美凤蝶觅食过程中的视觉和嗅觉利用

[目的]植物的花色和花香是访花蝴蝶识别花蜜的重要信息来源,本研究旨在利用花香挥发物、蜂蜜水加花色的诱集试验探讨美凤蝶Papilio memnon视觉、嗅觉在觅食行为中的作用.[方法]测试美凤蝶对不同颜色的假花和喷施蜂蜜的假花的行为反应,采用触角电位仪(EAG)测定美凤蝶对花香挥发物的触角电位反应,并通过行为学进行验证.[结果]在无气味的7种颜色的假花诱集时,美凤蝶对蓝色(440-475 nm)、紫色(380-420 nm)和红色(615-630 nm)显示出明显的颜色趋性;在假花上喷洒蜂蜜水后,雌雄蝶总体访花次数增加1.85倍;在单一蜂蜜水、苯甲醇和苯甲醛气味诱集时,美凤蝶访问次数较少,而在气味基础上加蓝色假花诱集时,蜂蜜水诱集时美凤蝶访问次数增加了27.40倍,苯甲醇和苯甲醛诱集时美凤蝶访问次数增加了52.59倍和75.80倍.而在颜色与颜色加气味比较时,蜂蜜水诱集时美凤蝶访问次数只增加了1.41倍,苯甲醇和苯甲醛诱集时美凤蝶访问次数增加了2.67倍和2.16倍.雌雄蝶对花颜色和挥发物的敏感性均有区别,美凤蝶雌蝶对颜色和挥发物(蜂蜜水、苯甲醇和苯甲醛)的敏感性高于雄蝶(P＜0.05).[结论]颜色是美凤蝶觅食的主要因子,单一气味对美凤蝶的引诱作用有限.美凤蝶在觅食过程中,以视觉为主嗅觉为辅,雌蝶对颜色和气味的识别能力和敏感性高于雄蝶,推断可能与雌蝶在繁殖中扮演的角色相关.     

石斛篓象成虫对不同来源气味的行为反应

【目的】研究不同来源气味对石斛篓象Nassophasis sp.成虫嗅觉选择行为的影响,对于发展新型石斛篓象成虫防治技术具有重要意义。【方法】应用陷阱式嗅觉测定仪测试了石斛篓象成虫对同种个体气味、蛹壳气味、成虫粪便、球花石斛Dendrobium thyrsiflorum受害植株气味的嗅觉反应。【结果】雌成虫气味对雄成虫有引诱作用,对雌成虫没有引诱作用;雄虫气味对雌、雄成虫均无引诱效果。雌、雄蛹壳气味对雌、雄成虫均有显著引诱效果。两性成虫聚集时产生的粪便对雌、雄成虫均有显著引诱作用,雌虫或者雄虫单独放置时产生的粪便对雌、雄成虫均无引诱效果。被雌虫为害的球花石斛植株茎干释放的气味仅对雌虫有引诱作用, 而受雄虫为害后的茎干产生的气味仅对雄成虫有引诱作用。【结论】本研究为进一步分离、 鉴定对该虫有引诱作用的活性物质奠定了基础。     

斑翅果蝇求偶行为的研究

【目的】明确斑翅果蝇Drosophilasuzuki求偶行为的特征及过程、视觉因素与信息素粗提物在求偶行为中的作用。【方法】在室内条件下[温度（24±1）℃、相对湿度65%±5%,光周期14L∶10D],通过一系列的行为实验观察斑翅果蝇的求偶行为特征及过程。【结果】雄虫的求偶特征为当雌雄虫相遇前或相遇时,雌虫腹部末端翘起,雄虫转向追逐雌虫且翅膀展开;当雌虫静止时,雄虫在雌虫前方展开翅膀并伴随翅膀振动,之后雄虫绕到雌虫侧面,使用前足触碰雌虫并很快返回雌虫前方展开翅膀,随后绕到雌虫尾部弯曲腹部试图进行交配。3日龄雌虫的求偶行为次数最多,为（127.4±10.0）次,且求偶高峰期出现在进入光照期后的3-4 h时段内,为（59.2±5.4）次。与单一因素相比,未交配雌虫卵巢粗提物与死亡虫体共同作用时能够显著激发雄虫的求偶行为。进一步观察结果显示,卵巢粗提物对斑翅果蝇未交配雄虫具有显著的引诱效果,但仅有卵巢粗提物出现时并不能显著增强雄虫求偶行为。【结论】能引起斑翅果蝇雄虫求偶的化学物质（性信息素）存在斑翅果蝇雌虫卵巢中,视觉因素和性信息素联合作用才能显著增强雄虫的求偶行为。     

