Plant path lab 2

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Plant path lab 2
2015-09-24 10:24:12
Plant path lab

Plant path lab 2
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  1. What are most seedling diseases considered?
    Facultative parasites
  2. What three ways do seedling diseases reduce crop stands?
    • -seed rot: seeds are infected before germination resulting in rotting of the seed
    • -pre-emergence dampening off: seedlings are infected and killed before emerging from the soil
    • -post-emergence dampening off: seedlings are infected and killed soon after emerging from the soil
  3. What are the most important genera that cause seedling diseases?
    • They are from the genera pythium and phytophthora
    • - they are considered stramenophiles because they produce zoospores in soil
    • - they also produce thick walled oospores (from meiosis) that serve as the primary survival structure in soil and plant debris
  4. Environmental conditions for seedling diseases
    • -heavy souls
    • -high soil moisture and low temps
    • -basically any environmental condition that is not optimal for growth or stresses the will predispose it to infection
  5. How to control pathogens causing seedling diseases
    • -apply fungicides or biological control agents to seed
    • -heat treat or fumigate greenhouse soil or transplant beds
    • -seeding or transplanting when conditions favor rapid emergence and growth of the crop
    • -breed disease resistant cultivars