The initiation of sex differentiation in insects is regulated by primary sex determination signals.In the Medfly Ceratitis capitata and other tephritids,Maleness-on-the-Y(MoY) is the master gene for male sex determina...The initiation of sex differentiation in insects is regulated by primary sex determination signals.In the Medfly Ceratitis capitata and other tephritids,Maleness-on-the-Y(MoY) is the master gene for male sex determination.However,the primary signal in Zeugodacus cucurbitae(Coquillett),a very destructive tephritid pest across the world,remains ambiguous.In this study,we have isolated and characterized the Medfly MoY homolog in Z.cucurbitae,ZcMoY.ZcMOY protein shows high sequence conservation to its homologs in Bactrocera species.ZcMoY transcription begins and peaks at very early embryonic stages and then becomes undetectable except the testes and heads of day 1 male adults.Silencing ZcMoY in early embryos by RNAi causes abnormal external genitalia and interior reproductive organs,giving rise to intersexes and feminization of XY individuals.The expression pattern and knockdown phenotypes of ZcMoY indicate that ZcMoY plays a key role in regulating sex determination of Z.cucurbitae males.Our findings will help the understanding of sex determination in Z.cucurbitae and facilitate the development of genetic sexing strains in its biological control.展开更多
Detection of F. solani f. sp. cucurbitae causal agent of the crown and root rot disease of melon race 1, race 2 is difficult. It is based only on morphological characteristic. In this study, forty isolates identified ...Detection of F. solani f. sp. cucurbitae causal agent of the crown and root rot disease of melon race 1, race 2 is difficult. It is based only on morphological characteristic. In this study, forty isolates identified as Fusarium solani based on morphological characterization, F. solani was one of the most frequently isolated species. Molecular identification of these isolates by PCR technique using species-specific primer, indicated that thirty-two isolates, amplified product 580 bp (race 1) and two isolate amplified product 580 bp (race 2), while six isolates were not amplified with primer of both races. Production of Trichothecenes (T2-toxen, DON.) by Fusarium solani was conducted on isolates confirmed as belonging in the F. solani by PCR. The results indicated that the presence of Tri5, Tri13 genes is coding the ability of synthesis mycotoxin. In vitro, the results indicated that NPs (AgNPs, MgNPs) and chemical (Phylex) possess the antifungal properties against at various level. Treatment with (AgNPs 150 ppm, MgNPs 2%, 3% ppm) and 3% Phylex resulted in maximum inhabitation of F. solani . In vivo, five characters (height plant, hoot ant root fresh and dry weight) were measured based on the greenhouse, field experimental results. Treatment with (AgNPs, MgNPs) and Phylex had higher measured parameters than positive control.展开更多
transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbi...transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbitae(Coquillett) is a very destructive pest worldwide, however, its sex determination pathway remains largely uncharacterized. Here, we show that the female sex ratio is sharply reduced with knockdown of either transformer or transformer-2 by RNA interference in early embryos of Z. cucurbitae. Most of the males grown from the embryos with transient transformer and transformer-2 suppression mated with wild-type females and produced mixed sex progeny, with one exception that produced only female progeny, and all of the few remaining males failed to mate with wild-type females and produced no progeny. The exceptional male and those males with mating failure were XX pseudomales as determined by the detection of Y chromosome-linked Maleness-on-the-Y, indicating that most XX pseudomales are not viable. The phenotypes of transformer and transformer-2 suggest that they play a key role in regulating sex determination and are required for female sexual development of Z. cucurbitae. Our results will be beneficial to the understanding of sex determination in Z. cucurbitae and can facilitate the development of genetic sexing strains for its biological control.展开更多
Five different trapping treatments, spraying attractant on bottle surface and spraying attractant inside the bottles with 0, 50,100 and 200 mL water, were set to trap Bactrocera dorsalis and B. cucurbitae in guava (P...Five different trapping treatments, spraying attractant on bottle surface and spraying attractant inside the bottles with 0, 50,100 and 200 mL water, were set to trap Bactrocera dorsalis and B. cucurbitae in guava (Psidium guajava) park. The results showed that when the usage of attractant was 1 g, both Haonian and Wende had trapping effect on B. dorsalis and B. cucurbitae. The trapping effect of Haonian on B. dorsalis was better than that of Wende, while their trapping effects on B. cucurbitae was just the opposite. The trapping effects of different treatments had great difference. The trapping effect of Haonian on two species of fruit flies enhanced with the increasing volume of water, and reached the ma^mum value as the water volume was 200 mL. With the increasing volume of water, the trap- ping effect of Wende on two species of fruit flies first increased, and then decreased, which reached the maximum value as the water volume was 50 mL. Different treatments with attractants spraying inside bottles had better trapping effects on two species of fruit flies than that spraying on bottle surface.展开更多
