The mind mapping of plant disease (clubroot of crucifer, late blight of potato and downy mildew of grape).

1. • Avoid growing cruciferous
crops in fields that have been
infested with the clubroot
pathogen
• Well-drained fields, pH slightly
above neutral (pH 7.2) or in
fields, hydrated lime has been
added to raise the soil pH
• Treat the soil with chloropicrin,
methyl bromide or metam
sodium approximately 2 weeks
before planting
• Infected plants from pale
green to yellowish leaves
• Dicolouring
• Wilting in the middle of
sunny days
• Young infected plant may
be killed
• The older infected plant
remains alive but stunded
Clubroot of
crucifer
casual pathogen
disease sign or
symptom
disease cycle
disease
management
Plasmodiaphora brassicae sp.

2. Potato tubers
• Affected tubers at first
show purplish or
brownish
• blotches consisting of
water-soaked, dark,
reddish brown tissue
that extends into the
flesh of the tuber
• Later, become firm,
dry and sunken
• The rot continues to
develop after the
tubers are harvested
Late blight of
potato
casual
pathogen
disease sign of
symptom
disease
manangement
disease cycle
Phytophothora sp.
• Sanitary measures
• Resistant varieties
• Chemical sprays

3. Downy
mildew of
grape
disease cycle
disease sign of
symptom casual pathogen
disease manangement
Plasmopara viticola and
P. halstedii
• Small, pale yellow,
irregular spots appear
on the upper surface of
the leaves,
• a downy growth of the
sporophores of the
fungus appears on the
underside of the spots
• The infected leaf areas
are killed and turn
brown, sporophores of
the fungus become
dark gray
Fungicides – Bordeaux mixture,
mancozeb and captan before bloom
and continued at 7-10-day
intervals,
or depend on frequency of rainfall
during growing season