Wolbachia is a symbiotic bacterium that alters reproductive behavior of numerous arthropods. It is the most advanced way to study phytogeny and classification based on sequences of the wsp gene. The presence of Wolbac...Wolbachia is a symbiotic bacterium that alters reproductive behavior of numerous arthropods. It is the most advanced way to study phytogeny and classification based on sequences of the wsp gene. The presence of Wolbachia in a lab strain of the thelytokous Trichogramma cacoeciae was firstly identified based on amplification and sequencing part of the wsp gene. Aligned the resulting sequence with the published ones, the phylogenetic relationships among Wolbachia which was found in T. cacoeciae, T. dendrolimi and other insects were established. The Wolbachia that found in T. cacoeciae and in T. dendrolimi belong to the Kue group and the Pip group, respectively.展开更多
Intercropping maize with the prostrate variety of mungbean, Vigna radiata (L.) Wilczek which grows flat along the ground can increase parasitism of the eggs of the Asian corn borer, Ostrinia furnacalis (Guenée...Intercropping maize with the prostrate variety of mungbean, Vigna radiata (L.) Wilczek which grows flat along the ground can increase parasitism of the eggs of the Asian corn borer, Ostrinia furnacalis (Guenée), a crucial insect pest of maize in China, by Trichogramma ostriniae Pang Chen. This study investigated the behavioural responses of T. ostriniae to plant volatiles emitted from whole plants, leaves, and flowers of prostrate and erect varieties of mungbean in a 4-armed olfactometer. Female parasitiods were significantly attracted to the odours from some varieties of prostrate mungbean when the visit duration and the number of visits were considered, but were not attracted to the odours from any erect varieties. The attractive odours were shown to emanate from the leaves, rather than from the flowers of prostrate mungbean plants. These results have implications for the augmentation of Trichogramma parasitoids in bio-control of O. furnacalis and other crop pests.展开更多
The results of evaluation on field control efficacy of Trichogramma dendrolimi against Ostrinia furnacalis showed that the correction rates of Ostrinia furnacalis egg mass parasitism were 71.75% and 73.57%,the average...The results of evaluation on field control efficacy of Trichogramma dendrolimi against Ostrinia furnacalis showed that the correction rates of Ostrinia furnacalis egg mass parasitism were 71.75% and 73.57%,the average control effect were 65.85% and 70.24%,the restoration yield loss rates were 6.78% and 7.97%,input-output ratio at 1:27.8 and 1:33.5 in Longjiang county of Heilongjiang province in 2009 and 2010,respectively.The technology is a integration of advanced,practical,environmental safety,effective biocontrol measures,embodies the "public plant protection,green plant protection" fully,has significant economic,social and ecological benefits.展开更多
The technology based on specific PCR amplification using internal transcribed spacer 2 of nuclear ribosomal DNA for molecular identification and detection of Trichogramma species was studied. Firstly the ITS2s of six ...The technology based on specific PCR amplification using internal transcribed spacer 2 of nuclear ribosomal DNA for molecular identification and detection of Trichogramma species was studied. Firstly the ITS2s of six Trichogramma species were cloned and sequenced, and the interspecific sequence variation was analyzed. Secondly the ITS2 regions of six geographical populations of T. dendrolimi were cloned and sequenced, and the intraspecific sequence identity was analyzed. The results show that the interspecific variation and intraspecific similarity of ITS2 sequences are very suitable for designation of specific primers at species-level. Screening of specific primers for T. dendrolimi leads to final sensitive and stable diagnostic primers. This system lets non-specialists can not only identify adults (males and females), but also identify eggs in parasitized hosts rapidly and accurately, which is impossible by conventional methods. Further development of this protocol can create a complete set of specific primers for different species of the whole genus Trichogramma .展开更多
This study investigated the direct effect of the insecticides deltamethrin and spinosad on three egg parasitoids species: Trichogramma oleae, T. cacoeciae and T. bourarachae. The parasitoid pupae were exposed to pesti...This study investigated the direct effect of the insecticides deltamethrin and spinosad on three egg parasitoids species: Trichogramma oleae, T. cacoeciae and T. bourarachae. The parasitoid pupae were exposed to pesticide residues on fresh olive tree leaves at recommended concentrations (RC) at different time intervals: 3, 10, 17, 24 and 31 days after pesticide applications. Parasitism viability (% emergence from parasitized eggs) and adult emergence time (developmental time from pupa to adult emergence) were evaluated. Regarding to the International Organization of Biological Control (IOBC) guidelines, results of toxicity effects of insecticides show that: Deltamethrin was moderately harmful to all Trichogramma species at RC (Decis®100 milliliters·ha−1), however, spinosad was harmless to moderately harmful at RC (Tracer®20 milliliters·ha−1). Trichogramma species revealed differences with regard to adult emergence time and exhibited significant changes in parasitism viability with increasing time after pesticide treatment. While deltamethrin residues affected parasitism viability 31 days after the product application, spinosad displayed similar viability for almost species 24 days after the application. The usefulness of Trichogramma parasitoids used as biological control agents, in olive tree ecosystem, was discussed in integrated pest management programs for Prays oleae control when parasitoid species were exposed during pupal stage to the insecticide residue.展开更多
