R2103 Flashcards
State what is meant by physical control and state two limitations and two benefits of this method of control
Physical control directly controls, destroys or blocks pest, weeds and disease or makes the environment unsuitable for it.
Benefits:
- Long lasting
- Little maintenance
Limitations:
- Some methods can be expensive
- unsafe use of equipment may cause potential hazard
Describe one example of physical control and how risks to people and environment can be minimised
Barriers: Using plastic membrane to reduce weeds, must be disposed of correctly (not burnt)
State what is meant by cultural control and state two benefits and two limitations of using this method of control
Cultural control involves manipulating or changing the growing environment to minimise effects of pest and disease. Benefits: - Unlikely to harm beneficial organisms -Can have long lasting effects Limitations: -Can be labour intensive -Time consuming
Describe one example of cultural control and how risks to people and environment can be minimised.
Cultivation; ploughing and rotavating soils to prepare for growing crops, this improves soil structure and drainage. To minimise risks the correct guidelines should be followed for operating ploughs, rotavators and other machinery to avoid damage to humans, animals and crops.
State what is meant by chemical control and state two benefits and two limitations of this method of control
Chemical control is the use of chemical substances intended to prevent or kill pests, weed and disease
Benefits:
-can be specific to pest/weed/disease problem
-Fast acting reducing problem quickly
Limitations:
-Damage to environment especially if used incorrectly
-pest and disease can build a resistance to chemicals.
Describe one example of chemical control and how risks to people and the environment can be minimised.
Using herbicides: Glyphosate; wear ppe, correct knowledge of use to avoid damage to other plants and aquatic life.
State what is meant by biological control and state two benefits and two limitations of this method of control
Biological control is the use of natural enemies/predators to reduce damage caused by pest and disease.
Benefits:
-No environmental damage or contamination
-Usually highly specific to a particular pest
Limitations:
-Can be expensive to start up
-May not completely remove/destroy pest problem
Describe one example of biological control and how risks to people and the environment can be minimised
Introducing predatory wildlife or insects. Incorrect application of biological control can lead to severe pest problem this can be minimised by understanding both pest and predators life cycle in order to achieve reliable control
Explain the importance of natural balance in plant protection
Creating natural balance helps to improve soil structure and minimise the use of harmful chemicals whilst still controlling and maintaining pest and disease. There are many ways to create natural balance; introducing wildlife and beneficial organisms, resistant and beneficial plants, good hygiene/house keeping, physical and cultural control.
Give two examples of how beneficial organisms can be encouraged
Planting beneficial plants, those that attract pollinators, and larger plants which may provide cover for nesting
Creating a pond to encourage frogs and toads to help keep pest populations down.
Give two examples of how garden practices can disturb natural balance.
Use of pesticides will decrease the number of beneficial organisms/natural predators, may cause damage to other plants and contaminate water sources.
Removing/ damaging areas which may have provided habitat for wildlife and insects may lead to an increase in pest populations.
Describe two methods that can be used restore and maintain natural balances to minimise the need for pesticide.
Integrated pest management which combines several approaches to pest control which is effective and environmentally friendly
Introducing crop rotation to improve soil fertility and structure and reduce or stop soil erosion.
Describe how the selection of plants can help to avoid plant problems
Choosing resistant cultivars may help to protect against pest and disease
Planting in suitable soil type to ensure healthy vigorous growth.
Describe two examples of an appropriate choice of plant for named situations
Plants suited to shade: Hosta Ferns Plants suited to Acid soil: Magnolia Rhododendron
Describe what is meant by a weed
A weed is a plant which is growing out of place
Describe the problems caused by weeds
- Weeds are often fast growing and invasive
- Compete with other plants for light, water and nutrients
- Can be visually unappealing
- can be host to harmful pest and disease
e. g: club root, white blister rust of Brassicaceae
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Describe the biology of an ephemeral weed and give two named examples
Ephemeral weeds have several generations during one growing season
Cardamine hirsute, Capsella bursa-pastoris
Describe the biology of an annual weed and give two named examples
Annual weeds complete life cycle in one year
can multiply through their seeds
Poa annua, Veronica persica
Describe the biology of a perennial weed and give two named examples
Can live for several years
spreads by both sexual and asexual means
Ranunculus repens, Aegopodium podagraria
Describe how weeds relate to horticultural situations such as ; recently cultivated soil herbaceous perennial borders Woody perennial plantings Lawns