不同生理状态的番石榴实蝇对寄主气味的行为反应

【目的】探究番石榴果实气味对番石榴实蝇Bactroceracorrecta行为的影响,为番石榴实蝇的化学生态防治提供理论依据。【方法】利用风洞观察箱观察性未成熟、性成熟未交配和交配3种不同生理状态的番石榴实蝇雌、雄成虫对单个番石榴果实气味的定向反应,对不同生理状态的雌、雄虫的飞行速度进行了分析。【结果】番石榴果实气味对不同生理状态的番石榴实蝇雌雄成虫均能产生显著的引诱效果,交配雌虫降落到气味源的数量最多,其次是性成熟未交配的雄虫,性未成熟的雄虫降落数最少。不同生理状态下的番石榴实蝇雌雄成虫逆风飞行的速度均显著高于空白对照,性成熟的番石榴实蝇雌成虫的逆风飞行速度均高于雄成虫。【结论】不同生理状态的番石榴实蝇雌雄虫对寄主番石榴气味具有不同的敏感性和选择性,已交配雌虫反应最强,其次是性成熟未交配的雄虫,性未成熟的雄虫的反应最弱。     

大帛斑蝶成虫行为学特征

在网室内跟踪观察了大帛斑蝶Idea leuconoe成虫的活动规律。结果表明:适于大帛斑蝶羽化的温度为≥23℃,羽化主要集中在8:00—9:00,羽化当天蝴蝶极少飞行。羽化第2天开始飞行和觅食,飞行活动最早于7:30便开始有活动,最晚于18:40停止活动,阴天则会推迟开始活动时间,提前结束活动时间。雌蝶日飞行有一个高峰期,在10:00—12:00时段内最活跃,雄蝶则在10:00—12:00和14:00—16:00有2个活跃高峰期。羽化后至产卵前的8d中,大帛斑蝶雌蝶总的飞行次数、时间分别为146次和186.23 min,平均每天飞行次数为18次,飞行时间为23.28 min,单次平均飞行时间为1.28 min;雄蝶总的飞行次数、时间分别为131次和114.43 min,平均每天飞行次数16次,飞行时间为14.30 min,单次平均飞行时间为0.87 min。飞行次数和飞行时间在雌雄虫间均无显著性差异(P0.05);而雌、雄虫每天飞行规律有显著性差异(P0.05);蝴蝶种群的飞行次数与飞行时间呈显著正相关(P0.01),飞行次数和单次飞行时间也呈显著正相关(P0.01)。羽化后至产卵前大帛斑蝶雌蝶访花53次,占飞行次数的36.30%;访花时间258.87 min,超过飞行时间139.01%;平均每天访花7次,占飞行次数的38.89%;访花时间32.36 min,单次访花时间4.88 min。雄蝶访花40次,占飞行次数的30.53%;访花时间344.41 min,超过飞行时间300.98%;平均每天访花5次,占飞行次数的31.25%;访花时间43.05 min,单次访花时间8.61 min。访花次数和访花时间在雌雄虫间无显著性差异(P0.05),雌、雄虫的每天访花规律有显著差异(P0.05)。蝴蝶种群的访花次数与访花时间呈显著正相关(P0.01)。交配出现在羽化后的第6天,主要发生在12:00—16:00时段内,大部分蝴蝶交配持续时间很长,雌雄蝶均可多次交配。雌蝶最早于交配完第2天产卵,卵散产于叶背,产卵可持续2—3个月。     

