physiological disorders Flashcards
what is a physiological disorder?
caused by the environment, not a pest or disease
name some physiological disorders
etoliated growth swollen, woody stems Raised leaf spots white blooms on leaves yellow leaf veins slime/oozing of stems dry/crumbling leaves
what is the cause of etoliated/elongated stems?
too little light.
move the plant to a more appropriate area
remove overhanging foliage
what is the cause (disease) for the symptom “swollen woody stems?” and what is the remedy?
bacterial canker
cut out infected material
apply pruning paint
don’t cut at junctions
what would cause raised leaf spots?
Rusts eg: Hollyhock rust
what do you have if there is a white bloom on the upper leaf surface?
a powdery mildew
what do you have if there is a white bloom on the lower leaf surface?
a downy mildew
why would you get yellowing leaf veins?
chlorosis
low iron and magnesium
-look at the soil pH. If it’s too high the nutrients are locked away from plant.
lower pH by adding FYM, pine needles as acidic.
what disease would you have if there is slime and oozing on stems?
Fire blight
if you have dry/crumbling leaves, what was the cause?
too much fertiliser or the plants have overheated.
what is reversion?
when a variegated plant goes back to it’s original green leaf.
name some variegated plants
Hedera-ivy
Ilex-holly
what is a preventative method for reversion?
prune out all new shoots and leaves.
