The concept of fecundability derives its importance for the study of human fertility from the fact that it is one of the principal determinants of fertility and is a major standard by which the impact of fertility reg...The concept of fecundability derives its importance for the study of human fertility from the fact that it is one of the principal determinants of fertility and is a major standard by which the impact of fertility regulation can be assessed;very few attempts have been made in Bangladesh for estimating fecundability. This study attempts to evaluate the levels, patterns, and trends of fecundability and identify the factors affecting fecundability in Bangladesh based on national surveys of Bangladesh Demographic and Health Survey (BDHS) 2007-1994. Total 9703 ever married women are included in the bivariate and multivariate analyses which reveal that age at first birth, age at marriage and marital duration play an important role in influencing marriage to first birth interval positively and thus fecundability negatively. Although fecundability in Bangladesh showed an increasing trend, but it is very low compared to developed and developing countries.展开更多
The nutritional status of an individual can significantly influence its life history traits,including development,growth,reproduction,and survival.In the predatory mite Phytoseiulus persimilis Athias-Henriot(Acari:Phy...The nutritional status of an individual can significantly influence its life history traits,including development,growth,reproduction,and survival.In the predatory mite Phytoseiulus persimilis Athias-Henriot(Acari:Phytoseidae),the plasticity of life history traits,such as developmental time and size at maturity,is influenced by the quality and quantity of food.This study aimed to investigate the effects of dietary restriction at different life stages(i.e.,juvenile,early adulthood,and later adulthood)on the lifespan and fecundity of P persimilis.We found that reduced dietary intake during early adulthood resulted in a shorter lifespan for both male and female P persimilis.Furthermore,this study demonstrated a sex-specific response to dietary restriction:it extended the lifespan of males but reduced that of females during later adulthood.Diet restriction during the postovipositional period of females showed the most variable life history trait response.Our results showed that the impact of diet restriction at different life stages can have combined influences on the postovipositional duration of P persimilis,where the individuals receiving diet restriction during immature development and early adulthood had a greater reduction in ovipositional duration as those experiencing diet restriction during late adulthood.In addition,we observed a positive correlation between the lifespan and fecundity of females,with higher prey availability increasing both.The insights obtained from our research contribute to a better understanding of the aging process and dietary requirements of P persimilis,which can facilitate the development of more effective biological control strategies using this predator for spider mites in agriculture.展开更多
Mounting evidence suggests that male sperm may be gradually depleted after consecutive matings,resulting in the decline of female reproductive output in insect species.It is predicted that females may employ adaptive ...Mounting evidence suggests that male sperm may be gradually depleted after consecutive matings,resulting in the decline of female reproductive output in insect species.It is predicted that females may employ adaptive strategies to avoid the sperm-depleted males,such as mating multiply with different males and/or discriminating against previously mated males(MMs).Similarly,males may exhibit adaptive behaviors toward females varying in mating status.However,in spiders with males lacking primary copulatory organs and their pedipalps modified to transfer sperm,there are few studies on male mating potential and previous mating experience on their subsequent mate choice.In this study,we used a polyandrous crab spider,Ebrechtella tricuspidata,a sit-and-wait predator with female-biased sex ratio as a model system to ascertain whether 1)male mating experiences influence female reproductive fitness;2)females respond differently to males varying in mating status;and 3)males respond differently to females varying in mating status.Our results showed that female fecundity was independent of male mating experiences,but female fertility markedly declined with the increase of male previous mating experiences in the first eggsac.Counter to our predictions,females preferred to choose and mate with the larger males,regardless of their mating status.In contrast,male mating status influenced their mating preference toward females.Virgin males did not show any preference between virgin and mated females;however,MMs were more likely to prefer the virgin females over the mated ones.Overall,our results indicated that female choice depended primarily on male relative size rather than male mating status,whereas male choice depended on female mating status,Depending on the investigation of reproductive dynamics and mate choice in E.tricuspidata,the study will provide valuable insights into the adaptive behaviors of both males and females exhibiting toward mates varying inmating status.展开更多
The red tilefish Branchiostegus japonicus is an economically important demersal fish species with high-quality.However,research on its reproductive biology and population structure characteristics is limited.To better...The red tilefish Branchiostegus japonicus is an economically important demersal fish species with high-quality.However,research on its reproductive biology and population structure characteristics is limited.To better understand the reproductive biological features of B.japonicus,a study was conducted on 461 individuals collected from the East China Sea(27°00′-31°00′N,122°30′-127°30′E)from March to December in 2021.This study analyzed the relationship between standard length and the body weight,and detected the sex ratio,length at first sexual maturity,reproductive period,fecundity,and spawning type of this species.The results revealed a power function relationship between body weight(W)and standard length(L)in the samples as the following regression equation:W=0.000014 L^(3.16)(R^(2)=0.956).The sex ratio was close to 1:1(χ^(2)=1.11,P>0.05),and the sex ratio exhibited significant differences according to different standard lengths.Using the logistic equation,we estimated that 50% of B.japonicus individuals had a standard length at sexual maturity of L_(50)=210 mm.By analyzing the monthly variation in the gonadal index and the proportion of each stage of ovarian development in each month,we assumed that the spawning period of B.japonicus occurred from May to November,and the peak spawning period occurred from June to October.The absolute fecundity was 51441±33232 eggs,the relative fecundity at the standard length was(210±117)eggs mm-1,and the relative fecundity relative to body weight was(184±89)eggs g^(-1).The distribution of the egg diameter of B.japonicus had only one obvious peak,indicating the spawning pattern of B.japonicus was once a year.This study updated and enriched the basic biological data of B.japonicus,which is beneficial for obtaining a better understanding of its population dynamics,and promoting the conservation and sustainable utilization of B.japonicus in East China Sea.展开更多