Previous studies have shown oviposition deterring properties of 8 coconut free fatty acid(CFFA)compounds on fruit flies with different key deterrent components for different species.Here we evaluated oviposition deter...Previous studies have shown oviposition deterring properties of 8 coconut free fatty acid(CFFA)compounds on fruit flies with different key deterrent components for different species.Here we evaluated oviposition deterrence of CFFA using laboratory 2-choice bioassays against Zeugodacus cucurbitae,determined key-bioactive deterrent compounds,and evaluated their behavioral mode.Unlike other reported fruit fly species,CFFA mixture increased Z.cucurbitae oviposition when directly applied on an oviposition substrate.When tested individually in subsequent tests,4 compounds(caprylic,capric,oleic,and linoleic acids)significantly reduced the oviposition(“negative-compounds”),1 compound(stearic acid)had no effect(“neutral-compound”),and 3 compounds(lauric,myristic,and palmitic acids)stimulated the oviposition(“positive-compounds”).The 4-component negative-compound blend was effective at reducing oviposition.However,adding stearic acid to the 4-component blend(5-component blend,5c)further reduced oviposition.Adding any of the positive-compounds to the 5c resulted in loss of oviposition deterrence,suggesting the 5c as the key deterrent component blend.The blend was also effective in no-choice assays and when applied on cucumbers,a preferred host of Z.cucurbitae.When given a choice,Z.cucurbitae made 48.5%fewer visits,spent 39%less time,and oviposited 88.2%fewer eggs per min on 5c treated pumpkin agar than on control agar,suggesting that the 5c blend has both spatial repellency and contact deterrence.Given that all compounds are registered food additives and generally regarded as safe,this blend has potential application in behavioral control strategies,such as push-pull,to protect host fruit against Z.cucurbitae.展开更多
Age-stage, two-sex life tables of the melon fly, Bactrocera cucurbitae (Coquil- let-t) (Diptera: Tephritidae), reared on cucumber (Cucumis sativus L.), sponge gourd (Luffa cylindrica Roem) and a carrot medium...Age-stage, two-sex life tables of the melon fly, Bactrocera cucurbitae (Coquil- let-t) (Diptera: Tephritidae), reared on cucumber (Cucumis sativus L.), sponge gourd (Luffa cylindrica Roem) and a carrot medium (mashed Daucus carota L. mixed with sucrose and yeast hydrolysate) were constructed under laboratory conditions at 25 4- loc, 65% 4- 0.5% relative humidity, and a photoperiod 12 : 12h (L : D). The intrinsic rates of increase of B. cucurbitae were 0.144 6, 0.141 2 and 0.068 8 days on cucumber, sponge gourd, and carrot medium, respectively. The highest net reproduction rate was 172 offspring per fly reared on sponge gourd. The mean generation times ofB. cucurbitae ranged from 34 days reared on cucumber to 56 days reared on carrot medium. The life history raw data was analyzed using the traditional female age-specific life table and compared to results obtained using the age-stage, two-sex life table. When the age-specific female life table is applied to an age-stage-structured two-sex population, survival and fecundity curves will be improperly manipulated due to an inability to include variation in preadult development time. We discussed different interpretations of the relationship between the net reproductive rate and the intrinsic rate of increase to clarify possible misunderstanding in the literature.展开更多
Methoprene (an analogue of juvenile hormone) application and feeding on a protein diet is known to enhance male melon fly, Bactrocera cucurbitae Coquillett (Diptera: Tephritidae), mating success. In this study, w...Methoprene (an analogue of juvenile hormone) application and feeding on a protein diet is known to enhance male melon fly, Bactrocera cucurbitae Coquillett (Diptera: Tephritidae), mating success. In this study, we investigated the effect of these treatments on male B. cucurbitae's ability to inhibit female remating. While 14-d-old females were fed on protein diet, 6-d-old males were exposed to one of the following treatments: (i) topical application of methoprene and fed on a protein diet; (ii) no methoprene but fed on a protein diet; (iii) methoprene and sugar-fed only; and (iv) sugar-fed, 14-d-old males acted as controls. Treatments had no effect on a male's ability to depress the female remating receptivity