Age-dependent changes in the ratio of (R)- and (S)-2-butanol released by virgin females of Dasylepida ishigakiensis (Coleoptera: Scarabaeidae)

AbstractThe females of the white grub beetle, Dasylepida ishigakiensis, release two enantiomers of 2-butanol, (R)-2-butanol and (S)-2-butanol. The ratio describing the relative proportions of these two enantiomers (R/S ratio) has not yet been investigated. (R)-2-Butanol has been shown to attract males in laboratory and field experiments, whereas (S)-2-butanol tends to inhibit them. To determine the R/S ratio of the 2-butanol emitted by virgin females, we collected 2-butanol from young (53 days old), mature (63 days old) and old females (73 days old) using water, extracted with an SPME fibre and subsequently injected into GC-MS. The major component of the 2-butanol emitted by the young females was (R)-2-butanol, but as the females aged, the component ratio favoured (S)-2-butanol. Young females released an 80:20 mixture of (R)- and (S)-2-butanol, whereas old females released a 45:55 mixture. The EAG response of male antennae to a 50:50 ratio (racemic mixture) showed a similar dose-response curve to that of (R)-2-butanol. The male orientation responses to (R)-2-butanol decreased when the relative proportion of (S)-2-butanol increased. An inhibitory and/or masking effect of (S)-2-butanol on male orientation behaviour was also observed in the flight tunnel assay. These results suggest that males are more strongly attracted to young females than to old females. We also discuss the possibility of using 2-butanol isomers as a control or monitoring agent for this insect.

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Male white grub beetles prefer the pheromone composition of young females in the field

Bulletin of Entomological Research ◽

10.1017/s0007485316000432 ◽

2016 ◽

Vol 106 (5) ◽

pp. 679-684 ◽

Cited By ~ 1

Author(s):

N. Fujiwara-Tsujii ◽

H. Yasui ◽

S. Wakamura ◽

A. Nagayama ◽

N. Arakaki

Keyword(s):

Sex Pheromones ◽

Flight Tunnel ◽

White Grub ◽

Young Males ◽

Young Females ◽

Dasylepida Ishigakiensis ◽

Female Pheromone ◽

Pheromone Composition ◽

Older Males ◽

Qualitative Changes

AbstractFemales of the white grub beetle, Dasylepida ishigakiensis, release both (R)- and (S)-2-butanol as sex pheromones, but the males are only attracted to (R)-2-butanol. In laboratory-reared females, the proportion of the (R)-isomer decreased significantly as their calling opportunities increased and as they aged. We examined whether such qualitative changes also occur in field populations. We collected virgin females from the field and then trapped and analysed the volatiles emitted during their first and second callings. The ratio of (R)- to (S)-2-butanol (R/S) was 78:22 at the first calling, but shifted to 39:61 at the second calling. While investigating the composition of the female pheromones, the question arose as to whether the male preferences change in response to the shift in female pheromone composition. To answer this question, we observed the behaviour of young and old males in response to various R/S ratios as lures in the laboratory and in the field. In the flight tunnel assay of laboratory-reared individuals, young males touched female models with a 9:1 R/S ratio lure less than those with pure (R)-2-butanol; however, older males touched the two groups with equivalent frequency. In the field trap test, older males were much more attracted to (R)-2-butanol-scented lures. When we tested using lures with the same amount of (R)-2-butanol but added different amounts of the (S)-isomer, we found that increased levels of (S)-2-butanol resulted in lower attractiveness to males. (S)-2-butanol was confirmed to have an inhibitive activity in the attractiveness of (R)-2-butanol.

