Bt corn “MON810: Ajeeb YG” produces delta endotoxins in the whole plant due to the genetic modification process. The chemical analysis of this variety showed significant differences from its conventional counterpart...Bt corn “MON810: Ajeeb YG” produces delta endotoxins in the whole plant due to the genetic modification process. The chemical analysis of this variety showed significant differences from its conventional counterpart “Ajeeb”. Further, feeding studies on rats were designed to complete assessing the safety of “MON810: Ajeeb YG”. Three groups of rats (6 males and 6 females’ rats/group) were fed on control diet, non-Bt corn and Bt corn for 1.5 months and 3 months. After 1.5 months, 3 males and 3 females from each group were sacrificed, and after another 1.5 months, 3 males and 3 females from each group and their offspring were sacrificed. Histopathological examination, blood haematology and serum biochemical analysis were determined. Results indicated significant differences among the tested parameters in the three groups especially Bt group. Severe changes in the liver of Bt group after 3 months were observed.展开更多
Two variants of diet composition were prepared to evaluate the susceptibility of ECBs to CrylAb toxin as follows： 1） 38-0600 Stonefly Heliothis Diet mixed with purified CrylAb protein and 2） 38-0600 Stonefly Heliot...Two variants of diet composition were prepared to evaluate the susceptibility of ECBs to CrylAb toxin as follows： 1） 38-0600 Stonefly Heliothis Diet mixed with purified CrylAb protein and 2） 38-0600 Stonefly Heliothis Diet mixed with lyophylized leaves of Bt maize MON 810-YieldGard. A method of sample preparation and extraction of Bt toxin for reproducible ELISA quantification were optimized. The qualitative DAS-ELISA kit from Agdia was optimized for use in quantitative analysis of Cry lAb toxin. The mortality of ECB larvae from the laboratory strain on the diet with CrylAb toxin did not differ significantly from the mortality on the diet with Bt maize leaves with the same rate of Cry lAb toxin. Similarly, the mortality of the ECB larvae from the field population on the diet with Bt maize leaves did not differ significantly from the mortality of ECB larvae from the laboratory strain on the same type of diet. Therefore, the incorporation of Bt maize leaves into the diet did not influence the efficacy of CrylAb toxin against ECBs. Using this method, a susceptibility of one field population of ECBs from the Czech Republic to CrylAb toxin was determined （LC50 of 2.16 μg of Cry 1Ab g^-1 of diet）.展开更多
Unintended effects of genetic modification on chemical composition of Bt maize leaf litter may have impacts on its decomposition. In most agricultural systems in South Africa, maize litter is either left on the soil s...Unintended effects of genetic modification on chemical composition of Bt maize leaf litter may have impacts on its decomposition. In most agricultural systems in South Africa, maize litter is either left on the soil surface or incorporated into the soil during tillage. A litterbag experiment, using leaf litter of three maize hybrids （DKC80-12B, DKC80-10 and DKC6-125）, was carried out at the University of Fort Hare Research Farm, South Africa, to determine the effects of genetic modification on decomposition of maize leaf litter when left on the soil surface under field conditions between July and November, the normal fallow period, in 2008. Another litterbag experiment was conducted at the University of Fort Hare Research Farm and Zanyokwe Irrigation Scheme, South Africa, using leaf ~itter of two maize hybrids genetically modified with the erylAb gene （MONS10）, DKC75-15B and PAN6Q-3OSB, and their corresponding near isolines, CRN3505 and PAN6Q-121. The degradation of CrylAb protein in the litter, both surface-applied and soil-incorporated, was also investigated. Decomposition of Bt maize litter was similar to that of non-Bt maize litter both when applied on the surface and when incorporated into soil. Soil-incorporated litter, as well as its CrylAb protein, decomposed faster than that applied on the surface. The leaf litter C：N ratios of PAN6Q-308B and PAN6Q-121 were similar throughout the study, whereas those of DKC75-15B and CRN3505 declined by similar amounts during a 12-week period. These findings suggested that decomposition of leaf litter of Bt maize, with the MON810 event, was not affected by maize genetic modification, and that the CrylAb protein broke down together with plant leaf litter during the winter fallow regardless of whether the litter was applied on the soil surface or incorporated into soil.展开更多
The cultivation of CrylAb-expressing genetically modified MON810 （Bt maize） has led to public concern in Europe, regarding its impact on nontarget arthro- pods （NTAs）. We have assessed the potential effects of DKC...The cultivation of CrylAb-expressing genetically modified MON810 （Bt maize） has led to public concern in Europe, regarding its impact on nontarget arthro- pods （NTAs）. We have assessed the potential effects of DKC 6451 YG （MON810） maize on canopy NTAs in a farm-scale study performed in Central Spain during 3 years. The study focused on hemipteran herbivores （leafhoppers and planthoppers） and hymenopteran parasitic wasps （mymarids） collected by yellow sticky traps, which accounted for 72% of the total number of insects studied. The dynamics and abundance of these groups varied among years, but no significant differences were found between Bt and non-Bt maize, indicating that Bt maize had no negative effect on these taxa. Nonetheless, the CrylAb toxin was detected in 2 different arthropods collected from Bt maize foliage, the cicadellids Zyginidia scutellaris and Empoasca spp. A retrospective power analysis on the arthropod abundance data for our field trials has determined that Z. scutellaris and the family My- maridae have high capacity to detect differences between the Bt maize and its isogenic counterpart. The use of these canopy NTAs as surrogates for assessing environmental impacts of Bt maize is discussed.展开更多
文摘Bt corn “MON810: Ajeeb YG” produces delta endotoxins in the whole plant due to the genetic modification process. The chemical analysis of this variety showed significant differences from its conventional counterpart “Ajeeb”. Further, feeding studies on rats were designed to complete assessing the safety of “MON810: Ajeeb YG”. Three groups of rats (6 males and 6 females’ rats/group) were fed on control diet, non-Bt corn and Bt corn for 1.5 months and 3 months. After 1.5 months, 3 males and 3 females from each group were sacrificed, and after another 1.5 months, 3 males and 3 females from each group and their offspring were sacrificed. Histopathological examination, blood haematology and serum biochemical analysis were determined. Results indicated significant differences among the tested parameters in the three groups especially Bt group. Severe changes in the liver of Bt group after 3 months were observed.