In this study, we investigated the efficiency of T. brassicae and T. embryophagum in combination with bacterial suspension of B. thuringiensis against the tomato leafminer T. absoluta eggs in cage inside greenhouse (s...In this study, we investigated the efficiency of T. brassicae and T. embryophagum in combination with bacterial suspension of B. thuringiensis against the tomato leafminer T. absoluta eggs in cage inside greenhouse (semi field) experiments. Four treatments were used (T. brassicae or T. embryophagum + T. absoluta) (T1), (B. thuringiensis + T. absoluta) (T2), (T. brassicae or T. embryophagum + B. thuringiensis + T. absoluta) (T3) and control (T4). The lowest number of T. absoluta mines (6.1, 0.5 mine per plant) were recorded in T3 for T. brassicae and T. embryophagum were significantly lower than those of all other treatments which were followed by T1 and T2, while the highest number of mines per plant (50.70) were recorded in control (T4). In addition, the parasitism rate, adults’ emergence, the number of females and adult longevity of two parasitoids were investigated. According to the obtained results, the highest parasitism rate was obtained for T. embryophagum when treated with Bt reared in the T. absoluta eggs (31.18%). However, no significant differences were detected between T. brassicae and T. embryophagum in mortality and adult emergence rates were found when they were treated with/ without Bt reared in the T. absoluta eggs in cage inside greenhouse. Also, the longevity of T. embryophagum was significantly better than T. brassicae p = 0.000. This is the first study to investigate T. embryophagum in cage inside greenhouse for parasitizing the eggs of T. absoluta and results of present study suggested that T. embryophagum with Bt could be more efficient for biocontrol of T. absoluta.展开更多
Assessment of quality of biological control agents is an important step for the success of any biocontrol program.Experiments were carried out to select candidate Trichogramma species for use in biological control of ...Assessment of quality of biological control agents is an important step for the success of any biocontrol program.Experiments were carried out to select candidate Trichogramma species for use in biological control of the olive moth Prays oleae Bern(Lepidoptera,Yponomeutidae).Thirteen local strains were preselected on the basis of the geographical origin and the availability from mass production of the rearing host Ephestia kuehniella ZELL.(Lepidoptera,Pyralidae) under laboratory conditions.Selection tests were focusing on acceptance and preference for P.oleae eggs.In the acceptance test,a single parasitoid female was offered P.oleae eggs on "tricho-card" for 6 hours at 25°C,70% HR and L16:D9 and assessed for parasitism after 6 days.The preference was determined by offering the choice and observing contacts with eggs of the target pest P.oleae and eggs of the host E.kuehniella.Parasitism was therefore assessed 6 days after the experiment under similar laboratory conditions.In host acceptance test,most eggs of P.oleae were parasited by strains belonging to the species T.oleae,T.bourarachae and T.cacoeciae.These strains also showed a high number of contacts with olive moth eggs in preference tests.However,a small number of T.bourarachae observed ovipositions resulted in successful parasitism.Therefore,T.oleae and T.cacoeciae were selected as candidates for further experiments.展开更多
This study used Trichogramma japonicumto to control Chilo suppressalis (Walker) and Cnaphalocrocis medinalis(Guenée), and tested the effects of different control methods on main rice pests, natural enemies an...This study used Trichogramma japonicumto to control Chilo suppressalis (Walker) and Cnaphalocrocis medinalis(Guenée), and tested the effects of different control methods on main rice pests, natural enemies and rice yield. The results revealed that the parasitism of Trichogramma japonicum in the eggs of Chilo suppressalis (Walker) and Cnaphalocrocis medinalis (Guenée) reached 60.3% and 57.1%, and the control efficacy was up to 70.8 % and 91.99%, respectively. The control efficacy for Cnaphalocrocis medinalis (Guenée) was much better. This biological control method could be equivalent to chemical control method in the control effects on main pests in rice. The yield under the biological control was 26.5% higher than that of the control group, and the biological control had a signifcant increase in the number of natural enemies such as spider, up to 400 per 100 plants. Therefore, the sustainable prevention and control were achieved in the presentence with natural enemy organism.展开更多
