Unit 3.4: Plant and Animal Breeding Flashcards
What are the desirable qualities of plants?
- Higher yield
- Higher nutritional value
- Pest resistance
- Wide environmental range
What are the desirable qualities of animals?
- Higher meat yield
- Body composition
- Disease resistance
- Size
What are 3 requirements of Plant field trials?
- Selection of treatments - the number of treatments and if they are valid to compare
- Number of replications - generally the more the better to take account of variability within the sample
- Randomisation if treatments - ordering of plants should be random to eliminate bias
What is interbreeding?
Interbreeding means individuals breed within a particular gene pool. In interbreeding selected related plant and animals are bred for several generations until the population breeds true
What is interbreeding depression?
Occurs when there is an increase in frequency of individuals who are homozygous for recessive deleterious alleles. These will do less well at surviving to reproduce
What is cross breeding?
Introducing new alleles into a population can be achieved by cross breeding to produce a population with improved characteristics
The two parent breeds must be maintained to produce more cross red animals showing this characteristic
What is hybrid vigour?
The 1st generation had characteristic of both parents and often this means they are more ‘vigorous’. They may have increased disease resistance of increased growth rate
The F1 will be a uniform group of heterozygotes, breeding to the F2 will produce too much variation, so less controlled production
What is genetic Technology?
Genomic sequencing- allows identification of desirable genes for use in breeding programmes
RDT- Breeding programmes can involve crop plants that have been genetically modified using RDT
RDT examples - insertion of Bt toxin gene intoplangs for pest resistance. Glyphosate resistance gene inserted for herbicide tolerance