5-hydroxytryptamine(5-HT)is a biological monoamine neurotransmitter in the central nervous system and gonads of crustaceans to induce gonadal maturation.To better understand the effects of 5-HT and its receptors on re...5-hydroxytryptamine(5-HT)is a biological monoamine neurotransmitter in the central nervous system and gonads of crustaceans to induce gonadal maturation.To better understand the effects of 5-HT and its receptors on reproductive development in Artemia,a 5-HT type 7 receptor gene(5-HT_(7Ar))was identified in parthenogenetic Artemia and characterized.Sequence analysis revealed that the open reading frame of 5-HT_(7Ar) encodes a 414-aa protein.5-HT_(7Ar) showed higher expression in both brain and ovary at early embryo stage,5-HT_(7Ar) could be detected during ovarian development and the highest expression was observed at early embryo stage.Silencing of the 5-HT_(7Ar) in Artemia at early embryo stage decreased significantly the expression level of 5-HT_(7Ar) gene and protein at late oocyte,early embryo,and late embryo stage.Moreover,silencing of the 5-HT_(7Ar) resulted in a decreased fecundity,which corresponds to abnormal oocytes during the embryo development.Artemia tended to produce nauplii after the silencing of 5-HT_(7Ar),indicating that 5-HT_(7Ar) may also involve in the determination of its reproduction mode.The findings of this study provide an insight into the regulation of reproductive development in Artemia and the function of 5-HT_(7Ar).展开更多
17β-Estradiol(E2)has been widely detected in natural water and treatment with E2 induces potential endocrine disrupting effects in fish.However,effects on fish fecundity and steroid system after treatment with enviro...17β-Estradiol(E2)has been widely detected in natural water and treatment with E2 induces potential endocrine disrupting effects in fish.However,effects on fish fecundity and steroid system after treatment with environmentally relevant concentrations of E2 for the full sexual maturation cycle remain unclear.In this study,zebrafish were treatment with 0,10 or100 ng/L E2 from embryo to adult stage,and effects on gonadal development and differentiation,steroid hormone levels,transcription of genes associated with the hypothalamic-pituitary-gonadal-liver(HPG)axis in adults and fertilization rate of offspring were assessed.The results showed that treatment with E2 lead to increased number of feminization in zebrafish.In females,E2 decreased cumulative amount of spawning and inhibited the maturation of oocyte.In males,E2 inhibited the maturation and motility of sperm,as well as decreased the movement speed of sperm.These adverse effects on sperm might be responsible for the reduced fertilization observed in offspring.In addition,treatment with E2 changed the levels of steroid hormones in zebrafish gonad and altered the transcriptional levels of genes associated with HPG axis,which is responsible for the regulation of germ cells maturation and gonadal development in zebrafish.Overall,these results suggested that treatment with environmentally relevant concentrations of E2 for the full sexual maturity cycle resulted in adverse effects on reproduction in zebrafish.展开更多
To understand the reproductive biology of Hemitripterus villosus in the Bohai Strait,and fill the key knowledge gap in verifying reproductive seasonality and documenting gonadotropin dependent reproductive cycle of th...To understand the reproductive biology of Hemitripterus villosus in the Bohai Strait,and fill the key knowledge gap in verifying reproductive seasonality and documenting gonadotropin dependent reproductive cycle of this species,a year-round detail study was conducted for the first time.In total,263 individuals were randomly sampled off the coasts of the Bohai Strait.Results show that and the overall female-to-male ratio(1.35:1)did not differ significantly from the 1:1 sex ratio.The length and weight relationship for females and males were regressed,depicting an isometric growth for both sexes.Four reproductive phases of the complete gonadotropin dependent reproductive cycle in both sexes were identified.The monthly variations in the gonadosomatic and hepatosomatic indexes for both sexes further indicated that this species spawns a single batch of eggs per year and the peak spawning period is from October to December.The average diameter of eggs ranged from 2.10 to 3.57 mm.The length at first sexual maturity was 224.87 mm for females and 241.26 mm for males.Significant positive relationships between absolute fecundity and fish size,and also gonadal weight were observed.H.villosus from the Bohai Strait exhibited smaller body size,smaller egg diameter,lower gonadosomatic index,lower absolute fecundity,and higher population extinction risk than the other populations’studied previously.Our findings contribute to understanding the status of this isolated westernmost population,and we emphasize that more efficient protection measures for the species and control measures are urgently required to improve the coastal environment in the Bohai Strait.展开更多
We studied sexual dimorphism in body size and shape and female reproductive characteristics in the Hainan Water Skink(Tropidophorus hainanus)from Hainan,South China.In our sample the largest female and male were 61.1 ...We studied sexual dimorphism in body size and shape and female reproductive characteristics in the Hainan Water Skink(Tropidophorus hainanus)from Hainan,South China.In our sample the largest female and male were 61.1 and 55.2 mm snout-vent length(SVL),respectively.The mean SVL was larger in adult females(52.0 mm)than in adult males(48.3 mm).Juveniles were sexually dimorphic in head length but not in other examined morphological variables.Adult males were longer in head length and shorter in abdomen length and fore-limb length than adult females of the same SVL.Ontogenetic shifts in sexual dimorphism in body shape were evident,as revealed by the fact that morphological differences between the sexes were more pronounced in adults than in juveniles.Females produced a single litter of 3–6 offspring per season from early August to early September.Litter size,litter mass and offspring(neonate)mass were positively related to female SVL.Neonate mass was independent of relative fecundity.From the above findings we draw three main conclusions.First,females are the larger sex in T.hainanus,and sexual dimorphism in body shape is more pronounced in adults than in juveniles.Second,larger female T.hainanus produce more and larger offspring and thus heavier litters than smaller ones.Third,the offspring size-number trade-off does is not evident in T.hainanus.展开更多
[Objective] The aim was to study on the effect of hosts on development and reproduction of mealybug （Phenacoccus solenopsis Tinsley）. [Method] Observation was conducted on developmental durations and fecundity of Ph...[Objective] The aim was to study on the effect of hosts on development and reproduction of mealybug （Phenacoccus solenopsis Tinsley）. [Method] Observation was conducted on developmental durations and fecundity of Phenacoccus solenopsis Tinsley fed on Gossypium spp., Nicotiana tabacum, Solanum tuberosum L and Hibiscus rosa-sinensis. [Result] There were differences among all durations, generation durations and fecundities of the mealybug adult females. Specifically, the generation durations on cotton （Gossypium spp.）, tobacco（ Nicotiana tabacum）, potato （Solanum tuberosum L） and Hibiscus rosa-sinensis were 30.2, 28.2, 37.3, and 27.7 d, and the fecundities per female were 626.0, 417.2, 552.5, and 183.2 ind., respectively. [Conclusion] The mealybug would have strong pontential in population growth when fed on cotton, tobacco and potato.展开更多
The World Health Organization （WHO） has extensively revised its manual for semen analysis, and seeks to provide reference limits for semen quality parameters. This raises the question of what is meant by ＇normal＇ ...The World Health Organization （WHO） has extensively revised its manual for semen analysis, and seeks to provide reference limits for semen quality parameters. This raises the question of what is meant by ＇normal＇ （excluding the use of this term to denote a Gaussian distribution）. It could be taken in a purely statistical sense, using a biologically arbitrary cut-off point to denote an abnormal level, typically the extreme 5 percent of the population. Alternatively, ＇normal＇ could be defined according to the biological concept of normality and abnormality, in terms of the point at which biological function becomes impaired. Either of these can be used in descriptive epidemiology, for example, to study trends, but in the case of fertility, both semen quality and functional fertility （time to pregnancy） are continuous variables with no clear threshold. The WHO manual uses the biological meaning of normal, in that it provides the semen parameter distributions for men who have recently fathered pregnancies that took 12 months or less to conceive. However, what is really needed is the same information the other way around： given a particular semen test result, what should be expected in terms of ability to conceive, and how long it is likely to take. In considering epidemiological research, the focus has been mainly on internal comparisons, rather than reference limits, but it would be beneficial if more attention were paid to the absolute levels and to what these mean in terms of function--in other words, if the data were better calibrated biologically.展开更多
