Mutagenesis in Plant Breeding Flashcards
The process by which an organism’s deoxyribonucleic acids (DNA) change, resulting in a gene mutation.
Mutagenesis
The net result of all that can go wrong with DNA during the life cycle of an organism” (Glickman et al.,1986). Thus, the types and amounts of spontaneous mutations produced are the resultant of all the cellular processes that are mutagenic and those that are antimutagenic.
Spontaneous (natural)
Mutation that arises from exposure of an organism’s DNA to a mutagen.
Induced (artificial/with the aid of agents)
Types of Mutation in terms of origin
Spontaneous and Induced
Types of Mutation According to the type of structural change produced:
Genomic mutation, structural mutation, gene mutation
Changes in chromosome number (gain or loss in complete sets of chromosomes or parts of a set).
Genomic mutation
Changes in chromosome structure (e.g., duplications of segments, translocation of segments).
Structural mutation
Changes in the nucleotide constitution of DNA (by deletion or substitution).
Gene mutation
Change of a dominant allele to a recessive allele
Recessive mutation
Change of a recessive allele to a dominant allele (a→A)
Dominant mutation
Mutations that convert the wild type (the common phenotype) to the mutant form (the rare phenotype)
Forward mutations
Those that change a mutant phenotype to a wild phenotype
Reverse mutations
Types of mutation based on cell type
Gametic and Somatic mutation
Consists of two genetically distinct tissues and may produce two distinct flowers on
the same plant
Chimera
Agents of artificial mutations
Mutagens
