scholarly journals Non-canonical function of theSex-lethalgene controls the protogyny phenotype inDrosophila melanogaster

2021 ◽  
Author(s):  
Ki-Hyeon Seong ◽  
Siu Kang
Keyword(s):  
Dosage Compensation ◽  
Sexual Maturation ◽  
Fruit Fly ◽  
Fruit Flies ◽  
Activity Monitoring ◽  
Whole Body ◽  
Human Beings ◽  
Canonical Function ◽  
Individual Activity ◽  
Time Points

AbstractMany animal species exhibit sex differences in the time period prior to reaching sexual maturity. However, the underlying mechanism for such biased maturation remains poorly understood. Females of the fruit flyDrosophila melanogastereclose 4 h faster on average than males, owing to differences in the pupal period between the sexes; this characteristic is referred to as the protogyny phenotype. Here, we aimed to elucidate the mechanism underlying the protogyny phenotype in the fruit fly using our newly developedDrosophilaIndividual Activity Monitoring and Detecting System (DIAMonDS), which can continuously detect the precise timing of both pupariation and eclosion of individual flies. Via this system, following the laying of eggs, we detected the precise time points of pupariation and eclosion of a large number of individual flies simultaneously and succeeded in identifying the tiny differences in pupal duration between females and males. We first explored the role of physiological sex by establishing transgender flies via knockdown of the sex-determination gene,transformer(tra) and its co-factortra2, which retained the protogyny phenotype. In addition, disruption of dosage compensation bymale-specific lethal(msl-2) knockdown did not affect the protogyny phenotype. TheDrosophilamaster sex switch gene—Sxlpromotes female differentiation viatraand turns off male dosage compensation through the repression ofmsl-2.However, we observed that stage-specific whole-body knockdown and mutation ofSxlinduced disturbance of the protogyny phenotype. These results suggest that an additional, non-canonical function ofSxlinvolves establishing the protogyny phenotype inD. melanogaster.Author summaryA wide variety of animals show differences in time points of sexual maturation between sexes. For example, in many mammals, including human beings, females mature faster than males. This maturation often takes several months or years, and precisely detecting the time point of maturation is challenging, because of the continuity of growth, especially in mammals. Moreover, the reason behind the difference in sexual maturation time points between sexes is not fully understood. The fruit flyDrosophila—a model organism—also shows biased maturation between the sexes, with females emerging 4 h faster than males (a characteristic known as the protogyny phenotype). To understand the mechanism underlying the protogyny phenotype, we used our newly developed system,DrosophilaIndividual Activity Monitoring and Detecting System (DIAMonDS), to detect the precise eclosion point in individual fruit flies. Surprisingly, our analysis of transgender flies obtained by knockdown and overexpression techniques indicated that a physiological gender might not be necessary requirement for protogyny and that a non-canonical novel function of the fruit fly master sex switch gene,Sxl, regulates protogyny in fruit flies.

scholarly journals Caffeine as a promotor of sexual development in sterile Queensland fruit fly males

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Saleh Mohammad Adnan ◽  
Iffat Farhana ◽  
Soo Jean Park ◽  
Polychronis Rempoulakis ◽  
Phillip W. Taylor
Keyword(s):  
Sexual Maturation ◽  
Market Access ◽  
Fruit Fly ◽  
Fruit Flies ◽  
Environmentally Benign ◽  
Management Technique ◽  
Sexually Active ◽  
Instant Coffee ◽  
Positive Effects ◽  
High Doses

Abstract Sterile insect technique (SIT) is an environmentally benign pest management technique that involves releasing millions of sterile insects to suppress reproduction of pest populations. Many fruit flies, including Queensland fruit fly (Bactrocera tryoni Froggatt, ‘Q-fly’), have long adult maturation periods such that pre-maturation mortality can greatly reduce abundance of sexually active sterile males and impede SIT efficacy. Q-fly is the most difficult and costly challenge to market access for Australia’s horticulture industries, and has been targeted for intensive use of SIT program. We here demonstrate potential of pre-release caffeine supplements as a novel means to accelerate sexual maturation in male Q-fly. In mating trials, analytical caffeine was very effective at accelerating sexual maturation, while no positive effects of caffeine-containing instant coffee or guarana supplements were detected. In parallel, development of testes and ejaculatory apodemes was accelerated in males provided analytical caffeine but not instant coffee or guarana. High doses of guarana and instant coffee reduced longevity while even the highest doses of analytical caffeine did not affect longevity. Pre-release caffeine supplements promote sexual maturation in Q-flies, and similar benefits are expected in other fruit flies having long adult maturation periods.