Several recent studies have shown that the fecundity of a man decreases progressively with sperm concentrations below 40 million spermatozoa per mL. Therefore, it is unfortunate that the new World Health Organization ...Several recent studies have shown that the fecundity of a man decreases progressively with sperm concentrations below 40 million spermatozoa per mL. Therefore, it is unfortunate that the new World Health Organization guidelines for semen analysis recommend lowering the lower cutoff value for normal sperm concentration from 20 to 15 million spermatozoa per mL. As a result large groups of subfertile men across the world may not receive appropriate andrological help in the future.展开更多
In December 11,2018,the fall armyworm(FAW),Spodoptera frugiperda invaded China and has since impacted local maize,sorghum and other crops.Here,we draw on laboratory experiments to show how different host crops(i.e.,ma...In December 11,2018,the fall armyworm(FAW),Spodoptera frugiperda invaded China and has since impacted local maize,sorghum and other crops.Here,we draw on laboratory experiments to show how different host crops(i.e.,maize,sorghum,wheat and rice)and artificial diet affect larval growth and adult reproduction of one local FAW strain.Larval diet affected development duration,pupation rate,survival and emergence rate of pupae,and S.frugiperda adult fecundity.FAW attained the slowest larval development(19.4 days)on sorghum and the fastest(14.1 days)on artificial diet,with larvae attaining 99.6%survival on the latter food item.On rice,FAW larvae attained survival rate of 0.4%and were unable to pupate successfully.Pupation rate and pupal survival varied substantially between artificial diet and live plantlets at different phenological stages.Pupal weight was the highest(0.26 g)on artificial diet and the lowest(0.14 g)on sorghum,while FAW females reached the highest fecundity(699.7 eggs/female)on 2-leaf stage maize.Egg hatching rate equaled 93.6%on 4-or 5-leaf stage maize and 36.6%on artificial diet.FAW intrinsic rate of natural increase and the finite rate of increase varied between larval diets,reflecting how young maize leaves are the most suitable diet.Our findings can help to refine laboratory rearing protocols,devise population forecasting models or guide the deployment of‘area-wide’integrated pest management(IPM)modules in FAW-invaded areas of China and other Asian countries.展开更多
The fall armyworm(FAW),Spodoptera frugiperda,is a newly invasive,widespread agricultural pest in China.Understanding the suitability of the main field crops in Chinese agricultural system as host for this polyphagous ...The fall armyworm(FAW),Spodoptera frugiperda,is a newly invasive,widespread agricultural pest in China.Understanding the suitability of the main field crops in Chinese agricultural system as host for this polyphagous herbivore is especially important for making control strategy.Here,after FAWs were fed three important oil-bearing crops(oilseed rape,soybean and sunflower)planted in China and resultant population parameters were compared using the age-stage,two-sex life table method,survival of larvae on soybean was significantly lower than that on oilseed rape and sunflower.Developmental duration of larvae on soybean was also the longest(23.3 days).The highest pupation rate was recorded on sunflower.The highest pupal mass(0.19 g)was attained on oilseed rape,significantly higher than on the other host plants;the lowest mass was on soybean(0.15 g).On soybean,oilseed rape and sunflower,respectively,the average generation period was 42.21,39.10 and 40.44 d;the intrinsic rate of increase(r)was 0.0844,0.1041 and 0.1134;the finite rate of increase(λ)was 1.0881,1.1098 and 1.1202.While the most suitable host plant overall was sunflower,S.frugiperda completed development and increased its population on all three host plants.Thus,soybean,oilseed rape and sunflower were all suitable for FAW,and population monitoring and management of FAW in these crops should be increased.展开更多
Breeding strategies of Acrossocheilus fasciatus were studied from 592 specimens collected monthly during May 2007 and April 2008 in the Puxi Stream of the Huangshan Mountain. Sex ratio of the studied population was 0....Breeding strategies of Acrossocheilus fasciatus were studied from 592 specimens collected monthly during May 2007 and April 2008 in the Puxi Stream of the Huangshan Mountain. Sex ratio of the studied population was 0.90 ： 1 （ ♀ ： ♂ ）, not significantly different from 1 ： 1. Both sexes reached their first sexual maturity at age 2 （the second calendar year of their birth）. Fifty percent of females and males reached maturity at a total length of 69.75 mm and 69.36 mm respectively, and the minimum total length was 61.54 mm and 58.96 mm, respectively. Based on the monthly changes in gonado-somatic index and egg- development process, the breeding season of the population was from May to August, with one obvious interval （in June） occurring in the breeding activity for the females. The nonsynchronous development of oocytes observed in mature ovaries indicated that A. fasciatus is a batch spawner. Absolute fecundity of A. fasciatus ranged from 308 to 2002 eggs with a mean of 857 eggs, increased significantly with total length, and was significantly different among three age groups. Relative fecundity ranged from 38.63 to 71.70 egg/g with a mean of 53.29 egg/g, and was not significantly different among the three age groups. It was suggested that these reproductive characteristics were adaptive strategies for A. fasciatus to acclimatize to lotic water where environmental factors were unstable but predictable [ Current Zoology 55 （5） ： 350 - 356, 2009].展开更多
Although amphioxus is widespread in temperate and tropical seas,its population is diminishing be-cause of environmental pollution.To keep the population of this evolutionarily important animal fromdiminishing,study on...Although amphioxus is widespread in temperate and tropical seas,its population is diminishing be-cause of environmental pollution.To keep the population of this evolutionarily important animal fromdiminishing,study on its reproduction and development is necessary.The main findings in this study onthe spawning and fecundity of the amphioxus reared in laboratory and its larval development are as fol-lows.1.Water temperature markedly affected the spawning.It spawned only when water temperature reached 21℃.2.Spawning of the amphioxus in laboratory was markedly extended.Initially,the amphioxus spawned at about 7:00 PM,but spawning time was postponed as spawning days went on.3.The number of eggs produced by a female ranged from 1400 to 12800,average of 5800.This al-so represents the fecundity of the amphioxus because it shedded all eggs within the ovary at a time.4.During the first few months of life of the amphioxus,its growth rate changed seasonally.Thegrowth rate in summer and fall was greater than that展开更多
A series of tests (lethal,sublethal,and behavioral) on earthworms were conducted as an eco-assessment of pesticides.In this study,the toxicity of cypermethrin-contaminating soil on adult and juvenile earthworms was as...A series of tests (lethal,sublethal,and behavioral) on earthworms were conducted as an eco-assessment of pesticides.In this study,the toxicity of cypermethrin-contaminating soil on adult and juvenile earthworms was assessed.Beside the acute and chronic tests,an avoidance response test was carried out.It was shown that the all-round toxicity from cypermethrin was weak on adult earthworms.Compared with adult earthworms,the toxicity of juvenile earthworms from cypermethrin especially chronic toxicity increased...展开更多
