珍贵绢丝昆虫——天蚕蚕蛾翅振行为观察

本文较系统地观察和测定了天蚕蚕蛾的翅振时间节律和翅振频率。结果表明,雄蚕蛾不论独处还是与雌蚕蛾共存,其翅振行为均出现于18：00至次日6：00之间,其中以22：00至次日4：00为主;雌蚕蛾独处时未见翅振行为,只有与雄蛾共存时方有此行为,出现于22：00至次日6：00。雌雄蚕蛾翅振行为参数,包括日翅振次数、翅振总时间、一次翅振持续时间、两次翅振间间隔时间等,因蚕蛾日龄和存在方式(独处或与异性共存)而异;雌雄蚕蛾相比,除两次翅振间隔时间外,雄蛾均明显高些。雌雄蚕蛾翅振频率一般为7-12Hz,不同日龄闯,雄蛾以羽化第2天为高,平均10.9741Hz;雌蛾以羽化第1天为高,平均10．7071Hz。同一日龄不同时刻间翅振频率有一定差异,但未达显著水平。此外,尚观察了雄蛾触角对其翅振行为表现的作用,最后讨论了制种中拟注意的有关问题。     

快速分离蚊虫雌雄蛹的分离器

<正> 昆虫不育雄虫释放技术是害虫防治中的一门新兴技术。该技术在蚊虫的防治中已有较多的研究。在大规模释放计划中,要将雄蛹从大量蛹群中检出,以便对雄蛹或雌性成蚊作必要的不育处理。不言而喻,雌蛹或雌蚊在蚊群中     

淡色库蚊的飞翔声

用声音传递倩息是昆虫种内通讯的一种方式。自声学技术引进以来,研究昆虫鸣声的特点和行为效应已有较快的进展。不同类型的昆虫发声方式不同,双翅目昆虫是靠翅的振动来发声的。根据文献记载,不同蚊种飞翔声的基音频率不同,同种蚊虫雌雄两性飞翔声的基音频率也有明显的差别。最近,Belton等(1979)对加拿大西部13种雌蚊的飞翔声作了比较,并对尖音库蚊C.pipiens作了较详细的分析,但没有分沂该种雄蚊飞翔声的频谱特性。此外,前人的研究结果表明,尖音库蚊,埃及伊蚊等许多种类雌蚊的飞翔声能引诱雄蚊(Clements,1963;Wishart,1959)。而雄蚊飞翔声能否对雌蚊发生作用,至今尚属疑问。     

褐飞虱求偶鸣声中有效声段及其特征

对褐飞虱Nilaparvata lugens (Stal) 雌、雄虫播放求偶鸣声信号的不同声段及其组合,结果表明在它们求偶识别过程中,由多个规则连续的声脉冲所组成的声段是有效的。播放不同声脉冲重复频率和主振频率组合的模拟信号,表明褐飞虱雌、雄虫求偶信号的声脉冲重复频率是它们识别异性的敏感声学特征参数,其敏感范围较窄,分别为70～90 Hz和22 Hz左右;而对主振频率的敏感范围较宽,分别为200 ～1 700 Hz和100～300 Hz。     

噻派对淡色库蚊的不育作用

本文报道了昆虫化学不育剂噻派(Thiotepa)对淡色库蚊(Culex pipiens pallens Coq.)的不育作用,以及对雄蚊交配竞争力和副腺的影响。试验证明用噻派处理雄蛹,浓度范围在0.5—0.8%,处理时间为1—3小时,其不育率可达90%以上。0.7%浓度的噻派处理雄蛹1小时,不育雄蚊的交配竞争力胜过正常雄蚊。经用遗传标记蚊虫测试,表明雄蚊副腺未发生损伤,与其交配的雌蚊仍保持单配性。     

褐飞虱的迁人和翅型分化规律的研究

褐飞虱Nilaparvata lugens(Stal)属迁飞性水稻害虫,其成虫有短翅和长翅两种翅型。 褐飞虱迁入雌虫均未经过交配,其短翅型由一对显性等位基因控制。翅型分化同时受到遗传和内分泌系统的协调控制,外界条件如密度和寄主等因子通过内分泌系统来影响翅型的分化。褐飞虱翅型分化的敏感龄期雌虫为1～3龄,而雄虫为1-5龄;不同若虫蜜度处理对褐飞虱成虫的前翅形成有一定的影响。分蘖期水稻饲养的褐飞虱短翅型比例明显高于孕穗期水稻饲养的褐飞虱。不同密度下各生物型间的翅型分化差异不显著。迁入地的浙江各种群属温带型,其雌虫短翅率低且与密度呈显著负相关;菲律宾热带种群雌虫在不同密度下均为短翅型,而雄虫的短翅率随密度增加而上升。广西种群接近热带型,其雌虫短翅率高但不随密度而变化。试验各种群的雄虫在中等密度甚至高密度时其短翅率出现最高。     

