plant disease

Cards (9)

give three examples of plant disease
tobacco mosaic virus
rose black spot(fungus)
blight(caused by protist)
five ways to identify plant disease
stunted growth
spots on leaves
areas of decay
malformed stems and leaves
discolouration
why is it important to control disease
destroys crops
knock on effect higher up the food chain as plants are producers
how does aphid infection affect plants 
feeds on phloem sap and releases turgor pressure making the leaf wilt
sticky honeydew which encourages mould growth
could carry disease and infect
holes left from aphid can cause secondary infection
nitrate deficiency 
stunted growth
magnesium deficiency 
yellow leaves
why does a nitrate deficiency cause stunted growth 
because nitrate is needed to make amino acids which are used during protein synthesis which is used for growth
why does a magnesium deficiency cause yellow leaves 
because magnesium is needed to make chlorophyll which makes the plant green
name 5 plant defences
pheromone release
cellulose cell walls
tough waxy cuticle
mimicry
leaves that droop and curl when touched