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24: Variation and Plant Breeding

  • Page ID
    149526
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    Learning objectives

    By the end of this lesson you will be able to:

    • Identify the source and mechanisms that produce gametes.
    • Explain double fertilization and the production of a zygote, embryo, and other seed structures.
    • Contrast the difference between simple/qualitative and complex/quantitative inheritance and the basis of that difference.
    • Predict the types of F1 and F2 offspring expected when crossing two parents with known genotypes and phenotypes.
    • Understand how heritability is a measure of genetic influence, relative to other non-genetic influences.

    Plant propagation relies on gametogenesis for fertilization and the formation of fruit and seeds. Unlike asexual propagation, seeds from a single pollination can generation tremendous variation, depending on the diversity that exists within each parent. Geneticists take advantage of this diversity to understand how genes control the plant’s phenotypes and to make improved varieties that are tastier and have improved disease resistance.

    Thumbnail: Helleborus foetidus cross-section. Simon Garbutt. Public domain


    This page titled 24: Variation and Plant Breeding is shared under a CC BY-NC 4.0 license and was authored, remixed, and/or curated by Valeria Hochman Adler via source content that was edited to the style and standards of the LibreTexts platform.