青斑蝶Tirumala limniace成虫颜色偏好性研究

【目的】明确青斑蝶Tirumala limniace雌、雄成虫对颜色的偏好性,可以为此蝴蝶人工饲养时的合理环境条件设定提供必要的理论支持。【方法】本研究通过在室内和野外对青斑蝶成虫对6种颜色(白色、红色、绿色、黄色、蓝色和紫色)光源的选择行为进行观察,明确青斑蝶成虫对不同颜色的偏好性。【结果】(1)在室内和在野外雌、雄成虫均优先选择黄色。(2)雌雄成虫在野外无其它光源干扰下对黄色的选择性强于室内。(3)单色光源照明和多种不同颜色光源同时存在下,成虫对颜色的偏好程度存在差异:当只有单色光源照明时,成虫对颜色的偏好程度为黄色>绿色=红色≥蓝色≥紫色;当不同颜色光源同时存在时,成虫对颜色的偏好程度则为黄色>蓝色≥绿色=红色≥紫色。(4)在不同颜色光源同时存在时,配对后的雌成虫表现出了比雄成虫更强的颜色选择性:雌成虫对黄色光源的选择性强于雄成虫,且其未产生颜色选择的成虫数量也少于雄成虫。【结论】青斑蝶成虫存在对黄色选择的颜色恒常性,野外成虫对颜色的选择性强于室内,雌、雄成虫对偏好颜色选择性存在性别差异。     

青斑蝶成虫释放诱集研究

[目的]为营造蝴蝶飞舞的景观,本研究以青斑蝶Tirumala limniace Cramer为对象,探究了颜色和气味对该蝶觅食的引诱作用,根据引诱结果设计出一种在蝴蝶放飞后引诱蝴蝶的装置。该装置包括合适的假花颜色、引诱剂和彩灯颜色。[方法]分别测定了不同颜色和挥发性信息化合物诱集到青斑蝶的数量。[结果]视觉和嗅觉信号均对青斑蝶的觅食有引诱作用。视觉信号中,5种颜色假花引诱效果最好的是白色(9.0%),其次是黄色(3.7%)和红色(2.0%),粉红(1.7%)和紫色(1.0%)最差。3种灯光对青斑蝶的引诱效果都好于对照,其中引诱效果最好的是7色彩灯(9.3%),其次是粉红色(8.3%)和红色灯(7.0%)。嗅觉信号中,3种蜜源信息引诱剂引诱效果最好的是混合物(1%α-蒎烯+1%水杨酸甲酯+1%1-辛醛)和对照(蜂蜜水),其次是1%水杨酸甲酯,1%α-蒎烯最差。喷洒蜜源信息和蜂蜜水的红色、黄色和白色假花对青斑蝶的平均引诱率比不喷时分别提高了2.38倍、1.91倍和1.97倍,说明青斑蝶在觅食时以嗅觉信号为主,视觉信号为辅。[结论]因此,该引诱装置选择的假花颜色为白色、黄色和红色;引诱剂为1%α-蒎烯+1%水杨酸甲酯+1%1-辛醛的混合物;彩灯为7色彩灯;较好的放飞方式是分多次放飞,每次放飞蝴蝶数量200~250只。该装置制作简便,造价便宜,可重复多次使用,对蝴蝶持续引诱效果较好,适合在网室内和野外蝴蝶放飞时使用。     

异迟眼蕈蚊成虫行为学特征及性信息素初步研究

【目的】为了寻求高效无污染的防治害虫异迟眼蕈蚊Bradysia difformis Frey的方法。【方法】本文在人工气候室条件下,采用行为、化学生态学等研究方法,系统观察了异迟眼蕈蚊的羽化节律、交配行为,并对其性信息素进行了初步研究。【结果】异迟眼蕈蚊羽化没有明显的昼夜节律,雌虫在16:00—21:00达到羽化高峰,雄虫羽化高峰出现在17:00—23:00,成虫在光期的羽化数量占总羽化数量的72%。成虫的求偶交配行为多发生在羽化后10 min左右,交尾时间3 min左右。异迟眼蕈蚊雄成虫在"Y"型嗅觉仪中对雌成虫及雌成虫腹部粗提物具有正趋向行为反应(P<0.01),证明异迟眼蕈蚊雌虫释放性信息素。【结论】通过气相色谱-质谱联用仪(GC-MS)对雌、雄成虫腹部粗提物进行化学分析,得到雌成虫特有的3种化学物质:正十二烷、正十六烷酸、(Z,Z)-9,12-十八烷二烯酸,这些化合物可能是异迟眼蕈蚊雌成虫的性信息素成分。     

