Communicable Disease, Prevention and Immunity - Plant Disease Flashcards
what are the plant diseases you need to know
- ring rot
- tobacco mosaic virus
- potato/tomato late blight
- black sigatoka
what plants does ring rot affect
potatoes, tomatoes, aubergines
what type of microbe causes ring rot
bacteria
how is ring rot transmitted
- can spread from diseased to healthy tubers by direct contact
- indirect contact from contaminated wash water, soil, or equipment
- potato beetles and aphids can act as vectors
how is ring rot treated
- no effective methods currently available for chemical or biological control
- destroy infected crops and potato sacks
how is ring rot prevented
- sanitise equipment and storage facilities
- only plant certified seeds
- reduce insect pests
what plants does TMV affect
tobacco plants, tomatoes, peppers
what type of microbe causes TMV
virus
how is TMV transmitted
- direct contact
- indirectly on workers’ hands, clothing or on tools (formites)
how is TMV treated
no cure for TMV, diseased plants should be dug up then burnt
how is TMV prevented
- sanitise equipment and storage facilities
- use resistant crop strains
what plants does potato/tomato blight affect
potatoes, tomatoes
what type of microbe causes potato blight
protoctist
how is potato blight transmitted
- mainly spread via resistant spores which travel in wind/water until they land on a susceptible plant and weather conditions are right for it to develop
- direct contact
- aphid vectors
how is potato blight treated
no cure
how is potato blight prevented
- burn infected plants
- use resistant strains
- careful management can reduce risk
what plant does black sigatoka affect
bananas
what type of microbe causes black sigatoka
fungus
how is black sigatoka transmitted
- spores can spread in the wind or by rain splash and irrigation water
- spores can germinate more quickly in humid conditions
- fungus can spread from tree to tree by leaves directly touching
how does the fungus enter the leaf
through stomata pores
how is black sigatoka treated
fungicide treatments can control spread, but no cure
how is black sigatoka prevented
remove diseased leaves and prune branches to improve air circulation
Why do bacteria and fungi often live in the vascular tissue of plants
- obtain sugars from phloem
- obtain water from xylem
