Different studies [5, 15, 16] have confirmed that, during spring and the beginning of summer, the severity of an epidemic for this pathogen is conditioned by the number of pycnidiospores produced in the crop; nevertheless, ascospores are present from the time that the first basal leaves are infected .
Ascospores were monitored only on Vaseline (AV), whereas pycnidiospores were monitored on Vaseline (PV) and rainwater (PRW).
Data on the number of pycnidiospores in rainwater (PRW) and in Vaseline (PV) and on the number of ascospores in Vaseline (AV) were recorded.
Four counts (considering all the area of the cover glass) of the number of pycnidiospores were done on each sample per week.
Only the pycnidiospores with three-seven septa (mostly three) and with a size of 30-80 x 1.5-2 [micro]m  were considered for counting.
For counts of airborne pycnidiospores and ascospores, the slide glass covered by PV was stained with three drops of an aniline blue (1/100) solution and then covered by a cover glass that enclosed all the area of 119 [mm.sup.2].