The Experts below are selected from a list of 303 Experts worldwide ranked by ideXlab platform
Ye Chen - One of the best experts on this subject based on the ideXlab platform.
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nematotoxicity of a cyt like protein Toxin from conidiobolus obscurus entomophthoromycotina on the pine wood nematode bursaphelenchus xylophilus
Pest Management Science, 2021Co-Authors: Xiang Zhou, Shani Chen, Kai Guo, Linlin Huang, Ye ChenAbstract:BACKGROUND The pine wood nematode Bursaphelenchus xylophilus is a destructive pest on Pinus trees and lacks effective control measures. The present study identified a novel nematotoxic cytolytic (Cyt)-like protein originating from the entomopathogenic fungus Conidiobolus obscurus. RESULTS The protein was successfully purified using heterologous expression in Escherichia coli and affinity chromatography. N-hydroxysuccinimide-rhodamine-labeled Cyt-like protein was used to establish the route of Toxin Uptake, and revealed that the Toxin can enter the nematode via the stylet. In bioassays, the purified protein had high nematicide activity against B. xylophilus, with a median lethal concentration at 24 h of 15.8 and 29.4 μg mL-1 for juveniles and adults, respectively. Compared with the deionized water control, fecundity, thrashing, and egg hatching were significantly reduced by 97%, 98%, and 83%, respectively, with 40 μg mL-1 Cyt-like protein at 24-36 h. Staining with Oil-Red-O showed a decrease in large lipid droplet formation in the protein-treated adult nematodes. CONCLUSION The Cyt-like protein Toxin possesses high nematicide activity against B. xylophilus with effects on nematode vitality and fecundity. The potential exists to use the Cyt-like protein for the control of B. xylophilus.
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Nematotoxicity of a Cyt‐like protein Toxin from Conidiobolus obscurus (Entomophthoromycotina) on the pine wood nematode Bursaphelenchus xylophilus
Pest management science, 2020Co-Authors: Xiang Zhou, Shani Chen, Kai Guo, Linlin Huang, Ye ChenAbstract:BACKGROUND The pine wood nematode Bursaphelenchus xylophilus is a destructive pest on Pinus trees and lacks effective control measures. The present study identified a novel nematotoxic cytolytic (Cyt)-like protein originating from the entomopathogenic fungus Conidiobolus obscurus. RESULTS The protein was successfully purified using heterologous expression in Escherichia coli and affinity chromatography. N-hydroxysuccinimide-rhodamine-labeled Cyt-like protein was used to establish the route of Toxin Uptake, and revealed that the Toxin can enter the nematode via the stylet. In bioassays, the purified protein had high nematicide activity against B. xylophilus, with a median lethal concentration at 24 h of 15.8 and 29.4 μg mL-1 for juveniles and adults, respectively. Compared with the deionized water control, fecundity, thrashing, and egg hatching were significantly reduced by 97%, 98%, and 83%, respectively, with 40 μg mL-1 Cyt-like protein at 24-36 h. Staining with Oil-Red-O showed a decrease in large lipid droplet formation in the protein-treated adult nematodes. CONCLUSION The Cyt-like protein Toxin possesses high nematicide activity against B. xylophilus with effects on nematode vitality and fecundity. The potential exists to use the Cyt-like protein for the control of B. xylophilus.
Alberto Lanzoni - One of the best experts on this subject based on the ideXlab platform.
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Bt-Toxin Uptake by the non-target herbivore, Myzus persicae (Hemiptera: Aphididae), feeding on transgenic oilseed rape in laboratory conditions.
