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Agriculture for Secondary Schools
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Figure 8.7: Symptoms of Fusarium wilt in pigeon pea
Leaf spot: This is a disease caused by either fungus (fungal leaf spot) or bacteria
(bacterial leaf spot). The disease is characterised by spot that appears as small
brown or dark circles on leaves (Figure 8.8). It is common during wet and humid
conditions. When the disease is not controlled, leaves fall early and reduce the
plant’s strength. The disease spreads through old plant remains and splashing
rain. Management of the disease includes removing infected leaves and crop
remains. Proper plant spacing and clean seed also help to reduce the disease.
Figure 8.8 shows symptoms of leaf spot on pigeon pea.
Figure 8.8: Symptoms of leaf spot on pigeon pea
Powdery mildew: This is a disease that is caused by a fungal pathogen. It shows
up as a white or grey powder on leaves and stems (Figure 8.9). It is more common
during cool and dry weather. It weakens the plant and may reduce flowering
and pod formation. The disease can be managed by spraying with recommended
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AGRICULTURE F3.indd 133
AGRICULTURE F3.indd 133 17/09/2025 14:12
