- 1The fungus causing apple canker is described and its identity with Nectria galligena Bres. is confirmed.
- 2The methods of dispersal of the spores of Ngalligena have been examined. The ascospores are discharged forcibly from the perithecium, the eight spores of each ascus typically being ejected simultaneously.
- 3Field investigations have shown that spores are discharged during wet periods at all times of the year. Ascospore discharge reaches its maximum in January-February and falls to a minimum in the summer months.
- 4The dispersal of conidia occurs during wet periods in the spring and autumn.
- 5Germination both of ascospores and conidia occurs over a range of temperature from 2 to 30°C, the optimum being at 20°C.