Ephemeral and annual weeds a problematic on newly cultivated soil
Ephemerals and annuals can establish themselves in herbaceous borders
Perennial weeds are likely to survive and thrive in woody borders where soil is infrequently cultivated
Perennial, annual and ephemerals are all weeds that can be problematic in lawns
Describe how weeds can be controlled
Weeds are most easily controlled and maintained by the use of pesticides
Hand weeding
Knowledge of weed life cycle makes it easier to control and maintain weeds
State what is meant by contact herbicide
will kill/damage any plant in touches
kills only top growth not roots
affective for annual weeds
State what is meant by translocated herbicide
Absorbed by the plant and distributed around it in the sap
reaches all parts of plant
affective for perennials
State what is meant by Selective herbicide
Selective herbicides or plant specific
will affect certain plants but not others
Effective for use on lawns
Describe a situation where contact herbicide can be used appropriately
patios or driveways
Describe a situation where translocated herbicides can be used appropriately
woody borders
Describe a situation where selective herbicides can be used appropriately
lawns
State an active ingredient in a contact herbicide
Acetic acid
State an active ingredient in a translocated herbicide
Glyphosate
State an active ingredient in a selective herbicide
Dicamba
Explain why pest need to be controlled
Pests need to be controlled as they can often have a detrimental affect on plants
Some pests spread harmful pathogens
State what is meant by plant pest
insects and animals which have a detrimental effect on plants
Describe the damage done by rabbits
Eat most tender parts of plant- leafy veg particularly at risk
Strip bark from young trees which may cause death of tree
Describe the damage done by cabbage white butterfly larvae
Eat leaves of brassicas
can completely decimate a plant
lay eggs on underside of leaves
Describe the damage done by Black bean aphid
Feeds on the sap of wide range of plants
new growth can be weakened and distorted
Secretes honeydew which can cause fungal infection
Can be responsible for spreading virus
Describe the damage done by peach potato aphid
Feeds on the sap of tender, succulent plants in greenhouses
new growth of plants weakened and distorted
secrete honeydew which can cause fungal infection
Spread virus in potato crops
Describe the damage done by spider mite
attack large range of plants including fruits, vegetables and ornamentals
Sucking the cell contents of a plant reducing it’s capacity to photosynthesize
upper surface of leaves develop yellowish mottling
leaf may wither
Resistance to insecticides
Describe the damage done by Glasshouse whitefly
Sap sucking aphids found in greenhouses on underside of leaves
breed rapidly in the warm conditions
Secrete honeydew which may cause fungal infection
Describe the damage done by vine weevil
Larvae of vine weevil eat root system causing slow growth and leaf wilting
Lack of nutrients will cause plant to collapse and die
Adult vine weevil eat irregular notches from edges of leaves
Describe the damage done by slugs
Eat most parts of vegetables and herbaceous plants
leaving holes in leaves and other parts of plant
leave slime trails on soil and hard surfaces
Will eat seeds and tubers
Describe the damage done by Potato cyst eel worm
infest the roots of potatoes and tomato plants
feed both internally and externally sucking out cell contents
causes poor growth, yellowing/browning of leaves, severe infestation results in death of plant
Cyst are swollen bodies of fertilised females and contain hundreds of eggs
Describe method of feeding: Sap sucking/piercing
Sap feeding pests have needle like mouthparts which are inserted into plants in order to suck sap
no visible holes in leaves
many sap feeders have toxic saliva resulting in leaf distortion or discoloration
Can transmit virus
Pests: Black bean aphid,Peach potato aphid, spider mite, glasshouse whitefly, potato cyst eelworm
Describe method of feeding: Chewing
Chewing/biting pests are those that have teeth.
bite into leaves, stems buds, flowers and roots of plants
Damage includes holes in leaves and stems, discoloration of foliage, severed stems and leaves and wilting
Chewing pest: rabbit slugs snail vine weevil
Describe method of feeding Rasping
Scrape the surface of foliage, sucking fluid from top layer of cells until all green tissue is removed, leaving only skeleton behind
Rasping insects: Slugs snails mites
Describe the method of breathing used by insects
Air enters respiratory system through a series of external openings called spiracles
The spiracles lead to the internal respiratory system which is comprised of a dense network of tubes called tracheae
The spiracle openings allow air into the tracheal system, bathing the insects tissue with oxygen
Carbon dioxide is the metabolic waste which exits through the spiracle
-insects can control respiration to some degree
opening and closing spiracles via muscle contraction.
An insect in the desert for example, will keep spiracle valves closed to prevent moisture loss
Describe how knowledge of the life cycle of pests contribute to the success of their control
knowing the life cycle of a pest allows gardeners to control it at its most vulnerable point in the cycle or even avoid it all together.