Efficacy of the egg parasitoid, Trichogramma evanescens and the bio-pesticide bacteria, Bacillus thuringiensis kurstaki (Btk) in reduction of lesser date moth, Batrachedra amydraula infestations were studied during ...Efficacy of the egg parasitoid, Trichogramma evanescens and the bio-pesticide bacteria, Bacillus thuringiensis kurstaki (Btk) in reduction of lesser date moth, Batrachedra amydraula infestations were studied during seasons of 2011 and 2012. The result of 2011 showed that the release of egg parasitoid by rate of 500 and 1,000 parasitoids/palm tree achieved 55.06% and 67.45% reduction in infestation percentage, respectively. Meanwhile high reduction in infestation was achieved by Btk (78.65%) at dose rate of 6 g Btk powder/kg talc powder. The result of 2012 showed that the highest control efficacy (58.78%) was achieved at the first time of the control process, using Btk at dose rate of 6 g/kg talc powder. This result was not different significantly from the release of egg parasitoid by rate of 1,000 parasitoids/palm tree which achieved 53% reduction in infestation percentage. At the second time (after one week from the first application), the efficacy of Btk at dose rate of 6g/kg talc powder was increased to 78.78%, which differ significantly with the release of egg parasitoid by the same rate of 1,000 parasitoids/palm tree, having 61.79% efficacy. Reapplication of the control method achieved an increase in efficacy of the control agents, such increase was significant for both the release of the parasitoid at rate of 1,000/palm tree and for Btk at a dose of 6 g/kg talc powder.展开更多
The research cxamined the effects of microbial and novel insecticidal control strategies and also Irichogramma pretiosum on the I,epidoptera: Crambidae, the European corn borer (ECB), (Ostrinia nubilalis). The tr...The research cxamined the effects of microbial and novel insecticidal control strategies and also Irichogramma pretiosum on the I,epidoptera: Crambidae, the European corn borer (ECB), (Ostrinia nubilalis). The treatments included ~ino^d, from bacteria the entomopathogenic fungus Beauveria bassiana, the egg parasitoid Trichogramma pretiosum, and foliar applied Bt spray, and t^vo combinations Bearveria bassiana plus Bt spray and Trichogramma pretiosum and spinosad. The infestations by the European corn borer larvae on stalks of corn were very" severe in all the control treatments both 2006 and 2007. The microbial treatments caused various levels of European corn borer mortality. In all the parameters there was a significant difference between the control and other treatments with a P 〈 0.00 l. In this research, treatment with spinosad emerged as the most effective biological agent in the control of the European corn borer. The treatments had no significant effects on the relative abundance and composition of non-target arthropods (P 〉 0.05). This research is relevant in boosting underutilized control strategies and increasing stakeholder adoption of integrated pest management practices and thereby' reducing the use of conventional insecticides especially for orgamc thrmers. This is very important especially in certain countries where the commumities are skeptical about consuming transgenic crops.展开更多
文摘Wolbachia is a symbiotic bacterium that alters reproductive behavior of numerous arthropods. It is the most advanced way to study phytogeny and classification based on sequences of the wsp gene. The presence of Wolbachia in a lab strain of the thelytokous Trichogramma cacoeciae was firstly identified based on amplification and sequencing part of the wsp gene. Aligned the resulting sequence with the published ones, the phylogenetic relationships among Wolbachia which was found in T. cacoeciae, T. dendrolimi and other insects were established. The Wolbachia that found in T. cacoeciae and in T. dendrolimi belong to the Kue group and the Pip group, respectively.
基金supported by the National Natural Sci-ence Foundation of China (39770513)the Coop-erative Research Project between the National Crop Ex-periment Station, Rural Development Administration,Republic of Korea and the Institute of Plant Protection,Chinese Academy of Agricultural Sciences, China
文摘Intercropping maize with the prostrate variety of mungbean, Vigna radiata (L.) Wilczek which grows flat along the ground can increase parasitism of the eggs of the Asian corn borer, Ostrinia furnacalis (Guenée), a crucial insect pest of maize in China, by Trichogramma ostriniae Pang Chen. This study investigated the behavioural responses of T. ostriniae to plant volatiles emitted from whole plants, leaves, and flowers of prostrate and erect varieties of mungbean in a 4-armed olfactometer. Female parasitiods were significantly attracted to the odours from some varieties of prostrate mungbean when the visit duration and the number of visits were considered, but were not attracted to the odours from any erect varieties. The attractive odours were shown to emanate from the leaves, rather than from the flowers of prostrate mungbean plants. These results have implications for the augmentation of Trichogramma parasitoids in bio-control of O. furnacalis and other crop pests.
