小地老虎的交配行为和能力

在温度为(25±1)℃、相对湿度为70%±7%、光周期(L∶D)为14∶10h的条件下对小地老虎Agrotis ypsilon(Rottemberg)的交配行为和能力进行研究。结果表明:成虫在羽化后1d才进行交配。雄蛾和雌蛾都可以多次交配。交配能力受性比的影响很大,当1头雄蛾仅与1头雌蛾相处时,其交配能力低;当1头雄蛾与多于2头的雌蛾在一起时或1头雌蛾与多于2头的雄蛾在一起时,交配能力则显著增加。还讨论了该研究结果应用的可能性。     

Mating frequency and reproductive success in an income breeding moth,Mnesampela privata

The frequency of mating in insects is often an important determinant of female reproductive output and male sperm competition. In Lepidoptera that provide male nutrients to the female when mating, it is hypothesized that polyandry may be more prevalent. This is thought to be especially so among species described as income breeders; that is, in species who do not derive all their nutrients for reproductive output entirely from the resources obtained during the larval stage. We selected the geometrid moth, Mnesampela privata (Guenée) (Lepidoptera: Geometridae), to examine this hypothesis further. We found this species was best characterized as an income breeder with female weight on emergence positively correlated with total egg load but not with the number of eggs laid. Further, in accord with income breeders, females emerged with a partially developed egg load and lifetime fecundity was positively correlated with the number of oviposition days. However, in the laboratory we found that incidence of repeated matings or polyandry was rare. When moths were paired singly over their lifetime, only 4% of mated females multiple mated. When females were paired with three males concurrently, female mating success increased from 60 to 81% with multiple mating among mated females increasing to just 15%. Dissection of wild caught M. privata found that polyandry levels were also low with a maximum of 16.4% of females collected at any one time being multiple mated. In accord with theory, mating significantly increased the longevity of females, but not of males, suggesting that females acquire essential resources from male ejaculates. Despite this, multiple mated females showed a trend toward decreasing rather than increasing female reproductive output. Spermatophore size, measured on death of the female, was not correlated with male or female forewing length but was negatively correlated with the number of fertile eggs laid and female longevity. Smaller spermatophore width may be related to uptake of more nutrients by the female from a spermatophore. We discuss our findings in relation to income breeding and its relationship to polyandry in Lepidoptera.     

Female pheromonal chorusing in an arctiid moth, Utetheisa ornatrix

We report an unusual case of communal sexual display in thearctiid moth Utetheisa ornatrix that we designate "female pheromonalchorusing." As in most moths, female U. ornatrix release a long-distancesexual advertisement pheromone during a nightly activity period.We arranged U. ornatrix females in 2 types of signaling conditions:grouped and solitary. When the females were grouped with neighboringsignaling females (grouped), they initiated pheromone releasesooner, continued release with less interruption and over alonger total period, and performed the release with faster abdominalpumping than observed in isolated females (solitary). This differsfrom the usual form of sexual communication in moths: female(chemical) signalers, male receivers, and a general lack ofinteraction among females. At mating, male U. ornatrix transfera large spermatophore that may enhance female reproductive successand which represents either mating effort or paternal investment.This action results in an extended postmating male refractoryperiod leading to a female-biased operational sex ratio. Weargue that this biased sex ratio generates intrasexual competitionamong females, to which they respond by elevating signalingeffort such that the likelihood of at least matching their neighbors'signals is increased. In the field, U. ornatrix are clusteredaround patches of host plants, and we also explore the possibilitythat pheromonal chorusing is driven by cooperation among groupsof related—or nonrelated—females.     

甜菜夜蛾交配行为和能力

在(27±1)℃,光周期L14∶D10的条件下对甜菜夜蛾I>Spodoptera exigua的交配行为及能力进行了研究。结果表明：成虫在羽化当晚即可进行交配,交配率以羽化后头三个晚上的较高(>82%),但从第4天起则显著下降。成虫一天中的交配时间出现于23:30～05:30之间,交配高峰出现在01:30～02:30和03:00～04:00 之间, 其中以第1高峰的发生频率较高。成虫交配持续时间从22～191 min不等,但以30～60 min的为多(40.8%, n=97), 60～90 min的次之(19.4%),超过180 min的较少(10.2 %)。另外,交配持续时间与蛾龄紧密相关。蛾龄越大,交配持续的时间越长,且差异显著。雄蛾一生的交配能力由1～11次不等,但受性比的影响显著：在性比为1∶1的条件下,雄蛾平均交配次数仅为3.0 次,而在2♀∶1♂至5♀∶1♂时,则增加到5.1～6.0 次。雌蛾交配比例及次数受性比的影响也很大：没有交配的雌蛾比例从1∶1时的8.3%增加到5♀∶1♂时的32%,仅交配一次的比例从16.7%增加到38.7%,而交配≥5 次的比例则从 25%下降到0。最后,对这些结果在甜菜夜蛾防治中应用的可能性进行了讨论。     

