Fig. 3From: Identification of two novel powdery mildew resistance loci, Ren6 and Ren7, from the wild Chinese grape species Vitis piasezkii Comparative development of powdery mildew on in vitro leaves of genotypes containing different combinations of R loci introgressed from Vitis piasezkii. Detached leaves were inoculated with powdery mildew using a settling tower, harvested 5 dpi and stained with Coomassie Brilliant blue to visualize the development of fungal structures on the leaf surface. (a) Ren6 −/Ren7 −, (b) Ren6 −/Ren7 +, (c) Ren6 +/Ren7 −, and (d) Ren6 +/Ren7 + genotypes. The brown cells beneath the appressoria of germinated fungal spores are the result of a hypersensitive response induced by the R loci. Scale bars represent 50 μmBack to article page