The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera （Htibner）, fed on cotton bolls grown under elevated CO2 （double-ambient vs. ambient） in open-top cha...The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera （Htibner）, fed on cotton bolls grown under elevated CO2 （double-ambient vs. ambient） in open-top chambers were examined. Significant decreases in protein, total amino acid, water and nitrogen content and increases in free fatty acid were observed in cotton bolls. Changes in quality of cotton bolls affected the growth, development and food utilization of H. armigera. Significantly longer larval development duration in three successive generations and lower pupal weight of the second and third generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower fecundity was also found in successive three generations of H. armigera fed on cotton bolls grown under elevated CO2. The consumption per larva occurred significant increase in successive three generations and frass per larva were also significantly increased during the second and third generations under elevated CO2. Significantly lower relative growth rate, efficiency of conversion of ingested food and significant higher relative consumption rate in successive three generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower potential female fecundity, larval numbers and population consumption were found in the second and third generations of cotton bollworm fed on cotton bolls grown under elevated CO2. The integrative effect of higher larval mortality rate and lower adult fecundity resulted in significant decreases in potential population consumption in the latter two generations. The results show that elevated CO2 adversely affects cotton bolls quality, which indicates the potential population dynamics and potential population consumption of cotton bollworm will alleviate the harm to the plants in the future rising CO2 atmosphere.展开更多
We used the Chinese skink Eumeces chinensis as a model animal to study the effects of tail loss on reproductive in- vestment and offspring traits. A total of 147 wild-captured adult females were divided into four grou...We used the Chinese skink Eumeces chinensis as a model animal to study the effects of tail loss on reproductive in- vestment and offspring traits. A total of 147 wild-captured adult females were divided into four groups according to their tail con- ditions. Tail breaks occurred most frequently in the proximal portion of the tail and least frequently in the distal portion, with the middle portion in between. This finding suggests that tail breaks occurring in nature often entails substantial energetic costs in E. chinensis where the tail is a major site of energy storage. The proportion of females that laid eggs was higher in females with in- tact or completely regenerated tails than in those with broken tails. Following whole-tail autotomy, the clutch size was reduced by 17%, and the clutch mass was reduced by 14%. Females undergoing substantial tail autotomy reduced reproductive investment, and they did so by reducing the number but not the size of eggs produced. None of the egg and hatchling traits was affected by tail loss. Comparing our data with those reported for other oviparous and viviparous skinks allows us to draw two general conclu- sions： one is that fecundity （clutch or litter size） is affected by tail loss in all species so far studied, whereas offspring size is af- fected by tail loss in some species, but not in others; the other is that the reduction in fecundity following tail loss is more evident in species lacking abdominal fat bodies展开更多
Floral resources,such as carbohydrate-rich nectar or pollen,can bolster fitness and raise reproductive output of adult lepidopterans.Here,we used laboratory experiments to assess how those plant-derived foods impact a...Floral resources,such as carbohydrate-rich nectar or pollen,can bolster fitness and raise reproductive output of adult lepidopterans.Here,we used laboratory experiments to assess how those plant-derived foods impact adult fecundity,reproductive physiology and flight performance of an invasive strain of the fall armyworm,Spodoptera frugiperda(FAW;Lepidoptera:Noctuidae)in China.More specifically,supplementary feeding on bee pollen and honey enhanced FAW flight duration,testis size,ovarian development,longevity and adult fecundity.FAW adults attained the longest pre-oviposition(10.8 days)and oviposition period(6.8 days)and longevity(19.2 days)on 5%acacia honey.Upon access to 2.5%acacia honey and 2.5‰pine pollen,S.frugiperda attained the highest mating rate(79.7%),fecundity(644.9 eggs/female)and egg hatching rate(82.3%).Feeding on honey further delayed decay of male testes,while ovarian development was enhanced when female moths were allowed access to 2.5%honey and 2.5‰pine pollen.Upon feeding on 5%honey solution,S.frugiperda engaged in flight over the longest duration(9.5 h),distance(29.9 km)and speed(3.1 km h-1).Honey had a comparatively greater effect on the above parameters than pollen.Our findings help decipher FAW invasion patterns and population dynamics,facilitate the development of nutritional attractants,and contribute to integrated pest management of this newly-invasive pest in eastern Asia.展开更多
We examined sexual size dimorphism （SSD）, mating pattem, fertilization efficiency and female reproductive traits in two bufonid toads （Bufo gargarizans and Duttaphrynus melanostictus） to test the idea that importa...We examined sexual size dimorphism （SSD）, mating pattem, fertilization efficiency and female reproductive traits in two bufonid toads （Bufo gargarizans and Duttaphrynus melanostictus） to test the idea that importance of male body size for egg fertilization success depends on the mating pattern. Female-biased SSD was evident only in D. melanostictus. Female B. gar- garizans laid fewer larger eggs nearly three months earlier than did female D. melanostictus. Fertilization efficieneies on average were higher in B. gargarizans （95%） than in D. melanostictus （91%）. Though differing in the degree of SSD, body size, breeding season, clutch size, egg size and fertilization efficiency, the two toads were similar in four aspects： （1） both showed size-assortative mating; （2） females did not tradeoff egg size against egg number; （3） male size, clutch size and clutch dry mass were greater in male-larger than in female-larger pairs after accounting for female snout-vent length （SVL）; and （4） the ratio of male to female SVL did not affect fertilization efficiency. Our data show that： （1） a female preference for large males is likely not important in terms of egg fertilization success; （2） a male preference for large females is likely important because larger females are more fecund; and （3） size-assortative mating arises from a male preference for large females. Our study demonstrates that male size is not always important for egg fertilization success in anurans that show size-assortative mating.展开更多
文摘The concept of fecundability derives its importance for the study of human fertility from the fact that it is one of the principal determinants of fertility and is a major standard by which the impact of fertility regulation can be assessed;very few attempts have been made in Bangladesh for estimating fecundability. This study attempts to evaluate the levels, patterns, and trends of fecundability and identify the factors affecting fecundability in Bangladesh based on national surveys of Bangladesh Demographic and Health Survey (BDHS) 2007-1994. Total 9703 ever married women are included in the bivariate and multivariate analyses which reveal that age at first birth, age at marriage and marital duration play an important role in influencing marriage to first birth interval positively and thus fecundability negatively. Although fecundability in Bangladesh showed an increasing trend, but it is very low compared to developed and developing countries.
