Cultivars and Plant Propagation

Study Notes

A cultivar is a set of cultivated individuals with important agricultural properties that maintain their characteristics after multiplication.
The cultivar is based on criteria of individuality, homogeneity, and stability.
Cultivars can be classified under agricultural, botanical, and genetic aspects.
From a genetic point of view, cultivars can be pure line, pure variety, multiline variety, local population, synthetic cultivar, hybrid, polyploid cultivar, clone cultivar, or cultivation mix.
A breeder's choice for a cultivar's genetic constitution is based on factors such as mode of reproduction, biology of flowering, life span, agroecological conditions, and market requirements.
Autogamous plants have cultivars made up of homozygous genotypes, while allogamous plants have homozygous lines obtained after inbreeding.
Pure lines are difficult to maintain due to natural mutations, incidental hybridizations, and mechanical seed mixtures.
Pure varieties are groups of similar genotypes that result from choosing elite plants in segregating populations.
Homogeneous varieties are close to perpetual homozygosity, while polymorphic varieties show residual heterozygosity.
Multiline cultivars are made up of several lines with different resistance genes to different pathogens.
Multiline cultivars are designed to control pathogen attacks.
Almost isogenic lines are obtained through backcrossing with recurrent parents.
Seed production for multiline cultivars requires monitoring for pathogen distribution and new breeds.
Synthetic cultivars are formed through interpollination of genetically differentiated lines or clones.
Hybrid cultivars consist of F1 hybrids resulting from controlled crossing of parental forms.
Polyploid cultivars have a genetic constitution dependent on ploidy level and initial material.
Cultivation mixtures are mechanical mixtures of two or more cultivars used for sowing.
Clone cultivators are found in many species where vegetative multiplication is possible.
Stability is ensured in clone cultivators through vegetative multiplication.
Reduced genetic variability in clone cultivators can limit their potential.
Genetic alteration is reduced in tissue culture propagation.
Somaclonal variability can cause deviation from typicality in planting material.
Somatic mutations contribute to somaclonal variability.
Biological purifications can eliminate negative effects of somaclonal variability.
Elite plants can be chosen to reduce somaclonal variability.
Somaclonal variability is a significant cause of deviation in planting material production.
Tissue culture propagation is a reliable method for producing planting material.
Genetic alteration can be controlled in tissue culture propagation.
Biological purifications are effective in reducing negative effects of somaclonal variability.
Somaclonal variability can be reduced by selecting typical elite plants.

Description

Do you know the different types of cultivars and how they are classified? Are you aware of the factors that influence a breeder's choice for a cultivar's genetic constitution? Test your knowledge on cultivars with this quiz and learn about pure lines, pure varieties, multiline varieties, local populations, synthetic cultivars, hybrids, polyploid cultivars, clone cultivars, and cultivation mixtures. Also, find out about the different methods used for producing planting material, including tissue culture propagation and