Unit 3 - Detection and identification of plant diseases Flashcards
State the name of a type of insect that attacks plants
Plants can also be attacked by insects such as aphids
Complete the sentence
Plants can also be attacked by insects such as ______
Plants can also be attacked by insects such as aphids
What do aphids do
Aphids extract nutrients such as sugars from the plant, stunting its growth
State a feature found on an aphid - how does this help them do their job
Aphids have long sharp mouthpieces that penetrate into the phloem vessels of the plant so they that they can feed on the sugar-rich phloem sap
State two things that insect pests can do to a plant
Insect pests may both destroy plants directly or act as vectors of disease
State the number of aphids that can infest a plant, how is this a problem
They can infest a plant in large numbers and remove large quantities of the phloem sap. This can weaken the plant.
Also they deprive the plant cells of the products of photosynthesis. This can weaken and damage the plant.
Aphids can act as ______ for the transfer of diseases
Aphids can act as vectors for the transfer of diseases
What is a vector
A vector is an organism that transmits disease
What can be done to control the infestation of aphids
Biological pest control (using ladybirds, a natural predator of the aphid) to feed on them
Using chemical pesticides are the best ways to control infestation with aphids
How can plant diseases be detected (symptoms of plant diseases)
Plant diseases can be detected by:
* stunted growth
* spots on leaves
* areas of decay (rot)
* growths
* malformed stems or leaves
* discolouration
* the presence of pests
State an example of a plant disease where stunted growth may be seen
Stunted growth
Rose Black Spot
Tobacco Mosaic Virus
Nitrate deficiency
State an example of a plant disease where spots on leaves may be seen
Spots on leaves
Rose Black Spot
State an example of a plant disease where areas of decay (rot) may be seen
Areas of decay (rot)
Rose black spot
Blights on potatoes
State an example of a plant disease where the presence of visible pests may be seen
Presence of visible pests
Aphids
Caterpillars
State an example of a plant disease where discolouration of the leaves may be seen
Discoloration
Chlorosis in magnesium deficiency
Mosaic patterns resulting from Tobacco Mosaic Virus
State an example of a plant disease where growths may be seen
Growths
Crown galls caused by bacterial infections
State an example of an instance where Malformed stems and leaves be seen
Aphids infestation
Caterpillars infestation
What should be done if a plant disease cannot be treated
If a plant disease cannot be treated, remove the disease plants as quickly as possible to prevent the pathogens spreading through the garden, field of woodland
How can plant diseases be identified
Diseases in the garden can be identified by comparing the symptoms in the living plant with disease descriptions in a gardening manual or online
When the symptoms of disease occur in crop plants or forest trees, experts may visit the field or woodland to observe the symptoms in their natural environment. They may then take samples of diseased materials to the laboratory to identify the pathogen using techniques that include DNA analysis.
Plant scientists, foresters, farmers and market gardeners can use testing kits that contain monoclonal antibodies to identify the presence of certain plant pathogens (for example, the fungal pathogen Botryis)
State an example of non-communicable disease in plants
Non-communicable disease in plants
Mineral deficiency - they are not passed from one plant to another
Complete the sentence
Plants need the correct amount of _____ to function properly
Plants need the correct amount of nutrients to function properly
What could be a solution to if a plant is deficient in a certain type of mineral
If plants are deficient in a mineral these can be replaced by fertilisers added to the soil
These fertilisers are often shown as NPK ratios depending on the need of the plant that is being grown
State the different types of mineral deficiencies found in plants
Nitrate deficiency
Magnesium deficiency
Potassium deficiency
State the use of nitrates in plants
Nitrates - production of amino acids for proteins
State the use of magnesium in plants
Magnesium - Synthesis of chlorophyll. Chlorophyll is needed for photosynthesis
State the symptoms of nitrate deficiency
A lack of the nitrate ion causes stunted growth. This is because nitrate is needed for protein synthesis and therefore growth.
State the symptoms of magnesium deficiency
Yellowing leaves (chlorosis) due to less chlorophyll and stunted growth
A lack of the magnesium ion causes chlorosis, because magnesium is required to make chlorophyll.
What is chlorosis
Chlorosis is the yellowing seen on the leaves of plants when they cannot make chlorophyll due to a lack of magnesium ions.
