茶叶挥发物对白斑猎蛛觅食行为的影响

为了探明茶树叶片挥发物在白斑猎蛛(Evarcha albaria)选择觅食斑块过程中的作用,采用固相微萃取-气相色谱-质谱联用技术研究了其猎物假眼小绿叶蝉(Empoasca vitis)取食对茶树叶片挥发物释放的影响,同时利用蜘蛛行为观测平台研究了白斑猎蛛在不同味源侧(觅食斑块)的活动行为。结果表明,未损伤叶片(对照)仅释放出微量挥发物,而假眼小绿叶蝉成虫取食后的茶树叶片释放出14种挥发物;雌、雄蛛在进入处理味源(假眼小绿叶蝉取食后的茶树叶片)侧和对照侧的初次选择及进入频次上均无显著差异,但与对照相比,雌、雄蛛在虫害处理叶片中的停留时间显著增加。研究表明,假眼小绿叶蝉取食诱导了茶树叶片挥发物的释放,而挥发物种类和含量的变化造成了白斑猎蛛在不同味源侧停留时间的差异。     

鄱阳湖南矶湿地国家级自然保护区2种大雁的越冬行为特征及生态位分化

2014年12月至2015年3月,对鄱阳湖南矶湿地国家级自然保护区越冬的鸿雁(Anser cygnoides)和白额雁(Anser albifrons)的行为模式和生境选择进行调查。结果显示,鸿雁和白额雁均以静栖和觅食行为为主,鸿雁的静栖行为比例最大,白额雁的觅食行为比例最大;鸿雁的静栖行为比例极显著高于白额雁,觅食行为比例极显著低于白额雁,警戒和游走行为比例低于白额雁。在行为节律上,鸿雁的觅食高峰出现在14:00—15:00,静栖高峰出现在13:00—14:00;白额雁的觅食行为比例在8:00—9:00、11:00—12:00和16:00—17:00这3个时段较高,静栖行为比例在10:00—11:00、12:00—13:00和16:00—17:00这3个时段较高。觅食时间上的"错峰"将减轻两者对食物资源的激烈竞争以达到共存。在生境的空间选择上,鸿雁的生境选择和离岸距离生态位宽度均高于白额雁,2种大雁的离岸距离生态位重叠度较大,鸿雁主要选择浅水和泥滩,白额雁主要选择草地,2种大雁对生境的离岸距离均集中选择在400~500 m区间。2种大雁生境类型选择的分化避免了离岸距离生态位重叠度较大带来的种间竞争,利于种间共存。2种大雁生境的离岸距离主要选择在400~500 m区域,这既利于2个物种避免人为干扰,又可满足自身对食物资源的需求。     

宁陕野化放飞朱鹮秋冬季日间活动时间分配和节律

于2008年9月～2009年1月采用瞬时扫描取样法在陕西省宁陕县的寨沟和华严两地对野化放飞朱鹮(Nipponia nippon)秋冬季日间活动的时间分配和活动节律进行调查和统计分析.结果表明:觅食、维护和休息是两地朱鹮秋冬季占主要活动时间的行为,而且各时间段中各种行为的时间分配存在极显著差异(F=5.822～481.74,P=0.000).在寨沟,朱鹮没有明显的取食高峰,但是有两个明显的维护高峰;而在华严,朱鹮有2个取食高峰和3个维护高峰.朱鹮在晴天和雨雪天各种行为类型的活动时间分配也有明显差异,晴天觅食的节律性不显著,而雨雪天呈现2个取食高峰.成体和亚成体活动时间分配仅在互动行为上差异极显著(P=0.000).各种干扰对朱鹮的觅食行为有较大的不利影响.     

