Fusarium head blight caused by Fusarium graminearum is one of the most serious diseases in wheat production worldwide, which seriously affects the yield and quality of wheat. Wheat grains carrying the pathogen are poi...Fusarium head blight caused by Fusarium graminearum is one of the most serious diseases in wheat production worldwide, which seriously affects the yield and quality of wheat. Wheat grains carrying the pathogen are poisonous to human and livestock health. With the long-term use of single chemical pesticide, the drug-resistance of F. graminearum is increasing day by day, and mixed agent is one of the effective strategies to improve the efficacy and delay the resistance. The mycelial growth rate method was used to determine the inhibition rates of phenamacril, tebuconazole and their mixtures(1∶1, 1∶3, 1∶5, 1∶7, 3∶1, 5∶1 and 7∶1). The synergistic coefficient(SR) was calculated by Wadley method, and the combined action types of the two agents were evaluated. The results showed that the ECof tebuconazole was 0.418 28 mg/L, and that of phenamacril was 0.489 8 mg/L; the optimum mixture ratio of phenamacril and tebuconazole was 1 ∶1, with the ECvalue of 0.053 74 and the synergistic coefficient of 4.2696, and the control effect of mixed agent was significantly better than that of single agent. It is feasible to control Fusarium head blight by mixing phenamacril and tebuconazole, providing a theoretical basis for development of new compound agents and effective control of Fusarium head blight.展开更多
Precise and spatiotemporal control over the pesticide remains to be a challenge.More efficient controlled release systems(CRSs)have been developed to support the precise delivery of active ingredients.Herein,we incorp...Precise and spatiotemporal control over the pesticide remains to be a challenge.More efficient controlled release systems(CRSs)have been developed to support the precise delivery of active ingredients.Herein,we incorporated the photoremovable protecting groups(PRPGs)into phenamacril(PHE)and obtained two photo-responsive fungicides of NV-PHE and DEACM-PHE.The 4,5-dimethoxy-o-nitrobenzyl(NV)or 7-diethylaminocoumarin(DEACM)-caged PHE could release the active molecule PHE after irradiation of UV light and blue light,respectively.Optical properties and in-vitro/vivo fungicidal activities of NV-PHE and DEACM-PHE demonstrated the feasibility for light controlled release of PHE.DEACM-PHE could release 98%PHE by illumination of blue light.The irradiated DEACM-PHE could preserve the similar bioactivity of PHE,and significantly improve the in-vitro/vivo fungicidal activities compared to the non-irradiated DEACM-PHE.The optical controlled release of PHE from DEACM-PHE enabled the precise and spatiotemporal delivery of PHE,diversifying the development of CRSs for pesticide,and providing environmentfriendly agricultural applications with high pesticide efficiency.展开更多
基金Supported by Open Project Program of Engineering Research Center of Ecology and Agricultural Use of Wetland,the Ministry of Education(KF201802)
文摘Fusarium head blight caused by Fusarium graminearum is one of the most serious diseases in wheat production worldwide, which seriously affects the yield and quality of wheat. Wheat grains carrying the pathogen are poisonous to human and livestock health. With the long-term use of single chemical pesticide, the drug-resistance of F. graminearum is increasing day by day, and mixed agent is one of the effective strategies to improve the efficacy and delay the resistance. The mycelial growth rate method was used to determine the inhibition rates of phenamacril, tebuconazole and their mixtures(1∶1, 1∶3, 1∶5, 1∶7, 3∶1, 5∶1 and 7∶1). The synergistic coefficient(SR) was calculated by Wadley method, and the combined action types of the two agents were evaluated. The results showed that the ECof tebuconazole was 0.418 28 mg/L, and that of phenamacril was 0.489 8 mg/L; the optimum mixture ratio of phenamacril and tebuconazole was 1 ∶1, with the ECvalue of 0.053 74 and the synergistic coefficient of 4.2696, and the control effect of mixed agent was significantly better than that of single agent. It is feasible to control Fusarium head blight by mixing phenamacril and tebuconazole, providing a theoretical basis for development of new compound agents and effective control of Fusarium head blight.
基金This work was financially supported by the Natural Science Foundation of China(Nos.21877039,32072441)National Key Research and Development Program of China(No.2018YFD0200100)Innovation Program of Shanghai Municipal Education Commission(No.2017-01-07-00-02-E00037).
文摘Precise and spatiotemporal control over the pesticide remains to be a challenge.More efficient controlled release systems(CRSs)have been developed to support the precise delivery of active ingredients.Herein,we incorporated the photoremovable protecting groups(PRPGs)into phenamacril(PHE)and obtained two photo-responsive fungicides of NV-PHE and DEACM-PHE.The 4,5-dimethoxy-o-nitrobenzyl(NV)or 7-diethylaminocoumarin(DEACM)-caged PHE could release the active molecule PHE after irradiation of UV light and blue light,respectively.Optical properties and in-vitro/vivo fungicidal activities of NV-PHE and DEACM-PHE demonstrated the feasibility for light controlled release of PHE.DEACM-PHE could release 98%PHE by illumination of blue light.The irradiated DEACM-PHE could preserve the similar bioactivity of PHE,and significantly improve the in-vitro/vivo fungicidal activities compared to the non-irradiated DEACM-PHE.The optical controlled release of PHE from DEACM-PHE enabled the precise and spatiotemporal delivery of PHE,diversifying the development of CRSs for pesticide,and providing environmentfriendly agricultural applications with high pesticide efficiency.