多次交配对小菜蛾精包形成与生殖力的影响

【目的】小菜蛾Plutella xylostella是主要为害十字花科作物的一种世界性害虫,强大的生殖能力是其成为田间最难防治的害虫的主要原因之一。交配是营两性生殖昆虫繁衍后代必要的一个生理过程,明确小菜蛾雌雄成虫的交配行为及交配后的生理响应,对于小菜蛾种群监测和综合防治具有重要意义。【方法】解剖观察小菜蛾成虫生殖腺及精包形成;利用行为学与生物学实验,测定和分析小菜蛾成虫交配与再交配能力、精包形成与消化,以及交配次数对精包形成以及雌虫生殖力的影响。【结果】小菜蛾雄成虫在交配过程中精液以精包的形式传递给雌成虫,在交配囊中精包呈白色、不透明、气球状结构,交配结束后精包可被充分消化和吸收。成虫交配能力观测结果显示,小菜蛾雌雄成虫均具有多次交配行为。首次交配后,雄成虫表现出短暂的再交配延迟,20 min内其交配成功率为54.6%,显著低于首次交配。虽然交配次数不会影响雄成虫的交配时长,但雄成虫交配史对其自身的精包大小以及雌成虫的生殖力均具有显著的抑制作用。雌成虫表现出明显的再交配抑制性,交配过的雌成虫在12 h内的交配率显著低于未交配雌成虫的,这可能取决于首次交配后精包的消化和吸收速率。雌成虫多次交配后,其产卵量和卵孵化率与单次交配的相比没有显著差异。【结论】多次交配会使小菜蛾雄成虫再交配延迟,雌成虫再交配受到抑制;多次交配产生的雄成虫精包显著减小,雌成虫产卵量与卵孵化率并没有从多次交配中获得收益。本研究为解析小菜蛾雌雄成虫生殖调控机制奠定理论基础。     

异色瓢虫气味结合蛋白基因HaxyOBP1和HaxyOBP6的克隆及表达谱分析

【目的】本研究旨在探索异色瓢虫Harmonia axyridis气味结合蛋白的结构和分布,更好地了解气味结合蛋白在异色瓢虫嗅觉系统中的作用。【方法】利用生物信息学方法克隆异色瓢虫2个气味结合蛋白基因序列并对其蛋白结构进行分析;通过实时荧光定量PCR分析克隆获得的这2个基因在异色瓢虫各个发育阶段和成虫不同组织中的表达水平。【结果】本研究成功克隆得到异色瓢虫两个气味结合蛋白基因HaxyOBP1和HaxyOBP6(GenBank登录号分别为MG757923和MG757927)。HaxyOBP1开放阅读框全长447 bp,编码148个氨基酸,具有6个保守的半胱氨酸,表明HaxyOBP1属于Classic OBPs。HaxyOBP1在异色瓢虫各发育阶段均有表达,在雄性成虫中表达量最高;组织表达谱分析表明HaxyOBP1在雄虫头部表达量最高。HaxyOBP6开放阅读框全长414 bp,编码137个氨基酸,具有4个保守的半胱氨酸,表明HaxyOBP6属于Minus-C OBPs。HaxyOBP6在成虫期的表达量明显高于幼虫阶段,并且在雄成虫中的表达量显著高于雌成虫;组织表达谱分析表明HaxyOBP6在雄成虫头部和雌成虫翅中表达量最高。【结论】本研究克隆得到异色瓢虫两个气味结合蛋白基因,表达谱分析表明HaxyOBP1和HaxyOBP6分别在异色瓢虫成虫头和翅中具有较高的表达水平,说明气味结合蛋白基因可能在异色瓢虫非嗅觉组织中同样具有重要作用。本研究结果为深入研究异色瓢虫气味结合蛋白结构和功能奠定了基础。     