灰鹤在天山木扎提河湿地越冬及行为观察

于2017年10月—2019年5月,采用直接计数法、瞬时扫描取样法、卫星跟踪和最小凸多边形法(MCP),对新疆阿克苏地区拜城县木扎提河流域灰鹤(Grus grus)的种群特征、活动范围、行为时间分配和行为节律进行调查和分析。结果表明,2019年越冬灰鹤种群数量超过4 700只,较2016年增加1倍多,种群发展动态呈上升趋势。灰鹤主要以家庭群为主(63.90%),聚集群次之(28.62%),孤鹤最少(7.48%)。家庭群主要以2成鸟1幼鸟为主(占46.82%),聚集群以5～8只个体为主(占65.91%)。整个越冬期持续140～160 d,灰鹤越冬期活动距离为1 058 km,活动区域相对固定,活动区域面积为125 km~2。日活动面积和活动距离随着气温的变化而变化,温度降低,日活动范围和活动距离降低;反之,则增加。因此,活动面积和活动距离呈凹形变化,即先增加(10—11月),再逐渐减少(12—1月),然后增加(2—3月)的变化趋势。取食和警戒是灰鹤的主要越冬行为。灰鹤的46.8%日间时间用于取食,17.8%的日间时间用于警戒,用于休息、走动、理羽和其他行为的日间时间分别占13.4%、11.4%、7.4%和3.2%。日取食高峰呈双凸型,出现在8:00—9:00和17:00—18:00,分别达到57.0%和58.5%。休息高峰出现在11:00—15:00,占24.6%,呈单峰型。研究区灰鹤种群面临着放牧、农耕、天敌、道路车辆、低温和人为驱赶等诸多威胁因素。     

基于红外相机技术的川金丝猴地面活动监测

川金丝猴(Rhinopithecus roxellana)属猴科(Cercopithecidae)疣猴亚科(Colobinae),但与疣猴亚科大多数物种的树栖习性不同,川金丝猴在生活史过程中展现出一定的地栖性。为了解该物种下地活动的节律、行为分布和性别-年龄组成,采用红外相机技术对四川省白水河国家级自然保护区内野生川金丝猴种群的地面活动进行了长期监测。2013—2018年共建立了70个红外相机监测位点,获得86次川金丝猴地面活动的独立捕捉,涉及243只个体。分析结果显示:(1)川金丝猴会在白昼的任何时间下地活动,11:00和19:00为一天中2个下地活动的高峰时段,而17:00为低谷期;(2)夏季川金丝猴下地活动较频繁,冬季则极少;(3)60%以上的个体都在地面进行移动行为,约30%的个体在休息,取食行为仅观察到2例;(4)地面活动个体的成年猴雌雄性比为1.21∶1,成年猴与未成年猴比为4.09∶1。本研究结果表明,移动是猴群地面活动的主要行为内容,并且下地倾向在性别和年龄间存在差异,支持了川金丝猴下地的主要目的是为了穿越林冠不连续区域的假说。     

圈养马麝(Moschus sifanicus)非繁殖季节行为特征及行为节律的性别间差异

采用比较研究法，分析了甘肃兴隆山麝场圈养马麝（Moschus sifanicus）的非交配季节（8—10月）行为特征的性别间差异，并探讨了行为模式的变化格局．结果表明，由于雌麝在非交配季节正处于哺乳期，育幼投资相对增加，警戒性增强，其静卧、摄食和反刍等行为的终止阈值下降；和雄麝相比，雌麝的站立凝视、静卧、摄食和反刍等行为的发生频次相对较多．育幼直接导致雌麝相互间的冲突行为频次增多，母幼间的行为联系使其亲和行为的表达频次多于雄麝．圈养马麝在非交配季节的月行为节律变化还存在性别差异，在8—9月间，雌麝表达的静卧和反刍行为的频次渐少，而由于雄麝8月后正处于泌香后期（成体）或泌香期（亚成体），因此其运动频次较少，卧息较多，摄食持续时间减少．随繁殖季节的临近，雄麝从8月到10月间的运动、尾阴探究、冲突行为、环境探究等动态行为的表达逐渐增加．图1表2参22     

贡嘎山高低海拔上优势杨柳科植物性别比例与繁殖特性北大核心CSCD

雌雄异株植物的性比问题一直是进化生物学的研究热点之一.为揭示杨柳科植物不同性比格局的内在机理,从繁殖投入、种群密度和传粉效率等方面对贡嘎山两个海拔高度（2 000和2 600 m）上冬瓜杨和川滇柳的性别比例与繁殖投入进行对比研究.结果显示：（1）低海拔下冬瓜杨和川滇柳雄雌性比（M/F）接近1：1平衡;而在高海拔区域出现性比失衡,即杨树偏雄（M/F=2.36,P=0.008）,而柳树偏雌（M/F=0.62,P=0.033）.（2）冬瓜杨和川滇柳种群密度随海拔升高均明显下降,但川滇柳密度显著高于冬瓜杨,柱头接收花粉数量亦显著高于冬瓜杨.（3）枝条水平上,杨柳的总繁殖结构生物量（花序干重＋种子干重）在两个海拔上都为雌株高于雄株;相对繁殖投入在低海拔时雌株高于雄株,高海拔上冬瓜杨雌株高于雄株,而川滇柳由于叶片的补偿生长,包括更高的叶片生物量投入和光合能力,导致相对繁殖投入雌雄间无显著差异.冬瓜杨雌株繁殖投入显著高于雄株,雌株对高海拔更敏感,因而高海拔时偏雄性.川滇柳的繁殖投入在海拔间无差异,加之传粉效率较高,可能容易产生花粉管竞争,从而偏雌性.本研究发现较之低海拔,贡嘎山上杨柳科植物在高海拔上叶与繁殖结构生物量权衡关系改变容易导致性比失衡,未来需在分子水平上,结合性别决定基因、性染色体和表观遗传学等进一步深入研究.     

