ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

The biology and pathology of the fungus Rhizopus stolonifer, cause of black mould disease of table grapes in Israel.

Lisker, N., Keren-Shacham, Z., Sarig, P., Zutkhi, Y. and Ben-Arie, R.

Plant Pathology Year: 1996 Vol: 45 Issue: 6 Pages: 1099-1109 Ref: 19 ref.

1996

บทคัดย่อ

R. stolonifer was isolated from soils throughout the year, and from fruits after mid-Jun. in Israel. The airborne spore population increased in vineyards at fruit maturation and was related to the proximity of stone-fruit orchards. Population size was highly correlated with disease incidence and it is suggested that it could be used for disease prediction. Intact young berries were more resistant to Rhizopus inoculation in the vineyard and in the lab. than mature berries. Mechanical wounding or chloroform dips greatly increased the susceptibility of young berries. Acidity decreased and soluble solid content and susceptibility to inoculation increased during growth and maturation of the berries. SEM revealed that the fruit surface was covered with white amorphous structures. At high magnification cracks (c. 1 micro m length) were observed, but no fungal penetration through them was observed. In artificially inoculated fruits the fungus germinated near the wound and developed vigorously inside and

 around the fissure, producing sporangia. The young sporangia were covered by a smooth external layer compressed against the sporangiospores. After lysis of the cover the hexagonal sporangiospores were observed. At maturation the columella collapsed and the sporangiospores were dispersed. In naturally infected berries the incomplete connection between the berry and the pedicle was important for fungal penetration. Heavily infected berries become disconnected from their pedicles. Orthophenylphenate (as a fog) and calcium hypochlorite (as chlorine vapour), significantly decreased postharvest decay in artificially inoculated berries.