The "perennial grain" story seems to pop up every few months. The basic idea is that perennial crops would have higher yields and lower environmental impacts than their annual kin.
The picture on the left explains pretty clearly why - large permanent root systems secure the topsoil, exhaustively scavenge water and nutrients and support more vigorous shoot growth over a longer season.
This week, it's perennial maize.
One thing that I think is funny about these stories is that they inevitably herald the accompanying freedom from multinational seed companies. Aside from the fact that no farmer's forced to buy seed, I don't see any reason why companies wouldn't jump on a perennial grain bandwagon.* Companies like Monsanto are already selling/developing advanced varieties (e.g. Bt/Roundup) of perennial crops like alfalfa and sugarcane.**
Companies don't have to sell seed every year to make money. In this case, I've heard they'll be offering an annual license agreement (e.g. you buy the seed the first year and pay a license fee each following year that you continue to cultivate the crop). I think it shows a lack of creativity that people always pin the blame on what they don't like about the state of agriculture on the "need" for companies to sell seed every spring. There're lots of ways to do business.
Which isn't to say I'd expect companies to make the initial investment - jumpstarting speculative new technologies and industries is the role of governments and non-profits. According to Ed Buckler (in the article), an easy $15-30 million should do this. This is an inconsequential speck in the U.S. budget and we should probably just get it done.
h/t: Agricultural Biodiversity Weblog
* I heard that a coalition of wheat farmers actually petitioned companies like Monsanto to begin reinvesting in transgenic wheat varieties since wheat yields have fallen so far behind other crops like maize.
** Pest and herbicide resistance is particularly valuable in perennial systems as bugs and weeds tend to build up over years without tilling or rotation.
*** It might also be a concern how you can maintain a high genetic gain in yield year-by-year and decade-by-decade when you switch an annual to a perennial, but I imagine the gains inherent to perennialism paired with our incredible current breeding technology should make this well worth it.
Another interesting aspect of switching to perennial crops would the potential to switch to clonal cultivars. Clonal propagation on a large scale is still pretty costly, but if the economics worked out, it could be pretty exciting. The ability to select elite individuals rather than populations could dramatically speed up breeding progress.
ReplyDeleteYeah, that's an interesting point. There's been a lot of interest in controlling apomixis for the same reason (picture ramping up hybrid seed for commercial sales without having to waste ~ 1/5th of your field on unharvested males). To some extent elite individuals can already be selected with di-haploids, but you lose half their alleles...
ReplyDeleteIt would be interesting to see how pests and diseases of extant grain crops adapted to perennial versions - particularly fungi with overwintering spores that might survive in the surface debris. Are they envisaging a mix of clonal cultivars in a field, like an orchard?
ReplyDeleteI'm not sure, but at their website it's made clear that dealing with pests and pathogens is one of their primary concerns.
ReplyDeleteI suspect more than anything perennial crops just don't fit into the business model of the larger seed companies. They are probably so focused on selling seeds every year together with the chemicals.
ReplyDeleteI think it's one of the problems people campaigning for major changes in the worlds food system have, is just the inertia large seed companies have, and how set they are in their ways. Why fix something that isn't broke?
Yeah, i think that makes a lot of sense. It's a great example of why we need government supported and non-profit research. There are lots of great ideas that just won't be profitable anytime soon (if ever).
ReplyDeleteI agree completely!
ReplyDeleteI would think diseases would be the biggest reason not to perrenialize grains. As it is, cultivating wheat two-three years in a row on the same land increases diseases considerably, which is part of the reason for crop rotation (the other part being to get a chance to put some legumes in).
ReplyDeleteSeems like there's a huge disease and pest-resistance problem to be sorted out before perrenializing grains could be economically feasible.
While perennial crops might be a good idea, i don't think they would be as great as everyone envisions they would be. I suspect there would be a tradeoff somewhere. In the case of a perennial corn, the plant would probably spend more time (at least in the first year) establishing a deep root system and thick foliage, and probably would only produce seed every few years. I doubt it would produce seed every year. I've grown Zea Diploperennis, and i must say it has a very different growth habit than that of corn. It has a very remarkable root system though. i don't know, just a thought.
ReplyDeleteYeah I think you'd need to expect a 1-2 year establishing period for most perennial crops. In addition to yield, we'd also run into the problem of so many farmers renting their land on a year to year basis.
ReplyDelete