Regional-based typology of the main fungal diseases affecting winter wheat in the Grand-Duchy of Luxembourg

Despite its small territory size, the Grand-Duchy of Luxembourg (GDL) has
several microclimates that result in a variability of disease severity between
the South (Gutland) and the North (Oesling). Septoria leaf blotch disease of
wheat is an important disease in the GDL. Over 2003–2009, the severity was
strong in Gutland (51% on average over the last two upper leaves at the late
milk growth stage) and low in the Oesling (16% for the same leaves). For the
years 2006, 2008 and 2009, the disease severity was less than 6% in the
Oesling while it exceeded 40% in the Gutland. The second fungal disease that
has become economically important is the wheat leaf rust. Over the same
period, the Gutland and the Oesling showed consistently the highest and
lowest disease severity respectively. In 2003 and 2007, the Gutland showed
the highest disease severity with 66% and 57% respectively, whereas the
lowest severity (<1%) was observed in the Oesling. Another important disease is wheat powdery mildew. The 2003 and 2009 cropping seasons showed the
highest disease severity with 15% and 40%, respectively, in the Oesling
whereas less than 1% severity was registered in the Gutland. Fusarium head
blight was also present in the eastern part of the Gutland showing the highest
prevalence and severity in 2007 and 2008 (8.5% and 8.3% respectively).
These prevalence and severity percentages were significantly higher compared
to the Oesling (% prevalence % severity, p = 0.049 and p = 0.012,
respectively, Tukey’s test).