Linking mango infestation by fruit flies to fruit maturity and fly pressure: A prerequisite to improve fruit fly damage management via harvest timing optimization

2021 ◽  
Vol 146 ◽  
pp. 105663
Author(s):  
Isabelle Grechi ◽  
Anne-Laure Preterre ◽  
Aude Caillat ◽  
Frédéric Chiroleu ◽  
Alain Ratnadass
Keyword(s):  
Fruit Fly ◽  
Fruit Flies ◽  
Timing Optimization ◽  
Fruit Maturity ◽  
Harvest Timing

scholarly journals Host Suitability Index for Polyphagous Tephritid Fruit Flies

2021 ◽  
Author(s):  
Peter A Follett ◽  
Fay E M Haynes ◽  
Bernard C Dominiak
Keyword(s):  
Fruit Fly ◽  
Fruit Production ◽  
General Purpose ◽  
Fruit Flies ◽  
Host Suitability ◽  
Bactrocera Dorsalis ◽  
Infestation Rate ◽  
Suitability Index ◽  
Host Status ◽  
Tephritid Fruit Flies

Abstract Tephritid fruit flies are major economic pests for fruit production and are an impediment to international trade. Different host fruits are known to vary in their suitability for fruit flies to complete their life cycle. Currently, international regulatory standards that define the likely legal host status for tephritid fruit flies categorize fruits as a natural host, a conditional host, or a nonhost. For those fruits that are natural or conditional hosts, infestation rate can vary as a spectrum ranging from highly attractive fruits supporting large numbers of fruit flies to very poor hosts supporting low numbers. Here, we propose a Host Suitability Index (HSI), which divides the host status of natural and conditional hosts into five categories based on the log infestation rate (number of flies per kilogram of fruit) ranging from very poor (<0.1), poor (0.1–1.0), moderately good (1.0–10.0), good (10–100), and very good (>100). Infestation rates may be determined by field sampling or cage infestation studies. We illustrate the concept of this index using 21 papers that examine the host status of fruits in five species of polyphagous fruit flies in the Pacific region: Bactrocera tryoni Froggatt, Bactrocera dorsalis (Hendel), Bactrocera latifrons (Hendel), Zeugodacus cucurbitae (Coquillett), and Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). This general-purpose index may be useful in developing systems approaches that rely on poor host status, for determining surveillance and detection protocols for potential incursions, and to guide the appropriate regulatory response during fruit fly outbreaks.

scholarly journals Establishing criteria for the management of tephritid fruit fly outbreaks

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Michael D. Ormsby
Keyword(s):  
Cost Benefit ◽  
Fruit Fly ◽  
Economic Benefits ◽  
Fruit Flies ◽  
International Standards ◽  
Trade Restrictions ◽  
Export Restriction ◽  
Fly Control ◽  
Financial Impacts ◽  
Tephritid Fruit Flies

AbstractTephritid fruit flies (Diptera; Tephritidae) represent a group of insects that include some of the most economically important pests in horticulture. Because of their economic importance, the financial impacts of an incursion of tephritid fruit flies into a new area can often result in restrictions to trade. The economic impacts of any trade restrictions imposed by importing countries are confounded by the current absence of consistent and accepted criteria for the strength and extent of any trade restrictions and declaring the end of an incursion. The author has developed models that can be used to establish criteria for the management of tephritid fruit fly outbreaks as outlined in international standards. A model enables criteria on when to recognise an incursion has occurred and establish export restrictions. Another model determines what area or radius an export restriction zone (ERZ) should cover. And a third model establishes criteria for the conditions required to enable an ERZ to be rescinded and the area’s pest free status reinstated. The models rely primarily on fruit fly biology and the effectiveness of surveillance trapping systems. The adoption of these proposed criteria internationally for establishing a control system and responding to fruit fly outbreaks would provide considerable economic benefits to international trade. Additionally, these criteria would enable countries to make more informed cost–benefit decisions on the level of investment in fruit fly control systems that better reflects the economic risks fruit flies represent to their economy.

