unit 3 KA3 - crop protection Flashcards
what do weeds compete with
crop plants
what may damage crop plants
pests and diseases
what factors can reduce the productivity of crop plants
weeds, other pests, and diseases
what are the properties of annual weeds
- rapid growth
- short life cycle
- high seed output
- long-term seed viability
what are the properties of perennial weeds (with competitive adaptations)
- storage organs
- vegetative reproduction
what are most of pests of crop plants
inverterbrate animals
what are examples of invertebrate animals
- insects
- nematode worms
- molluscs
what can cause plant diseases
- fungi
- bacteria
- viruses
what often carries fungi, bacteria and viruses
invertebrates
what are the cultural methods in order to protect crops
- ploughing
- weeding
- crop rotation
what do pesticides include
- herbicides to kill weeds
- fungicides to control fungal diseases
- inseciticides to kill insext pests
- molluscides to kill molusc pests
- nematicides to kill nematode pests
what do pesticides include
- herbicides to kill weeds
- fungicides to control fungal diseases
- inseciticides to kill insext pests
- molluscides to kill molusc pests
- nematicides to kill nematode pests
what are the two types of herbicides
selective and systematic
what are the advantages of using selective herbicides
they have a greater effect on certain plant species (broad leaved weeds)
what are the advantages of using systematic herbicides
they spread through vascular system of plant and prevent regrowth
how do systematic insecticides, molluscicides, and nematicides protect crops
they spread through the vascular system of plants and kill pests feeding on the plants
what are the problems with pesticides
- the toxicity to non-target species
- persistence in the environment
- bioaccumulation or biomagnification in food chains
- producing resistant populations of pests
what is more effective than treating diseased crops
applications of fungicides based on disease forecasts
what is bioaccumulation
the build up of a chemical in an organism
what is biomagnification
an increase in the concentration of a chemical moving between trophic levels
what is the control agent in biological control
- a natural predator
- parasite
- pathogen of the pest
what is integrated pest management
this is a combination of chemical, biological and cultural control
how can control of weeds, other pests and diseases be carried out
using biological control and integrated pest management
what are the risks with biological control
the control organism may become an invasive species, parasitise, prey on or be a pathogen of other species