Visual and Olfactory Responses of Seven Butterfly Species During Foraging

Foraging responses of seven butterfly species were determined for flower models that differed in color, size, and depth of artificial corolla. We measured frequency of visits to flowers of various colors (red, orange, yellow, purple, and white) with or without the application of honey water to flower models. We found that the relative strength of butterfly response to visual versus olfactory cues differed among butterfly species. We suggest that the seven butterfly species tested exhibit four different patterns in how visual and olfactory cues were combined as determinants of foraging importance: (1) vision was given priority over olfaction (in Cethosia cyane and Danaus chrysippus); (2) olfaction was given priority over vision (Cethosia biblis, Idea leuconoe, and Tirumala limniace); (3) olfaction and vision were equally important (Catopsilia pomona); and (4) only olfaction was used (e.g., Danaus genutia, which was not sensitive to the five colors tested but very sensitive to the smell of honey in our experiments). In tests with flower models of different sizes, the visitation frequency of C. cyane, I. leuconoe, and D. chrysippus increased with increasing corolla diameter, provided flowers were sprayed with honey water. C. cyane and D. chrysippus showed this trend because of their strong dependence on visual cues. In contrast, I. leuconoe with its large body size preferred larger flowers, it could be that butterflies need more nectar to support its large body size. Catopsilia pomona tended to visit large and middle-sized flowers because it used both vision and odor to detect food, large or middle-sized flowers could have more vision and odor stimulation than small flowers for foraging butterfly. The other three butterfly species did not show that trend because of lack of dependence on visual cues. There was no correlation between visitation frequency and corolla depth within particular butterfly species. In conclusion, the foraging strategies of butterflies are not only mainly determined by the weights given to visual and olfactory cues, but also affected by body size.     

西方蜜蜂和兰州熊蜂在设施桃园的访花偏好性比较

【目的】为了比较西方蜜蜂 Apis mellifera 和兰州熊蜂 Bombus lantschouensis 在设施桃园内对不同时期桃花的访花偏好性、以及这种偏好性与花粉活力和采集花粉花蜜之间的关系。【方法】记录2种蜂在温室桃园内访问早期花、中期花和晚期花的比例,测定桃花不同时期的花粉活力以及2种蜂携带的花粉活力,观察2种蜂采集花蜜和采集花粉的成功率,统计2种蜂访花过程中桃花所处的枝条数及植株数。【结果】桃花不同时期的花粉活力差异显著,早期花花药未开裂,花粉未释放,中期花花粉活力（58.3%）显著高于晚期花花粉活力（34.2%）（P<0.01）;西方蜜蜂更加偏好访问中期花,对中期花的访问率高达75.3%,显著高于兰州熊蜂对中期花的访问率（49.2%）（P<0.01）;西方蜜蜂携带的花粉活力（92.1%）显著高于兰州熊蜂携带的花粉活力（72.9%）,但是西方蜜蜂采集花粉和采集花蜜的成功率均低于兰州熊蜂（P<0.01）;在访问一定数量的桃花过程中,兰州熊蜂在设施桃园内访问的枝条数和植株数较多,分布范围较广（P<0.01）。【结论】和兰州熊蜂相比,西方蜜蜂对活力花粉的辨别能力更强,更加偏好访问花粉活力较高的花朵,这种偏好性导致其采集花粉花蜜的成功率降低。     

意大利蜜蜂对两种油菜花朵气味的偏爱性

【目的】明确意大利蜜蜂Apis mellifera ligustica（简称“意蜂”）对两种油菜（甘蓝型胜利油菜 Brassica napus cv. Shengli和芥菜型马尾油菜 B. juncea cv. Mawei）的气味偏爱性及选择行为特征。【方法】本研究开展大田访花偏爱性试验、室外群体气味偏爱性试验以及室内“Y”型嗅觉仪行为反应和学习记忆试验,测定意蜂蜂群及青年采集蜂对甘蓝型胜利油菜和芥菜型马尾油菜两种油菜花朵的选择次数,并通过采集蜂训练时及训练后的喙伸反应率分析两种油菜花朵气味对采集蜂学习记忆能力的影响,最终评估意蜂蜂群及个体对这两种油茶花朵气味的选择性。【结果】大田试验12:00-13:00时间段,访问胜利油菜的意蜂数量显著高于访问马尾油菜的数量(P<0.05）。群体气味偏爱性试验14:00-15:00时间段意蜂访问胜利油菜的数量显著高于访问马尾油菜的数量（P<0.05）。行为反应试验结果显示意蜂选择胜利油菜的次数（3.86±2.83）显著高于访问马尾油菜的次数（2.28±1.87）（P<0.05）。在学习记忆试验中,随着训练次数的增加,意蜂对两种油菜花朵气味的喙伸反应率逐渐升高,相同的训练次数,意蜂对两种油菜气味的学习能力差异不显著（P>0.05）;训练结束后,随着时间的增加,意蜂对胜利油菜及马尾油菜的气味记忆逐渐下降,在24 h对胜利油菜的气味记忆明显高于对马尾油菜的气味记忆（P<0.05）。【结论】本研究证明意蜂较偏爱胜利油菜的花朵气味,花朵气味是影响其采集偏爱的重要因素,气味响应性试验可定量分析蜜蜂对花朵气味的嗅觉敏感性。     

