| AFFECTING WHOLE PLANT: |
|
CONDITION |
CAUSE |
 |
Seeds do
not germinate; a poor stand despite using fresh seed and maintaining
proper germination conditions |
Damping off Pythium,
Rhizoctonia, and other fungi)
|
 |
Young
plants stunted and yellow along with gradual wilting of older plants |
Fusarium wilt (Fusarium
oxysporum)
|
|
| AFFECTING LEAVES: |
|
CONDITION |
CAUSE |
 |
Yellow
area on leaf upper surface with blue-gray patches on undersides of
leaves |
Downy mildew (Peronospora
effusa)
|
 |
Young
center leaves turn yellow and curl, followed by mottling, browning, and
death of larger leaves |
Mosaic
|
 |
Yellow
deformed leaves that eventually die, along with stunted plants |
Curly-top
|
 |
Yellow
curled leaves and stunted growth |
Aphids, usually green peach
aphids
|
 |
Light-colored
winding tunnels in leaves; becomes an enlarged blotch at the ends of
leaves which may turn white or brown |
Spinach leaf miner
|
 |
Small
holes in leaves, undersides of leaves may be skeletonized |
Flea beetles (Phyllotreta
spp.)
|
 |
Ragged
holes in outer leaves, usually between leaf veins |
Cabbage looper and/or
Beet
armyworm
|