食物和繁殖对蓝尾石龙子储能的影响

在实验室常温条件下 ,测定了蓝尾石龙子禁食雄体、喂食雄体、繁殖雌体及非繁殖雌体去尾躯干、尾、肝脏和腹脂肪体内的脂肪储存量 .结果是 :喂食雄体各储能部位脂肪能量显著高于禁食雄体 ,其中 ,腹脂肪体和尾脂肪能量差异尤为显著 ,喂食雄体腹脂肪体和尾脂肪储存量分别为禁食雄体的 11.4倍和 6 .4倍 ;非繁殖雌体各储能部位能量显著高于繁殖雌体 ,差异最大的部位是腹脂肪体和尾 ,非繁殖雌体腹脂肪体和尾贮存脂肪分别为繁殖雌体的 5 .5倍和3.3倍 .这些结果表明 :尾和腹脂肪体是蓝尾石龙子的主要储能部位 ;食物条件能显著影响体内能量储存量 ;尾和腹脂肪体内储存能量对雌体繁殖具有重要作用 .图 2表 2参 2 0     

微尾鼩种群繁殖的年龄和季节特征

2003年9月～2004年8月对四川南充地区微尾鼩种群不同年龄组繁殖的差异以及各年龄组在不同季节的差异进行研究.结果表明,微尾鼩总性比为1.05,经χ2检验,两性差异不显著,繁殖个体性比为1.08,两性差异不显著.雄性微尾鼩1、2月份各年龄组的睾丸大小(长径与短径)和重量差异不显著,3～12月份差异极显著.微尾鼩各年龄组睾丸大小和重量在12mo内季节变化为1、2月差异均不明显,3～12月份未成体组(Ⅰ)季节变化明显,而成体Ⅰ组(Ⅱ)和成体Ⅱ组(Ⅲ)差异不明显.雌性子宫斑数在1～10之间,平均胎仔数为4.05±0.14只(N=76),4、9月份为繁殖高峰期,繁殖指数分别为2.37和1.45,4～10月份成体Ⅰ组(Ⅱ)和成体Ⅱ组(Ⅲ)的繁殖力和平均胎仔数年龄差异不明显,成体Ⅱ组(Ⅲ)繁殖力和平均胎仔数在4～12月份季节变化不显著.1、2月份均为雌雄微尾鼩非繁殖期,3～12月份为繁殖期.表2参24     

贡嘎山高低海拔上优势杨柳科植物性别比例与繁殖特性

雌雄异株植物的性比问题一直是进化生物学的研究热点之一.为揭示杨柳科植物不同性比格局的内在机理,从繁殖投入、种群密度和传粉效率等方面对贡嘎山两个海拔高度(2 000和2 600 m)上冬瓜杨和川滇柳的性别比例与繁殖投入进行对比研究.结果显示:(1)低海拔下冬瓜杨和川滇柳雄雌性比(M/F)接近1:1平衡;而在高海拔区域出现性比失衡,即杨树偏雄(M/F=2.36,P=0.008),而柳树偏雌(M/F=0.62,P=0.033).(2)冬瓜杨和川滇柳种群密度随海拔升高均明显下降,但川滇柳密度显著高于冬瓜杨,柱头接收花粉数量亦显著高于冬瓜杨.(3)枝条水平上,杨柳的总繁殖结构生物量(花序干重+种子干重)在两个海拔上都为雌株高于雄株;相对繁殖投入在低海拔时雌株高于雄株,高海拔上冬瓜杨雌株高于雄株,而川滇柳由于叶片的补偿生长,包括更高的叶片生物量投入和光合能力,导致相对繁殖投入雌雄间无显著差异.冬瓜杨雌株繁殖投入显著高于雄株,雌株对高海拔更敏感,因而高海拔时偏雄性.川滇柳的繁殖投入在海拔间无差异,加之传粉效率较高,可能容易产生花粉管竞争,从而偏雌性.本研究发现较之低海拔,贡嘎山上杨柳科植物在高海拔上叶与繁殖结构生物量权衡关系改变容易导致性比失衡,未来需在分子水平上,结合性别决定基因、性染色体和表观遗传学等进一步深入研究.     