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Old maids have more appeal: effects of age and pheromone source on mate attraction in an orb-web spider

PeerJ ◽

10.7717/peerj.1877 ◽

2016 ◽

Vol 4 ◽

pp. e1877 ◽

Cited By ~ 10

Author(s):

Anna-Lena Cory ◽

Jutta M. Schneider

Keyword(s):

Field Experiments ◽

Time Frame ◽

Pheromone Production ◽

Mate Attraction ◽

Young Females ◽

Web Spider ◽

Pheromone Emission ◽

Orb Web ◽

Old Females ◽

Number Of Males

Background.In many insects and spider species, females attract males with volatile sex pheromones, but we know surprisingly little about the costs and benefits of female pheromone emission. Here, we test the hypothesis that mate attraction by females is dynamic and strategic in the sense that investment in mate attraction is matched to the needs of the female. We use the orb-web spiderArgiope bruennichiin which females risk the production of unfertilised egg clutches if they do not receive a copulation within a certain time-frame.Methods.We designed field experiments to compare mate attraction by recently matured (young) females with females close to oviposition (old). In addition, we experimentally separated the potential sources of pheromone transmission, namely the female body and the web silk.Results.In accordance with the hypothesis of strategic pheromone production, the probability of mate attraction and the number of males attracted differed between age classes. While the bodies and webs of young females were hardly found by males, the majority of old females attracted up to two males within two hours. Old females not only increased pheromone emission from their bodies but also from their webs. Capture webs alone spun by old females were significantly more efficient in attracting males than webs of younger females.Discussion.Our results suggest that females modulate their investment in signalling according to the risk of remaining unmated and that they thereby economize on the costs associated with pheromone production and emission.

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Mating disruption by a synthetic sex pheromone in the white grub beetle Dasylepida ishigakiensis (Coleoptera: Scarabaeidae) in the laboratory and sugarcane fields

Bulletin of Entomological Research ◽

10.1017/s0007485311000502 ◽

2011 ◽

Vol 102 (2) ◽

pp. 157-164 ◽

Cited By ~ 10

Author(s):

H. Yasui ◽

S. Wakamura ◽

N. Fujiwara-Tsujii ◽

N. Arakaki ◽

A. Nagayama ◽

...

Keyword(s):

Sex Pheromone ◽

Mating Disruption ◽

Sexual Communication ◽

Substantial Reduction ◽

Flight Tunnel ◽

White Grub ◽

Dasylepida Ishigakiensis ◽

Short Period ◽

Synthetic Sex Pheromone ◽

Almost All

AbstractA serious sugarcane pest, Dasylepida ishigakiensis, remains in the soil during most of its life cycle except for a short period for mating. Mating disruption by an artificial release of the sex pheromone (R)-2-butanol (R2B), therefore, may be a feasible method to control this pest. We examined the effects of artificial release of R2B and its related compounds, (S)-2-butanol (S2B) and the racemic 2-butanol (rac-2B), on the mating success of this beetle both in the laboratory and in the field. In flight tunnel experiments, almost all males orientated towards a R2B-releasing source and 40% of them landed on the source. When the atmosphere was permeated with R2B, the frequency of males landing on the model was significantly reduced. Both rac-2B and S2B were less effective, but substantial reduction in landing success by males was achieved at higher rac-2B concentrations. R2B released from polyethylene dispensers in sugarcane plots greatly reduced not only the proportion of females mated with males but also the number of males caught by R2B-baited traps, indicating that male mate-searching behaviour was strongly affected by the released R2B. Similar inhibitory effects on male behaviour were also observed when tube- or rope-type dispensers released high rac-2B concentrations in the field. These results indicate that it would be highly possible to control D. ishigakiensis through the disruption of the sexual communication by releasing either synthetic R2B or rac-2B.

