evidence that coloniesof ants founded by several queens are better able to resistusurpation attempts than colonies founded by a single queen     

茚虫威在红火蚁工蚁间的横向接触传导效应

[背景]红火蚁是我国重要的外来入侵害虫。利用其相互清洁和交哺行为等社会性昆虫特有的生活习性,使杀虫剂在巢群内传导,可以达到全巢药剂控制的目的。然而,有关茚虫威在红火蚁巢群内的传导效应尚未见有详细报道。[方法]采用供药蚁/受药蚁模型,研究了药剂剂量、供药蚁—受药蚁比例、处理时间对茚虫威在红火蚁工蚁间横向传毒的影响。[结果]剂量越高,受药蚁的死亡率越高,25 ng·头-1处理组受药蚁死亡率为14.1%～70.0%,而50 ng·头-1处理组的受药蚁死亡率最高可达100%;供药蚁—受药蚁比例显著影响茚虫威的传毒,比例为1∶1时,50、100、250、500 ng·头-1处理组受药蚁死亡率可达100%;随着时间延长,受药蚁的死亡率升高,但在12 h后,供药蚁死亡率最高仅为8.0%,表明茚虫威具缓效特性。[结论与意义]本研究明确了在红火蚁工蚁间茚虫威横向传毒的剂量、时间和供药蚁—受药蚁比例的效应,为应用该药剂提供了依据。     

室内饲养的红火蚁工蚁毒腺生物碱含量动态分析

【目的】分析红火蚁 Solenopsis invicta 工蚁在室内长时间饲养时,体内生物碱主要成分的含量变化。【方法】每10 d取0.5 g红火蚁工蚁用正己烷溶剂浸提48 h,浸提液通过硅胶柱分离,经气相色谱（GC）和气相色谱 质谱联用仪（GC-MS）鉴定其生物碱的主要成分,并用外标法测其生物碱各个主要成分的含量。【结果】红火蚁工蚁体内生物碱主要成分为9种顺式生物碱和5种反式生物碱,并测出90 d内这14种化合物在红火蚁工蚁体内的含量变化。其中,反式生物碱2-甲基-6-（4′-十三烯）哌啶的含量最高,第1天为3 391.57 μg/g,90 d后为556.70 μg/g;顺式生物碱2-甲基-6-十五烷基哌啶的含量最低,第1天为10.27 μg/g,90 d后为2.93 μg/g。【结论】红火蚁工蚁在室内长时间饲养时,体内生物碱的含量开始时持续下降,当生物碱含量下降到一个极低的水平后,基本不再变化,处于平衡状态。结合室内饲养时红火蚁工蚁死亡情况,可推测出当红火蚁蚁巢中生物碱含量很低时,蚁巢中体型较大的工蚁数量会比较少。     

A comparison of mark–release–recapture methods for estimating colony size in the wood ant Formica lugubris

Colony size can be considered the analogue of the body size of a superorganism. Just as body size is important to the physiology of an individual animal, colony size correlates with the life-history and ecology of social insects. Although nest excavation and counting all individuals is the most accurate method for estimating colony size (or nest size), it has the major drawback of being destructive. Alternatively, mark–release–recapture (MRR) can be used repeatedly to measure the size of the same colony or nest. We compared the accuracy and feasibility of four MRR methods and a Mound-Volume method with complete counts from nest excavation for estimating the nest size of F. lugubris, a mound-building wood ant of the Formica rufa group, during the early spring in Scotland. We found that our After-Disturbing method, in which we performed marking and recapturing after gentle disturbance to the top of nest mound, has the best balance between accuracy, non-destructiveness, and time required. We also found that mound volume can be an index of ant nest size under certain conditions. Both non-destructive methods can be used on the same colony or nest repeatedly to monitor nest dynamics.     

Settlement in the prey termite nest by the ponerine antPachycondyla caffraria (Smith), and tandem running signal analysis for the following ant

The workers ofPachycondyla caffraria attack the nests of the termiteMicrocerotermes sp. in the laboratory. The hunter workers bore into the side of the nest, enter and catch the termites, and return to their nest with the captured prey. Later in the same day, all or part of the colony moves out and settles in the termite nest. The hunter workers use tandem running for the attack of the termite nest, the capture of termite and the removal of the colony to the nest which was raided. To analyse the relevant signals for the following ant during tandem running, we offered different dummies to followers which had been separated from their leader ants. The signals which release the following behaviour are a conbination of visual and chemical signals. Seventy percent of motivated followers reacted positively to paper with methanolic extract of the leader ant, 44% of motivated followers reacted positively to an odourless paper, and 100% reacted positively to a freshly killed leader ant. The leading effect of the body surface is lost by cleaning with solvents of different polarity.     

