DR JEREMY BURGESS / SCIENCE PHOTO LIBRARY. DR JEREMY BURGESS / SCIENCE PHOTO LIBRARY.
Scanning electron micrograph of a pathogenic fungus Erisyphe pisi also known as E. polygoni, cause of powdery mildew on grasses including cereals, clover, & peas. The infection begins with a conidium germinating a short germ tube, which attaches to the surface with a pad or appressorium. A tube grows from under the pad into the epidermis. If the plant is susceptible the tube produces haustoria (food gatherering organs). A network of mycelium develops (seen here), hugging the leaf surface (pea). It sends up specialised hyphae, or conidiophores (upright stalks), which bear capsulelike conidia (spores) Mag:X500 (10x8 size).
Model release not required. Property release not required.