Sections of young leaves 0.5 cm from a rosebush with signs of powdery mildew were fixed in glutaraldehyde at 3 % for 24 h, and were later washed with Sorensen᾽s phosphate buffer 0.2 M. The samples were dehydrated by sinking them in ethanol at gradual concentrations 30, 40, 50, 60, 70, 80, 90 % for 40 min each, and at 100 % three times for 20 min.
Fragmentos de hojas jóvenes 0.5 cm de rosa con signos de cenicilla se fijaron en glutaraldehído al 3 % durante 24 h, posteriormente se lavaron con buffer de fosfato Sorensen᾽s 0.2 M. Las muestras se deshidrataron mediante la inmersión en etanol a concentraciones graduales 30, 40, 50, 60, 70, 80, 90 % por 40 min cada uno y al 100 % tres veces por 20 min.