Butterfly species diversity and their floral preferences in the Rupa Wetland of Nepal

Floral attributes often influence the foraging choices of nectar‐feeding butterflies, given the close association between plants and these butterfly pollinators. The diversity of butterflies is known to a large extent in Nepal, but little information is available on the feeding habits of butterflies. This study was conducted along the periphery of Rupa Wetland from January to December 2019 to assess butterfly species diversity and to identify the factors influencing their foraging choices. In total, we recorded 1535 individuals of 138 species representing all six families. For our examination of butterfly–nectar plant interactions, we recorded a total of 298 individuals belonging to 31 species of butterfly visiting a total of 28 nectar plant species. Overall, total butterfly visitation was found to be significantly influenced by plant category (herbaceous preferred over woody), floral color (yellow white and purple preferred over pink), and corolla type (tubular preferred over nontubular). Moreover, there was a significant positive correlation between the proboscis length of butterflies and the corolla tube length of flowers. Examining each butterfly family separately revealed that, for four of the families (Lycaenidae, Nymphalidae, Papilionidae, and Pieridae), none of the tested factors (flower color, plant category, and corolla type) were shown to significantly influence butterfly abundance at flowers. However, Hesperidae abundance was found to be significantly influenced by both flower color (with more butterflies observed at yellow flowers than purple) and flower type (with more butterflies observed at tubular flowers than nontubular flowers). Our results reveal that Rupa Lake is a suitable habitat for butterflies, providing valuable floral resources. Hence, further detailed studies encompassing all seasons, a greater variety of plants, and other influential factors in different ecological regions are fundamental for creating favorable environments to sustain important butterfly pollinators and help create balanced wetland ecosystems.     

韭菜迟眼蕈蚊成虫行为活动昼夜节律

【目的】本研究旨在明确韭菜迟眼蕈蚊Bradysia cellarum成虫行为活动的昼夜节律,为其室内饲养、行为学研究和研发精准、高效的监测与防控新技术提供依据。【方法】室内系统观察记录了韭菜迟眼蕈蚊成虫羽化盛期求偶、交配、产卵、移动与静息等行为的昼夜节律,分析了其特定行为的时间分配特征。【结果】韭菜迟眼蕈蚊成虫的运动行为和静息行为白天和黑夜均有发生,夜间的繁殖行为(求偶、交配和产卵)频次高于白天的,各时间点的移动、静息和繁殖行为频次占比间均具有显著性差异。韭菜迟眼蕈蚊雌雄成虫的求偶节律相同,一天中求偶有两次高峰,分别出现在3:00和7:00。韭菜迟眼蕈蚊雌雄成虫的交配节律与雌成虫的产卵节律相似,雄成虫移动行为频次占比的峰值时刻均出现在3:00时,雌成虫移动行为频次占比的峰值时刻则出现在19:00时。雌雄成虫静息行为的频次占比均无明显昼夜节律高峰。在日时间分配上,雌、雄成虫以静息行为的时间占比最多,分别为89.53%和89.90%;求偶行为的时间占比最少,分别为0.56%和0.89%。雌雄成虫各行为的日时间占比差异不显著。【结论】韭菜迟眼蕈蚊成虫的求偶、交配、产卵、移动和静息行为具有明显...     

Reversal Learning and Risk‐Averse Foraging Behavior in the Monarch Butterfly,Danaus plexippus (Lepidoptera: Nymphalidae)

Learning ability allows insects to respond to a variable environment, and to adjust their behaviors in response to positive or negative experiences. Pollinating insects readily learn to associate floral characteristics, such as color, shape, or pattern, with appetitive stimuli, such as the presence of a nectar reward. However, in nature pollinators may also encounter flowers that contain distasteful or toxic nectar, or offer highly variable nectar volumes, providing opportunities for aversive learning or risk‐averse foraging behavior. Whereas some bees learn to avoid flowers with unpalatable or unreliable nectar rewards, little is known about how Lepidoptera respond to such stimuli. We used a reversal learning paradigm to establish that monarch butterflies learn to discriminate against colored artificial flowers that contain salt solution, decreasing both number of probes and probing time on flowers of a preferred color and altogether avoiding artificial flowers of a non‐preferred color. In addition, when we offered butterflies artificial flowers of two different colors, both of which contained the same mean nectar volume but which differed in variance, the monarchs exhibited risk‐averse foraging: they probed the constant flowers significantly more than the variable ones, regardless of flower color or butterfly sex. Our results add to our understanding of butterfly foraging behavior, as they demonstrate that monarchs can respond to aversive as well as appetitive stimuli, and can also adjust their foraging behavior to avoid floral resources with high variance rewards.     