Rapid,recurring, structured survey versus bioblitz for generating biodiversity data and analysis with a multispecies abundance model

A bioblitz inexpensively and quickly generates biodiversity data, but bioblitzes are often conducted with haphazard, unreplicated sampling. Results tend to be taxonomically, geographically, or temporally biased, lack metadata, and consist of lists of observed taxa that do not enable further analyses or correction for imperfect detection. A rapid, recurring, structured survey (RRSS) uses a structured sampling design and temporal and spatial replication to survey randomly selected sites on a conservation property. We participated in a loosely structured bioblitz and a subsequent RRSS at Big Canoe Creek Nature Preserve in Springville (St. Clair County), Alabama (USA) to compare observed richness derived from the 2 survey approaches. The RRSS data structure enabled us to fit models that accounted for imperfect detection to estimate abundances, occupancy probabilities, and habitat associations. The loosely structured bioblitz data could not be used in such models. We present a new integrated multispecies abundance model that we applied to avian RRSS data. Our model extension enables estimation for the community, employs data augmentation to estimate the number of undetected species, and incorporates covariates. The RRSS generated a more comprehensive and less biased list of observed taxonomic richness than the loosely structured bioblitz (e.g., 73 vs. 45 bird species and 104 vs. 63 insect families from the RRSS vs. loosely structured bioblitz, respectively). Models fit to the RRSS data identified seasonal patterns in avian community composition and allowed for estimation of habitat–occupancy relationships for insect taxa. The RRSS protocol has potential for broad transferability as a standardized, quick, and inexpensive way to inventory biodiversity and estimate ecological parameters while providing an outreach opportunity.     

Compliance with and ecosystem function of biodiversity offsets in North American and European freshwaters

Land-use change via human development is a major driver of biodiversity loss. To reduce these impacts, billions of dollars are spent on biodiversity offsets. However, studies evaluating offset project effectiveness that examine components such as the overall compliance and function of projects remain rare. We reviewed 577 offsetting projects in freshwater ecosystems that included the metrics project size, type of aquatic system (e.g., wetland and creek), offsetting measure (e.g., enhancement, restoration, and creation), and an assessment of the projects’ compliance and functional success. Project information was obtained from scientific and government databases and gray literature. Despite considerable investment in offsetting projects, crucial problems persisted. Although compliance and function were related to each other, a high level of compliance did not guarantee a high degree of function. However, large projects relative to area had better function than small projects. Function improved when projects targeted productivity or specific ecosystem features and when multiple complementary management targets were in place. Restorative measures were more likely to achieve targets than creating entirely new ecosystems. Altogether the relationships we found highlight specific ecological processes that may help improve offsetting outcomes.     

Representation of the world's biophysical conditions by the global protected area network

Protected areas (PAs) are often implemented without consideration of already existing PAs, which is likely to cause an overrepresentation of certain biophysical conditions. We assessed the representativeness of the current PA network with regard to the world's biophysical conditions to highlight which conditions are underprotected and where these conditions are located. We overlaid terrestrial and marine PAs with information on biophysical conditions (e.g., temperature, precipitation, and elevation) and then quantified the percentage of area covered by the PA network. For 1 variable at a time in the terrestrial realm, high temperature, low precipitation, and medium and very high elevation were underrepresented. For the marine realm, low and medium sea surface temperature (SST), medium and high sea surface salinity (SSS), and the deep sea were underrepresented. Overall, protection was evenly distributed for elevation across the terrestrial realm and SST across the marine realm. For 2 variables at a time, cold and very dry terrestrial environments had mostly low protection, which was also the case for low SST and low and medium SSS across most depths for marine environments. Low protection occurred mostly in the Sahara and the Arabian Peninsula for the terrestrial realm and along the Tropic of Capricorn and toward the poles for the marine realm. Although biodiversity measures are of prime importance for the design of PA networks, highlighting biophysical gaps in current PAs adds a frequently overlooked perspective. These gaps may weaken the potential of PAs to conserve biodiversity. Thus, our results may provide useful insights for researchers, practitioners, and policy makers to establish a more comprehensive global PA network.     