垂叶榕果内寄生瘿蚊的发生规律

在云南西双版纳热带地区,一种还未被描述属和种的瘿蚊寄生于垂叶榕果内的雌花子房里,并膨大形成虫瘿,靠取食花胚组织完成发育.通过2010年定时定点的系统观察和研究瘿蚊的发生规律,结果发现:该种瘿蚊在垂叶榕上发生频率较高,抽样的18批果有17批被瘿蚊寄生,其中有13批果的寄生比率超过了60％,部分甚至达到100％.瘿蚊寄生雌花的平均比率不超过6％,平均每个榕果内有瘿蚊1～40只不等.瘿蚊寄生不仅降低了垂叶榕的种子数,还致命性地影响着传粉榕小蜂的繁殖.在对瘿蚊的羽化、交配行为及其成虫的活动规律观察中,结果显示:寄生在一个榕果里瘿蚊需要5～7d才能羽化完,其羽化高峰期出现在第2～3天;一天内羽化的高峰出现在上午8:00-10:00及晚上20:00-0:00;而羽化后瘿蚊活动高峰期出现在上午8:00-11:00.雄蚊会帮助雌蚊离开榕果并优先获得交配权,雌蚊交配后飞离繁殖自身的榕树,去寻找适合产卵的榕果繁殖后代,雄蚊不离开羽化树,而死在繁殖自身的榕树附近.这些结果为深入研究瘿蚊的防治技术提供了科学依据.     

褐飞虱五龄若虫翅芽长度与成虫翅型关系的研究

褐飞虱饲养于不同水稻品种、不同生育期以及不同种群密度条件下,5龄若虫翅芽长度与成虫翅型具有稳定的相关性：翅芽长于1．10mm羽化后为长翅型雌虫,介于0．96～1．09mm之间为长翅型雄虫或短翅型雌虫,小于0．95mm为短翅型雄虫。根据5龄若虫翅芽长度结合外生殖器特征,编制了成虫翅型检索表。由此,可在5龄若虫期预测成虫的翅型和种群盛衰的趋势。     

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。     

海南岛发现的一种新种库蚊——琼中库蚊

1960年4月作者在海南岛工作时,曾捞获库蚊幼虫数条,其中一部分经饲养羽化分别得雌蚊2个,雄蚊3个,现经鉴定证明系一新种。兹将其形态描述于下: 琼中库蚊 Culex(Lophoceratomyia)chiungchungensis新种 一、成虫 小形棕黑色品种。翅长雄蚊约2.5毫米;雌蚊约3毫米。 雌性——头 顶部被以黑色竖立窄鳞,前部及二侧眼缘有白色扁平鳞片着生。头部的鬃均为黑色。触角、触须及喙均为黑色;触须长约喙的1/8。     

The auditory system of blood-sucking mosquito females (Diptera, Culicidae): Acoustic perception during flight simulation

Mosquitoes hear with their plumose antennae which respond to the air movement caused by sound propagation and conduct vibrations to the Johnston’s organ located at the base of each antenna. Each of the two Johnston’s organs contains several tens of thousands mechanosensory cells which detect the displacements of the flagellum and transform them into electric potentials. Hearing plays a very important role in the reproductive behavior of the male mosquitoes. At the same time, our knowledge of hearing in female mosquitoes is very limited and its functional significance is obscure. In this study we measured the auditory sensitivity of female mosquitoes and investigated how the flight conditions affect their hearing. We studied mosquitoes of three species: Anopheles messeae, Aedes excrucians, and Culex pipiens pipiens. The neuronal responses were recorded with a glass microelectrode from the antennal nerve and the deutocerebral interneurons. Stimulation was applied in two modes: (1) the main stimulus against the background of flight simulation (strong vibration with the typical wingbeat frequency of a given mosquito species) and (2) only the main stimulus without the background stimulation. During the flight simulation, females demonstrated an increased sensitivity to frequencies below 200 Hz. The mean auditory receptor threshold at 80–120 Hz was 45 dB, which was 8 dB lower than that without flight simulation. An additional zone of increased sensitivity was also found at frequencies higher than the simulated wingbeat frequency (the so-called image channel). Our analysis of frequency tuning curves measured from the receptors and auditory interneurons shows that mosquito auditory neuronal complex consists of several subsystems which have different frequency tuning parameters, and suggests the possibility of spectral analysis of sounds. Three hypotheses could be proposed on the function of hearing in female mosquitoes: (1) predator avoidance, (2) detection of moving prey, and (3) intraspecific communication. Each of the hypotheses involves the ability to analyze the sound frequency spectrum and subsequent signal recognition.     

