Selective breeding

Definition

Selective breeding is the process of intentionally mating plants or animals with desirable traits to produce offspring that exhibit those traits. This method allows for the enhancement of specific characteristics in a population, which can lead to improved agricultural productivity and the development of new varieties. By choosing parent organisms with particular attributes, such as higher yield or disease resistance, selective breeding has significantly influenced plant domestication and agricultural practices throughout history.

5 Must Know Facts For Your Next Test

1. Selective breeding has been practiced for thousands of years, dating back to ancient agriculture where early farmers chose seeds from the best plants for replanting.
2. This technique can lead to both positive and negative consequences, such as increased crop yields and reduced genetic diversity, respectively.
3. Selective breeding is often used to develop disease-resistant plant varieties, which are crucial in reducing losses due to pests and diseases.
4. It differs from genetic engineering, as it relies on traditional mating techniques rather than direct manipulation of an organism's DNA.
5. The success of selective breeding is heavily influenced by the selection criteria set by breeders, impacting future generations in terms of productivity and resilience.

Review Questions

• How does selective breeding contribute to agricultural advancements and what are some specific examples of traits that are typically enhanced?
  • Selective breeding plays a crucial role in agricultural advancements by allowing farmers to enhance specific traits that improve crop yield, nutritional value, or resistance to pests. For instance, breeders may focus on developing plants that are drought-resistant or have higher protein content. By selecting parent plants that exhibit these desirable traits, they can create new varieties that are better suited for changing environmental conditions or market demands.
• Evaluate the potential risks associated with selective breeding practices in plant cultivation.
  • While selective breeding can lead to significant benefits like increased crop production, it also carries risks such as reduced genetic diversity among plants. This lack of diversity can make crops more susceptible to diseases and pests since a uniform population may not have varied defenses. Additionally, over-reliance on specific varieties can lead to vulnerabilities in the food supply if those varieties fail due to unforeseen environmental challenges.
• Synthesize information on how selective breeding techniques differ from modern biotechnology approaches like genetic modification and discuss their implications for agriculture.
  • Selective breeding techniques involve traditional methods of choosing parent plants with desirable traits to reproduce over generations, while modern biotechnology approaches like genetic modification involve directly altering an organism's DNA. The implications for agriculture differ greatly; selective breeding often requires multiple generations to achieve desired traits and can be limited by existing genetic variation. In contrast, genetic modification allows for more rapid changes and introduction of traits that may not be present in the gene pool. However, both methods raise important considerations regarding sustainability, ethics, and food security.

Related terms

Hybridization: Hybridization is the process of crossing two different species or varieties to produce offspring with combined traits from both parents.

Genetic diversity: Genetic diversity refers to the total number of genetic characteristics in the genetic makeup of a species, which is essential for resilience against diseases and environmental changes.

Phenotype: Phenotype is the observable physical or biochemical characteristics of an organism, resulting from the interaction of its genotype with the environment.