蜜露对天敌昆虫生长繁殖及搜寻行为的影响

已有研究表明:同翅目昆虫蜜露对一些天敌昆虫有着特殊的作用。一方面,蜜露可用来补充营养,从而促进天敌若虫死亡率下降、成虫寿命延长以及繁殖力提高;另一方面,蜜露作为天敌搜寻行为的信息物质。而人工蜜露在很多情况下对部分天敌也具有上述2方面的作用。文章就此内容的研究进展作一概述,以期促进蜜露在天敌昆虫人工饲养、害虫综合防治以及其他方面发挥作用。     

蜘蛛繁殖行为研究进展

蜘蛛的繁殖行为可以分为求偶行为、交配行为、产卵和携卵行为、携幼行为,本文根据国内外研究进展,对蜘蛛的繁殖行为进行简要综述.     

Reproductive ecology of the river lamprey

The reproductive ecology of river lamprey Lampetra fluviatilis was investigated during the spawning period 2003 in the River Derwent, north‐east England. Over this period 1199 ± 104 individuals day⁻¹(mean ±  s . d .) were counted on one spawning site (area c . 450 m²), but mark‐recapture estimates suggested that >5000 river lamprey used this site over the same period and egg deposition was estimated as 168 000 eggs m⁻². The operational sex ratio of river lamprey in spawning clusters changed between spawning phases, from domination by females during the nest‐building phase (male : female ratio, 1 : 3·46), to a preponderance of males during the spawning phase (male : female, 1 : 0·37), followed by a return to a majority of females after spawning (male : female, 1 : 3·74). Recapture data showed that >97% of recaptured, tagged males were recorded at two or more nests, whereas almost 50% of recaptured, tagged females were recorded at the same nest, suggesting a promiscuous mating system, with a tendency towards polygyny within the population. Within the lower 80 km of the River Derwent and its tributaries, evidence of river lamprey spawning was found at only six sites, and most spawning (>80% of the observed spawning population) was at one site.     

Interactions between male moths of the lightbrown apple moth, Epiphyas postvittana (Walker) (Lep.: Tort.), landing on synthetic sex pheromone sources in a wind-tunnel

Abstract. This study was designed to determine whether landings of males of Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae) on synthetic sex pheromone sources are influenced by other males which have preceded them in flying to and landing on the sources. The investigation comprised two separate experiments. In one, using a single pheromone source, insects released singly were compared with insects released in groups of three, and in the other, insects released in groups of five were presented with a choice between two identical sources. The resolution for changes in attractancy was higher in the choice experiment which demonstrated an increase in attraction for a source on which males had already landed and remained whilst the new male flew towards it. A single resident insect increased the source attractancy by a factor of 1.40 and a pair of insects by 1.77 compared with an empty source. With the single sources the data exhibited the same trend but the result was rendered not significant by an insufficient amount of data, although approximately equal times were allocated to each experiment. To achieve a significant result with the single sources at least 6 times as much data would need to be collected.     

榆木蠹蛾生殖行为及性信息素产生与释放节律

通过室内饲养与野外观察榆木蠹蛾Holcocerus vicarius (Walker)成虫的羽化、交尾、产卵行为,触角电位反应测定处女雌蛾性信息素产生与释放节律,旨在为榆木蠹蛾性信息素的鉴定和合成奠定基础。结果表明：榆木蠹蛾羽化行为全天可见,主要集中在15:00－19:00。成虫羽化当日即可交尾,21:30－0:30进行婚飞和交尾,交尾高峰出现在晚23:00左右,光期未见交尾。随着日龄的增加,召唤时间前移并且延长,2～3日龄处女雌蛾召唤时间早于1日龄雌蛾,交尾时间较短;雌蛾在羽化1 d后达到性成熟,2日龄雌蛾交尾百分率最高,达41.8%。雌蛾将产卵器伸出寻找缝隙处产卵,分多处产卵,雌虫最高产卵量达720粒,最低产卵量为105粒,卵期为12～22 d不等,孵化率为72%～88%。羽化当晚的雌蛾体内性信息素含量较低,第2天最高,以后逐日下降;2日龄榆木蠹蛾处女雌蛾性信息素的产生量从晚17:00起逐渐增加, 21:30－22:00时最高, 22:00后逐渐减小。雄蛾触角电位反应在22:30最强。21:30－23:00是雌蛾产生和释放性信息素的高峰期。榆木蠹蛾的羽化、交尾存在一定的时辰节律,通过处女雌蛾的野外诱集试验证实了性信息素释放与交配行为在时辰节律上的一致性。     