in comparison to the control. Females mated with protein-deprived males showed higher remating receptivity than females first mated with protein-fed males. Methoprene and protein diet interaction had a positive effect on male mating success during the first and second mating of females. Significantly more females first mated with sugar-fed males remated with protein-fed males and females first mated with methoprene treated and protein-fed males were more likely to remate with similarly treated males. Females mating latency (time to start mating) was significantly shorter with protein-fed males, and mating duration was significantly longer with protein-fed males compared with protein-deprived males. These results are discussed in the context of methoprene and/or dietary protein as prerelease treatment of sterile males in area-wide control of melon fly integrating the sterile insect technique (SIT).展开更多
The melon fruit fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae), has been the subject of worldwide quarantine and management efforts due to its widespread agricultural impact and potential for rapi...The melon fruit fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae), has been the subject of worldwide quarantine and management efforts due to its widespread agricultural impact and potential for rapid range expansion. From its presumed native distribution in India, this species has spread throughout the hot-humid regions of the world. We provide information that reveals population structure, invasion history and population connectivity from 23 locations covering nine countries based on DNA sequences of the mitochondrial cytochrome oxidase I (COI) gene. Forty-two polymorphic sites were described among 38 haplotypes. The most common haplotype, H1, was observed in 73% of the samples distributed among all populations. Highest genetic diversity was seen within populations, and no isolation-by-distance was detected. The western regions (Nepal, Bangladesh, Thailand, Burma and China-west) showed higher haplotype diversity than eastern regions (China-east). China-Yunnan showed highest levels of genetic diversity in China. Haplotype diversity decreased with longitude from west to east. Together, these analyses suggest that B. cueurbitae has expanded from west to east within a limited geographic scale and recently invaded China through Yunnan Province.展开更多
Grafting is widely used in cucumbers to enhance their tolerance to environmental stress.Compatibility is a key factor for successful grafting,however,the physiological mechanisms that affect grafting compatibility are...Grafting is widely used in cucumbers to enhance their tolerance to environmental stress.Compatibility is a key factor for successful grafting,however,the physiological mechanisms that affect grafting compatibility are not clear.This study aimed to investigate the physiological mechanism underlying cucumber/pumpkin grafting compatibility.Two pumpkin cultivars with significant differences in compatibility,Figleaf gourd(compatible rootstock,Cf)and Dongyangshenli(incompatible rootstock,Cmo),were used as rootstocks.Three cucumber cultivars with different growth rates were used as scions,including cucumber‘Shenluchunsi’(strong growth,V1),‘Cuilü’(weak growth,V2),and‘Liangyoulüjian 102’(medium growth,V3).Six grafting combinations(V1/Cf,V2/Cf,V3/Cf,V1/Cmo,V2/Cmo,and V3/Cmo)were used to analyze the effect of scion and rootstock varieties,as well as the chemical composition of the exudate from the stem cutting surface,on the compatibility of grafted plants.Here,we found that rootstock was closely correlated with the compatibility of cucumber/pumpkin grafted plants.The sucrose content in the exudate of the stem,enzyme activity,and the expression of genes related to sucrose biosynthesis in Cmo were significantly higher than those in Cf.Correlation analysis showed that the sucrose content difference between the exudate of rootstock and scion stems was negatively correlated with graft compatibility.Exogenous treatment with a 0.5%sucrose solution on the scions significantly reduced the difference in sucrose content between rootstock and scion and enhanced graft survival rate in the incompatible combination.The stem segment grafting experiment in vitro found that the high difference in sucrose concentration between the rootstock and scion decreased the grafting compatibility of cucumber/pumpkin by reducing the adhesion of the cutting surface.Taken together,the higher sucrose concentration difference between rootstock and scion decreased the adhesion of the cutting surface,resulting in the incompatibility of cucumber/pumpkin grafted plants.展开更多
基金supported by the the National Natural Science Foundation of China (31702059, 31860523, and 31660339)the Hainan Provincial Natural Science Foundation of China (321CXTD435)。
