| AFFECTING ROOTS: |
|
CONDITION
|
CAUSE
|
 |
Yellow,
stunted plants that wilt during bright, hot days and recover at night |
Cabbage root maggots
|
|
| AFFECTING LEAVES: |
|
CONDITION
|
CAUSE
|
|
Yellow
v-shaped spots on leaf margins |
Black rot (Xanthomonas
campestris)
|
|
Yellowish
leaves, lower leaves drop; stunted plants may have twisted stems,
usually occurs soon after transplanting |
Fusarium yellows (Fusarium
oxysporum)
|
|
Yellow
leaves, older leaves first, slow growth |
Nitrogen deficiency
|
|
Yellow
leaves |
Cold weather
|
|
Yellow,
curled leaves; stunted plants |
Aphids
|
|
Brown
leaves that wilt and die |
Harlequin bug (Margantia
histrionica)
|
|
Tan to
dark-brown leaf margins |
Heat injury
|
|
Small
holes, shothole injury |
Flea beetles (Phyllotreta
spp.)
|
|
Large
holes in leaves; outer leaves riddled |
Cabbage worms (Pieris
rapae)
or Cabbage looper
|
