BIOB38H3 Lecture Notes - Lecture 3: Plant Breeding, Fertile Crescent, Wild Type
Document Summary
9000 bc: first plant domestication, fertile crescent, no science known. (historical time) First time people knowingly crossed plants. (early renaissance) 1761-1766: hybrid offspring has traits from both parents. Create a hybrid species with both traits of parents. Important milestone in plant breeding and understanding genetics. 1944: dna is hereditary, one gene for one enzyme (modern techniques) 1972: recombinant dna technology was invented: selective breeding aka mass selection. Some mutants in a sea of wild type: pre-existing variation of traits where majority is wild type with a minority of mutants, heritability of traits and more/better food, conscious selection= farmers had to be aware of the environment. Wheat, barley, rice: non-shattering mutant: two genes control shattering. Naturally occurring recessive mutations: occurrence of mutants was low because it wasn"t beneficial for plants. Seed dispersal decreasing: wild type seeds fall by itself; low likelihood of seed dispersal. Selective breeding decreases seed dispersal in wild type plants.