基金supported in part by New Zealand Government core funding for Crown Research Institutes from the Ministry of Business,Innovation,and Employment's Science and Innovation Group.
文摘The nutritional status of an individual can significantly influence its life history traits,including development,growth,reproduction,and survival.In the predatory mite Phytoseiulus persimilis Athias-Henriot(Acari:Phytoseidae),the plasticity of life history traits,such as developmental time and size at maturity,is influenced by the quality and quantity of food.This study aimed to investigate the effects of dietary restriction at different life stages(i.e.,juvenile,early adulthood,and later adulthood)on the lifespan and fecundity of P persimilis.We found that reduced dietary intake during early adulthood resulted in a shorter lifespan for both male and female P persimilis.Furthermore,this study demonstrated a sex-specific response to dietary restriction:it extended the lifespan of males but reduced that of females during later adulthood.Diet restriction during the postovipositional period of females showed the most variable life history trait response.Our results showed that the impact of diet restriction at different life stages can have combined influences on the postovipositional duration of P persimilis,where the individuals receiving diet restriction during immature development and early adulthood had a greater reduction in ovipositional duration as those experiencing diet restriction during late adulthood.In addition,we observed a positive correlation between the lifespan and fecundity of females,with higher prey availability increasing both.The insights obtained from our research contribute to a better understanding of the aging process and dietary requirements of P persimilis,which can facilitate the development of more effective biological control strategies using this predator for spider mites in agriculture.
基金the National Natural Science Foundation of China(30800121).
文摘Mounting evidence suggests that male sperm may be gradually depleted after consecutive matings,resulting in the decline of female reproductive output in insect species.It is predicted that females may employ adaptive strategies to avoid the sperm-depleted males,such as mating multiply with different males and/or discriminating against previously mated males(MMs).Similarly,males may exhibit adaptive behaviors toward females varying in mating status.However,in spiders with males lacking primary copulatory organs and their pedipalps modified to transfer sperm,there are few studies on male mating potential and previous mating experience on their subsequent mate choice.In this study,we used a polyandrous crab spider,Ebrechtella tricuspidata,a sit-and-wait predator with female-biased sex ratio as a model system to ascertain whether 1)male mating experiences influence female reproductive fitness;2)females respond differently to males varying in mating status;and 3)males respond differently to females varying in mating status.Our results showed that female fecundity was independent of male mating experiences,but female fertility markedly declined with the increase of male previous mating experiences in the first eggsac.Counter to our predictions,females preferred to choose and mate with the larger males,regardless of their mating status.In contrast,male mating status influenced their mating preference toward females.Virgin males did not show any preference between virgin and mated females;however,MMs were more likely to prefer the virgin females over the mated ones.Overall,our results indicated that female choice depended primarily on male relative size rather than male mating status,whereas male choice depended on female mating status,Depending on the investigation of reproductive dynamics and mate choice in E.tricuspidata,the study will provide valuable insights into the adaptive behaviors of both males and females exhibiting toward mates varying inmating status.
基金funded by the Key Technology and System Exploration of Quota Fishing,Ministry of Agriculture and Rural Affairs,Fishery Management Fund Project(No.36,2017)the Zhejiang Fishery Resources Survey Special Project(No.HYS-CZ-202314)。
文摘The red tilefish Branchiostegus japonicus is an economically important demersal fish species with high-quality.However,research on its reproductive biology and population structure characteristics is limited.To better understand the reproductive biological features of B.japonicus,a study was conducted on 461 individuals collected from the East China Sea(27°00′-31°00′N,122°30′-127°30′E)from March to December in 2021.This study analyzed the relationship between standard length and the body weight,and detected the sex ratio,length at first sexual maturity,reproductive period,fecundity,and spawning type of this species.The results revealed a power function relationship between body weight(W)and standard length(L)in the samples as the following regression equation:W=0.000014 L^(3.16)(R^(2)=0.956).The sex ratio was close to 1:1(χ^(2)=1.11,P>0.05),and the sex ratio exhibited significant differences according to different standard lengths.Using the logistic equation,we estimated that 50% of B.japonicus individuals had a standard length at sexual maturity of L_(50)=210 mm.By analyzing the monthly variation in the gonadal index and the proportion of each stage of ovarian development in each month,we assumed that the spawning period of B.japonicus occurred from May to November,and the peak spawning period occurred from June to October.The absolute fecundity was 51441±33232 eggs,the relative fecundity at the standard length was(210±117)eggs mm-1,and the relative fecundity relative to body weight was(184±89)eggs g^(-1).The distribution of the egg diameter of B.japonicus had only one obvious peak,indicating the spawning pattern of B.japonicus was once a year.This study updated and enriched the basic biological data of B.japonicus,which is beneficial for obtaining a better understanding of its population dynamics,and promoting the conservation and sustainable utilization of B.japonicus in East China Sea.