文摘The initiation of sex differentiation in insects is regulated by primary sex determination signals.In the Medfly Ceratitis capitata and other tephritids,Maleness-on-the-Y(MoY) is the master gene for male sex determination.However,the primary signal in Zeugodacus cucurbitae(Coquillett),a very destructive tephritid pest across the world,remains ambiguous.In this study,we have isolated and characterized the Medfly MoY homolog in Z.cucurbitae,ZcMoY.ZcMOY protein shows high sequence conservation to its homologs in Bactrocera species.ZcMoY transcription begins and peaks at very early embryonic stages and then becomes undetectable except the testes and heads of day 1 male adults.Silencing ZcMoY in early embryos by RNAi causes abnormal external genitalia and interior reproductive organs,giving rise to intersexes and feminization of XY individuals.The expression pattern and knockdown phenotypes of ZcMoY indicate that ZcMoY plays a key role in regulating sex determination of Z.cucurbitae males.Our findings will help the understanding of sex determination in Z.cucurbitae and facilitate the development of genetic sexing strains in its biological control.
文摘Detection of F. solani f. sp. cucurbitae causal agent of the crown and root rot disease of melon race 1, race 2 is difficult. It is based only on morphological characteristic. In this study, forty isolates identified as Fusarium solani based on morphological characterization, F. solani was one of the most frequently isolated species. Molecular identification of these isolates by PCR technique using species-specific primer, indicated that thirty-two isolates, amplified product 580 bp (race 1) and two isolate amplified product 580 bp (race 2), while six isolates were not amplified with primer of both races. Production of Trichothecenes (T2-toxen, DON.) by Fusarium solani was conducted on isolates confirmed as belonging in the F. solani by PCR. The results indicated that the presence of Tri5, Tri13 genes is coding the ability of synthesis mycotoxin. In vitro, the results indicated that NPs (AgNPs, MgNPs) and chemical (Phylex) possess the antifungal properties against at various level. Treatment with (AgNPs 150 ppm, MgNPs 2%, 3% ppm) and 3% Phylex resulted in maximum inhabitation of F. solani . In vivo, five characters (height plant, hoot ant root fresh and dry weight) were measured based on the greenhouse, field experimental results. Treatment with (AgNPs, MgNPs) and Phylex had higher measured parameters than positive control.
基金supported by the Hainan Provincial Natural Science Foundation of China(321CXTD435)the National Natural Science Foundation of China(31860523,31660339,31702059,and 32260665)the National Key R&D Program of China(2022YFC2601400)。
文摘transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbitae(Coquillett) is a very destructive pest worldwide, however, its sex determination pathway remains largely uncharacterized. Here, we show that the female sex ratio is sharply reduced with knockdown of either transformer or transformer-2 by RNA interference in early embryos of Z. cucurbitae. Most of the males grown from the embryos with transient transformer and transformer-2 suppression mated with wild-type females and produced mixed sex progeny, with one exception that produced only female progeny, and all of the few remaining males failed to mate with wild-type females and produced no progeny. The exceptional male and those males with mating failure were XX pseudomales as determined by the detection of Y chromosome-linked Maleness-on-the-Y, indicating that most XX pseudomales are not viable. The phenotypes of transformer and transformer-2 suggest that they play a key role in regulating sex determination and are required for female sexual development of Z. cucurbitae. Our results will be beneficial to the understanding of sex determination in Z. cucurbitae and can facilitate the development of genetic sexing strains for its biological control.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest( 201103026-1)
文摘Five different trapping treatments, spraying attractant on bottle surface and spraying attractant inside the bottles with 0, 50,100 and 200 mL water, were set to trap Bactrocera dorsalis and B. cucurbitae in guava (Psidium guajava) park. The results showed that when the usage of attractant was 1 g, both Haonian and Wende had trapping effect on B. dorsalis and B. cucurbitae. The trapping effect of Haonian on B. dorsalis was better than that of Wende, while their trapping effects on B. cucurbitae was just the opposite. The trapping effects of different treatments had great difference. The trapping effect of Haonian on two species of fruit flies enhanced with the increasing volume of water, and reached the ma^mum value as the water volume was 200 mL. With the increasing volume of water, the trap- ping effect of Wende on two species of fruit flies first increased, and then decreased, which reached the maximum value as the water volume was 50 mL. Different treatments with attractants spraying inside bottles had better trapping effects on two species of fruit flies than that spraying on bottle surface.
