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Updated: Jul 8, 2026
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High-throughput, Microscale Protocol for the Analysis of Processing Parameters and Nutritional Qualities in Maize (Zea mays L.)
Published on: June 16, 2018
A crop population perspective on maize seed systems in Mexico
George A Dyer1, J Edward Taylor
1Department of Agricultural and Resource Economics, University of California, One Shields Avenue, Davis, CA 95616, USA. gdyer@primal.ucdavis.edu
Summary
Maize evolution in Mexico is driven by farmers integrating new seeds into local stocks. This process, influenced by social factors and perceived value, shapes maize diversity and can lead to loss or maintenance of genetic resources.
Area of Science:
- Agricultural Science
- Genetics
- Sociology
Background:
- Maize evolution in Mexico is traditionally attributed to artificial selection of local germplasm.
- This view overlooks the significant social and technological factors influencing maize diversity.
Purpose of the Study:
- To investigate the role of farmer-led technological diffusion and appropriation in maize evolution.
- To model the demographic processes underlying seed population dynamics and diversity maintenance.
Main Methods:
- Theoretical modeling using a demographic approach to seed life history.
- Analysis of Mexico-wide data on maize germplasm introduction and diffusion.
- Empirical estimation of nonlocal seed introduction and spread rates.
Main Results:
- Farmer-led maize evolution is driven by selective integration of nonlocal germplasm into local seed stocks.
- Management practices create population structures influencing subpopulation spread or extinction, independent of agronomic traits.
- Introduction of nonlocal seed is less frequent than assumed, with rapid replacement limiting spread, yet valuable introductions contribute to diversity.
Conclusions:
- Maize seed dynamics and evolution are complex social processes, not solely driven by selection on local varieties.
- Farmers' desire to appropriate value in farming influences seed appropriation and diffusion, impacting maize diversity.
- Nonlocal germplasm can be critical for maintaining diversity in local maize populations, despite challenges in its adoption and spread.
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