Over the 2003-2009 period, field campaigns were carried out in order to identify the main fungal diseases of winter wheat （Triticum aestivum） in the Grand-Duchy of Luxembourg. Four fungal diseases （septoria leaf bl...Over the 2003-2009 period, field campaigns were carried out in order to identify the main fungal diseases of winter wheat （Triticum aestivum） in the Grand-Duchy of Luxembourg. Four fungal diseases （septoria leaf blotch （SLB）, wheat leaf rust （WLR）, wheat powdery mildew （WPM） and fusarium head blight （FHB）） were observed and a regional-based typology was established according to their severity and prevalence. In the Gutland （South）, SLB severity was strong （about 51% on average） and higher than the severity （about 16%） prevailing in the Oesling （North）. Similar typology was observed with the WLR： high severity in the Gutland （66% and 57% for the years 2003 and 2007, respectively） and low severity （〈 1%） in the Oesling. The FHB was also present in the Eastern part of the Gutland, with a prevalence and severity significantly higher （P = 0.049 and P = 0.012, respectively, Tukey＇s test） compared with their values in the Oesling. On the other hand, the WPM severity was high in the Oesling （15% to 40%） while less than 1% in the Gutland. Such a study is important for the spatial mapping of wheat fungal diseases risk based on agroclimatic parameters and for defining optimal frequencies and dates of chemical treatments.展开更多
We study the asymptotic behavior of an incompressible viscous fluid flow in a biological body lined by a thin biological film with a cellular microstructure,varying thickness,and a heterogeneous viscosity regulated by...We study the asymptotic behavior of an incompressible viscous fluid flow in a biological body lined by a thin biological film with a cellular microstructure,varying thickness,and a heterogeneous viscosity regulated by a time random process.Let ting the thickness of the film tend to zero,we derive an effective biological slip boundary condition on the boundary of the body.This law relates the tangential fluxes to the tangential velocities via a proportional coefficient corresponding to the energy of some local problem.This law describes the ability of the biological film to function as a lubricant reducing friction at the wall of the body.The tangential velocities are functions of the random trajectories of a finely concentrated biological particle.展开更多
文摘Over the 2003-2009 period, field campaigns were carried out in order to identify the main fungal diseases of winter wheat （Triticum aestivum） in the Grand-Duchy of Luxembourg. Four fungal diseases （septoria leaf blotch （SLB）, wheat leaf rust （WLR）, wheat powdery mildew （WPM） and fusarium head blight （FHB）） were observed and a regional-based typology was established according to their severity and prevalence. In the Gutland （South）, SLB severity was strong （about 51% on average） and higher than the severity （about 16%） prevailing in the Oesling （North）. Similar typology was observed with the WLR： high severity in the Gutland （66% and 57% for the years 2003 and 2007, respectively） and low severity （〈 1%） in the Oesling. The FHB was also present in the Eastern part of the Gutland, with a prevalence and severity significantly higher （P = 0.049 and P = 0.012, respectively, Tukey＇s test） compared with their values in the Oesling. On the other hand, the WPM severity was high in the Oesling （15% to 40%） while less than 1% in the Gutland. Such a study is important for the spatial mapping of wheat fungal diseases risk based on agroclimatic parameters and for defining optimal frequencies and dates of chemical treatments.
文摘We study the asymptotic behavior of an incompressible viscous fluid flow in a biological body lined by a thin biological film with a cellular microstructure,varying thickness,and a heterogeneous viscosity regulated by a time random process.Let ting the thickness of the film tend to zero,we derive an effective biological slip boundary condition on the boundary of the body.This law relates the tangential fluxes to the tangential velocities via a proportional coefficient corresponding to the energy of some local problem.This law describes the ability of the biological film to function as a lubricant reducing friction at the wall of the body.The tangential velocities are functions of the random trajectories of a finely concentrated biological particle.