Effects of Face Mask Use on Objective and Subjective Measures of Thermoregulation During Exercise in the Heat

2021 ◽  
pp. 194173812110282
Author(s):  
Ayami Yoshihara ◽  
Erin E. Dierickx ◽  
Gabrielle J. Brewer ◽  
Yasuki Sekiguchi ◽  
Rebecca L. Stearns ◽  
...  
Keyword(s):  
Exercise Intensity ◽  
Thermal Sensation ◽  
Face Mask ◽  
Whole Body ◽  
Moderate Exercise ◽  
Physically Active ◽  
Time Points ◽  
The Face ◽  
And Control ◽  
Moderate Exercise Intensity

Background: While increased face mask use has helped reduce COVID-19 transmission, there have been concerns about its influence on thermoregulation during exercise in the heat, but consistent, evidence-based recommendations are lacking. Hypothesis: No physiological differences would exist during low-to-moderate exercise intensity in the heat between trials with and without face masks, but perceptual sensations could vary. Study Design: Crossover study. Level of Evidence: Level 2. Methods: Twelve physically active participants (8 male, 4 female; age = 24 ± 3 years) completed 4 face mask trials and 1 control trial (no mask) in the heat (32.3°C ± 0.04°C; 54.4% ± 0.7% relative humidity [RH]). The protocol was 60 minutes of walking and jogging between 35% and 60% of relative VO2max. Rectal temperature (Trec), heart rate (HR), temperature and humidity inside and outside of the face mask (Tmicro_in, Tmicro_out, RHmicro_in, RHmicro_out) and perceptual variables (rating of perceived exertion (RPE), thermal sensation, thirst sensation, fatigue level, and overall breathing discomfort) were monitored throughout all trials. Results: Mean Trec and HR increased at 30- and 60-minute time points compared with 0-minute time points, but no difference existed between face mask trials and control trials ( P > 0.05). Mean Tmicro_in, RHmicro_in, and humidity difference inside and outside of the face mask (ΔRHmicro) were significantly different between face mask trials ( P < 0.05). There was no significant difference in perceptual variables between face mask trials and control trials ( P > 0.05), except overall breathing discomfort ( P < 0.01). Higher RHmicro_in, RPE, and thermal sensation significantly predicted higher overall breathing discomfort ( r2 = 0.418; P < 0.01). Conclusion: Face mask use during 60 minutes of low-to-moderate exercise intensity in the heat did not significantly affect Trec or HR. Although face mask use may affect overall breathing discomfort due to the changes in the face mask microenvironment, face mask use itself did not cause an increase in whole body thermal stress. Clinical Relevance: Face mask use is feasible and safe during exercise in the heat, at low-to-moderate exercise intensities, for physically active, healthy individuals.

Non-host status of papaya cultivars to the oriental fruit fly, Bactrocera dorsalis (Diptera: Tephritidae), in relation to the degree of fruit ripeness

2016 ◽  
Vol 37 (01) ◽  
pp. 19-29 ◽  
Author(s):  
Domingos Cugala ◽  
João Jone Jordane ◽  
Sunday Ekesi
Keyword(s):  
Fruit Ripening ◽  
Market Access ◽  
Fruit Fly ◽  
Fruit Flies ◽  
Bactrocera Dorsalis ◽  
Laboratory Evaluation ◽  
Ripening Stage ◽  
Field Cage ◽  
Major Barrier ◽  
Ripening Stages