Quantitative composition of the defensive secretion ofBledius species (Coleoptera: Staphylinidae: Oxytelinae) is adapted to naturally occurring predators

Summary The adaptation of defensive secretions to their target organisms was examined for the abdominal gland secretions ofBledius furcatus, B. spectabilis andB. arenarius. Therefore the target organisms of the secretion of theseBledius species (i.e. their predators) had to be identified. At the collection sites examined these were the earwigLabidura riparia, the antCataglyphis bicolor, the flyLispe candicans, different carabids of the generaPogonus, Dichirotrichus, Dyschirius, Bembidion andCalathus and the wading birdsHaematopus ostralegus andCalidris alba. The secretion of the abdominal glands contains the toxin ptoluquinone dissolved in either-dodecalactone and 1-undecene (B. furcatus andB. spectabilis) or in octanoic acid and octyloctanoate (B. arenarius). The ratio of these solvents is species-specific. Application experiments using some of the natural insect predators (L. riparia, C. bicolor, Pogonus, Di. gustavii, Dyschirius) revealed that these solvent ratios provided a more effective deterrent than other possible ratios. Thus by combining the solvents in certain ratios, the capability of cuticular penetration and therefore the effectiveness of the defensive secretions are adapted to their natural targets.     

Democracy versus development: New urban debates

The politics of development includes subtexts of choice, as underpinned by community consensus (or lack of it), against the larger backdrop of a liberal democracy, with its intricate power structures that influence the choice of concepts and often lead to complicity rather than consent. A dilemma exists between the understanding of field-level practitioners and that of academics, whose understandings of progress differ. Progress can (and often does) imply long-term change across generations whereas development is often more a matter of crisis management and delivering tangible results to end-users. This makes it a bone of contention across political systems, irrespective of local or global dynamics. Development can emerge as a tool to be wielded for power and further political mileage at the expense of progress. Progress cannot be studied as a counterpoint to development as the sense of history is often missing in development interventions. Development tends to be piecemeal as its very logic often stems from the rationale of power. This is not to suggest, however, that development is only about politics; it is definitely more than the politics of everyday life and involves all of civil society that requires its critical and immediate attention. In this sense, it has become a priority for politicians with an underlying agenda designed to out-manouevre dissent and all statements of protest.     

A palaeo-hydrogeological model for arsenic contamination in southern and south-east Asia

An argument is presented in which areas of natural arsenic contamination of modern groundwaters throughout Asia have a common origin. Arsenic originally accumulated in oceanic ferro-manganoan sediments of the eastern Palaeo-Tethys. This was further concentrated through oceanic crustal extinction in what later became the south-east Chinese accreted mineralised terrain. Proto-Himalayan uplift of this area created the palaeo-drainage systems of the Ganges – Brahmaputra, Irrawaddy, Mekong, and Red Rivers, with consequent headwater erosion of arsenic-rich sediments. Their downstream deposition as immature and easily redistributed Neogene sandstones, silts, and iron-rich clays has created secondary and tertiary reservoirs of adsorbed and authigenic arsenic, from which the current arsenic-rich groundwaters have evolved. Considering river basins within the above palaeo-hydrogeological framework provides a basis for assessing the risk of arsenic in groundwater basins of south and south-eastern Asia.     

A framework to measure the wildness of managed large vertebrate populations

As landscapes continue to fall under human influence through habitat loss and fragmentation, fencing is increasingly being used to mitigate anthropogenic threats and enhance the commercial value of wildlife. Subsequent intensification of management potentially erodes wildness by disembodying populations from landscape-level processes, thereby disconnecting species from natural selection. Tools are needed to measure the degree to which populations of large vertebrate species in formally protected and privately owned wildlife areas are self-sustaining and free to adapt. We devised a framework to measure such wildness based on 6 attributes relating to the evolutionary and ecological dynamics of vertebrates (space, disease and parasite resistance, exposure to predation, exposure to limitations and fluctuations of food and water supply, and reproduction). For each attribute, we set empirical, species-specific thresholds between 5 wildness states based on quantifiable management interventions. We analysed data from 205 private wildlife properties with management objectives spanning ecotourism to consumptive utilization to test the framework on 6 herbivore species representing a range of conservation statuses and commercial values. Wildness scores among species differed significantly, and the proportion of populations identified as wild ranged from 12% to 84%, which indicates the tool detected site-scale differences both among populations of different species and populations of the same species under different management regimes. By quantifying wildness, this framework provides practitioners with standardized measurement units that link biodiversity with the sustainable use of wildlife. Applications include informing species management plans at local scales; standardizing the inclusion of managed populations in red-list assessments; and providing a platform for certification and regulation of wildlife-based economies. Applying this framework may help embed wildness as a normative value in policy and mitigate the shifting baseline of what it means to truly conserve a species.     