基金The National public service sectors (agriculture) research special (201103002)
文摘The results of evaluation on field control efficacy of Trichogramma dendrolimi against Ostrinia furnacalis showed that the correction rates of Ostrinia furnacalis egg mass parasitism were 71.75% and 73.57%,the average control effect were 65.85% and 70.24%,the restoration yield loss rates were 6.78% and 7.97%,input-output ratio at 1:27.8 and 1:33.5 in Longjiang county of Heilongjiang province in 2009 and 2010,respectively.The technology is a integration of advanced,practical,environmental safety,effective biocontrol measures,embodies the "public plant protection,green plant protection" fully,has significant economic,social and ecological benefits.
文摘The technology based on specific PCR amplification using internal transcribed spacer 2 of nuclear ribosomal DNA for molecular identification and detection of Trichogramma species was studied. Firstly the ITS2s of six Trichogramma species were cloned and sequenced, and the interspecific sequence variation was analyzed. Secondly the ITS2 regions of six geographical populations of T. dendrolimi were cloned and sequenced, and the intraspecific sequence identity was analyzed. The results show that the interspecific variation and intraspecific similarity of ITS2 sequences are very suitable for designation of specific primers at species-level. Screening of specific primers for T. dendrolimi leads to final sensitive and stable diagnostic primers. This system lets non-specialists can not only identify adults (males and females), but also identify eggs in parasitized hosts rapidly and accurately, which is impossible by conventional methods. Further development of this protocol can create a complete set of specific primers for different species of the whole genus Trichogramma .
文摘This study investigated the direct effect of the insecticides deltamethrin and spinosad on three egg parasitoids species: Trichogramma oleae, T. cacoeciae and T. bourarachae. The parasitoid pupae were exposed to pesticide residues on fresh olive tree leaves at recommended concentrations (RC) at different time intervals: 3, 10, 17, 24 and 31 days after pesticide applications. Parasitism viability (% emergence from parasitized eggs) and adult emergence time (developmental time from pupa to adult emergence) were evaluated. Regarding to the International Organization of Biological Control (IOBC) guidelines, results of toxicity effects of insecticides show that: Deltamethrin was moderately harmful to all Trichogramma species at RC (Decis®100 milliliters·ha−1), however, spinosad was harmless to moderately harmful at RC (Tracer®20 milliliters·ha−1). Trichogramma species revealed differences with regard to adult emergence time and exhibited significant changes in parasitism viability with increasing time after pesticide treatment. While deltamethrin residues affected parasitism viability 31 days after the product application, spinosad displayed similar viability for almost species 24 days after the application. The usefulness of Trichogramma parasitoids used as biological control agents, in olive tree ecosystem, was discussed in integrated pest management programs for Prays oleae control when parasitoid species were exposed during pupal stage to the insecticide residue.
文摘In this study, we investigated the efficiency of T. brassicae and T. embryophagum in combination with bacterial suspension of B. thuringiensis against the tomato leafminer T. absoluta eggs in cage inside greenhouse (semi field) experiments. Four treatments were used (T. brassicae or T. embryophagum + T. absoluta) (T1), (B. thuringiensis + T. absoluta) (T2), (T. brassicae or T. embryophagum + B. thuringiensis + T. absoluta) (T3) and control (T4). The lowest number of T. absoluta mines (6.1, 0.5 mine per plant) were recorded in T3 for T. brassicae and T. embryophagum were significantly lower than those of all other treatments which were followed by T1 and T2, while the highest number of mines per plant (50.70) were recorded in control (T4). In addition, the parasitism rate, adults’ emergence, the number of females and adult longevity of two parasitoids were investigated. According to the obtained results, the highest parasitism rate was obtained for T. embryophagum when treated with Bt reared in the T. absoluta eggs (31.18%). However, no significant differences were detected between T. brassicae and T. embryophagum in mortality and adult emergence rates were found when they were treated with/ without Bt reared in the T. absoluta eggs in cage inside greenhouse. Also, the longevity of T. embryophagum was significantly better than T. brassicae p = 0.000. This is the first study to investigate T. embryophagum in cage inside greenhouse for parasitizing the eggs of T. absoluta and results of present study suggested that T. embryophagum with Bt could be more efficient for biocontrol of T. absoluta.