文摘Two variants of diet composition were prepared to evaluate the susceptibility of ECBs to CrylAb toxin as follows： 1） 38-0600 Stonefly Heliothis Diet mixed with purified CrylAb protein and 2） 38-0600 Stonefly Heliothis Diet mixed with lyophylized leaves of Bt maize MON 810-YieldGard. A method of sample preparation and extraction of Bt toxin for reproducible ELISA quantification were optimized. The qualitative DAS-ELISA kit from Agdia was optimized for use in quantitative analysis of Cry lAb toxin. The mortality of ECB larvae from the laboratory strain on the diet with CrylAb toxin did not differ significantly from the mortality on the diet with Bt maize leaves with the same rate of Cry lAb toxin. Similarly, the mortality of the ECB larvae from the field population on the diet with Bt maize leaves did not differ significantly from the mortality of ECB larvae from the laboratory strain on the same type of diet. Therefore, the incorporation of Bt maize leaves into the diet did not influence the efficacy of CrylAb toxin against ECBs. Using this method, a susceptibility of one field population of ECBs from the Czech Republic to CrylAb toxin was determined （LC50 of 2.16 μg of Cry 1Ab g^-1 of diet）.
基金Supported by the National Research Foundation of South Africa(NRF)the Govan Mbeki Research and Development Center(GMRDC)of the University of Fort Hare(No.GUN62299)
文摘Unintended effects of genetic modification on chemical composition of Bt maize leaf litter may have impacts on its decomposition. In most agricultural systems in South Africa, maize litter is either left on the soil surface or incorporated into the soil during tillage. A litterbag experiment, using leaf litter of three maize hybrids （DKC80-12B, DKC80-10 and DKC6-125）, was carried out at the University of Fort Hare Research Farm, South Africa, to determine the effects of genetic modification on decomposition of maize leaf litter when left on the soil surface under field conditions between July and November, the normal fallow period, in 2008. Another litterbag experiment was conducted at the University of Fort Hare Research Farm and Zanyokwe Irrigation Scheme, South Africa, using leaf ~itter of two maize hybrids genetically modified with the erylAb gene （MONS10）, DKC75-15B and PAN6Q-3OSB, and their corresponding near isolines, CRN3505 and PAN6Q-121. The degradation of CrylAb protein in the litter, both surface-applied and soil-incorporated, was also investigated. Decomposition of Bt maize litter was similar to that of non-Bt maize litter both when applied on the surface and when incorporated into soil. Soil-incorporated litter, as well as its CrylAb protein, decomposed faster than that applied on the surface. The leaf litter C：N ratios of PAN6Q-308B and PAN6Q-121 were similar throughout the study, whereas those of DKC75-15B and CRN3505 declined by similar amounts during a 12-week period. These findings suggested that decomposition of leaf litter of Bt maize, with the MON810 event, was not affected by maize genetic modification, and that the CrylAb protein broke down together with plant leaf litter during the winter fallow regardless of whether the litter was applied on the soil surface or incorporated into soil.
文摘The cultivation of CrylAb-expressing genetically modified MON810 （Bt maize） has led to public concern in Europe, regarding its impact on nontarget arthro- pods （NTAs）. We have assessed the potential effects of DKC 6451 YG （MON810） maize on canopy NTAs in a farm-scale study performed in Central Spain during 3 years. The study focused on hemipteran herbivores （leafhoppers and planthoppers） and hymenopteran parasitic wasps （mymarids） collected by yellow sticky traps, which accounted for 72% of the total number of insects studied. The dynamics and abundance of these groups varied among years, but no significant differences were found between Bt and non-Bt maize, indicating that Bt maize had no negative effect on these taxa. Nonetheless, the CrylAb toxin was detected in 2 different arthropods collected from Bt maize foliage, the cicadellids Zyginidia scutellaris and Empoasca spp. A retrospective power analysis on the arthropod abundance data for our field trials has determined that Z. scutellaris and the family My- maridae have high capacity to detect differences between the Bt maize and its isogenic counterpart. The use of these canopy NTAs as surrogates for assessing environmental impacts of Bt maize is discussed.
