PSS 10: Diseases
Terms
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- What is the definition of disease in plants?
- -any kind of inuriuos abnormality
- What are the two categories of disease in plants?
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-physiological (environment)
-other living organisms (pathogens) - What is a pathogen?
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-biological agent that causes the injury
-insecets, bacteria, fungi, viruses, nematodes, etc. - What is the defintion of parasite?
- -an organism that derives nourishment from another living organism
- What is a host?
- -an organism that provides nourishment to another
- What is an obligate host?
- -organism that can only survive on the living host
- What is a host range?
- -list of several different plants that some parasites can feed off of
- What is the definition of bacteria used in this course?
- -one celled organism that enters through wounds and causes rot
- What is the definition of fungi in this class?
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-multi celled organisms that are either sprophytes or parasites such as molds and mildews
-causes decay of plants - How do you perform bacterial disease control?
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-start with clean pots, media, and tools
-start with clean seed or healthy transplants
-use drip irrigation or water in morning to evaporate by evening - How do antibiotics work for trees?
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-must be injected
-very costly
-only temporary effects
-no topical sprays yet that work - How do you perform fungal disease control?
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-start with clean pots, media, tools, seeds, or healthy transplants
-use drip irrigation or water in morning for evaporation by evening
-fungicides can be used as liquid drech, spray, or powder - What are two synthetic fingicides?
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-captan
-thiram - What is the definition of virus for this class?
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-infectious particles made up of nucleic acids with a protein coat
-obligate parasites
-no control methods - What are nematodes in this class?
- -unsegmented worms that feed on roots and create wounds for bacteria and fungi to enter
- How does actual damage occur to plants?
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-direct feeding
-secretion of toxic substances
-secondary organism enters wound - What is the most common symptom of plant damage/disease?
- -wilting
- What else can you look for in a plant that may be damaged/diseased?
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-organism
-evidence of organism (web, tunnels, wax, etc)