基金supported in part by funding from Plant Protection Act 7721 funding to Dong H.Cha,Amy Roda,Junwei Zhu,and Paul Kendra(#2021-6.1171)Jia-Wei Tay and Dong H.Cha(AP22PPQS&T00C067)a CRADA with Marron Bio Innovations,Inc to Dong H.Cha and Junwei Zhu(#58-2040-0-004)。
文摘Previous studies have shown oviposition deterring properties of 8 coconut free fatty acid(CFFA)compounds on fruit flies with different key deterrent components for different species.Here we evaluated oviposition deterrence of CFFA using laboratory 2-choice bioassays against Zeugodacus cucurbitae,determined key-bioactive deterrent compounds,and evaluated their behavioral mode.Unlike other reported fruit fly species,CFFA mixture increased Z.cucurbitae oviposition when directly applied on an oviposition substrate.When tested individually in subsequent tests,4 compounds(caprylic,capric,oleic,and linoleic acids)significantly reduced the oviposition(“negative-compounds”),1 compound(stearic acid)had no effect(“neutral-compound”),and 3 compounds(lauric,myristic,and palmitic acids)stimulated the oviposition(“positive-compounds”).The 4-component negative-compound blend was effective at reducing oviposition.However,adding stearic acid to the 4-component blend(5-component blend,5c)further reduced oviposition.Adding any of the positive-compounds to the 5c resulted in loss of oviposition deterrence,suggesting the 5c as the key deterrent component blend.The blend was also effective in no-choice assays and when applied on cucumbers,a preferred host of Z.cucurbitae.When given a choice,Z.cucurbitae made 48.5%fewer visits,spent 39%less time,and oviposited 88.2%fewer eggs per min on 5c treated pumpkin agar than on control agar,suggesting that the 5c blend has both spatial repellency and contact deterrence.Given that all compounds are registered food additives and generally regarded as safe,this blend has potential application in behavioral control strategies,such as push-pull,to protect host fruit against Z.cucurbitae.
文摘Age-stage, two-sex life tables of the melon fly, Bactrocera cucurbitae (Coquil- let-t) (Diptera: Tephritidae), reared on cucumber (Cucumis sativus L.), sponge gourd (Luffa cylindrica Roem) and a carrot medium (mashed Daucus carota L. mixed with sucrose and yeast hydrolysate) were constructed under laboratory conditions at 25 4- loc, 65% 4- 0.5% relative humidity, and a photoperiod 12 : 12h (L : D). The intrinsic rates of increase of B. cucurbitae were 0.144 6, 0.141 2 and 0.068 8 days on cucumber, sponge gourd, and carrot medium, respectively. The highest net reproduction rate was 172 offspring per fly reared on sponge gourd. The mean generation times ofB. cucurbitae ranged from 34 days reared on cucumber to 56 days reared on carrot medium. The life history raw data was analyzed using the traditional female age-specific life table and compared to results obtained using the age-stage, two-sex life table. When the age-specific female life table is applied to an age-stage-structured two-sex population, survival and fecundity curves will be improperly manipulated due to an inability to include variation in preadult development time. We discussed different interpretations of the relationship between the net reproductive rate and the intrinsic rate of increase to clarify possible misunderstanding in the literature.
