Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
45 Cards in this Set
- Front
- Back
|
Plant Disease
|
-Series of physiological processes
-Caused by irritation of plant by primary agent -Leads to abnormal cellular activity expressed as symptoms |
|
|
Stages of Attack
|
-Incoulation
-Incubation -Infection |
|
|
Inoculation
|
Transfer of inculam from source to infection court
|
|
|
Incubation
|
Inculum starting to grow but no symtoms
|
|
|
Infection
|
-inculum irritates plant
|
|
|
Local disease
|
Disease that stays in only one portion of plant
|
|
|
Systemic disease
|
Disease spreads throughout plant
|
|
|
Types of causal agents
|
Fungi
Bacteria Virus |
|
|
Fungi
|
Largest common group of causal agent
|
|
|
Feeding habits of fungi
|
Saprophytes: eat dead material
Parasitic: eat living material |
|
|
Hyphae
|
Strands of fungi
|
|
|
Mycelium
|
Mass of hyphae
|
|
|
Types of Fungi
|
Myxomycetes
Phyxomycetes Ascomycetes Basidiomycetes Deuteromycetes |
|
|
Myxomycetes
|
-NO spores
-Holocarpic Reproduction |
|
|
Phyxomycetes
|
Spores produced in sporangium
|
|
|
Ascomycetes
|
Spores produced in Ascus
|
|
|
Basidiomycetes
|
Spores produced in Basidia
|
|
|
Deuteromycetes
|
-aka "Fungi Imperfecti"
|
|
|
Bacteria
|
-smaller than fungi
-are parasitic -use flagella to move -Enter through stoma or wound |
|
|
Mycoplasmas
|
-smaller than bacteria
|
|
|
Virus
|
-obligate parasite that invades and multiplies
|
|
|
Symptomatic Groups
|
Neucrotic Symptoms: Death of cells, tissues, organs
Chlorotic: patterned yellowing Hypoplastic: stunted growth Hyperplastic: fast growth |
|
|
Stem and Root Rot
|
Agent: Phyxomycetes
Symptoms: Herbaceous plant roots rot. Woody plant tissue turns brown. Fast with herbaceus, slow with woody -Conditions: poor drainage |
|
|
Lear Curl
|
Agent: Ascomycetes
Symptoms: Puckered, discolored leaves. Bumpy fruit Conditions: Warm, moist springs |
|
|
Powdery Mildew
|
Agent: Ascomyctes
Symptoms: white mycelial patches. Leaf browns, falls Conditions: Reduced light, cool nigts & warm days |
|
|
Scab
|
Agent: Ascomycetes
Symptom: Affect fruit and leaves. Velvety green spots, nucretic areas with brown margins, raised corky areas Conditions: warm, humid, rains |
|
|
Anthracnose
|
Agent: Acomycetes
Symptoms: lesions along veins and margins Conditions: wet, moist springs |
|
|
Canker
|
Agent: All exept phxo and myxomycetes
Symptoms: nucretic lesions on stem Conditions: mechanical abrasions, improper pruning |
|
|
Dutch Elm
|
Causal Agent: Ascomycetes
Symptoms: Leaves on branches wilt and yellow suddenly. Brown streaks across xylem. Conditions: Elm bark beetle spreads. |
|
|
Rust
|
Agent: Basidiomycetes
Symptoms: Red pustules Conditions: Water necessary for spore germination. |
|
|
Verticilium Wilt
|
Agent: Fungi Imperfecti
Symptoms: Herbaceous plants wilt and brown from bottom up. Woody sudden leaf wilting and death. Works fast Conditions: 75F and below favor |
|
|
Fusarium Wilt
|
Agent: Fungi Imperfecti
Symptoms: Slow acting. Shoots wilt, stunting, brown/black base Conditions: 80F above favor |
|
|
Leaf Spots
|
Agent: Fungi Imperfecti
Symptoms: Nucreotic leaf areas with straw center and dark margins Conditions: wet weather, overhead irrigation |
|
|
Crown Gall
|
Agent: Agrobacterium tumefaciens
Symptoms: galls Conditions: warm months, wounds |
|
|
Fireblight
|
Agent: Bacteria
Symptoms: shoots/leaves wilt, darken, die, remain. Conditions: rodents, insects, rain spreads |
|
|
Leaf Spot
|
Agent: Bacteria
Symptom: Lesions crack and merge Conditions: rain |
|
|
Soft Rot
|
Agent: Bacteria
Symptom: Bad small, wilting and death of plant Conditions: Warm conditions |
|
|
Aster Yellows
|
Agent: Mycoplasmas
Symptom: Yellowing on new tissue, rosetting Condition: Leaf Hopper |
|
|
Mosaic
|
Agent: Virus
Symptom: Irregular brilliant yellow patches. Flower color breaks Condition: Piercing-sucking insects, Mechanically |
|
|
Nutrient Deficiencies
|
SYMPTOMS:
-N: leaf yellowing -P: Vein Purpling, Delayed fruiting/flowering -K: nucrosis/curling -Fe: Intervenal chlorosis Conditions: Sandy soils, excessive cropping |
|
|
Nutrient Excess
|
Symptoms: Cease of fruiting/flowering. Reverse osmosis
Conditions: Improper irrigation |
|
|
Incorrect PH
|
Symptoms:
-Low PH: stunted growth -High PH: leaf burn and chlorosis Conditions: Low PH:Uneven irrigation High PH: Poor drainage |
|
|
Water Imbalance
|
Symptoms:
-Drought: Wiliting, yellowing, scorching -Excess: Stunting, yellowing, leaf drop Conditions: Poor Watering Practices |
|
|
Temp Imbalance
|
Low: stunting, nucrosis
High: marginal nucrosis, scorching Conditions: Seasonal extremes |
|
|
Light Absence
|
Symptoms: stunted growth, chlorophyll retardation
Condition: northern exposure with sun lovers. |