Development of pheromone-based mating disruption for control of the eye-spotted bud moth, Spilonota ocellana

The potential for pheromone-based mating disruption of eye-spotted bud moth (ESBM), Spilonota ocellana (Denis & Schiffermüller) (Lepidoptera: Tortricidae), in apple orchards in the Okanagan Valley of British Columbia was examined in small-plot trials. In a preliminary experiment, treatment of the orchard atmosphere with a 99:1 blend of Z8-tetradecenyl acetate (Z8-14:OAc) and Z8-tetradecenyl alcohol (Z8-14:OH) completely inhibited captures of male ESBM in pheromone-baited traps, but treatment with Z8-14:OAc alone did not. Therefore, all subsequent trials used the two-component blend as a disruptant. Mean catches of male ESBM in traps baited with 0.1, 1, 10, or 20 mg of 99:1 Z8-14:OAc and Z8-14:OH were significantly reduced (81–97%) in pheromone-treated plots relative to similar traps placed in control plots. In both control and treated plots, there was a significant positive relationship between trap bait dose and trap catch. In pheromone-treated plots, this suggests that high doses of trap baits over-ride the camouflage effect of disruption or overcome the effect of sensory adaptation and habituation. The number of virgin-female baited traps capturing at least one male ESBM was reduced by 96%, and mating of virgin females on mating tables was reduced by 95% in plots treated with the two-component pheromone. The total amount of Z8-14:OAc released from pheromone disruption dispensers during the latter field trials was estimated to average 6.4 g ha^-1 over 11 days or 26.4 mg ha^-1 h^-1. The low levels of Z8-14:OH released from disruption dispensers could not be estimated by GC analysis. Dispensers loaded with a 99:1 blend of Z8-14:OAc and Z8-14:OH were highly attractive to males in baited traps, indicating that they have the potential to induce false trail following.     

Effects of delayed mating on the fecundity,fertility and longevity of females of diamondback moth,Plutella xylostella

Abstract The effects of delayed mating on the copulation duration, female fertility, fecundity, egg fertility, longevity and the number days alive after mating of females of diamondback moth (DBM), Plutella xylostella, were studied. When male mating was delayed, the female fertility, fecundity, egg fertility, longevity and number days alive after mating of DBM decreased, and there was a negative correlation between the age of the moth with those variables except copulation duration. When female mating was delayed, the female fertility, fecundity, percent egg fertility and number days alive after mating of DBM also decreased, but the longevity increased, which also showed a negative relationship between the age of the moth with the variables except copulation duration and longevity. When both males and females delayed mating, the female fertility and fecundity decreased; egg fertility was affected marginally, and the longevity of females increased. The moth age was negatively correlated with those variables.     

胸窗萤的生殖习性

研究胸窗萤Pyrocoelia pectoralis Olivier雌、雄成虫生殖系统、交配和产卵行为。描述雌雄成虫在求偶过程中的多种行为:寻找、竞争、抱对、交配、受精。雌雄交配时间可持续(82.5±34.8)min(n=15),雌雄均有多次交配现象。雌虫羽化后可立即交配产卵。在(25±2)℃室温下,雌虫寿命8.87±2.06d(n=30),雌萤平均产卵量为72.03±34.38粒(n=30),产卵量与雌虫体重呈正相关关系(y=235.28x-20.38,R2=0.7283,df=43,P<0.01);而产卵日龄与每日产出率呈指数函数关系(y=1.5339e-0.9148x,R2=0.9987,df=5,P<0.01)。因子分析结果显示,影响雌虫生殖力的因子可以归为外部形态因子和内在生理因子。     

