Smallholder farmers overwhelmingly save their own seed, maybe getting a bit extra from relatives, friends, neighbours and, very occasionally, further afield. If climate change is going to affect growing conditions — and it is — will the so-called informal sector be able to supply them with material that can thrive in the new conditions?
A new study suggests that, at least for smallholder maize farmers in eastern Mexico, getting seeds that will cope with climate change might not be too much of a problem. Mauricio Bellon of Bioversity ((Who, in the interests of transparency, is my day-job boss.)), and his colleagues David Hodson of FAO and Jon Hellin at CIMMYT, wondered where Mexican maize farmers got their seed and how climate change might affect their environment. ((Bellon, M.R., Hodson, D., & Hellin, J. (2011). Assessing the vulnerability of traditional maize seed systems in Mexico to climate change Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.1103373108)) So they asked farmers in 20 communities in four different agro-ecological zones: wet lowland, dry lowland, wet upper midaltitude, and highland.
Across all the zones, most of the seed lots are saved by the farmers from their own fields. Less than a third comes from off the farm, and most of that is from family, neighbours and friends. Very little comes from shops, government programmes, or strangers. But the system is by no means static. A quarter of the farmers said that they experimented with farmer landraces or modern varieties from further afield. Highland farmers are especially likely to experiment.
The rate of retention is low, however, particularly for improved varieties, suggesting that farmers know about improved varieties, have tested some of them, and have found them wanting.
Farmers get more than 90% of all seed lots within 10km of the community. The same goes for altitude. Almost all seed lots come from less than 50 metres higher or lower than the farm. The fact that farmers get their seed very locally, with little recourse to outside material, suggests that what they have locally is well adapted to local conditions. So how much will those conditions change?
Again, the scientists asked, not farmers but as many climate models as they could get their hands on. All the models predict that it will get dryer and hotter in the study areas. When the researchers looked in detail at how conditions in 1 km square “pixels” within the 10 km radius around the communities changed, they found that except in the highland communities, “the predicted future maize environments already are present within the 10-km radial zones and … the average distances to the predicted novel environments are relatively short”. Bottom line?
[F]armers should have relatively easy access to planting material adapted to the agro-ecological conditions predicted under climate-change scenarios.
In the highlands, however, things will not be so simple. Conditions for maize change most in the highlands, with more land becoming unsuitable and probably greater fragmentation of maize-growing areas. Traditional seed systems are unlikely to be able to provide the kinds of varieties farmers there will need, but those farmers also have a history of obtaining and experimenting with seed lots from further afield.
Researchers and extension workers should perhaps concentrate their efforts to help farmers prepare for climate change in those highland areas.
Having shown that the seed supply for one crop in one region is not as vulnerable to climate change as might have been expected, the big question is: how general might this be? Roughly half the highland maize grown in the developing world is outside Mexico. Farmers there will need to prepare too. And many other crops important to smallholder farmers are sourced through traditional, informal seed systems. As the authors note:
This approach, based on quantifying the spatial scope of traditional seed systems and relating these spatial scopes to potential climate shifts that would modify the distribution of growing environments and hence the fit between the germplasm to which farmers currently have access to and the one needed in the future, can be applied to different systems and circumstances, although the specifics probably will vary from one case to another.
How soon might those additional studies happen?