title: Physical Changes in Satsuma Mandarin Leaf after Infection of Elsinoë fawcettii Causing Citrus Scab Disease.
abstract: Citrus scab disease is one of the destructive diseases that reduce the value of fruit for the fresh market. We analyzed the process of symptom development after infection with scab pathogen Elsinoë fawcettii in the susceptible satsuma mandarin leaves to observe the structural modification against pathogen. The cuticle and epidermal cells along with 3-5 layers of mesophyll tissue were degraded 1-2 days post inoculation. Surrounding peripheral cells of degraded tissues grew rapidly and then enveloped the necrotic area along with the growing conidia. Cross sections through the lesion revealed hyphal colonization in epidermis and mesophyll tissues. In response to the pathogen colonization, host cell walls were lignified, inner cells were rapidly compartmentalized and a semi-circular boundary was formed that separated the infected region from the non-infected region, and finally prevented the intercellular pathogen spread.
authors.affiliation: Citrus Research Institute, National Institute of Horticultural and Herbal Science, Rural Development Administration, Jeju 63607, Korea.
authors.forename: Dilli Prasad
authors.initials: DP
authors.lastname: Paudyal
authors.affiliation: Citrus Research Institute, National Institute of Horticultural and Herbal Science, Rural Development Administration, Jeju 63607, Korea.
authors.forename: Jae-Wook
authors.initials: JW
authors.lastname: Hyun
keywords: citrus scab pathogen; infection process; structural defense; symptom development; time course infection