Fig. 9.

Lesion of Cercospora leaf spot (CLS) on the susceptible sugar beet genotype Bv6_s without and with conidia of Cercospora beticola. a Lesion 19 days post inoculation (dpi; left) and after incubation under 100% relative humidity for 2 days (centre and right; 21dpi). The incubation induced the formation of dark conidiophores protruding out of the leaf surface and bearing long, hyaline conidia. b Lesion with C. beticola conidia (top) and after removal of conidia by using a pencil (bottom). c Spectrum of lesion areas with and without conidia and spectrum of conidia taken by lateral focussing on the layer of conidia