基金Supported by the Tianjin Key Laboratory of Marine Resources and Chemistry(Tianjin University of Science&Technology),Tianjin,China(No.202302)the National Natural Science Foundation of China(No.32460154)the China Postdoctoral Science Foundation(No.2023MD734227)。
文摘5-hydroxytryptamine(5-HT)is a biological monoamine neurotransmitter in the central nervous system and gonads of crustaceans to induce gonadal maturation.To better understand the effects of 5-HT and its receptors on reproductive development in Artemia,a 5-HT type 7 receptor gene(5-HT_(7Ar))was identified in parthenogenetic Artemia and characterized.Sequence analysis revealed that the open reading frame of 5-HT_(7Ar) encodes a 414-aa protein.5-HT_(7Ar) showed higher expression in both brain and ovary at early embryo stage,5-HT_(7Ar) could be detected during ovarian development and the highest expression was observed at early embryo stage.Silencing of the 5-HT_(7Ar) in Artemia at early embryo stage decreased significantly the expression level of 5-HT_(7Ar) gene and protein at late oocyte,early embryo,and late embryo stage.Moreover,silencing of the 5-HT_(7Ar) resulted in a decreased fecundity,which corresponds to abnormal oocytes during the embryo development.Artemia tended to produce nauplii after the silencing of 5-HT_(7Ar),indicating that 5-HT_(7Ar) may also involve in the determination of its reproduction mode.The findings of this study provide an insight into the regulation of reproductive development in Artemia and the function of 5-HT_(7Ar).
基金supported by the National Key R&D Program of China (No.2019YFD1100501)。
文摘17β-Estradiol(E2)has been widely detected in natural water and treatment with E2 induces potential endocrine disrupting effects in fish.However,effects on fish fecundity and steroid system after treatment with environmentally relevant concentrations of E2 for the full sexual maturation cycle remain unclear.In this study,zebrafish were treatment with 0,10 or100 ng/L E2 from embryo to adult stage,and effects on gonadal development and differentiation,steroid hormone levels,transcription of genes associated with the hypothalamic-pituitary-gonadal-liver(HPG)axis in adults and fertilization rate of offspring were assessed.The results showed that treatment with E2 lead to increased number of feminization in zebrafish.In females,E2 decreased cumulative amount of spawning and inhibited the maturation of oocyte.In males,E2 inhibited the maturation and motility of sperm,as well as decreased the movement speed of sperm.These adverse effects on sperm might be responsible for the reduced fertilization observed in offspring.In addition,treatment with E2 changed the levels of steroid hormones in zebrafish gonad and altered the transcriptional levels of genes associated with HPG axis,which is responsible for the regulation of germ cells maturation and gonadal development in zebrafish.Overall,these results suggested that treatment with environmentally relevant concentrations of E2 for the full sexual maturity cycle resulted in adverse effects on reproduction in zebrafish.
基金Supported by the Technology Innovation Development Program of Yantai(No.2020MSGY055)。
文摘To understand the reproductive biology of Hemitripterus villosus in the Bohai Strait,and fill the key knowledge gap in verifying reproductive seasonality and documenting gonadotropin dependent reproductive cycle of this species,a year-round detail study was conducted for the first time.In total,263 individuals were randomly sampled off the coasts of the Bohai Strait.Results show that and the overall female-to-male ratio(1.35:1)did not differ significantly from the 1:1 sex ratio.The length and weight relationship for females and males were regressed,depicting an isometric growth for both sexes.Four reproductive phases of the complete gonadotropin dependent reproductive cycle in both sexes were identified.The monthly variations in the gonadosomatic and hepatosomatic indexes for both sexes further indicated that this species spawns a single batch of eggs per year and the peak spawning period is from October to December.The average diameter of eggs ranged from 2.10 to 3.57 mm.The length at first sexual maturity was 224.87 mm for females and 241.26 mm for males.Significant positive relationships between absolute fecundity and fish size,and also gonadal weight were observed.H.villosus from the Bohai Strait exhibited smaller body size,smaller egg diameter,lower gonadosomatic index,lower absolute fecundity,and higher population extinction risk than the other populations’studied previously.Our findings contribute to understanding the status of this isolated westernmost population,and we emphasize that more efficient protection measures for the species and control measures are urgently required to improve the coastal environment in the Bohai Strait.
基金supported by grants from the Special Foundation for Basic Work of the Science and Technology Ministry of China (2022FY100500-2)National Natural Science Foundation of China (31470471)+2 种基金Hainan Key Program of Science and Technology (ZDXM20110008)Hainan Specially Supporting Discipline of ZoologyWenzhou Ecological Park Research Project。
文摘We studied sexual dimorphism in body size and shape and female reproductive characteristics in the Hainan Water Skink(Tropidophorus hainanus)from Hainan,South China.In our sample the largest female and male were 61.1 and 55.2 mm snout-vent length(SVL),respectively.The mean SVL was larger in adult females(52.0 mm)than in adult males(48.3 mm).Juveniles were sexually dimorphic in head length but not in other examined morphological variables.Adult males were longer in head length and shorter in abdomen length and fore-limb length than adult females of the same SVL.Ontogenetic shifts in sexual dimorphism in body shape were evident,as revealed by the fact that morphological differences between the sexes were more pronounced in adults than in juveniles.Females produced a single litter of 3–6 offspring per season from early August to early September.Litter size,litter mass and offspring(neonate)mass were positively related to female SVL.Neonate mass was independent of relative fecundity.From the above findings we draw three main conclusions.First,females are the larger sex in T.hainanus,and sexual dimorphism in body shape is more pronounced in adults than in juveniles.Second,larger female T.hainanus produce more and larger offspring and thus heavier litters than smaller ones.Third,the offspring size-number trade-off does is not evident in T.hainanus.
基金Supported by National Science Foundation of China(31171855)Special R&D Fund for Plant Epidemic Prevention and Quarantine in Guangdong Province(Yuenongji201190)~~
文摘[Objective] The aim was to study on the effect of hosts on development and reproduction of mealybug （Phenacoccus solenopsis Tinsley）. [Method] Observation was conducted on developmental durations and fecundity of Phenacoccus solenopsis Tinsley fed on Gossypium spp., Nicotiana tabacum, Solanum tuberosum L and Hibiscus rosa-sinensis. [Result] There were differences among all durations, generation durations and fecundities of the mealybug adult females. Specifically, the generation durations on cotton （Gossypium spp.）, tobacco（ Nicotiana tabacum）, potato （Solanum tuberosum L） and Hibiscus rosa-sinensis were 30.2, 28.2, 37.3, and 27.7 d, and the fecundities per female were 626.0, 417.2, 552.5, and 183.2 ind., respectively. [Conclusion] The mealybug would have strong pontential in population growth when fed on cotton, tobacco and potato.