State what is meant by plant disease
A plant disease is a pathological condition caused by bacteria, fungi or viruses
Describe the damage caused by grey mould and how it is spread
Widespread fungal disease affecting many varieties of fruit vegetables and ornamentals
primarily attacks buds and fruits making them inedible
Fluffy grey mould develops on the infected parts of the plant which then turn brown and rot
Spread: wind, water splash, pesticides
Describe the damage caused by strawberry powdery mildew and how it is spread
Leaf stems and buds coated with white powdery coating
leaves may turn yellow and drop prematurely
growth may be distorted
Spread: spread by spores carried long distances in the wind, can overwinter on leaves of remnant plants
Describe the damage caused by damping off and how it is spread
Rotting of seedlings caused by a number of fungi in the soil
most veg and bedding plants are susceptible
seedlings wither at base, eventually collapse and die
Spread: Fungal spores live in the soil . They can be transported on garden tools and in garden soils taken into the house or greenhouse
Describe the damage caused by honey fungus and how it is spread
A serious disease of woody plants and trees
Likely to lead to the death of the infected plant
Foliage may turn yellow brown
white fungal growth develops underneath the bark at the base of the plant
Spread: Black strands of fungus appear in the soil and may spread and affect other plants
describe the damage caused by rose black spot and how it is spread
Dark brown patches appear on leaves and may drop prematurely
plant is seriously weakened when left untreated
Spread: Black spot fungus produces spores in wet conditions and can be spread by rain splash
Can be passed from plant to plant on hands, clothing or tools
Describe the damage caused by Potato blight and how it is spread
Most serious disease of potatoes
Dark brown blotches on leaves which can be fringed with white fungus
The disease can spread quickly and cause whole foliage to collapse
Spread: Spreads through the air and develops in humid conditions
Lives in soil for up to 4 years
Describe the damage caused by clubroot and how it is spread
Roots become swollen and distorted
Leaves may wilt and have red/purple tint
Spread: spread by contaminated soil on plants, tools etc. Spores can rest in soil for up to 20 years.
Describe the damage caused by hollyhock rust and how it is spread
Fungal infection
rust takes nutrients from host plant causing general weakening of growth
orange brown pustules form on underside of leaves and yellow spots form on upper surface
Leaves may wither and fall prematurely
Disease starts on lower leaves and spreads upwards
Spread: Windborne spores and infected transplants Spores overwinter in the soil
Describe the damage caused by apple and pear canker and how it is spread
Caused by fungus and mainly attacks apples and pears
Bark cracks and dies increasing concentric rings leaving a marked scar
Cambium layer is killed and if the canker encircles the stem then it will cause it to die
Spread: Spores can move between wounds by wind, water splash, or insect.
Describe the damage caused by Fire blight and how it is spread
Bacterial disease which can decimate entire orchards
Affected areas appear blackened shrunken and cracked as though scorched by fire
Spread: Disease can be transmitted by insects rain or wind
Describe the damage caused by Bacterial canker on prunus and how it is spread
Bacterial canker affect trees of prunus
bacteria exists on leaves and can enter through stomata causing infections in young leaves
As leaves mature dead tissue drops out leaving holes in leaf
Spread: Infection spreads from leaves to wood and causes the canker to develop
Describe the damage caused by leaf curl virus and how it is spread
Virus infects potatoes and other members of solanaceae family.
severe infections reduce potato yields by 50%
Infection first shows in young leaves
Leaf margins become necrotic turning brown/purple and curl inwards towards center of leaf
Spread : The virus is primarily spread by peach potato aphid
Describe the damage caused by tobacco mosaic virus and how it is spread
Virus affects a wide range of plants especially tobacco
Infection causes characteristic patterns such as mosaic like mottling and discolouration on leaves
Spread: Virus can overwinter on infected plants and in the soil
State what is meant by term plant disorder
Disorders a plant problems not caused by pest or disease but by climate problems where a plant is growing or lack of nutrients
Describe how plants and growth are affected by frost
Cells freeze- as water expands on freezing, cells become ruptured and killed
Foliage is scorched and small plants may be killed
Buds can be damaged or killed reducing production of flowers and fruit
State one method of avoiding damage caused by frost
Provide protection such as horticultural fleece
Describe how plants and growth are affected by Shade
Etiolation
Long weak stems
smaller sparser leaves
chlorosis
State one method of avoiding damage caused by shade
Choose shade tolerant varieties
Describe how plants and growth are affected by drought
Foliage begins to wilt and turn brown and eventually die
Some plants may run to seed
Flowers and fruit may fail to set
Describe how to avoid damage caused by drought
Water regularly in dry conditions
Describe how plants and growth are affected by water logging
Oxygen cannot reach roots carbon dioxide cannot escape leaves turn yellow and start to wilt Growth may be stunted Toots may rot
Describe how to avoid damage caused by waterlogging
Improve soil structure
Describe how plants and growth are damaged by High/low temperature damage
Photosynthesis reduced and therefore plant growth reduced
Persistent high temps may scorch leaves and cause drought
Formation of flowers and fruit affected
Describe how damage caused by high/low temperatures can be avoided
Bring plants indoors or place in heated greenhouse for colder temperatures
Keep shaded during high temperature
Describe how to avoid damage cause by soil ph
Modify ph value in soil
Describe how plants and growth are damaged by fasciation
apical meristems become flattened and elongated
has appearance of many shoots compressed
Describe how to avoid damage caused by fasciation
Avoid injury to plant bases
Describe how plants and growth are damaged by rose balling
Although flower buds develop they fail to open
flowers become soft and slimy
flowers may drop
Describe how to avoid damage caused by rose balling
Improve air circulation
Describe two methods of avoiding the spread of virus
Keeping good hygiene in garden and greenhouse by cleaning tools and pots before and after use and washing greenhouse down regularly
Remove and burn infected plants
Explain how the knowledge of the life cycle of diseases contribute to the success of their control
Developing an understanding of the life cycle of disease enables a gardener to prevent and possibly stop the spread and development of disease on crops and ornamentals.
