First Record of a Phytoplasma Associated with Faba Bean (Vicia faba L.) Witches’-broom in Egypt

Symptoms of growth abnormalities and shoot proliferation followed by decline, whereas at the flowering stage virescence, phyllody and witches' broom prevailed naturally affecting faba bean plants were observed in fields of two governorate, Egypt. These plants were examined for phytoplasma infections. Light microscopy of hand-cut sections treated with Dienes' stain showed blue areas in the phloem region of phyllody-infected plants. Electron microscopy of ultrathin section of infected plants revealed phytoplasma units inside phloem tissues. Dodder was transmitted into healthy faba bean and periwinkle plants. DNA of the Phytoplasma was detected in symptomatic faba bean samples through the specific amplification of their 16S-23S rRNA gene using nested PCR. Universal phytoplasma-specific as well as witches' broom-specific PCR primers have been used. This is the first report of a phytoplasma infecting faba bean in Egypt.