文摘The World Health Organization （WHO） has extensively revised its manual for semen analysis, and seeks to provide reference limits for semen quality parameters. This raises the question of what is meant by ＇normal＇ （excluding the use of this term to denote a Gaussian distribution）. It could be taken in a purely statistical sense, using a biologically arbitrary cut-off point to denote an abnormal level, typically the extreme 5 percent of the population. Alternatively, ＇normal＇ could be defined according to the biological concept of normality and abnormality, in terms of the point at which biological function becomes impaired. Either of these can be used in descriptive epidemiology, for example, to study trends, but in the case of fertility, both semen quality and functional fertility （time to pregnancy） are continuous variables with no clear threshold. The WHO manual uses the biological meaning of normal, in that it provides the semen parameter distributions for men who have recently fathered pregnancies that took 12 months or less to conceive. However, what is really needed is the same information the other way around： given a particular semen test result, what should be expected in terms of ability to conceive, and how long it is likely to take. In considering epidemiological research, the focus has been mainly on internal comparisons, rather than reference limits, but it would be beneficial if more attention were paid to the absolute levels and to what these mean in terms of function--in other words, if the data were better calibrated biologically.
文摘Several recent studies have shown that the fecundity of a man decreases progressively with sperm concentrations below 40 million spermatozoa per mL. Therefore, it is unfortunate that the new World Health Organization guidelines for semen analysis recommend lowering the lower cutoff value for normal sperm concentration from 20 to 15 million spermatozoa per mL. As a result large groups of subfertile men across the world may not receive appropriate andrological help in the future.
基金supported by the earmarked fund for China Agriculture Research System(CARS-15-19)the Central Public-interest Scientific Institution Basal Research Fund,China(Y2019YJ06)。
文摘In December 11,2018,the fall armyworm(FAW),Spodoptera frugiperda invaded China and has since impacted local maize,sorghum and other crops.Here,we draw on laboratory experiments to show how different host crops(i.e.,maize,sorghum,wheat and rice)and artificial diet affect larval growth and adult reproduction of one local FAW strain.Larval diet affected development duration,pupation rate,survival and emergence rate of pupae,and S.frugiperda adult fecundity.FAW attained the slowest larval development(19.4 days)on sorghum and the fastest(14.1 days)on artificial diet,with larvae attaining 99.6%survival on the latter food item.On rice,FAW larvae attained survival rate of 0.4%and were unable to pupate successfully.Pupation rate and pupal survival varied substantially between artificial diet and live plantlets at different phenological stages.Pupal weight was the highest(0.26 g)on artificial diet and the lowest(0.14 g)on sorghum,while FAW females reached the highest fecundity(699.7 eggs/female)on 2-leaf stage maize.Egg hatching rate equaled 93.6%on 4-or 5-leaf stage maize and 36.6%on artificial diet.FAW intrinsic rate of natural increase and the finite rate of increase varied between larval diets,reflecting how young maize leaves are the most suitable diet.Our findings can help to refine laboratory rearing protocols,devise population forecasting models or guide the deployment of‘area-wide’integrated pest management(IPM)modules in FAW-invaded areas of China and other Asian countries.
基金supported by the National Key R&D Program of China(2019YFD0300102)the earmarked fund for China Agriculture Research System(CARS-15-19)the Central Public-interest Scientific Institution Basal Research Fund,China(CAAS-ZDRW202007)。
文摘The fall armyworm(FAW),Spodoptera frugiperda,is a newly invasive,widespread agricultural pest in China.Understanding the suitability of the main field crops in Chinese agricultural system as host for this polyphagous herbivore is especially important for making control strategy.Here,after FAWs were fed three important oil-bearing crops(oilseed rape,soybean and sunflower)planted in China and resultant population parameters were compared using the age-stage,two-sex life table method,survival of larvae on soybean was significantly lower than that on oilseed rape and sunflower.Developmental duration of larvae on soybean was also the longest(23.3 days).The highest pupation rate was recorded on sunflower.The highest pupal mass(0.19 g)was attained on oilseed rape,significantly higher than on the other host plants;the lowest mass was on soybean(0.15 g).On soybean,oilseed rape and sunflower,respectively,the average generation period was 42.21,39.10 and 40.44 d;the intrinsic rate of increase(r)was 0.0844,0.1041 and 0.1134;the finite rate of increase(λ)was 1.0881,1.1098 and 1.1202.While the most suitable host plant overall was sunflower,S.frugiperda completed development and increased its population on all three host plants.Thus,soybean,oilseed rape and sunflower were all suitable for FAW,and population monitoring and management of FAW in these crops should be increased.
基金by National Basic Research Program of China(2009CB119200)Anhui Provincial Natural Science Foundation(090413080)Natural Science Foundation of Anhui Education Bureau(KJ2009A110,KJ2008B211)
文摘Breeding strategies of Acrossocheilus fasciatus were studied from 592 specimens collected monthly during May 2007 and April 2008 in the Puxi Stream of the Huangshan Mountain. Sex ratio of the studied population was 0.90 ： 1 （ ♀ ： ♂ ）, not significantly different from 1 ： 1. Both sexes reached their first sexual maturity at age 2 （the second calendar year of their birth）. Fifty percent of females and males reached maturity at a total length of 69.75 mm and 69.36 mm respectively, and the minimum total length was 61.54 mm and 58.96 mm, respectively. Based on the monthly changes in gonado-somatic index and egg- development process, the breeding season of the population was from May to August, with one obvious interval （in June） occurring in the breeding activity for the females. The nonsynchronous development of oocytes observed in mature ovaries indicated that A. fasciatus is a batch spawner. Absolute fecundity of A. fasciatus ranged from 308 to 2002 eggs with a mean of 857 eggs, increased significantly with total length, and was significantly different among three age groups. Relative fecundity ranged from 38.63 to 71.70 egg/g with a mean of 53.29 egg/g, and was not significantly different among the three age groups. It was suggested that these reproductive characteristics were adaptive strategies for A. fasciatus to acclimatize to lotic water where environmental factors were unstable but predictable [ Current Zoology 55 （5） ： 350 - 356, 2009].
文摘Although amphioxus is widespread in temperate and tropical seas,its population is diminishing be-cause of environmental pollution.To keep the population of this evolutionarily important animal fromdiminishing,study on its reproduction and development is necessary.The main findings in this study onthe spawning and fecundity of the amphioxus reared in laboratory and its larval development are as fol-lows.1.Water temperature markedly affected the spawning.It spawned only when water temperature reached 21℃.2.Spawning of the amphioxus in laboratory was markedly extended.Initially,the amphioxus spawned at about 7:00 PM,but spawning time was postponed as spawning days went on.3.The number of eggs produced by a female ranged from 1400 to 12800,average of 5800.This al-so represents the fecundity of the amphioxus because it shedded all eggs within the ovary at a time.4.During the first few months of life of the amphioxus,its growth rate changed seasonally.Thegrowth rate in summer and fall was greater than that
基金the Program for New Century Excellent Talents in Chinese University (No.NCET-04-0914)the National Natural Science Foundation of China (No.30570281)+1 种基金the Yunnan Natural Science Foundation (No.2002C0001Z,2005C0004Q)the Natural Science Foundation of Ministry of Education of Yuannan (No.08Z0028)
文摘A series of tests (lethal,sublethal,and behavioral) on earthworms were conducted as an eco-assessment of pesticides.In this study,the toxicity of cypermethrin-contaminating soil on adult and juvenile earthworms was assessed.Beside the acute and chronic tests,an avoidance response test was carried out.It was shown that the all-round toxicity from cypermethrin was weak on adult earthworms.Compared with adult earthworms,the toxicity of juvenile earthworms from cypermethrin especially chronic toxicity increased...