基金INCODEV (TRIPHELIO) (UE/ 2002-2005) :Sustainable Control of Lepidopterous Pests in Olive Groves - Integration of Egg Parasitoids and Pheromones
文摘Assessment of quality of biological control agents is an important step for the success of any biocontrol program.Experiments were carried out to select candidate Trichogramma species for use in biological control of the olive moth Prays oleae Bern(Lepidoptera,Yponomeutidae).Thirteen local strains were preselected on the basis of the geographical origin and the availability from mass production of the rearing host Ephestia kuehniella ZELL.(Lepidoptera,Pyralidae) under laboratory conditions.Selection tests were focusing on acceptance and preference for P.oleae eggs.In the acceptance test,a single parasitoid female was offered P.oleae eggs on "tricho-card" for 6 hours at 25°C,70% HR and L16:D9 and assessed for parasitism after 6 days.The preference was determined by offering the choice and observing contacts with eggs of the target pest P.oleae and eggs of the host E.kuehniella.Parasitism was therefore assessed 6 days after the experiment under similar laboratory conditions.In host acceptance test,most eggs of P.oleae were parasited by strains belonging to the species T.oleae,T.bourarachae and T.cacoeciae.These strains also showed a high number of contacts with olive moth eggs in preference tests.However,a small number of T.bourarachae observed ovipositions resulted in successful parasitism.Therefore,T.oleae and T.cacoeciae were selected as candidates for further experiments.
文摘This study used Trichogramma japonicumto to control Chilo suppressalis (Walker) and Cnaphalocrocis medinalis(Guenée), and tested the effects of different control methods on main rice pests, natural enemies and rice yield. The results revealed that the parasitism of Trichogramma japonicum in the eggs of Chilo suppressalis (Walker) and Cnaphalocrocis medinalis (Guenée) reached 60.3% and 57.1%, and the control efficacy was up to 70.8 % and 91.99%, respectively. The control efficacy for Cnaphalocrocis medinalis (Guenée) was much better. This biological control method could be equivalent to chemical control method in the control effects on main pests in rice. The yield under the biological control was 26.5% higher than that of the control group, and the biological control had a signifcant increase in the number of natural enemies such as spider, up to 400 per 100 plants. Therefore, the sustainable prevention and control were achieved in the presentence with natural enemy organism.
文摘Efficacy of the egg parasitoid, Trichogramma evanescens and the bio-pesticide bacteria, Bacillus thuringiensis kurstaki (Btk) in reduction of lesser date moth, Batrachedra amydraula infestations were studied during seasons of 2011 and 2012. The result of 2011 showed that the release of egg parasitoid by rate of 500 and 1,000 parasitoids/palm tree achieved 55.06% and 67.45% reduction in infestation percentage, respectively. Meanwhile high reduction in infestation was achieved by Btk (78.65%) at dose rate of 6 g Btk powder/kg talc powder. The result of 2012 showed that the highest control efficacy (58.78%) was achieved at the first time of the control process, using Btk at dose rate of 6 g/kg talc powder. This result was not different significantly from the release of egg parasitoid by rate of 1,000 parasitoids/palm tree which achieved 53% reduction in infestation percentage. At the second time (after one week from the first application), the efficacy of Btk at dose rate of 6g/kg talc powder was increased to 78.78%, which differ significantly with the release of egg parasitoid by the same rate of 1,000 parasitoids/palm tree, having 61.79% efficacy. Reapplication of the control method achieved an increase in efficacy of the control agents, such increase was significant for both the release of the parasitoid at rate of 1,000/palm tree and for Btk at a dose of 6 g/kg talc powder.
文摘The research cxamined the effects of microbial and novel insecticidal control strategies and also Irichogramma pretiosum on the I,epidoptera: Crambidae, the European corn borer (ECB), (Ostrinia nubilalis). The treatments included ~ino^d, from bacteria the entomopathogenic fungus Beauveria bassiana, the egg parasitoid Trichogramma pretiosum, and foliar applied Bt spray, and t^vo combinations Bearveria bassiana plus Bt spray and Trichogramma pretiosum and spinosad. The infestations by the European corn borer larvae on stalks of corn were very" severe in all the control treatments both 2006 and 2007. The microbial treatments caused various levels of European corn borer mortality. In all the parameters there was a significant difference between the control and other treatments with a P 〈 0.00 l. In this research, treatment with spinosad emerged as the most effective biological agent in the control of the European corn borer. The treatments had no significant effects on the relative abundance and composition of non-target arthropods (P 〉 0.05). This research is relevant in boosting underutilized control strategies and increasing stakeholder adoption of integrated pest management practices and thereby' reducing the use of conventional insecticides especially for orgamc thrmers. This is very important especially in certain countries where the commumities are skeptical about consuming transgenic crops.