Crop Protection Flashcards
What is a monoculture
When Only one plant makes up the community
Weeds compete for…
Water
Light
Space
Nutrients
Weeds can:
Release chemicals to inhibit growth of crops
Contaminated grain crops
Act as hosts for crop priests and diseases
What are the two types of weed
Annual
And
Perennial
Annual weeds
They grow and disperse their seeds and die within one growing season
Perennial
They life for more than two years, remaining dormant in winter before growing again in spring
Three types of pests
Insects
Mollusc (slugs)
Nematode (worms)
Herbicides kill…
Weeds
Fungicides kill….
Fungus
Molluscicides kill
Mollusc pests
Nemotides kill
Nematode pests
Herbicides can be either:
Selective
Or
Systemic
Selective herbicides
This speeds up the metabolism of broad leaves weeds to the extent that they use their food reserves and di
Systemic herbicides
Absorbed by the eeeds and spread through the vascular system to all areas of the weed
Advantage of selective herbicides?
Greater effect of certain plant species (broad leaves weeds)
Advantage of systemic herbicides
Can reach underground storage organs and root systems and kill them preventing regrowth
What are fungicides
Chemicals used to control pathogenic fungi
Pesticides should be
Specific to pest concerned
Short life
Safe for human users
Pesticides can be
Toxic and persist in the environment
What is biosccumulation?
Term to describe the build up of a chemical in an organism
What is biomagnificstion?
An increase in the concentration of a chemical moving between trophies levels