Bulletin of entomological research, 2010Co-Authors: Giovanni Burgio, Giovanni Dinelli, Ilaria Marotti, Michela Zurla, Sara Bosi, Alberto LanzoniAbstract:The potential non-target effects of genetically modified crops are some of the more debated topics within applied biotechnologies in agriculture and environmental risk assessment. The objective of the present research was to study the potential Bt-Toxin Uptake by the non-target herbivore Myzus persicae Sulzer (Hemiptera: Aphididae) feeding on transgenic oilseed rape plants (Brassica napus cv. 'Westar' lines GT 2-4) expressing the Cry1Ac endoToxin. A specific aim was to replicate our previous experiment in controlled laboratory conditions to avoid or minimize the risk of contamination leading to potential false positive results. The Toxin levels in vernalized (V) and not-vernalized (not-V) transgenic oilseed rape plants was also monitored to better clarify the role of physiological processes on Bt-Toxin expression. Cry1Ac expression in not-V plants (mean concentration±SE=167.8±5.7 μg kg-1 FW) showed a pattern of large variability, in comparison with V plants whose expression (mean concentration±SE=227.7±1.9 μg kg-1 FW) was significantly more stable. Cry1Ac Toxin was detected in three aphid samples reared on V plants with a mean Toxin concentration±SE of 4.8±0.6 μg Kg-1 FW and in three out of six samples of aphids reared on not-V plants (mean Toxin concentration±SE=7.1±1.2 μg kg-1 FW). The mean Bt-Toxin concentration of all the positive aphid samples was 5.9±1.0 μg kg-1 FW. Our results confirmed the findings of our previous experiment and highlighted the potential for Cry1Ac Toxin Uptake by aphids feeding on transgenic oilseed rape plants.
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Evaluation of Bt-Toxin Uptake by the non-target herbivore, Myzus persicae (Hemiptera: Aphididae), feeding on transgenic oilseed rape.
Bulletin of entomological research, 2007Co-Authors: Giovanni Burgio, Giovanni Dinelli, Ilaria Marotti, Alberto Lanzoni, Gianumberto Accinelli, Alessandra Bonetti, Fabio RamilliAbstract:As consequence of the concern about the biosafety of genetically modified plants, biological and ecological studies are considered crucial for environmental risk assessment. Laboratory experiments were carried out in order to evaluate the transfer of the Cry1Ac Bt-Toxin from a transgenic Bt-oilseed rape to a non-target pest, Myzus persicae Sulzer. Cry1Ac protein levels in plants and aphids were determined using a double sandwich enzyme-linked immunosorbent assay. Phloem sap from (Bt+) and (Btx) oilseed rape plants was collected from leaves using a standard method of extraction in an EDTA buffer. Bt-Toxin was present in phloem sap, with a mean concentration of 2.7+1.46 ppb, corresponding to a 24-fold lower level than in oilseed rape leaves. Toxin was also detected in aphid samples, with a mean concentration in the positive samples of 2.0+0.8 ppb. The evidence that Bt-Toxin remains in herbivores, in this case an aphid, could be useful to clarify functional aspects linked to possible consequences of Bt-crops on food chains involving herbivore‐natural enemy trophic systems. Further studies are needed in order to improve the knowledge on the functional aspects linked to the transfer of the Cry1Ac Bt-Toxin from GM-oilseed rape to aphids and their possible consequence.
Giovanni Burgio - One of the best experts on this subject based on the ideXlab platform.
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Bt-Toxin Uptake by the non-target herbivore, Myzus persicae (Hemiptera: Aphididae), feeding on transgenic oilseed rape in laboratory conditions.
Bulletin of entomological research, 2010Co-Authors: Giovanni Burgio, Giovanni Dinelli, Ilaria Marotti, Michela Zurla, Sara Bosi, Alberto LanzoniAbstract:The potential non-target effects of genetically modified crops are some of the more debated topics within applied biotechnologies in agriculture and environmental risk assessment. The objective of the present research was to study the potential Bt-Toxin Uptake by the non-target herbivore Myzus persicae Sulzer (Hemiptera: Aphididae) feeding on transgenic oilseed rape plants (Brassica napus cv. 'Westar' lines GT 2-4) expressing the Cry1Ac endoToxin. A specific aim was to replicate our previous experiment in controlled laboratory conditions to avoid or minimize the risk of contamination leading to potential false positive results. The Toxin levels in vernalized (V) and not-vernalized (not-V) transgenic oilseed rape plants was also monitored to better clarify the role of physiological processes on Bt-Toxin expression. Cry1Ac expression in not-V plants (mean concentration±SE=167.8±5.7 μg kg-1 FW) showed a pattern of large variability, in comparison with V plants whose expression (mean concentration±SE=227.7±1.9 μg kg-1 FW) was significantly more stable. Cry1Ac Toxin was detected in three aphid samples reared on V plants with a mean Toxin concentration±SE of 4.8±0.6 μg Kg-1 FW and in three out of six samples of aphids reared on not-V plants (mean Toxin concentration±SE=7.1±1.2 μg kg-1 FW). The mean Bt-Toxin concentration of all the positive aphid samples was 5.9±1.0 μg kg-1 FW. Our results confirmed the findings of our previous experiment and highlighted the potential for Cry1Ac Toxin Uptake by aphids feeding on transgenic oilseed rape plants.
