Figure 4.

Microscopic observations on powdery mildew infection and development of the infection units (IU) of Oidium neolycopersici on six different genotypes. In each panel photos are taken from (A) and (B) F₄ plants carrying the m200 allele, (C) a plant carrying the RNAi::SlMLO1 construct, (D) and (E) plants carrying the ol-2 allele in Moneymaker (MM) and Super Marmande (SM), (F) MM, respectively. Photos of two IU/genotype are shown, except for the MM and F₄-2 carrying the m200 allele where only one IU is shown. Each photo is taken with different focus to observe all the fungal structures and papillae, from the most superficial to the deepest ones. Sp = spore, AP = appressorium; HS = haustorium; 2 hyphae = secondary hyphae.