Wheat (Triticum aestivum L.) is grown throughout the winter time in Southern Brazil and turns out to be the main agricultural crop at such a year season in the State of Paraná. However, throughout the crop growin...Wheat (Triticum aestivum L.) is grown throughout the winter time in Southern Brazil and turns out to be the main agricultural crop at such a year season in the State of Paraná. However, throughout the crop growing season foliar diseases significantly compromise commercial yields in such a manner as to justify the application of fungicides at the right time to control foliar diseases in production fields. The aim of the current manuscript was to assess the impact of different timings for fungicide application (epoxiconazole + pyraclostrobin) on the control of leaf rust (Puccinia triticina E.) and yellow spot (Pyrenophora tritici-repentis) diseases in two wheat genotypes featured by distinct levels of susceptibility in Southern Brazil. A field trial was conducted in Ponta Grossa, State of Paraná, Brazil, in light of split plot statistical design at an experimental area belonging to CESCAGE. The following treatments were imposed in the current study: control (with no sprays);sprays at the first node, booting and heading;sprays at stem extension and flowering;sprays at booting and heading. Throughout the entire crop growing season, the control treatment was conducive to the highest severity levels for both diseases. The increasing of the area under the diseases progress curve assessed herein substantially impinged upon yield components of both wheat genotypes under scrutiny. In general, fungicide sprays at the first node did not culminate in economical advantages. The best timing for fungicide application was the one ascribed to booting and heading stages.展开更多
A comparison of sensitivity in extratropical circulation in the Northern Hemisphere （NH） and Southern Hemisphere （SH） is conducted through observational analyses and diagnostic linear model experiments for two typ...A comparison of sensitivity in extratropical circulation in the Northern Hemisphere （NH） and Southern Hemisphere （SH） is conducted through observational analyses and diagnostic linear model experiments for two types of El Ni（n）o events,the traditional El Ni（n）o with the strongest warmth in the eastern tropical Pacific （EP El Ni（n）o） and the El Ni（n）o Modoki with the strongest warmth in the central tropical Pacific （CP El Ni（n）o）.It is shown that CP El Ni（n）o favors the occurrence of a negative-phase Northern Annular Mode （NAM）,while EP El Ni（n）o favors that of the Pacific-North American （PNA） pattern.In SH,both EP and CP El Ni（n）o induce a negative phase Southern Annular Mode （SAM）.However,the former has a greater amplitude,which is consistent with the stronger sea surface temperature （SST） warmth.The difference in the two types of El Ni（n）o events in NH may originate from the dependence of heating-induced extratropical response on the location of initial heating,which may be associated with activity of the stationary wave.In SH,the lack of sensitivity to the location of heating can be associated with weaker activity of the stationary wave therein.展开更多
文摘Wheat (Triticum aestivum L.) is grown throughout the winter time in Southern Brazil and turns out to be the main agricultural crop at such a year season in the State of Paraná. However, throughout the crop growing season foliar diseases significantly compromise commercial yields in such a manner as to justify the application of fungicides at the right time to control foliar diseases in production fields. The aim of the current manuscript was to assess the impact of different timings for fungicide application (epoxiconazole + pyraclostrobin) on the control of leaf rust (Puccinia triticina E.) and yellow spot (Pyrenophora tritici-repentis) diseases in two wheat genotypes featured by distinct levels of susceptibility in Southern Brazil. A field trial was conducted in Ponta Grossa, State of Paraná, Brazil, in light of split plot statistical design at an experimental area belonging to CESCAGE. The following treatments were imposed in the current study: control (with no sprays);sprays at the first node, booting and heading;sprays at stem extension and flowering;sprays at booting and heading. Throughout the entire crop growing season, the control treatment was conducive to the highest severity levels for both diseases. The increasing of the area under the diseases progress curve assessed herein substantially impinged upon yield components of both wheat genotypes under scrutiny. In general, fungicide sprays at the first node did not culminate in economical advantages. The best timing for fungicide application was the one ascribed to booting and heading stages.
基金supported by the National Natural Science Foundation of China(41205048)the National Basic Research Program of China,"Structures,Variability and Climatic Impacts of Ocean Circulation and Warm Pool in the Tropical Pacific Ocean"(2012CB417403)the Special Project of Chinese Academy of Sciences(XDA11010401)
文摘A comparison of sensitivity in extratropical circulation in the Northern Hemisphere （NH） and Southern Hemisphere （SH） is conducted through observational analyses and diagnostic linear model experiments for two types of El Ni（n）o events,the traditional El Ni（n）o with the strongest warmth in the eastern tropical Pacific （EP El Ni（n）o） and the El Ni（n）o Modoki with the strongest warmth in the central tropical Pacific （CP El Ni（n）o）.It is shown that CP El Ni（n）o favors the occurrence of a negative-phase Northern Annular Mode （NAM）,while EP El Ni（n）o favors that of the Pacific-North American （PNA） pattern.In SH,both EP and CP El Ni（n）o induce a negative phase Southern Annular Mode （SAM）.However,the former has a greater amplitude,which is consistent with the stronger sea surface temperature （SST） warmth.The difference in the two types of El Ni（n）o events in NH may originate from the dependence of heating-induced extratropical response on the location of initial heating,which may be associated with activity of the stationary wave.In SH,the lack of sensitivity to the location of heating can be associated with weaker activity of the stationary wave therein.