AbstractPhytosanitary measures are a major barrier to trade in papaya. We assessed the infestation of tephritid fruit flies on different stages of maturity of papaya, to determine its non-host stage of maturity, for market access. Papaya fruits were collected from Kilifi and Embu counties, Kenya from March 2013 to December 2014, to assess the level of infestation by fruit flies according to the degree of fruit ripening. In all locations, no fruit fly infestation was recorded on papaya when fruits were at the 0, 25 and 50% yellow fruit ripening stage.Bactrocera dorsalis(Hendel) was, however, observed attacking fruits when papaya fruits were at 75 and 100% all yellow (fully ripe fruit ripening stage) with infestations of 0.19−0.51B. dorsalis/kg fruit and 0.24−1.24B. dorsalis/kg fruit, respectively, in all locations. Field cage exposure ofB. dorsalisto fruits of five papaya cultivars—‘Papino’, ‘Neo Essence’, ‘Sunrise Solo’, ‘Tainung No. 1’ and ‘Tainung No. 2’ in Manica Province, Mozambique—showed thatB. dorsalisdid not infest fruits at 0, 25 and 50% yellow ripening stages at the densities of 50 and 100 flies per cage. However, at 75% yellow ripening stage, up to 13.1 pupae/kg of fruits was recorded at a density of 150 flies per cage in Tainung No. 1, and infestation ranged from 4.5 to 136 pupae/kg fruits at 100% yellow ripening stage across all the cultivars and infestation densities. Laboratory evaluation of volatiles emanating from freshly crushed papaya pulp of four cultivars: ‘Sunrise Solo’, ‘Red Lady’, ‘Papayi’ and ‘Apoyo’ on egg viability ofB. dorsalisshowed that at 0, 25 and 50% yellow, egg hatchability was inhibited, suggesting that semiochemical compounds present in green tissues of papaya prevent egg development, although this effect was variable across the four cultivars and ripening stages. Export papaya is harvested at less than 40% yellow ripening stage. Our results, therefore, suggest that quarantine treatment for fruits at this ripening stage is inconsequential, asB. dorsalisdoes not infest papaya fruits at this stage; thus, authorities should permit entry of these papaya cultivars of less than 40% yellow ripening stage to quarantine-sensitive markets.

scholarly journals Diversity and seasonality of fruit flies (Diptera: Tephritidae and Lonchaeidae) and their parasitoids (Hymenoptera: Braconidae and Figitidae) in orchards of guava, loquat and peach

2009 ◽  
Vol 69 (1) ◽  
pp. 31-40 ◽  
Author(s):  
MF. Souza-Filho ◽  
A. Raga ◽  
JA. Azevedo-Filho ◽  
PC. Strikis ◽  
JA. Guimarães ◽  
...  
Keyword(s):  
Population Density ◽  
Ceratitis Capitata ◽  
Fruit Fly ◽  
Fruit Flies ◽  
Parasitoid Species ◽  
Seasonal Behavior ◽  
Leptopilina Boulardi ◽  
Torula Yeast ◽  
Tephritid Species

This work was carried out in orchards of guava progenies, and loquat and peach cultivars, in Monte Alegre do Sul, SP, Brazil, in 2002 and 2003. Guavas and loquats were bagged and unbagged bi-weekly and weekly, respectively, for assessment of the infestation period. Peach was only bagged weekly. The assays started when the fruits were at the beginning of development, but still green. Ripe fruits were taken to the laboratory and placed individually into plastic cups. McPhail plastic traps containing torula yeast were hung from January 2002 to January 2004 to assess the fruit fly population in each orchard, but only the Ceratitis capitata population is here discussed. Five tephritid species were reared from the fruits: Anastrepha bistrigata Bezzi, A. fraterculus (Wiedemann), A. obliqua (Macquart), A. sororcula Zucchi, and C. capitata, in addition to six lonchaeid species: Neosilba certa (Walker), N. glaberrima (Wiedemann), N. pendula (Bezzi), N. zadolicha McAlpine and Steyskal, Neosilba sp. 4, and Neosilba sp. 10 (both species are in the process of being described by P. C. Strikis), as well as some unidentified Neosilba species. Ten parasitoid species were obtained from fruit fly puparia, of which five were braconids: Asobara anastrephae (Muesebeck), Doryctobracon areolatus (Szépligeti), D. brasiliensis (Szépligeti), Opius bellus Gahan, and Utetes anastrephae (Viereck), and five figitids: Aganaspis pelleranoi (Brèthes), Dicerataspis grenadensis Ashmead, Lopheucoila anastrephae (Rhower), Leptopilina boulardi (Barbotin, Carlton and Kelner-Pillaut), and Trybliographa infuscata Diaz, Gallardo and Uchôa. Ceratitis capitata showed a seasonal behavior with population density peaking at the second semester of each year. Anastrepha and Neosilba species remained in the orchards throughout both years.

