Histopathology of infection and development of Botrytis allii in onion floral and seed stalk tissues [Egypt]

• Published in: Egyptian Journal of Phytopathology (Egypt) Vol. 20; no. 1
• Main Authors: Abd-El-Razik, A.A. (Assiut Univ. (Egypt). Faculty of Agriculture), El-Shabrawy, A.M, Rushdi, M.H, El-Ganieny, R.M
• Format: Publication
• Language: English
• Published: 1988
• Subjects: ALLIUM CEPA; BOTRYTIS; CUTICULA; CUTICULE; EGIPTO; EGYPTE; FLORA; FLORE; HISTOLOGIA; HISTOLOGIE

Infection processes of Botrytis allii, the causal of blasting disease of onion seed heads, were studied on inflorescences of susceptible Giza 6 onion cultivar. Conidia of the fungus germinated on the upper surface of flower petals after one day from inoculation. Penetration of the host by the fungus took place directly by germ tubes through the cuticle. After penetration, the invading hyphae grew and spread into epidermis, cortex and vascular elements of petals causing complete disintegration of parenchymatous cells. The hyphae were not observed in other flower parts. Six days later infection of flower pedicles occurred either by hyphae spreading from infected petal tissues to pedicle tissues or by direct penetration of hyhae growing on the pedicle surface. Death and disintegration of invaded parenchymatous tissues of the pedicles were observed.