海切叶蜂的筑巢和访花行为

【目的】研究毛乌素沙地重要野生传粉昆虫海切叶蜂Megachile maritima的筑巢和访花行为对保护其栖息环境具有重要意义。【方法】采用目测及拍照等方法对海切叶蜂的整个筑巢过程进行了连续观测;以2 m×2 m 样方的方式观测海切叶蜂的访花频率、单花停留时间及日活动规律等访花行为,其中日活动规律每天连续观测,共观测7天。【结果】海切叶蜂在沙土中筑巢,每巢只有一个巢室,其筑巢过程为：寻找合适的筑巢地点,挖巢,构建巢室,采集蜂粮,产卵,封住巢室,筑完一个巢。它连续筑完一个巢大约需要9 h。海切叶蜂构建一个巢室需要切取26～29片叶子,为每巢室采集蜂粮11～12次,每巢室内产卵1粒;在塔落岩黄芪和细叶益母草上的平均访花频率分别为（13.23±6.49）朵/min和（16.72±4.84）朵/min,平均单花停留时间分别为（3.08±2.48）s和（2.49±1.31）s。晴天,海切叶蜂在12:00～14:00期间活动较活跃。【结论】海切叶蜂不同个体之间的筑巢行为相似。该蜂在塔落岩黄芪和细叶益母草上的访花过程、访花频率及单花停留时间具有显著的差异。     

First Quantification of Courtship Behavior in a Silver Fly,Leucopis palumbii (Diptera: Chamaemyiidae): Role of Visual,Olfactory and Tactile Cues

Research on the courtship and mating behavior of insects is the first step toward a full understanding of their behavioral ecology. Investigating mating behavioral sequences could help to unravel mate assessment and mate choice dynamics in entomophagous organisms, adding useful information to develop behavior-based control strategies. In this research, courtship and mating displays, magnitude of male-male sexual interactions and role of female-borne cues evoking male courtship were analyzed in Leucopis palumbii Rondani (Diptera: Chamaemyiidae), a larval predator of aphids. Courtship was initiated by the male and was characterized by three main steps: chasing of the female, wing fanning in her close proximity and tarsal tapping with forelegs on the female’s body. Copulation may follow lasting 765?±?211.25 s. Same-sex interactions among males (i.e. wing fanning followed by tarsal tapping) were also registered. Male fanning before a successful courtship differed from fanning performed prior to an unsuccessful approach in terms of mean frequency. Female-borne stimuli played a key role in eliciting courtship responses from males. The best male’s response was achieved when physical and chemical cues arising from the female body were contemporarily provided, allowing synergistic visual, olfactory and tactile perception. Results contribute to understanding the role of visual, olfactory and tactile channels among sensory modalities used by aphidophagous Chamaemyiidae during sexual communication.     

Flower choice by honey bees (Apis mellifera L.): sex-phase of flowers and preferences among nectar and pollen foragers

Bees foraging for nectar should choose different inflorescences from those foraging for both pollen and nectar, if inflorescences consist of differing proportions of male and female flowers, particularly if the sex phases of the flowers differ in nectar content as well as the occurrence of pollen. This study tested this prediction using worker honey bees (Apis mellifera L.) foraging on inflorescences of Lavandula stoechas. Female flowers contained about twice the volume of nectar of male flowers. As one would predict, bees foraging for nectar only chose inflorescences with disproportionately more female flowers: time spent on the inflorescence was correlated with the number of female flowers, but not with the number of male flowers. Inflorescence size was inversely correlated with the number of female flowers, and could be used as a morphological cue by these bees. Also as predicted, workers foraging for both pollen and nectar chose inflorescences with relatively greater numbers of both male and female flowers: time spent on these inflorescences was correlated with the number of male flowers, but not with the number of females flowers. A morphological cue inversely associated with such inflorescences is the size of the bract display. Choice of flowers within inflorescences was also influenced predictably, but preferences appeared to be based upon corolla size rather than directly on sex phase.