Nanometre-range acoustic sensitivity in male and female mosquitoes

Johnston's sensory organ at the base of the antenna serves as a movement sound detector in male mosquitoes, sensing antennal vibrations induced by the flight sounds of conspecific females. Simultaneous examination of acoustically elicited antennal vibrations and neural responses in the mosquito species Toxorhynchites brevipalpis has now demonstrated the exquisite acoustic and mechanical sensitivity of Johnston's organ in males and, surprisingly, also in females. The female Johnston's organ is less sensitive than that of males. Yet it responds to antennal deflections of +/- 0.0005 degrees induced by +/- 11 nm air particle displacements in the sound field, thereby surpassing the other insect movement sound detectors in sensitivity. These findings strongly suggest that the reception of sounds plays a crucial role in the sensory ecology of both mosquito sexes.     

Courtship Sounds Advertise Species Identity and Male Quality in Sympatric Pomatoschistus spp. Gobies

Acoustic signals can encode crucial information about species identity and individual quality. We recorded and compared male courtship drum sounds of the sand goby Pomatoschistus minutus and the painted goby P. pictus and examined if they can function in species recognition within sympatric populations. We also examined which acoustic features are related to male quality and the factors that affect female courtship in the sand goby, to determine whether vocalisations potentially play a role in mate assessment. Drums produced by the painted goby showed significantly higher dominant frequencies, higher sound pulse repetition rates and longer intervals between sounds than those of the sand goby. In the sand goby, male quality was predicted by visual and acoustic courtship signals. Regression analyses showed that sound amplitude was a good predictor of male length, whereas the duration of nest behaviour and active calling rate (i.e. excluding silent periods) were good predictors of male condition factor and fat reserves respectively. In addition, the level of female courtship was predicted by male nest behaviour. The results suggest that the frequency and temporal patterns of sounds can encode species identity, whereas sound amplitude and calling activity reflects male size and fat reserves. Visual courtship duration (nest-related behaviour) also seems relevant to mate choice, since it reflects male condition and is related to female courtship. Our work suggests that acoustic communication can contribute to mate choice in the sand goby group, and invites further study.     

Low-Frequency Sounds Repel Male Mosquitoes <Emphasis Type="Italic">Aedes diantaeus</Emphasis> N.D.K. (Diptera,Culicidae)

We experimentally demonstrated that tonal acoustic signals with a carrier frequency of 140–200 Hz had a repellent effect on male mosquitoes (Culicidae). Swarming males of Aedes diantaeus were concentrated in a small space near the auxiliary attracting sound source which simulated the flight sound of conspecific females (carrier frequency 280–320 Hz). Then, the resulting cluster of attracted mosquitoes was stimulated with test signals of variable amplitude and carrier frequency from a second loudspeaker. The direction of mosquito flight from the source of test sounds and a decrease in their number above the attracting sound source were used as the criteria of behavioral response. Pronounced avoidance responses (negative phonotaxis) of swarming mosquitoes were observed in the range of 140–200 Hz. Most of the mosquitoes left the area above the attracting sound source within one second after the onset of the test signal. Mosquitoes mostly flew up, sideways, and backwards in relation to the test acoustic vector. We presume that mosquitoes develop defensive behavior against attacking predatory insects based on analysis of auditory information. The range of negative phonotaxis is limited at higher frequencies by the spectrum of the flight sounds of conspecific females, and in the low frequency range, by the increasing level of atmospheric noise.     

Stridulatory Sound-Production and Its Function in Females of the Cicada Subpsaltria yangi

Acoustic behavior plays a crucial role in many aspects of cicada biology, such as reproduction and intrasexual competition. Although female sound production has been reported in some cicada species, acoustic behavior of female cicadas has received little attention. In cicada Subpsaltria yangi, the females possess a pair of unusually well-developed stridulatory organs. Here, sound production and its function in females of this remarkable cicada species were investigated. We revealed that the females could produce sounds by stridulatory mechanism during pair formation, and the sounds were able to elicit both acoustic and phonotactic responses from males. In addition, the forewings would strike the body during performing stridulatory sound-producing movements, which generated impact sounds. Acoustic playback experiments indicated that the impact sounds played no role in the behavioral context of pair formation. This study provides the first experimental evidence that females of a cicada species can generate sounds by stridulatory mechanism. We anticipate that our results will promote acoustic studies on females of other cicada species which also possess stridulatory system.     

