T3 plant disease Flashcards Preview

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Flashcards in T3 plant disease Deck (9)
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1
Q

how do aphids cause damage to plants

A

use their sharp mouthparts to extract sap from the plant phloem, weakening the plant

they are also vectors who can transfer pathogens from diseased plants to healthy plants

2
Q

how can we reduce the number of aphids

A

chemical pesticides

biological pest control - using ladybirds

3
Q

why do plants need a good supply of nitrate ions

A

required to convert sugars into proteins which are required for the plant to grow

as a result, the growth of the plant will be stunted if there is not an adequate supply of nitrates

4
Q

why do plants need a good supply of magnesium ions

A

required to synthesise chlorophyll, which absorbs light energy during photosynthesis

as a result, the leaves cannoT photosynthesise properly and they turn yellow (chlorosis)

5
Q

what are the symptoms of disease in plants

A
stunted growth (lack of nitrate ions)
spotted leaves 
decay/rotting
growths
malformation of stems/leaves
discolouration
presence of pests
6
Q

what are 3 ways in which plant disease can be identified

A

reference to gardening website or manual

laboratory testing

monoclonal antibody test kits

7
Q

give examples of physical defence responses used by plants

A

cellulose cell walls

tough waxy cuticle on leaves

outside later on stems/bark on trees

leaf fall

8
Q

give examples of chemical defence responses used by plants

A

antibacterial chemicals

poisons

9
Q

give examples of mechanical defence responses used by plants

A

thorns and hairs to deter animals

leaves that droop/curl on contact

mimicry to trick animals