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7 Cards in this Set
- Front
- Back
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What are the symptoms and signs of vascular wilts?
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Sudden wilt and death of plants
Premature yellowing of lower leaves Vascular discoloration Viscous ooze in vascular system (for bacterial wilts) |
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Which species commonly has f.sp.?
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Fusarium oxysporum (f. sp. niveum (watermelon)
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What causes Dutch elm disease?
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Ophiostoma ulmi vectored by European Elm bark beetle
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What causes Southern bacterial wilt?
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Ralstonia solanacearum
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How would you distinguish between the seedling blights caused by Rhizoctonia and Pythium?
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Rhizoctonia has thick mycelium with 90 degree angle, septa, and constriction with sclerotia. Pythium has mycelium that is coenocytic with zoospores/sporangia and oospores, oogonia and anteridia
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How would you distinguish between a disease caused by Rhizoctonia solani and Sclerotium rolfsii?
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Rhizoctonia has thick mycelium with clustered sclerotia. Sclerotium rolfii has ropey mycelium with single sclerotia.
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How would you distinguish between vascular wilt caused by Fusarium oxysporum f.sp. niveum and Ralstonia solanacearum?
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Fusarium oxysporum would have mycelium, macroconidia, microconidia, chlamydospores. Ralstonia would have oozing and streaming.
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