Phytopathology (2001) 91, 165-172

Ki Woo Kim, Eun Woo Park, Young Ho Kim, Kyung-Ku Ahn, Pan Gi Kim and Kyung Soo Kim (2001)
Latency- and defense-related ultrastructural characteristics of apple fruit tissues infected with Botryosphaeria dothidea
Phytopathology 91 (2), 165-172
Abstract: Apple fruit tissues infected with Botryosphaeria dothidea were examined by transmission electron microscopy using susceptible cv. Fuji and resistant cv. Jonathan. Immature (green) and mature (red) fruits of cv. Fuji with restricted or expanding lesions were also examined to reveal subcellular characteristics related with latent and restricted disease development. In infected susceptible mature fruits, cytoplasmic degeneration and organelle disruption commonly occurred, accompanying cell wall dissolution around invading hyphae. Cell wall dissolution around invading hyphae in subepidermis was rare in immature, red halo-symptomed cv. Fuji and resistant cv. Jonathan fruits. In infected immature fruits of cv. Fuji, presumably at the latent state of disease development, cellular degeneration was less severe, and invading hyphae contained prominent microbody-lipid globule complexes or the deposition of thin electron-dense outer layer around cell wall of intercellular hyphae. Both mature fruits with red halos and resistant apple fruits formed cell wall protuberances at the outside of cell walls. In addition, electron-dense extramural layers were formed in the resistant apple fruits. Aberrant hyphal structures such as intrahyphal hyphae were found only in resistant fruit tissues, indicating the physiologically altered fungal growth. These ultrastructural changes of host tissues and fungal hyphae may reflect the pathogenesis of apple white rot under varying conditions of apple fruits.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Full text of article
Database assignments for author(s): Young Ho Kim, Eun Woo Park

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution
resistance/tolerance/defence of host

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Botryosphaeria dothidea	Apple (Malus)