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Evaluation of Bt-Toxin Uptake by the non-target herbivore, Myzus persicae (Hemiptera: Aphididae), feeding on transgenic oilseed rape.
Bulletin of entomological research, 2007Co-Authors: Giovanni Burgio, Giovanni Dinelli, Ilaria Marotti, Alberto Lanzoni, Gianumberto Accinelli, Alessandra Bonetti, Fabio RamilliAbstract:As consequence of the concern about the biosafety of genetically modified plants, biological and ecological studies are considered crucial for environmental risk assessment. Laboratory experiments were carried out in order to evaluate the transfer of the Cry1Ac Bt-Toxin from a transgenic Bt-oilseed rape to a non-target pest, Myzus persicae Sulzer. Cry1Ac protein levels in plants and aphids were determined using a double sandwich enzyme-linked immunosorbent assay. Phloem sap from (Bt+) and (Btx) oilseed rape plants was collected from leaves using a standard method of extraction in an EDTA buffer. Bt-Toxin was present in phloem sap, with a mean concentration of 2.7+1.46 ppb, corresponding to a 24-fold lower level than in oilseed rape leaves. Toxin was also detected in aphid samples, with a mean concentration in the positive samples of 2.0+0.8 ppb. The evidence that Bt-Toxin remains in herbivores, in this case an aphid, could be useful to clarify functional aspects linked to possible consequences of Bt-crops on food chains involving herbivore‐natural enemy trophic systems. Further studies are needed in order to improve the knowledge on the functional aspects linked to the transfer of the Cry1Ac Bt-Toxin from GM-oilseed rape to aphids and their possible consequence.
Jacques Hille - One of the best experts on this subject based on the ideXlab platform.
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Tomato susceptibility to Alternaria stem canker: Parameters involved in host-specific Toxin-induced leaf necrosis
2016Co-Authors: Hanneke M.a. Witsenboer, Karen M. Kloosterziel, Guus Hateboer, H. John, J. Nijkamp, Jacques HilleAbstract:AAL-Toxin causes severe necrosis in leaves of susceptible tomato cultivars at nanomolar concentrations. In resistant omato cultivars harbouring the semi-dominant Alternaria stem canker resistance locus necrosis is also observed, however at much higher Toxin concentrations, in both lines the percentage of the leaf area exhibiting necrosis is dependent on Toxin concentration and on length of Toxin exposure. However, at the same Toxin concentration, periods of Toxin exposure resulting in similar necrosis are much longer for the resistant than for the susceptible tomato. It was demonstrated that Toxin Uptake in the leaves does not imply Toxin Uptake in the cells since a discrepancy was observed between death of protoplasts, isolated from leaves cut for protoplast isolation immediately after incubation on AAL-Toxin and necrosis in leaves when further incubated on water. However. when after exposure to AAL-Toxin leaves were further incubated on water for 24 h before they were cut for protoplast isolation, a correlation was found between leaf necrosis and death of protoplasts. This suggests that further transport is needed in leaves after Toxin Uptake, bringing Toxin to all the cells, that cannot occur in leaves cut for protoplast isolation. Light plays an important role in AAL-Toxin induced necrosis and it was shown that length of light exposure controls necrosis development like Toxin concentration and length of Toxin exposure. The product of these 3 parameters can provide a good hint to predict he extent of leaf necrosis. The effect of light might be restricted to differentiated leaf tissue, since it was not observed in callus tissue. Key words: Alternaria alternata f.sp. lycopersici; host specific Toxin; tomato; leaf necrosis development; resistance mechanis
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Tomato susceptibility to Alternaria stem canker: Parameters involved in host-specific Toxin-induced leaf necrosis
Plant Science, 1992Co-Authors: Hanneke M.a. Witsenboer, Karen M. Kloosterziel, Guus Hateboer, H. John J. Nijkamp, Jacques HilleAbstract:Abstract AAL-Toxin causes severe necrosis in leaves of susceptible tomato cultivars at nanomolar concentrations. In resistant tomato cultivars harbouring the semi-dominant Alternaria stem canker resistance locus necrosis is also observed, however at much higher Toxin concentrations. In both lines the percentage of the leaf area exhibiting necrosis is dependent on Toxin concentration and on length of Toxin exposure. However, at the same Toxin concentration, periods of Toxin exposure resulting in similar necrosis are much longer for the resistant than for the susceptible tomato. It was demonstrated that Toxin Uptake in the leaves does not imply Toxin Uptake in the cells since a discrepancy was observed between death of protoplasts, isolated from leaves cut for protoplast isolation immediately after incubation on AAL-Toxin and necrosis in leaves when further incubated on water. However, when after exposure to AAL-Toxin leaves were further incubated on water for 24 h before they were cut for protoplast isolation, a correlation was found between leaf necrosis and death of protoplasts. This suggests that further transport is needed in leaves after Toxin Uptake, bringing Toxin to all the cells, that cannot occur in leaves cut for protoplast isolation. Light plays an important role in AAL-Toxin induced necrosis and it was shown that length of light exposure controls necrosis development like Toxin concentration and length of Toxin exposure. The product of these 3 parameters can provide a good hint to predict the extent of leaf necrosis. The effect of light might be restricted to differentiated leaf tissue, since it was not observed in callus tissue.
