Efficacy of Xcn1 against
P. infestans
in detached potato
leaves
The efficacy of Xcn1 against potato late blight was asses-
sed using the floating leaf-disk method. Xcn1 was diluted
in water to 12, 6, 3, and 1.5
l
g/L. Potato leaf disks (14 mm
diameter) were placed in 0.5% sodium hypochlorite solu-
tion for 1 min, washed with sterile distilled water three
times, and then floated on different concentrations of Xcn1
solution, with distilled water without Xcn1 used as control.
After floating for 2 h, each disk was inoculated with 20
l
L
suspension of 4
9
10
4
mL sporangia. The closed plates
were incubated at 18
±
1
°
C with 16 h light per day. After
5–7 days of incubation, the area of the leaf disk occupied
with fungal mycelia and sporangia was recorded and
inhibition of late blight was calculated in comparison with
the control treatment. Five leaf disks were used for each