Because most agricultural practices in North America produce row after row of only a few, genetically identical, varieties of crops, the continent's food system rests precariously on a rapidly eroding genetic base, increasingly susceptible to pests and disease. As a possible solution, agricultural researchers, development experts, and policy makers are searching for for economic reasons, they are not always suited to preserving a diverse pool of crop genetics.
A recent study describes how generations of indigenous farmers relied on their understanding of practical genetics to develop hundreds of varieties of each indigenous plant cultivated. For example, long aware of the technique referred to now as hybridization, indigenous farmers frequently used the pollen from one variety of corn to fertilize another are less dependent on intensive irrigation systems because they have been selectively bred for particular environments.
Many of these heirloom varieties are preserved in household seed stocks by indigenous farmers who obtain seeds through long-standing family, community, and regional exchange networks; similarly, knowledge of the required development and cultivation methods has been maintained through the centuries by intergenerational exchanges within an oral tradition. Over the past century, however, the conservation of diverse crop genetics, thus bolstering the long-term sustainability of the continent's agricultural systems.
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