萼花臂尾轮虫交配行为和受精作用研究

萼花臂尾轮虫的交配行类在致可分为５个阶段,除雌雄性比为１：２和１３时混交雌体的受精率为１００％外,其余性比下混交雌体的受精率皆无显著的差异。可受精的混交雌体自分率和具有精能力的雄性百分率皆降年龄的增大而下降,的有的混交雌体在出生后的４ｈ内均易于受精,以后随着雌长（Ｘ,ｈ）的增加,可受精的混交雌体百分率（Ｙ,％）呈非线性下降,Ｙ＝１６６．６３８６－１７．８１３Ｘ＋０．４８３７Ｘ＾２,当岭长达１８ｈ时     

Emergence and mating behavior of the oriental fruit moth Cydia molesta (Lepidoptera: Tortricidae) and its potential for reproduction

The Oriental fruit moth, Cydia molesta (Busck, 1916) (Lepidoptera: Tortricidae), is a key pest of fruit and is widely distributed around the world. There are important connections between its behavior and biology and its management in agriculture, but few studies have investigated the associations between adult behaviors and oviposition. In this study, adult emergence, mating, and reproduction were investigated under laboratory and field conditions. The ratio of females to males at eclosion was approximately 1:1. When one virgin female had access to one virgin male, 66% and 34% of the couples copulated just once and twice, respectively; and the infertility rate of eggs (21.39 ± 1.25%) did not vary daily. Males, given access to one new female daily, could copulate multiple times, whereas females seldom mated more than once, indicating a male-biased operational sex ratio, but mating status of the male parent had no effect on progeny egg reproduction. Also, the number of eggs that hatched by all female partners of a male was inversely proportional to copulation duration for the female laying the eggs for total female reproductive success; and the number of eggs laid by all female partners of a male was proportional to their number of matings for total male reproductive success. However, the total number of eggs that hatched did not significantly differ for eggs laid by a female given new virgin males daily for mating (17.75 ± 4.28) versus eggs laid by virgin females (19.17 ± 7.51) presented daily with a male that re-mated daily with the series of females. Therefore, our results showed that females engaged in mate choice and males engaged in mate competition, affecting egg production, a factor that may be used to enhance mating disruption technology against Cydia molesta.     

Application of synthetic sex pheromone for management of diamondback moth, Plutella xylostella, in cabbage

Over a 2-year period field trials were conducted to assess the potential to disrupt mating ofPlutella xylostella (L.) using a commercial rope formulation of a 70:30 mixture of (Z)-11-hexadecenal and (Z)-11-hexadecenyl acetate, two components of the sex pheromone of the female. Screened field cages were placed into blocks of cabbage which were either treated with the pheromone or left untreated. Different densities of P. xylostella pupae were placed into each cage and then larval and pupal counts were made of the subsequent generation. In addition, sentinel females at mating stations were placed in each cage to assess the influence of the pheromone on the ability of males to locate and mate with females. Likewise, we used pheromone traps to assess whether the pheromone treatment influenced the ability of males to locate a pheromone source. In both years larval and pupal populations, produced as a result of the original inoculation, did not differ between pheromone-treated and untreated fields. The effect of pheromone treatment on larval and pupal numbers did not change with changes in inoculated P. xylostella density, however, the density of P. xylostella released caused significant differences in the density of the subsequent generation. No significant differences were detected between the number of sentinel female adult P. xylostella that successfully mated in pheromone-treated fields compared with untreated fields. Significant differences in the numbers of male P. xylostella caught in pheromone-baited traps occurred between pheromone-treated and untreated fields in the first trial of 1993, and in the first trial in 1994 but not in the second trial. Such differences are often thought of as indications of mating disruption, although our other data presented in this study and reports from other studies indicate this is not always the case. Previous studies on mating disruption of P. xylostella in larger scale field tests have been performed but the results have been variable and often ambiguous. Overall, our results indicate that mating disruption of P. xylostella with the present technology does not appear to work even under the very controlled situations which we utilized to eliminate insect movement between plots.     

The courtship behavior of the cabbage moth,Mamestra brassicae (Lepidoptera: Noctuidae), and the role of male hair-pencils

The courtship behavior of the cabbage moth, Mamestra brassicae(L.), was studied in moving air conditions in a wind tunnel, using video techniques. Quantitative analyses were undertaken to determine the behavioral sequence occurring in the courtship. Comparison of successful and unsuccessful courtship suggested that courtship success was more dependent on the behavior of the female than that of the male. In an attempt to elucidate the function of the male hair-pencils (HPs), courtships involving males without HPs were also studied. HP removal did not affect the overall courtship success rate of males, but detailed analysis showed significant changes infernale behavior during such courtships. HP removal also affected female behavior following pair formation, with females struggling more when paired with males without HPs. Consequently, it is proposed that the HP volatiles act as an arrestant for the female, both during courtship and after pair formation, to increase female acceptance and to prevent premature termination of copulation. Experiments were also conducted to test previous hypotheses for HP function. However, no evidence was found to suggest that the HP volatiles in M. brassicaeact to attract females, affect female calling behavior, or affect the behavior of other males. A further possible function of HPs in defense is discussed.     

