Sign up to access the complete lesson and track your progress!
Unlock This CourseSelective breeding has been used by humans for thousands of years to improve crops and livestock. Today, we combine traditional breeding methods with modern biotechnology to create more efficient and targeted breeding programmes. These programmes are carefully designed to achieve specific goals, whether that's increasing crop yields, improving disease resistance, or enhancing nutritional content.
Key Definitions:
Plant breeding programmes typically focus on improving yield, disease resistance, nutritional content and environmental tolerance. Modern programmes use DNA analysis to identify plants with desired genes before they even flower.
Creating a successful breeding programme requires careful planning and clear objectives. Breeders must consider what traits they want to improve, how long the programme will take and what resources are available. The process involves several key stages that must be followed systematically.
Every successful breeding programme follows a structured approach that maximises the chances of achieving the desired outcomes whilst minimising time and resources.
Define clear, measurable objectives. For example: "Increase wheat yield by 15% whilst maintaining disease resistance." Specific goals help guide all subsequent decisions.
Choose breeding stock with the best combination of desired traits. Modern programmes use genetic testing to identify the most promising candidates before breeding begins.
Plan the crossing programme, including which organisms to breed together and in what order. Consider factors like generation time and population size.
In the 1960s, Norman Borlaug designed a breeding programme that created high-yielding, disease-resistant wheat varieties. His systematic approach involved crossing Mexican wheat with Japanese dwarf varieties, then selecting the best offspring over multiple generations. This programme helped prevent famine and earned Borlaug the Nobel Peace Prize.
Today's breeding programmes increasingly rely on biotechnology tools that make the process faster and more precise. These technologies allow breeders to identify desired genes without waiting for plants to grow or animals to mature.
Modern breeding programmes use several cutting-edge technologies that would have seemed like science fiction just a few decades ago. These tools are revolutionising how we improve crops and livestock.
This technique uses DNA markers to identify plants or animals with desired genes. Instead of waiting years to see if a crop is disease-resistant, breeders can test seedlings in the laboratory and know immediately which ones carry resistance genes.
Advanced computer programmes analyse thousands of genetic markers across an organism's entire genome. This creates a "genetic score" that predicts how well an individual will perform, even before it's fully grown.
Breeding programmes are used across agriculture to solve real-world problems. From developing drought-resistant crops for climate change to creating livestock with better welfare characteristics, these programmes have immediate practical benefits.
Scientists designed a breeding programme to create rice enriched with vitamin A precursors. The programme combined traditional breeding with genetic engineering to address vitamin A deficiency, which causes blindness in developing countries. The project took over 20 years but has the potential to save millions of lives.
Animal breeding programmes face unique challenges compared to plant breeding. Animals have longer generation times, smaller family sizes and more complex care requirements.
Modern dairy programmes focus on milk yield, disease resistance and longevity. Artificial insemination allows the best bulls to father thousands of offspring worldwide.
Chicken breeding programmes have dramatically improved egg production and meat quality. Modern laying hens produce over 300 eggs per year compared to 150 for their ancestors.
Sheep programmes often focus on wool quality, meat production and adaptation to local climates. Some programmes have developed breeds resistant to specific parasites.
Whilst breeding programmes offer many benefits, they also raise important ethical questions. We must consider animal welfare, genetic diversity and the long-term consequences of our breeding decisions.
Intensive breeding can reduce genetic diversity, making populations vulnerable to new diseases. Successful programmes must balance improvement with maintaining genetic variation.
Modern breeding programmes must carefully consider their broader impact on society and the environment. This includes thinking about sustainability, accessibility and unintended consequences.
Breeding programmes that focused solely on rapid growth created chickens that grow so fast their legs cannot support their weight. Modern programmes now include welfare traits like walking ability and heart health alongside production traits.
The future of breeding programme design will likely involve even more sophisticated biotechnology tools, including gene editing and artificial intelligence. These technologies promise to make breeding programmes faster, more precise and better able to address global challenges like climate change and food security.
Future breeding programmes will focus heavily on developing crops and livestock that can thrive in changing climatic conditions, including higher temperatures, altered rainfall patterns and new pest pressures.