QUANTITATIVE EVALUATION OF TWO TECHNIQUES FOR THE DETECTION OF EPIPHYTIC ERWINIA AMYLOVORA DURING THE DORMANT PERIOD
Two sampling detection techniques have been studied to reveal epiphytic germs of E. amylovora during the dormant period. The samples consisted of groups of buds and their leaf scars or bundles of 50 cm long pieces of one-year shoots, and quantitatively contaminated by germs of E. amylovora. Buds and leaf scars were ground and suspended in a buffer. Bunches of shoots were washed in a buffer in a rotary shaker. A final pellet was obtained by centrifuging thick suspensions or washing fluids to concentrate the germs and used to inoculate pear fruitlets. E. amylovora was isolated from the experimental lesions.
The sensitivity thresholds for a successfull indirect isolation were evaluated to be 7.25×103 germs contaminating 100 buds and leaf scars, and 6.69×103 germs contaminating a bunch of 15–20 one-year shoots.
Mazzucchi, U., Bazzi, C., Coti, G., Gasperini, C. and Calzolari, A. (1984). QUANTITATIVE EVALUATION OF TWO TECHNIQUES FOR THE DETECTION OF EPIPHYTIC ERWINIA AMYLOVORA DURING THE DORMANT PERIOD. Acta Hortic. 151, 145-154