Mating Behavior and Reproductive Potential in the Turnip Moth Agrotis segetum (Lepidoptera: Noctuidae)

We investigated the lifetime mating potential and the reproductive behavior of male and female turnip moths Agrotis segetum (Schiff.) under field and laboratory conditions. The sex ratio was 1 : 1 in a lab-reared population as well as in two wild populations. Males were capable of mating repetitively a relatively large number of times (mean of 6.7 ± 2.7 matings) when given access to new virgin females throughout their lifetimes. Females seldom mated more than once (mean ± 1.3 ± 0.6 matings), indicating a male-biased operational sex ratio. The mean potential lifetime mating was five times higher in males, while the coefficient of variance was lower in males. There was no differences in longevity between animals that were allowed to mate and animals not allowed to mate, indicating no direct costs or benefits of mating in physiological terms. In males, the number of matings was positively correlated with longevity, but this was not the case in females. Nor was there a correlation between the number of female matings and the number of fertilized eggs. There was a negative correlation between the number of eggs fertilized and the number of times males had previously mated, indicating that male ejaculates were limited. Male spermatophore size also decreased with number of achieved matings. Laboratory-reared females attracted males in the field throughout their lifetimes, with a peak at 3–7 days of age. Wild males, allowed to choose between pairs of caged females in the field, were attracted in equal numbers to females of different ages. Females did not show any mate-rejection behavior in the field. They mated with the first male that courted them. No incidence of mate replacement by males arriving later to already courted females were recorded.     

Sex,reproductive cycle and variations in the fecundity of the family schilbeidae (Osteichthyes : Siluriformes) in Lake Kainji,Nigeria.

The sex, reproductive cycle and variations in the fecundity of the family Schilbeidae (Osteichthyes : Siluriformes) in Lake Kainji, were investigated. Sexual differences in size and morphology were found to exist in all species. Sex ratio varied with species and season. There were more females than males in the population. Size at maturity varied from species to species with the males attaining maturity at a slightly lower length than the females. Breeding condition was attained mainly during the rains in Eutropius niloticus, Schilbe mystus and Siluranodon auritus and in the dry and rainy seasons in Physailia pellucida. Spawning occurred once during the breeding season in E. niloticus and S. mystus; and more than once during the prolonged breeding season in P. pellucida. Condition factors did not show any correlation with maturation of gonads. Fecundity was found to vary from species to species.     

Isolation of microsatellite loci in the codling moth,Cydia pomonella (Lepidoptera: Tortricidae)

Cydia pomonella L. is an important insect pest of pome fruits worldwide. We have isolated and characterized 17 microsatellite loci from the enriched genomic libraries constructed using a biotin/streptavidin capture protocol. Among these loci, 11 were scored polymorphic when 50 individuals from a laboratory population were screened. Their alleles numbered two to four, with the observed heterozygosity (H_O) ranging from 0.114 to 0.404. Successful amplification was obtained for all these loci when the designed primers were tested, showing the promise of use in genetic mapping and population studies.     

Conspecific females promote calling behavior in the noctuid moth,Pseudaletia adultera

Changes in female calling behavior in response to the presence of conspecific pheromones (pheromone autodetection) have been demonstrated in a number of moth species. However, the observed changes vary between species, and several ecological and adaptive explanations for autodetection have been proposed. We studied the effect of conspecific females on the calling behavior of the noctuid moth Pseudaletia adultera (Schaus) (Lepidoptera: Noctuidae, Hadenini), by comparing the age of first calling, as well as the onset and pattern of calling, when females were held individually or in the presence of conspecifics. Grouped females started calling at a lower age, a higher percentage of females called during the scotophase, and they called longer compared to females held in isolation. We also demonstrated that female antennae respond to each of the three main components of the sex pheromone – (Z)‐11‐hexadecen‐1‐ol, (Z)‐11‐hexadecen‐1‐yl acetate, and (Z)‐11‐hexadecenal – and that the response patterns differed from those of male antennae. By calling more and extending her calling window in presence of conspecific females, a female may increase her chances of accessing males. However, the potential benefits need to be considered within an ecological context, considering factors such as migration, oviposition, and foraging.