Discrimination of wingbeat motion by bats,correlated with echolocation sound pattern

Summary Bats of the species Rhinolophus rouxi, Hipposideros lankadiva and Eptesicus fuscus were trained to discriminate between two simultaneously presented artificial insect wingbeat targets moving at different wingbeat rates. During the discrimination trials, R. rouxi, H. lankadiva and E. fuscus emitted long-CF/FM, short-CF/FM and FM echolocation sounds respectively. R. rouxi, H. lankadiva and E. fuscus were able to discriminate a difference in wingbeat rate of 2.7 Hz, 9.2 Hz and 15.8 Hz, respectively, between two simultaneously presented targets at an absolute wingbeat rate of 60 Hz, using a criterion of 75% correct responses.The performance of the different bat species is correlated with the echolocation signal design used by each species, particularly with the presence and relative duration of a narrowband component preceding a broadband FM component. These results provide behavioral evidence supporting the hypothesis that bats that use CF/FM echolocation sounds have adaptations for the perception of insect wingbeat motion and that long-CF/FM species are more specialized for this task than short-CF/FM species.Abbreviations CF constant frequency - FM frequency modulation     

Acoustic irradiation produced by flying moths (Lepidoptera,Noctuidae)

Characteristics of acoustic waves accompanying the flight of noctuid moths (Noctuidae) were measured. The low-frequency part of the spectrum is formed of a series of up to 17 harmonics of the wingbeat frequency (30–50 Hz) with a general tendency toward the decrease in the spectral density and the increase in the sound frequency. The root-mean-square level of the sound pressure from flapping wings was found to be 70–78 dB SPL. Besides low-frequency components, the flight of moths was accompanied by short ultrasonic pulses, which appeared with every wingbeat. Most of the spectral energy was concentrated within a range of 7–150 kHz with the main peaks at 60–110 kHz. The short-term pulses were divided into two or more subpulses with different spectra. The high-frequency pulses were produced at two phases of the wingbeat cycle: during the pronation of the wings at the highest point and at the beginning of their upward movement from the lowest point. In most of the specimens tested, the peak amplitude of sounds varied from 55 to 65 dB SPL at a distance of 6 cm from the insect body. However, in nine noctuid species, no high-frequency acoustic components were recorded. In these experiments, the acoustic flow from the flying moth within a frequency range of 2 to 20 kHz did not exceed the self-noise level of the microphone amplifier (RMS 18 dB SPL). Probable mechanisms of the high frequency acoustic emission during flight, the effect of these sounds on the auditory sensitivity of moths, and the possibility of their self-revealing to insectivorous bats are discussed. In addition, spectral characteristics of the moth echolocation clicks were more precisely determined within the higher frequency range (>100 kHz).     

Vibration and sound communication in solitary bees and wasps

ABSTRACT. Females of solitary bees ( Colletes cunicularius L.) and of digger wasps ( Bembix rostrata L.) produce buzzing sounds and are known to secrete volatile odours when digging their way from the subterranean nests to the soil surface. The odours allow patrolling males to determine the approximate position of the digging virgin female. The buzzes are measured as substrate-borne sound (soil buzz vibrations) and as air-borne sound (soil buzz sounds). Play-back experiments suggest that the soil buzzes are used by the males as additional cues for localization. Faint buzz sounds are emitted regularly by the male during genital contact in copulation. They may serve to change the receptivity of the female. Intense and broadband buzz sounds are produced by bees of either sex, if restrained from moving, perhaps serving to deter predators.     

Modulation of auditory responsiveness in the locust

The auditory responsiveness of a number of neurones in the meso- and metathoracic ganglia of the locust, Locusta migratoria, was found to change systematically during concomitant wind stimulation. Changes in responsiveness were of three kinds: a suppression of the response to low frequency sound (5 kHz), but an unchanged or increased response to high frequency (12 kHz) sound; an increased response to all sound; a decrease in the excitatory, and an increase in the inhibitory, components of a response to sound. Suppression of the response to low frequency sound was mediated by wind, rather than by the flight motor. Wind stimulation caused an increase in membrane conductance and concomitant depolarization in recorded neurones. Wind stimulation potentiated the spike response to a given depolarizing current, and the spike response to a high frequency sound, by about the same amount. The strongest wind-related input to interneuron 714 was via the metathoracic N6, which carries the axons of auditory receptors from the ear. The EPSP evoked in central neurones by electrical stimulation of metathoracic N6 was suppressed by wind stimulation, and by low frequency (5 kHz), but not high frequency (10 kHz), sound. This suppression disappeared when N6 was cut distally to the stimulating electrodes. Responses to low frequency (5 kHz), rather than high frequency (12 kHz), sounds could be suppressed by a second low frequency tone with an intensity above 50-55 dB SPL for a 5 kHz suppressing tone. Suppression of the electrically-evoked EPSP in neurone 714 was greatest at those sound frequencies represented maximally in the spectrum of the locust's wingbeat. It is concluded that the acoustic components of a wind stimulus are able to mediate both inhibition and excitation in the auditory pathway. By suppressing the responses to low frequency sounds, wind stimulation would effectively shift the frequency-response characteristics of central auditory neurones during flight.