Cereal varieties screened for nutritional benefit

You may remember the obsession we developed here last summer about diversity among crop varieties in nutritional composition in general and glycemic index in particular:

Good measurements of characteristics such as GI for specific, named and recognizable varieties, whether the products of modern breeding or traditional farmer varieties, would be really valuable for lots of reasons, not least to add substance to claims that diversity of diet in and of itself is good for one.

Well, our prayers are being answered. Foodnavigator has a news item about the “Healthgrain diversity screen.” Researchers

grew, harvested and milled 150 wheat varieties used for bread making and 50 other grain varieties — oats, barley and rye — over a one-year period in Hungary. The grains originated worldwide…

They then measured “the components known to play a role in prevention of cardiovascular disease and type-2 diabetes,” including tocols, sterols, phenolic acids, folates, alkylresorcinols and fiber components.

Only one site and one year, and 150 are not that many compared to the tens of thousands of wheat landraces and varieties in the world’s genebanks, but you have to start somewhere, and “the Healthgrain diversity screen has generated the most extensive database currently available on bioactive components in wheat and other smallgrain cereals.” Should be a great breeding resource.

Truth or consequences?

According to John Ioannidis, most published research findings are false ((Ioannidis is likely of Greek extraction, perhaps even of Cretan blood?)). This is because of the Winner’s Curse: scientists need to oversell to get heard, published and funded ((Young, Ioannidis & Al-Ubaydli in PLoS Medicine; and discussed in The Economist.)).

Does this affect agrobiodiversity research?

Yes, it does.

Take this press release that came in today: “Research finds way to double rice crops in drought-stricken areas.” Right. Perhaps there were some extreme experimental conditions where this is true, but I find it hard to believe there is a magic set of markers that will let you select for double rice yield under normal drought conditions relevant for farmers. I think that’s a bit much. Perhaps the typical benefit might be as high as 10%, but that does not make for a good headline (even though it would be a staggering result, really) ((The paper’s abstract speaks of an effect of 40% in the extreme case, that’s more reasonable. I wonder if 40% means doubling to the person who wrote the press release )) .

If only, then we could also throw in the Hardy gene, for another 50% boost.

Here’s another example of overselling, say Stuart Orr and colleagues ((Stuart Orr, James Sumberg, Olaf Erenstein & Andreas Oswald. 2008. Funding international agricultural research and the need to be noticed. A case study of NERICA rice. Outlook on Agriculture 37:159-168.)) in a recent review article on NERICA — “New Rice for Africa”.

NERICA is a group of rice varieties produced at the Africa Rice Center (WARDA). They have been produced after a breakthrough in rice genetics, the use of embryo rescue to cross Asian (Oryza sativa) with West African (O. glaberrima) rice. The offspring of these crosses has been back-crossed a number of times with sativa parents such as IR64.

NERICA varieties have been referred to as “miracle rice” and are said to be higher yielding, have higher quality, compete better with weeds, be more stress resistant, etc. etc. etc. This has created a lot of interest, enthusiasm and funding for their continued development and dissemination. Orr says that all the hoopla about NERICA is not backed up by the (published) facts. This perhaps explains why adoption of NERICA varieties is not what was hoped for.

Wopereis and colleagues ((MCS Wopereis, A Diagne, J Rodenburg, M Sié & EA Somado. 2008. Why NERICA is a successful innovation for African farmers. A response to Orr et al. from the Africa Rice Center. Outlook on Agriculture 37:169-176.)) defend WARDA and NERICA saying that NERICAs perform well, that there are new published data, that the outlandish claims were made by others, and that there is nothing wrong with enthusiasm.

I do not know how good NERICAs are, but some farmers like them, which is good. And WARDA definitely has created a renewed interest in breeding rice varieties for Africa, where many, it seems, had given up. That’s good too. Better still would be to move beyond the NERICA brand, and try and disseminate a broad and diverse set of varieties. Let the farmers decide.

Mine’s a decaff

We’re always on the look-out for examples of the financial value of germplasm collections which don’t involve some obscure and faraway disease, however nasty. So it was really nice to come across a great story about the search for naturally low-caffeine coffee, and in the Wall Street Journal no less. Coincidentally, there was also a blog post yesterday about the wild coffees of Madagascar. ((Yes, dear reader, we nibbled both these things yesterday, but I thought, on reflection, that they were worth a bit more than that.)) Some of the many species found on that island are known to have low caffeine levels, but “[a]ttempts to transfer the caffeine-free property from wild coffee species of Madagascar, which produce an inferior beverage, to C. arabica have failed owing to a strong genetic barrier.”

LATER: I wonder if the recent Korean “land-grab” in Madagascar will have an effect on wild coffees and other interesting endemics.