基金Project supported by the National Basic Research Program(973)of China(No.2006CB102002)the Pilot Project of Knowledge Innovation Program of Chinese Academy of Sciences(No.KSCX2-YW-N-006)National Natural Science Foundation of China(No.30571253,30621003)
文摘The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera （Htibner）, fed on cotton bolls grown under elevated CO2 （double-ambient vs. ambient） in open-top chambers were examined. Significant decreases in protein, total amino acid, water and nitrogen content and increases in free fatty acid were observed in cotton bolls. Changes in quality of cotton bolls affected the growth, development and food utilization of H. armigera. Significantly longer larval development duration in three successive generations and lower pupal weight of the second and third generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower fecundity was also found in successive three generations of H. armigera fed on cotton bolls grown under elevated CO2. The consumption per larva occurred significant increase in successive three generations and frass per larva were also significantly increased during the second and third generations under elevated CO2. Significantly lower relative growth rate, efficiency of conversion of ingested food and significant higher relative consumption rate in successive three generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower potential female fecundity, larval numbers and population consumption were found in the second and third generations of cotton bollworm fed on cotton bolls grown under elevated CO2. The integrative effect of higher larval mortality rate and lower adult fecundity resulted in significant decreases in potential population consumption in the latter two generations. The results show that elevated CO2 adversely affects cotton bolls quality, which indicates the potential population dynamics and potential population consumption of cotton bollworm will alleviate the harm to the plants in the future rising CO2 atmosphere.
基金Acknowledgments This study was supported by grants from the National Science Foundation of China （Project No. 30670281） and the Zhejiang Provincial Department of Education （Project No. Y200908723）. We thank Lai-Gao Luo, Long-Hui Lin, Yan-Fu Qu, Xi-Dong Zhang, Hong Li and Hong-Xia Liu for their help during the research.
文摘We used the Chinese skink Eumeces chinensis as a model animal to study the effects of tail loss on reproductive in- vestment and offspring traits. A total of 147 wild-captured adult females were divided into four groups according to their tail con- ditions. Tail breaks occurred most frequently in the proximal portion of the tail and least frequently in the distal portion, with the middle portion in between. This finding suggests that tail breaks occurring in nature often entails substantial energetic costs in E. chinensis where the tail is a major site of energy storage. The proportion of females that laid eggs was higher in females with in- tact or completely regenerated tails than in those with broken tails. Following whole-tail autotomy, the clutch size was reduced by 17%, and the clutch mass was reduced by 14%. Females undergoing substantial tail autotomy reduced reproductive investment, and they did so by reducing the number but not the size of eggs produced. None of the egg and hatchling traits was affected by tail loss. Comparing our data with those reported for other oviparous and viviparous skinks allows us to draw two general conclu- sions： one is that fecundity （clutch or litter size） is affected by tail loss in all species so far studied, whereas offspring size is af- fected by tail loss in some species, but not in others; the other is that the reduction in fecundity following tail loss is more evident in species lacking abdominal fat bodies
基金supported by the earmarked fund of China Agriculture Research System(CARS-15-19)the Central Public-interest Scientific Institution Basal Research Fund,China(Y2019YJ06)。
文摘Floral resources,such as carbohydrate-rich nectar or pollen,can bolster fitness and raise reproductive output of adult lepidopterans.Here,we used laboratory experiments to assess how those plant-derived foods impact adult fecundity,reproductive physiology and flight performance of an invasive strain of the fall armyworm,Spodoptera frugiperda(FAW;Lepidoptera:Noctuidae)in China.More specifically,supplementary feeding on bee pollen and honey enhanced FAW flight duration,testis size,ovarian development,longevity and adult fecundity.FAW adults attained the longest pre-oviposition(10.8 days)and oviposition period(6.8 days)and longevity(19.2 days)on 5%acacia honey.Upon access to 2.5%acacia honey and 2.5‰pine pollen,S.frugiperda attained the highest mating rate(79.7%),fecundity(644.9 eggs/female)and egg hatching rate(82.3%).Feeding on honey further delayed decay of male testes,while ovarian development was enhanced when female moths were allowed access to 2.5%honey and 2.5‰pine pollen.Upon feeding on 5%honey solution,S.frugiperda engaged in flight over the longest duration(9.5 h),distance(29.9 km)and speed(3.1 km h-1).Honey had a comparatively greater effect on the above parameters than pollen.Our findings help decipher FAW invasion patterns and population dynamics,facilitate the development of nutritional attractants,and contribute to integrated pest management of this newly-invasive pest in eastern Asia.
文摘We examined sexual size dimorphism （SSD）, mating pattem, fertilization efficiency and female reproductive traits in two bufonid toads （Bufo gargarizans and Duttaphrynus melanostictus） to test the idea that importance of male body size for egg fertilization success depends on the mating pattern. Female-biased SSD was evident only in D. melanostictus. Female B. gar- garizans laid fewer larger eggs nearly three months earlier than did female D. melanostictus. Fertilization efficieneies on average were higher in B. gargarizans （95%） than in D. melanostictus （91%）. Though differing in the degree of SSD, body size, breeding season, clutch size, egg size and fertilization efficiency, the two toads were similar in four aspects： （1） both showed size-assortative mating; （2） females did not tradeoff egg size against egg number; （3） male size, clutch size and clutch dry mass were greater in male-larger than in female-larger pairs after accounting for female snout-vent length （SVL）; and （4） the ratio of male to female SVL did not affect fertilization efficiency. Our data show that： （1） a female preference for large males is likely not important in terms of egg fertilization success; （2） a male preference for large females is likely important because larger females are more fecund; and （3） size-assortative mating arises from a male preference for large females. Our study demonstrates that male size is not always important for egg fertilization success in anurans that show size-assortative mating.
