Crop Domestication and Loss of Genetic Diversity

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What is crop domestication?

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Crop domestication is the process by which a plant's native characteristics are altered so that it cannot grow and reproduce without human intervention.

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What is co-evolution in the context of crop domestication?

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Co-evolution refers to the symbiotic relationship between plants and humans, where both evolve to suit one another's needs.

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What are the three stages of crop domestication?

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1. Pre-adapted wild plants colonize open ground around human habitation. 2. Seeds are regularly harvested and protected from herbivores. 3. Humans learn the timing of sowing and plant husbandry.

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What are some reductions or losses due to domestication?

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Loss of seed viability, protective coverings, shattering, seed dormancy, sturdiness, photoperiodic response, number of seeds, and resistance to abiotic stresses.

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What are some improvements or increases due to domestication?

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Increased adaptability, size of fruits, size of seeds, palatability, chemical composition, yielding ability, and uniform flowering.

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What is the technological drawback of improved crop varieties?

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Improved varieties eliminate the genetic resources upon which they are based.

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What has happened to genetic diversity over the past 10,000 years?

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Genetic diversity has been replaced with a relatively small number of varieties bred for high input agriculture.

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What are the consequences of agricultural practices on genetic diversity?

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Scarcity of land and agricultural practices lead to the disappearance of habitats that harbor wild progenitors and weedy forms of food plants.

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What is the risk associated with a narrow genetic base in crops?

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A narrow genetic base increases the risk of crop failure.

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What historical event exemplifies genetic vulnerability in crops?

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The Irish potato famine in the 1840s is a classic example of genetic vulnerability.