Friesia X, 4-5

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Fig . 4. Leptosphaeria nodorum. Pycnospores on barley. X 540.
after harvest. Perithecia are immersed, globose with a short papillate
ostiole, dark brown to black, 100-240 f-l in diameter. Asci cla vate,
cylindrical or slightly curved, eight-spored, 51-80 X 9-12 f-l; wall is
bitunicate. Ascospor es are biseriately arranged, straight or slightly
curved, three-septate, constricted at the septa and typically with the
second cell from the apex somewhat enlarged (Fig. 5). The spores are
hyaline, often with guttules, 19-28 X 4.4-5.6 f-l (average 23.8 X 5.0 f-l,
100 measurements in water).
Fig. 5. L eptosphaeria nodorum. Asci and ascospores on barley. X 625.
The size of pycnidia, pycnospores, asci and ascospores were compared
with measurements reported by other workers for Leptosphaerui
nodorum from barley and wheat (Table 1) . Data are also