STATISTIC ASSIGNMENT OF FUSARIUM OXYSPORUM FSP MELONIS STRAINS TO RACES 0 1 2 AND 12
L. Languasco, S. Giosué, V. Rossi, G. Mecenero
Cultivars and differential genotypes of muskmelon were artificially inoculated with isolates belonging to the physiological races 0, 1, 2, 1-2y and 1-2w of Fusarium oxysporum f.sp. melonis and 31 isolates of the same forma specialis from northern Italy. The results showed that: cultivars ‘Aril’, ‘Delada’ and ‘Supermarket’ can be used in pathogenicity tests instead of the differential genotypes because they have the same reaction to infection; the best separation of fungal isolates into the five races was achieved thirty days after inoculation, when almost all the plants of the susceptible cultivar had been affected; multivariate statistical analyses (i.e. cluster and discriminant analyses) assign isolates more reliably to the right race than the empirical criteria commonly used.