Xiang Zhou - One of the best experts on this subject based on the ideXlab platform.
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nematotoxicity of a cyt like protein Toxin from conidiobolus obscurus entomophthoromycotina on the pine wood nematode bursaphelenchus xylophilus
Pest Management Science, 2021Co-Authors: Xiang Zhou, Shani Chen, Kai Guo, Linlin Huang, Ye ChenAbstract:BACKGROUND The pine wood nematode Bursaphelenchus xylophilus is a destructive pest on Pinus trees and lacks effective control measures. The present study identified a novel nematotoxic cytolytic (Cyt)-like protein originating from the entomopathogenic fungus Conidiobolus obscurus. RESULTS The protein was successfully purified using heterologous expression in Escherichia coli and affinity chromatography. N-hydroxysuccinimide-rhodamine-labeled Cyt-like protein was used to establish the route of Toxin Uptake, and revealed that the Toxin can enter the nematode via the stylet. In bioassays, the purified protein had high nematicide activity against B. xylophilus, with a median lethal concentration at 24 h of 15.8 and 29.4 μg mL-1 for juveniles and adults, respectively. Compared with the deionized water control, fecundity, thrashing, and egg hatching were significantly reduced by 97%, 98%, and 83%, respectively, with 40 μg mL-1 Cyt-like protein at 24-36 h. Staining with Oil-Red-O showed a decrease in large lipid droplet formation in the protein-treated adult nematodes. CONCLUSION The Cyt-like protein Toxin possesses high nematicide activity against B. xylophilus with effects on nematode vitality and fecundity. The potential exists to use the Cyt-like protein for the control of B. xylophilus.
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Nematotoxicity of a Cyt‐like protein Toxin from Conidiobolus obscurus (Entomophthoromycotina) on the pine wood nematode Bursaphelenchus xylophilus
Pest management science, 2020Co-Authors: Xiang Zhou, Shani Chen, Kai Guo, Linlin Huang, Ye ChenAbstract:BACKGROUND The pine wood nematode Bursaphelenchus xylophilus is a destructive pest on Pinus trees and lacks effective control measures. The present study identified a novel nematotoxic cytolytic (Cyt)-like protein originating from the entomopathogenic fungus Conidiobolus obscurus. RESULTS The protein was successfully purified using heterologous expression in Escherichia coli and affinity chromatography. N-hydroxysuccinimide-rhodamine-labeled Cyt-like protein was used to establish the route of Toxin Uptake, and revealed that the Toxin can enter the nematode via the stylet. In bioassays, the purified protein had high nematicide activity against B. xylophilus, with a median lethal concentration at 24 h of 15.8 and 29.4 μg mL-1 for juveniles and adults, respectively. Compared with the deionized water control, fecundity, thrashing, and egg hatching were significantly reduced by 97%, 98%, and 83%, respectively, with 40 μg mL-1 Cyt-like protein at 24-36 h. Staining with Oil-Red-O showed a decrease in large lipid droplet formation in the protein-treated adult nematodes. CONCLUSION The Cyt-like protein Toxin possesses high nematicide activity against B. xylophilus with effects on nematode vitality and fecundity. The potential exists to use the Cyt-like protein for the control of B. xylophilus.