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Genetic divergence among populations of the white grub beetle, Dasylepida ishigakiensis (Coleoptera: Scarabaeidae), distributed in the southern part of the Ryukyu Islands of Japan, detected from mitochondrial DNA sequences

Applied Entomology and Zoology ◽

10.1303/aez.2008.287 ◽

2008 ◽

Vol 43 (2) ◽

pp. 287-292 ◽

Cited By ~ 6

Author(s):

Masahiko Muraji ◽

Yoshio Hirai ◽

Toshiharu Akino ◽

Sadao Wakamura ◽

Norio Arakaki

Keyword(s):

Mitochondrial Dna ◽

Dna Sequences ◽

Genetic Divergence ◽

Ryukyu Islands ◽

White Grub ◽

Dasylepida Ishigakiensis ◽

The Ryukyu Islands

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Gamma irradiation used on adult Tetranychus urticae Koch as a quarantine treatment

Journal of Plant Protection Research ◽

10.2478/jppr-2014-0024 ◽

2014 ◽

Vol 54 (2) ◽

pp. 150-155 ◽

Cited By ~ 3

Author(s):

Shiva Osouli ◽

Karim Haddad Irani Nejad ◽

Farhoud Ziaie ◽

Mohammad Moghaddam

Keyword(s):

Gamma Radiation ◽

Gamma Irradiation ◽

Dose Rate ◽

Tetranychus Urticae ◽

Linear Trend ◽

Young Females ◽

Dose Rates ◽

Adult Females ◽

Tetranychus Urticae Koch ◽

Old Females

Abstract The effect of gamma radiation with 0, 200, 250, 300, 350, 400, and 450 Gy intensities on the longevity, total number of eggs, and the percent of hatched eggs laid by irradiated females of Tetranychus urticae Koch (Tetranychidae) was evaluated. Two different groups (0–24 h old and 48–72 h old) of adult females were irradiated. The results showed that 350 and 300 Gy doses significantly reduced the longevity of the 0–24 h old females and the 48–72 h old females. The younger females were more tolerant at lower dose rates than the older females. There was a quadratic relationship between dose rates and young females, while it was linear in older females. The total number of eggs laid by females of both ages was significantly reduced with a linear trend by 250 Gy irradiation. The eggs laid by females of both the 0–24 h olds and the 48–72 h olds lost their hatchability when the dose rate was 350 Gy. It was concluded, that applying a dose rate of 320 Gy on one of the mates (male or female) before mating, or a 300 Gy on both of them, would be sufficient to cause sterility in adult mites.

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Efficacy of entomopathogenic nematodes for the control of white grub, Anomala corpulenta Motschulsky, in laboratory and field

Nematology ◽

10.1163/15685411-bja10015 ◽

2020 ◽

Vol 22 (10) ◽

pp. 1111-1120

Author(s):

Wenxiu Guo ◽

Guoyu Zhao ◽

Congli Wang ◽

Xianhong Zhou ◽

Yifan Zhai ◽

...

Keyword(s):

Entomopathogenic Nematodes ◽

Field Experiments ◽

Application Rate ◽

High Rate ◽

White Grub ◽

White Grubs ◽

Yield Increase ◽

Significant Difference ◽

Peanut Production ◽

Environmentally Friendly Method

Summary Anomala corpulenta is one of the major white grubs that cause serious damages in peanut production. To develop an environmentally friendly method to control A. corpulenta larvae, the efficacy of species of entomopathogenic nematodes (EPN), application rate and larval stage against A. corpulenta were determined. Results showed that Steinernema longicaudum X-7 and S. glaseri B-4-1 were the most virulent species, which caused 77.8 and 84.4% corrected mortalities of the 2nd instar larvae at 25°C 14 days after treatments. Corrected mortalities of A. corpulenta caused by EPN were significantly affected by EPN application rate. A decrease but no significant difference in susceptibility from the 2nd to the 3rd instar was observed for the test EPN species S. longicaudum, S. glaseri and Heterorhabditis bacteriophora. The field experiments indicated that S. longicaudum and S. glaseri applied at a relatively high rate (⩾5.0 × 103 infective juveniles (IJ) plant−1, i.e., 7.5 × 108 IJ ha−1) were able to provide not only control efficacy against A. corpulenta with ⩾92.7% reduction of larvae and ⩽5.06% of damaged pods, and the peanut yield increase was as good as phoxim, but also gave better control persistency compared to phoxim. Our findings indicated that EPN could be an effective strategy for the management of A. corpulenta in peanut fields.

