The protective effects of Xcn1 (12 and 6.0
l
g/L) and
Metalaxy WP (25%) against potato blight in potted plants
were compared. Xcn1 solution was sprayed on the leaves
of whole plants; after 30 min, treated and control plants
were inoculated with zoospore suspension (1
9
10
5
zoo-
spore/mL). Twelve potato plants were used for each
treatment and the test was repeated for three times. Inoc-
ulated plants were kept in a high-humidity chamber for
24 h in darkness and then transferred to normal photope-
riod and temperature (i.e., 16 h at 20–22
°
C). The area
covered with late blight lesions in each plant leaf was
estimated visually 9 days after inoculation. The protective
efficacy was calculated according to: 100
9
(1
-
lesion
area of total leaf area on treated plants/Lesion area of total
leaf area on control plants).