Whole body extract of Mediterranean fruit fly males elicits high attraction in virgin females

2008 ◽  
Vol 127 (1) ◽  
pp. 20-29 ◽  
Author(s):  
Vassilis G. Mavraganis ◽  
Constandinos Liaropoulos ◽  
Nikos T. Papadopoulos ◽  
Nikos A. Kouloussis ◽  
Theodoros Broumas
Keyword(s):  
Fruit Fly ◽  
Mediterranean Fruit Fly ◽  
Whole Body ◽  
Body Extract ◽  
High Attraction

scholarly journals Serum betaine is inversely associated with low lean mass mainly in men in a Chinese middle-aged and elderly community-dwelling population

2016 ◽  
Vol 115 (12) ◽  
pp. 2181-2188 ◽  
Author(s):  
Bi-xia Huang ◽  
Ying-ying Zhu ◽  
Xu-ying Tan ◽  
Qiu-ye Lan ◽  
Chun-lei Li ◽  
...  
Keyword(s):  
Lean Mass ◽  
Community Dwelling ◽  
The Body ◽  
Muscle Performance ◽  
Whole Body ◽  
Composition Analysis ◽  
Human Beings ◽  
Middle Aged ◽  
Chinese Adults ◽  
Skeletal Muscle Index

AbstractPrevious studies have demonstrated that betaine supplements increase lean body mass in livestock and improve muscle performance in human beings, but evidence for its effect on human lean mass is limited. Our study assessed the association of circulating betaine with lean mass and its composition in Chinese adults. A community-based study was conducted on 1996 Guangzhou residents (weight/mass: 1381/615) aged 50–75 years between 2008 and 2010. An interviewer-administered questionnaire was used to collect general baseline information. Fasting serum betaine was assessed using HPLC-MS. A total of 1590 participants completed the body composition analysis performed using dual-energy X-ray absorptiometry during a mean of 3·2 years of follow-up. After adjustment for age, regression analyses demonstrated a positive association of serum betaine with percentage of lean mass (LM%) of the entire body, trunk and limbs in men (all P<0·05) and LM% of the trunk in women (P=0·016). Each sd increase in serum betaine was associated with increases in LM% of 0·609 (whole body), 0·811 (trunk), 0·422 (limbs), 0·632 (arms) and 0·346 (legs) in men and 0·350 (trunk) in women. Multiple logistic regression analysis revealed that the prevalence of lower LM% decreased by 17 % (whole body) and 14 % (trunk) in women and 23 % (whole body), 28 % (trunk), 22 % (arms) and 26 % (percentage skeletal muscle index) in men with each sd increment in serum betaine. Elevated circulating betaine was associated with a higher LM% and lower prevalence of lower LM% in middle-aged and elderly Chinese adults, particularly men.

Species composition and host range of fruit-infesting flies (Diptera: Tephritidae) in northern Ghana

2015 ◽  
Vol 35 (03) ◽  
pp. 137-151 ◽  
Author(s):  
K.B. Badii ◽  
M.K. Billah ◽  
K. Afreh-Nuamah ◽  
D. Obeng-Ofori
Keyword(s):  
Host Range ◽  
Plant Species ◽  
Host Plants ◽  
Management Strategies ◽  
Fruit Fly ◽  
Fruit Flies ◽  
Northern Ghana ◽  
Accurate Information ◽  
Wild Host ◽  
Fruit Samples

An important aspect of fruit fly management is accurate information on the species and their host spectrum. Studies were conducted between October 2011 and September 2013 to determine the host range and species diversity of pest fruit flies in the northern savannah ecology of Ghana. Fruit samples from 80 potential host plants (wild and cultivated) were collected and incubated for fly emergence; 65 (81.5%) of the plant species were positive to fruit flies. From records in Africa, 11 plant species were reported to be new hosts to the African invader fly,Bactrocera invadens(Drew, Tsuruta and White, 2005). This study documented the first records ofDacus ciliatus(Loew) andTrirhithrum nigerrimum(Bezzi) in northern Ghana although both species have been previously reported in other parts of the country. Infestation byB. invadenswas higher in the cultivated fruits;Ceratitis cosyradominated in most wild fruits. Cucurbitaceae were mainly infested by three species ofDacusandBactroceracucurbitae, a specialized cucurbit feeder. Among the commercial fruit species, the highest infestations were observed in mango, tomato, sweet pepper and watermelon, whereas marula plum, soursop, tropical almond, sycamore fig, African peach, shea nut, persimmon, icacina and albarillo dominated the wild host flora. The widespread availability of host plants and the incidence of diverse fly species in the ecology call for particular attention to their impact on commercial fruits and the development of sustainable management strategies against these economically important pests in Ghana.

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