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Vertical distribution of female adults and larval offspring of the white grub Dasylepida ishigakiensis (Coleoptera: Scarabaeidae) in the soil of a sugarcane field on Miyako Island, Okinawa

Applied Entomology and Zoology ◽

10.1007/s13355-010-0021-y ◽

2011 ◽

Vol 46 (2) ◽

pp. 171-176 ◽

Cited By ~ 2

Author(s):

Akira Oyafuso ◽

Moriya Ota ◽

Masato Ishimine ◽

Norio Arakaki

Keyword(s):

Vertical Distribution ◽

White Grub ◽

Sugarcane Field ◽

Dasylepida Ishigakiensis

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252 EFFECTS OF IN VITRO MATURATION AND AGE ON OOCYTE METAPHASE SPINDLE INTEGRITY AND CHROMOSOME SEGREGATION IN THE RHESUS MONKEY

Reproduction Fertility and Development ◽

10.1071/rdv21n1ab252 ◽

2009 ◽

Vol 21 (1) ◽

pp. 224

Author(s):

S. M. Nichols ◽

J. A. Gonzalez-Martinez ◽

B. D. Bavister

Keyword(s):

Rhesus Monkey ◽

Chromosome Segregation ◽

Abnormal Chromosome ◽

Reliable Technique ◽

Immature Oocytes ◽

Young Females ◽

Significant Difference ◽

Chromosome Alignment ◽

Old Females ◽

Metaphase Ii Oocytes

Oocyte IVM offers tremendous potential for the treatment of infertility by reducing the costs, risks, and side effects associated with ovarian stimulation. Although normal offspring have been produced using IVM/IVF technology in humans and monkeys, IVM is far from being a reliable technique for the production of developmentally competent oocytes in primates. This study examined oocyte karyotype and spindle integrity in rhesus monkey oocytes, and attempted to correlate anomalies with IVM and age of oocyte donors. Each of 14 females (ages 6 to 22 years) underwent both regimen A (FSH + hCG) and regimen B (FSH only) stimulation cycles at least once over the study period to facilitate collection of both mature and immature oocytes. Immature oocytes from regimens A and B underwent IVM to produce metaphase II oocytes. Metaphase II oocytes from each collection cycle cohort were fixed for either karyotype or metaphase spindle analysis. Statistical analysis of aneuploidy rates and spindle aberrations was performed using 2 × 2 G tests. Karyotype analysis revealed a significantly lower rate of aneuploidy in in vivo-matured (IVO) oocytes (6.0%) compared with IVM oocytes from regimen B (19.8%). Factoring age into these analyses revealed a significant difference in aneuploidy rate between IVO oocytes from young females (4.7%) and regimen B IVM oocytes from old females (25.0%; P < 0.05). Confocal analysis demonstrated a significant increase in metaphase spindle anomalies in IVM oocytes compared with IVO oocytes, which could be attributed to a significant increase in the rate of abnormal chromosome alignment on the metaphase spindle in IVM oocytes originating from either stimulation regimen: 7.0% in IVO oocytes v. 27.9% (regimen A) and 32.6% (regimen B) in IVM oocytes (P < 0.05). When donor female age was considered, regimen B IVM oocytes from old females displayed abnormal chromosome alignment on the spindle equator at a significantly higher rate than oocytes of any other maturation condition or age group (P < 0.05). In addition, IVO oocytes from young females showed this anomaly at a significantly lower rate than regimen B IVM oocytes from the same young females. We conclude that IVM can induce meiotic anomalies in the macaque oocyte, especially those obtained from older females. The results from this study provide possible explanations for the reported reduction in developmental competence of IVM v. IVO primate oocytes. This study provides information on the nuclear aspects of IVM, namely, the effect of maturation conditions and age on incidences of abnormal chromosome segregation during meiosis I and abnormal chromosome congression during meiosis II, data that may be helpful for determining optimal IVM culture conditions.

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