文摘Methoprene (an analogue of juvenile hormone) application and feeding on a protein diet is known to enhance male melon fly, Bactrocera cucurbitae Coquillett (Diptera: Tephritidae), mating success. In this study, we investigated the effect of these treatments on male B. cucurbitae's ability to inhibit female remating. While 14-d-old females were fed on protein diet, 6-d-old males were exposed to one of the following treatments: (i) topical application of methoprene and fed on a protein diet; (ii) no methoprene but fed on a protein diet; (iii) methoprene and sugar-fed only; and (iv) sugar-fed, 14-d-old males acted as controls. Treatments had no effect on a male's ability to depress the female remating receptivity in comparison to the control. Females mated with protein-deprived males showed higher remating receptivity than females first mated with protein-fed males. Methoprene and protein diet interaction had a positive effect on male mating success during the first and second mating of females. Significantly more females first mated with sugar-fed males remated with protein-fed males and females first mated with methoprene treated and protein-fed males were more likely to remate with similarly treated males. Females mating latency (time to start mating) was significantly shorter with protein-fed males, and mating duration was significantly longer with protein-fed males compared with protein-deprived males. These results are discussed in the context of methoprene and/or dietary protein as prerelease treatment of sterile males in area-wide control of melon fly integrating the sterile insect technique (SIT).
文摘The melon fruit fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae), has been the subject of worldwide quarantine and management efforts due to its widespread agricultural impact and potential for rapid range expansion. From its presumed native distribution in India, this species has spread throughout the hot-humid regions of the world. We provide information that reveals population structure, invasion history and population connectivity from 23 locations covering nine countries based on DNA sequences of the mitochondrial cytochrome oxidase I (COI) gene. Forty-two polymorphic sites were described among 38 haplotypes. The most common haplotype, H1, was observed in 73% of the samples distributed among all populations. Highest genetic diversity was seen within populations, and no isolation-by-distance was detected. The western regions (Nepal, Bangladesh, Thailand, Burma and China-west) showed higher haplotype diversity than eastern regions (China-east). China-Yunnan showed highest levels of genetic diversity in China. Haplotype diversity decreased with longitude from west to east. Together, these analyses suggest that B. cueurbitae has expanded from west to east within a limited geographic scale and recently invaded China through Yunnan Province.
基金supported by grants from the Gansu Provincial Science and Technology Plan Project(Grant No.22CX8NA030)the National Natural Science Foundation of China(Grant No.32272793)the China Agriculture Research System(Grant No.CARS-23).
文摘Grafting is widely used in cucumbers to enhance their tolerance to environmental stress.Compatibility is a key factor for successful grafting,however,the physiological mechanisms that affect grafting compatibility are not clear.This study aimed to investigate the physiological mechanism underlying cucumber/pumpkin grafting compatibility.Two pumpkin cultivars with significant differences in compatibility,Figleaf gourd(compatible rootstock,Cf)and Dongyangshenli(incompatible rootstock,Cmo),were used as rootstocks.Three cucumber cultivars with different growth rates were used as scions,including cucumber‘Shenluchunsi’(strong growth,V1),‘Cuilü’(weak growth,V2),and‘Liangyoulüjian 102’(medium growth,V3).Six grafting combinations(V1/Cf,V2/Cf,V3/Cf,V1/Cmo,V2/Cmo,and V3/Cmo)were used to analyze the effect of scion and rootstock varieties,as well as the chemical composition of the exudate from the stem cutting surface,on the compatibility of grafted plants.Here,we found that rootstock was closely correlated with the compatibility of cucumber/pumpkin grafted plants.The sucrose content in the exudate of the stem,enzyme activity,and the expression of genes related to sucrose biosynthesis in Cmo were significantly higher than those in Cf.Correlation analysis showed that the sucrose content difference between the exudate of rootstock and scion stems was negatively correlated with graft compatibility.Exogenous treatment with a 0.5%sucrose solution on the scions significantly reduced the difference in sucrose content between rootstock and scion and enhanced graft survival rate in the incompatible combination.The stem segment grafting experiment in vitro found that the high difference in sucrose concentration between the rootstock and scion decreased the grafting compatibility of cucumber/pumpkin by reducing the adhesion of the cutting surface.Taken together,the higher sucrose concentration difference between rootstock and scion decreased the adhesion of the cutting surface,resulting in the incompatibility of cucumber/pumpkin grafted plants.