Cost‐effective conservation of an endangered frog under uncertainty

How should managers choose among conservation options when resources are scarce and there is uncertainty regarding the effectiveness of actions? Well‐developed tools exist for prioritizing areas for one‐time and binary actions (e.g., protect vs. not protect), but methods for prioritizing incremental or ongoing actions (such as habitat creation and maintenance) remain uncommon. We devised an approach that combines metapopulation viability and cost‐effectiveness analyses to select among alternative conservation actions while accounting for uncertainty. In our study, cost‐effectiveness is the ratio between the benefit of an action and its economic cost, where benefit is the change in metapopulation viability. We applied the approach to the case of the endangered growling grass frog (Litoria raniformis), which is threatened by urban development. We extended a Bayesian model to predict metapopulation viability under 9 urbanization and management scenarios and incorporated the full probability distribution of possible outcomes for each scenario into the cost‐effectiveness analysis. This allowed us to discern between cost‐effective alternatives that were robust to uncertainty and those with a relatively high risk of failure. We found a relatively high risk of extinction following urbanization if the only action was reservation of core habitat; habitat creation actions performed better than enhancement actions; and cost‐effectiveness ranking changed depending on the consideration of uncertainty. Our results suggest that creation and maintenance of wetlands dedicated to L. raniformis is the only cost‐effective action likely to result in a sufficiently low risk of extinction. To our knowledge we are the first study to use Bayesian metapopulation viability analysis to explicitly incorporate parametric and demographic uncertainty into a cost‐effective evaluation of conservation actions. The approach offers guidance to decision makers aiming to achieve cost‐effective conservation under uncertainty.     

Sexual Predators,Energy Development,and Conservation in Greater Yellowstone

Abstract: In the United States, as elsewhere, a growing debate pits national energy policy and homeland security against biological conservation. In rural communities the extraction of fossil fuels is often encouraged because of the employment opportunities it offers, although the concomitant itinerant workforce is often associated with increased wildlife poaching. We explored possible positive and negative factors associated with energy extraction in the Greater Yellowstone Ecosystem (GYE), an area known for its national parks, intact biological diversity, and some of the New World's longest terrestrial migrations. Specifically, we asked whether counties with different economies—recreation (ski), agrarian (ranching or farming), and energy extractive (petroleum)—differed in healthcare (gauged by the abundance of hospital beds) and in the frequency of sexual predators. The absolute and relative frequency of registered sex offenders grew approximately two to three times faster in areas reliant on energy extraction. Healthcare among counties did not differ. The strong conflation of community dishevel, as reflected by in‐migrant sexual predators, and ecological decay in Greater Yellowstone is consistent with patterns seen in similar systems from Ecuador to northern Canada, where social and environmental disarray exist around energy boomtowns. In our case, that groups (albeit with different aims) mobilized campaigns to help maintain the quality of rural livelihoods by protecting open space is a positive sign that conservation can matter, especially in the face of rampant and poorly executed energy extraction projects. Our findings further suggest that the public and industry need stronger regulatory action to instill greater vigilance when and where social factors and land conversion impact biological systems.     

Comparison of the insecticidal effects of water extracted and intact aromatic plants onAcanthoscelides obtectus,a bruchid beetle pest of kidney beans

Summary Acanthoscelides obtectus (Say) is one of the most damaging pests of kidney beans,Phaseolus vulgaris L. worldwide. However, aromatic plants from the families Lamiaceae, Lauraceae, Myrtaceae and Poaceae can protect kidney beans by direct or delayed insecticidal effect, through increased adult mortality and inhibition of beetle reproduction (both oviposition and adult emergence). The efficiency of hydrodistillated and intact plants fromThymus vulgaris andT. serpyllum, Mentha piperata, Rosmarinus officinalis, Satureia hortensis, Eucalyptus globulus, Laurus nobilis, Origanum vulgare, andCymbopogon nardus was compared. For both extracts,Origanum vulgare had the best effect. The insecticidal effect was induced by more than the essential oils because no significant difference was noticed between distilled and intact plants extract. Inhibition of reproduction was particularly important. These results suggest that lipidic as well as non lipidic, allelochemicals, such as phenolics, or non-protein amino-acids, or flavonoids may be involved in the toxicity of aromatic plants to this beetle.