Abstract: Crop wild relatives, the progenitors and kin of domesticated crop species, promise breeders a potent weapon against climate change. Having evolved outside the pampered environs of farms, wild relatives tend to be more rugged to survive temperature, salt, floods, and drought—all the extremes characteristic of a warming planet. But who will benefit from re-wilded crops? What kinds of agricultural systems will they tend to support? And can wild relatives be protected before they are lost under pavement, desertification, and expanding industrial farms? In this essay, I explore different visions of conservation and use for crop wild relatives. With CWR valued at an estimated $115–120 billion to the global economy annually, many researchers suggest ancient germplasm can be harnessed to feed billions in a warming world. Others look more closely at ancient customs and farmer knowledge that have long promoted conservation of wild species within and around cultivated landscapes. By intentionally planting crops at field borders, farmers also perform “in vivo” breeding. I conclude that wild relatives hold much potential to reinfuse diversity into eroded crop gene pools, providing greater systemic resilience. But unless we consider who controls seeds, intellectual property, and wild and agricultural lands, CWR innovations will only prop up an agriculture that ultimately undercuts crop and wild relative renewal.
Not long ago, Native Seed Search, a Tucson-based organization dedicated to preserving indigenous crop varieties, was approached by representatives from Monsanto. Did Native Seed have any samples of teosinte they were willing to sell? The wild ancestor from which domesticated corn was bred, teosinte is scarcely recognizable as a kin of modern corn, the latter with its multiple rows of kernels, plump and sweet. Yet it is in the genes of this wild relative – and those of all the world’s major crop species – that modern plant breeders are eager to find a potent weapon against climate change.
Having evolved outside the pampered habitat of a farm, wild relatives are hardier than most domesticated species. Their traits, say researchers, could potentially be bred or engineered into crops to produce climate-hardy varieties. If you have not yet heard that “weeds will feed the world,” you soon will.
But who will benefit from such wild relative improvements? What kinds of agricultural systems will they go to support? And how to stanch the loss of wild relatives due to climate change, urbanization, deforestation, pollution – and industrialized agriculture itself?
With such questions still waiting to be satisfyingly addressed, much wild relative work is already underway. Scientists at the United States Department of Agriculture are looking to red rice, a weedy relative of domesticated rice (genus Oryza), for genes that could make commercially grown varieties more heat-resistant, adapted to saltier soils, and higher yielding even under the driest conditions (Palmer 2014). Other USDA researchers are crossing the countryside in search of wild relatives of sunflower (Helianthus), one of the few domesticated plants native to North America (Harvey 2015). Similar research at CIMMYT in Mexico, the cradle of Green Revolution research, focuses on relatives of wheat (Triticum), with advances in drought- and heat-resistant traits already resulting in edible grain.