Ants under crowded conditions consume more energy

Social insects live in colonies consisting of many workers, where worker interactions play an important role in regulating colony activities. Workers interact within the social space of the nest; therefore, constraints on nest space may alter worker behaviour and affect colony activities and energetics. Here we show in the ant Temnothorax rugatulus that changes in nest space have a significant effect on colony energetics. Colonies with restricted nest space showed a 14.2 per cent increase in metabolic rate when compared with the same colonies in large uncrowded nests. Our study highlights the importance of social space and shows that constraints on social space can significantly affect colony behaviour and energy use in ants. We discuss the implications of our findings regarding social insects in general.     

Sociometry and sociogenesis of colonies of the harvester ant, Pogonomyrmex badius: distribution of workers, brood and seeds within the nest in relation to colony size and season

1. The vertical distribution in the nest of chambers, workers, callow workers, brood and seeds was studied in the harvester ant, Pogonomyrmex badius, in northern Florida. On each of four sample dates (May, July, October, January), six to seven colonies, chosen to represent the full range of sizes, were excavated. All chamber contents were collected and counted. Chambers were mapped and measured. In a preliminary study, two nests were excavated after preventing vertical migration by driving barriers into the wall of a pit next to the nest, severing the vertical tunnels. The vertical distribution of these barrier-nests differed little from unrestrained nests, indicating that unrestrained excavation produced a reasonable picture of vertical distributions. 2. Nest depth, chamber number and total area increased with colony size. Chamber area declined sharply with depth, as did chamber number, such that more than half of the total area was found in the upper quarter of the nest. 3. The proportion of dark-coloured (older) workers also declined strongly with depth, but this decline was weaker in the spring, and depended to a modest degree on colony size. Conversely, in the distribution of callow (young) workers, the proportion increased towards the bottom of the nest. Mean worker age was inversely related to the depth at which workers were found. The proportion of the brood also increased towards the bottom of the nest, with worker brood, sexual brood, pupae and larvae all being distributed similarly. 4. By contrast, seeds were stored at a preferred absolute depth between 40 and 100 cm. Colonies shallower than 100 cm stored seeds in their deepest chambers. Larger colonies stored most seeds in the upper third of the nest, but patterns were somewhat erratic because chambers were either filled completely with seeds or were empty. 5. Because chamber area decreased sharply with depth, the densities (individuals cm^–2) of all colony members, including dark workers, were lowest near the surface and highest in the deepest parts of the nest. Here, worker densities ranged from 2 to 8 cm^–2, and brood from 2 to 25 cm^–2. 6. The regularity of the patterns of distribution suggests that harvester ant colonies have considerable spatial and temporal structure, which serves or is the outcome of important colony processes. A simple mechanism that could generate several of these patterns is discussed. New workers produced deep in the nest move upwards as they age. As they leave the brood zone they change from brood care to general nest duties, including increased nest excavation, leading to the top-heavy pattern of nest area. As they appear at the surface, they change to guarding and foraging. Thus, age polyethism may be partly the result of this upward migration of workers.     

Reproductive allocation within a polygyne, polydomous colony of the ant Myrmica rubra

1. Ant colonies commonly have multiple egg‐laying queens (secondary polygyny). Polygyny is frequently associated with polydomy (single colonies occupy multiple nest sites) and restricted dispersal of females. The production dynamics and reproductive allocation patterns within a population comprising one polygyne, polydomous colony of the red ant Myrmica rubra were studied. 2. Queen number per nest increased with nest density and the number of adult workers increased with the number of resident queens and with nest density. This suggests that nest site limitation promotes polygyny and that workers accumulate in nest units incapable of budding. 3. Nest productivity increased with the number of adult workers and production per queen was independent of queen number. Productivity increased with nest density, suggesting local resource enhancement. This shows that productivity can be a linear function of queen numbers and that the limiting factor is not the egg‐laying capacity of queens. 4. The total and per capita production of reproductives decreased towards the periphery of the colony, suggesting that the spatial location of nest units affects sexual production. Thus nests at the periphery of the colony invested more heavily in new workers. This is consistent with earlier observations in plants and could either represent investment in future budding or increased defence. 5. The colony produced only five new queens and 2071 males, hence the sex ratio was extremely male biased.