In all cropping seasons, incidence of rice blast was evaluated in
leaves and shoot-panicle. The effects on leaves were assessed
every 10 days in 10 plants selected at random from each plot; in
each plant, the first leaf (flag leaf) and the three leaves belowwere
examined.Disease severity was calculated according to Marı´nand
Almacellas (2002) and Galimany et al. (2006). In short, the leaf
surface affected by necrotic spots is associated to a given value and
that allows calculation of the leaf surface affected. The effects on
shoot-panicle were calculated in the same way on an adapted
scale. With data obtained along time, the area under the disease
progress curve (AUDPC) was calculated (Jeger and Viljanen-
Rollinson, 2001). To find differences between treatments, AUDPC
data were compared by unidirectional variance analysis
(ANOVA); when significant differences were found, least significant
difference (LSD) test was performed (Sokal and Rohlf,
1979).