Crops of the genus Lens have enriched diets and soils for millennia – but never before for so many. Global consumption has quadrupled since the 1960s.
History books often describe the first farmers of the Fertile Crescent sowing handfuls of primitive wheat and barley, but the lentil was just as important to the invention of agricultural life. Lentils provide everything that cereal crops don’t: huge concentrations of complementary protein, A and B vitamins and iron, as well as natural nitrogen fixation to maintain soil fertility.
Archaeologists have found lentils in prehistoric sites across West Asia, in the same regions where farmers continue to cultivate hundreds of thousands of hectares of the low, spindly plants. Since 7,000 BC, as lentils have circulated around the world, farmers have transformed their own landraces into a whole palette of colors and encyclopedia of uses, from the many-hued dals of South Asia to the peppery Le Puy lentils of France.
Other legumes have declined in per-capita consumption during the last 50 years, but not lentils: their global consumption has risen twice as fast as population growth. They are popular on the farm when soils are poor and drought is likely, and they are popular in the kitchen because they cook quickly – in the same time as a pot of white rice.
While lentils have seldom received top research priority, the collecting and ex situ conservation of their diversity began with the first genebank. Today a major international collection, along with national collections in lentil-growing countries, conserve the kaleidoscope of diversity found in landraces and wild relatives.
The first lentil collection was compiled by the famed botanist Nikolai Vavilov and his associates at the All-Union Institute of Agricultural Sciences in Leningrad, USSR in the 1920s and 1930s. Vavilov’s second wife, Elena Barulina, was the leading lentil researcher and made an extensive study of the collection, recognizing the great diversity of the crop and its wild relatives. The lentil was already becoming a neglected crop across industrialized Europe, and the collection saved many landraces before they vanished from the field.
Now part of the N.I. Vavilov Research Institute of Plant Industry, the first genebank retains an important global collection of lentils. The largest collection, meanwhile, is held in trust by the International Center for Agricultural Research in the Dry Areas (ICARDA) in Tel Hadya, Syria. The Crop Trust supports this international collection of more than 10,000 lentil accessions through an in-perpetuity grant. The material has also been securely backed up, with the rest of ICARDA’s genebank, above the Arctic Circle in the Svalbard Global Seed Vault, which holds further backups of lentil collections for eight other countries – including the Vavilov Institute’s.
As demand rises, lentils are sprouting up in new areas like the Canadian prairie and southern Australia. Breeders in these countries need genetic diversity to keep the crop thriving in new soil.
For these countries, trade opportunities have appeared at the same time as domestic interest from vegetarian and health-conscious consumers. With such a short history of cultivation, however, the countries rely on material from the rest of the world to adapt the crops to new regions. Drawing on many genebanks, they have stimulated renewed activity in lentil conservation and use.
In Canada, breeders faced a hurdle in protecting crops from the disease anthracnose. After screening 1,771 types of lentils, they found none that were resistant to an aggressive race of the fungus found in the country. Instead, they looked to the wider gene pool of wild species – and found the answer in a single plant of a wild relative called Lens ervoides. The breeders were able to introduce this rare resistance from the plant’s offspring into new lentil varieties.
Elena Barulina recognized the importance of lentil wild relatives when studying the first collection in Leningrad. However, wild relatives make up less than 1% of our collected lentil diversity. Through the Crop Wild Relatives project, the Crop Trust has supported an international effort to map the gaps in these collections and promote the ex situ conservation of wild diversity before it is lost to habitat destruction and climate change.
Despite the rising global profile, lentils remain a smallholder staple. 70% of the crop is grown for domestic consumption in developing countries. National research programs work with ICARDA and its genebank to make the crop an even stronger food security asset.
For many years, ICARDA researchers and their partners have used the diversity in their collections to make lentils stand up to drought, cold and disease. Drought tolerant varieties have been adopted around the Middle East and North Africa, and cold-hardy lines have brought the crop to formerly inhospitable parts of Central Asia. New material with traits from the Middle East and Argentina has doubled yields in South Asia since 1980.
One partner, the Bangladesh Agricultural Research Institute, released a series of improved varieties that were quick-maturing, high yielding and resistant to multiple major diseases. Despite the popularity of lentil farming in Bangladesh, the country had been obtaining more than half of the all-important protein source from imports. According to a 2009 study, the new varieties were planted on 110,000 hectares, and provide a million farmers with yield gains worth $38 million every year.
These new heights for an ancient crop are the result of advances and investment in breeding, but they are just as much a realization of the qualities that exist scattered across the lentil genome, teased out by farmers around the world for 10,000 years. Genebanks conserve the richness of that history and make it directly available to meet the needs of yet another millennium.