Genetic Technologies in Agriculture
- Junessa Masaya
- Apr 16
- 4 min read
HSC Biology | Study Notes
Genetic technologies in agriculture are a key part of NSW Biology Stage 6, Module 6, Genetic Change. This topic matters because Module 6 specifically requires students to evaluate the benefits of using genetic technologies in agricultural applications and to evaluate the effect on biodiversity of using biotechnology in agriculture. The syllabus also includes the development of transgenic organisms in agricultural applications.
In this lesson
what GM crops are
how genetic technologies can improve disease resistance
how selective breeding is used in agriculture
the benefits of these technologies
biodiversity concerns linked to agricultural biotechnology
Why genetic technologies are used in agriculture
Agriculture uses genetic technologies to:
increase yield
improve resistance to pests and disease
produce more reliable crops and livestock
improve food supply
The Module 6 syllabus specifically links biotechnology to agriculture and asks students to evaluate both benefits for society and effects on biodiversity.
GM crops
GM crops are crops that have been genetically modified by inserting genes into their genome.
What this means
A gene from one species can be inserted into another species to give the crop a useful trait.
This is a form of recombinant DNA technology.
HSC example
A 2024 HSC marking guideline gives Bt corn and Bt cotton as examples of plant biotechnology using recombinant DNA technology.
Why GM crops are used
GM crops can be designed to:
resist insect pests
improve survival in difficult conditions
increase productivity
Disease resistance
One major agricultural aim of genetic technology is improving disease resistance or resistance to pests that damage crops.
Crop examples
A Year 12 problem set states that genetic technologies in agriculture can produce disease- and pest-resistant crops, reducing the need for pesticides or other expensive treatments.
HSC example
A 2020 HSC marking guideline explains that Bt corn is produced by taking a gene from Bacillus thuringiensis. The gene codes for a protein toxic to the European corn borer, reducing disease or damage in corn crops.
Why this matters
Disease- or pest-resistant crops can:
reduce losses
improve yield
lower chemical treatment costs
help increase food production
Selective breeding
Selective breeding is when humans choose which plants or animals reproduce in order to increase favourable traits in the next generation.
What this means
Individuals with useful characteristics are chosen as parents.
Over generations, these traits become more common.
HSC agricultural example
A 2024 HSC marking guideline gives hybridisation of dairy cows to produce greater milk-yielding cows as an example of agricultural biotechnology.
Why selective breeding is useful
Selective breeding can be used to improve:
milk yield
crop yield
growth rate
disease resistance
product quality
GM crops and selective breeding compared
Technology | What it does | Example |
GM crops | Inserts genes to produce a new trait | Bt corn, Bt cotton |
Selective breeding | Chooses parents with desirable traits | High milk-yield dairy cattle |
Benefits of genetic technologies in agriculture
Higher yields
A Year 12 problem set states that genetic technologies in agriculture can produce a greater yield of crop to feed people.
Why this matters
Higher yields can:
increase food availability
improve farm productivity
support a growing human population
A 2024 HSC marking guideline also links Bt corn and greater milk yield to the production of more food for society.
Better resistance
Disease- and pest-resistant crops can:
survive better
reduce crop losses
reduce reliance on pesticides or costly treatments
Economic benefits
The 2024 HSC marking guideline states that agricultural biotechnology can lead to greater yields for farmers, resulting in increased profits and improved quality of life for farmers.
Biodiversity concerns
Module 6 does not only ask students to describe benefits. It also specifically asks them to evaluate the effect on biodiversity of using biotechnology in agriculture.
Reduced genetic diversity
A major concern is that using only a few highly successful crop varieties or breeding lines can reduce the gene pool.
A Year 12 problem set explains that if only the most successful cross is commercially produced, the gene pool can be reduced because that new favourable variety may be grown widely at the expense of other varieties.
Why this matters
Reduced genetic diversity can make agricultural populations:
less flexible in changing conditions
more vulnerable to new disease or pests
more genetically uniform
Limited access and inequality
A 2024 HSC marking guideline notes that Bt corn seeds must be purchased each season, while normal corn seeds can often be regrown from previous crops. It explains that this can create inequalities in who has access to GM seeds and the markets linked to them.
Effects on animal welfare
The same 2024 HSC marking guideline notes that continuously selecting dairy cows for greater milk yield has been linked to decreased fertility and may affect quality of life for the cows.
Why this matters
This shows that agricultural technologies can have:
biological consequences
ethical implications
trade-offs between productivity and welfare
Important balance
Genetic technologies in agriculture can clearly be useful, but they also need to be judged carefully.
A strong Module 6 answer should show both sides:
benefits, such as yield and resistance
concerns, such as reduced biodiversity and ethical issues
Worked example
Exam-style question
Explain one benefit and one biodiversity concern linked to genetic technologies in agriculture.
Worked answer
One benefit is that GM crops such as Bt corn can resist insect pests, reducing crop losses and increasing food production. One biodiversity concern is that if one successful crop variety is widely grown, the gene pool may be reduced because fewer different varieties remain in use.
Why this works
This answer:
gives one clear agricultural benefit
gives one clear biodiversity concern
uses named examples from HSC material
Common mistakes
Treating all agricultural genetic technologies as GM crops.
Forgetting that selective breeding is also an agricultural biotechnology.
Describing yield benefits without mentioning biodiversity concerns.
Saying GM crops always increase biodiversity.
Ignoring the ethical and economic implications of access and animal welfare.
Quick quiz
What is a GM crop?
How can genetic technologies improve disease or pest resistance?
What is selective breeding?
Give one agricultural benefit of genetic technologies.
Why can agricultural biotechnology reduce biodiversity?
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