PLANT PROTECTION 1 – Pests, Diseases and Weeds

PLANT PROTECTION 1 – Pests, Diseases and Weeds
SYMPTOMS
(contd)
ABOVE GROUND
NON-SPECIFIC. SYMPTOMS
Root knot nematodes.
Root lesion nematodes, etc.
Damage is largely the result of nematodes
feeding on or in roots. Symptoms are
similar to those of water stress, nutrient
deficiencies, etc. Plants may wilt on hot
days, show poor or stunted growth and
poor yields. For a positive diagnosis,
plants must be removed from soil and
roots examined.
Non-specific symptoms make diagnosis
difficult for the average horticulturist.
ABOVE GROUND
SPECIFIC. SYMPTOMS
Foliar nematodes.
Stem and bulb nematode.
Damage is largely the result of nematodes
feeding on or in aerial parts. Symptoms
have a distinctive appearance.
LEAVES.
Above
ground
symptoms
ROOTS.
Below
ground
symptoms
254 Nematode diseases