Biological Properties of Container Media

Question 1

Liverwort, moss, and algae

Answer 1

problems: poor irrigation, grows on surface when media is wet, limits oxygen/gas exchange, hydrophobic, fungus gnat habitat
control with topdressing with sawdust

Question 2

cultural weed control methods

Answer 2

sanitation
irrigation
monitering for weeds

Question 3

mechanical/physical weed control methods

Answer 3

hand removal
removal from greenhouse floors and perimeter
hoeing
topdressing, crop covers

Question 4

chemical weed control methods

Answer 4

less laborious to apply
takes time to prepare
i.e. acetic acid (vinegar), glysophate

Question 5

common pests found on surface/underside of containers

Answer 5

slugs
mealybugs
centipedes
millipedes
cutworms

Question 6

fungus gnats symptoms

Answer 6

poor growth quality
stunted plants

Question 7

fungus gnats signs

Answer 7

adult flies present (sticky cards for moniter)
small flies hover when disturbed

Question 8

fungus gnats lifecycle

Answer 8

complete metamorphosis
egg to egg laying adult (28-35 days)
larva feed on roots

Question 9

fungus gnat control

Answer 9

chemical: allow surface to dry/topdress
biological: beneficial nematodes

Question 10

mealy bug symptoms

Answer 10

poor growth quality
yellowing of leaves
honey dew

Question 11

mealy bug signs

Answer 11

adults present
nymphs hard to see
cottony wax exudate

Question 12

mealy bug life cycle

Answer 12

incomplete metamorphosis (28-35days to maturity)
adults live 2-5 weeks
feed on plants at all stages

Question 13

mealy bug control

Answer 13

cultural: avoid heavy nitrogen
physical: water washing/repotting
chemical: insecticidal soaps
biological: cryptolaemus montrouzieri

Question 14

fusarium wilt symptoms/signs/conditions

Answer 14

symptoms: brown necrosis/wilting
signs: stringy stems, mycelium stems, sporangium
optimal conditions: dry soil, high salts

Question 15

phytophthera symptoms/conditions/control

Answer 15

symptoms: wilt, new growth dieback, brown roots
optimal conditions: wet media, warmer
control: chemical (irrigation management)

Question 16

pythium symptoms/conditions/control

Answer 16

symptoms: stunted, wilt, brown root tips, death, damp off, black leg
optimal conditions: long warm temp, cool/wet, moisture, lack of sanitation
control: physical (remove affected plants), cultural (allow media to dry, dont exceed 28 degrees)

Question 17

rhizoctonia symptoms/conditions/control

Answer 17

symptoms: wilting/damping off, seed fails to germinate, red/brown lesions, canker
optimal conditions: damp media/warm conditions
control: cultural (porous media/sanitation), physical (remove affected plants), chemical (fungicides, hydrogen peroxide)

Question 18

verticillium wilt symptoms/conditions/control

Answer 18

symptoms: wilting, necrosis, chlorosis, discoloured vascular tissue, canker
optimal conditions: root damage, high salt, moist media
control: chemical (sanitation, avoid transmission, aeration, resistant varieties)

Question 19

thielaviopsis symptoms/conditions/control

Answer 19

symptoms: stunting, chlorosis, blackened roots
optimal conditions: 12-18C, moisture
control: chemical (warm soil, dont keep wet)

Question 20

advantages for biological control agents

Answer 20

reduced pesticide use
health
plant damage
no REI
less equipment

Question 21

challenges of biological control agents

Answer 21

knowledge required
complexity
does not work well in combo with chemicals

Question 22

types of biological control agents

Answer 22

predators
parasites
biofungicides
banker plants
agricultural biostimulants

Question 23

types of parasites

Answer 23

parasitic wasps
chalcid and braconid wasps
parasitic nematodes

Question 24

banker plants

Answer 24

used to farm predatory insects for i.e. cereal plants and ornamental peppers

Question 25

agricultural biostimulants

Answer 25

improves nutrient uptake
increase plant stree tolerance
bacterial and microbial inoculants (amino, humic, fulvic, seaweed acids)