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Induced mutations? Nein danke.

We briefly nibbled SciDev.Net’s take on a press release from the International Atomic Energy Authority, advocating “Nuclear Science for Food Security”. It’s an old story; bombard seeds with radioactivity to induce more mutations, from which breeders can select wonderful new varieties. But as a correspondent reminds us:

There’s really nothing inherently wrong with it. Because it’s a totally random, “shotgun” approach to generating new variations, it lacks the benefits of natural selection to sort out not only what’s viable, but also what’s somehow well-adapted to growing in the environment and have other desirable traits.

Radio-induced mutagenesis was a popular technique decades ago, and some improved varieties were produced as a result. But I think that a much more logical approach would be to more fully assess and exploit the vast amount of extant diversity currently languishing unstudied in genebanks and farmers’ field, material that has already passed through the filter of many centuries, if not millennia, of natural and human selection. Radio-induced mutation is really just a shot in the dark. Better to focus more attention on the existing crop diversity that has yet to be exhaustively collected, characterized or evaluated, before resorting to such an aleatory approach.

Do you agree? Is inducing extra mutations — by chemistry, radioactivity, whatever — a good way to generate more diversity for breeders (and farmers?) to select from. Or should we focus on understanding the diversity we already have? It isn’t binary, of course, but I wonder where the balance should be?

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Go forth and grow halophytes

That seems to be the plea Jelte Rozema and Timothy Flowers make in a Science paper that’s just out. ((It’s behind a paywall, but you can read other people’s take on it at Mongabay and Wired.)) But, frankly, I found the paper disappointing, not least because it is short on clear recommendations. For example, what is one to make of this?

Because salt resistance has already evolved in halophytes, domestication of these plants is an approach that should be considered. However, as occurred with traditional crops such as rice, wheat, corn, and potatoes, domestication of wild halophytic plant species is needed to convert them into viable crops with high yields. Such a process can begin by screening collections for the most productive genotypes.

Are they telling us that domestication of new species is a more profitable approach than trying to breed salinity-tolerance into existing crops? I think so, in which case it would be an interesting view, but I’m not altogether sure that’s in fact the point they’re making. It could have been better phrased. I mean those first two sentences could be summarized as

Domestication of halophytes should be considered. However, domestication of wild halophytes is needed.

Not sure how the editors at Science let that one by. There was also no explicit reference in the paper to the International Centre for Biosaline Agriculture and its genebank. Or to the possible role of crop wild relatives in breeding for salinity tolerance. All around, an opportunity missed.

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Great Expectations

Nature has a (behind paywall) feature on Five crop researchers who could change the world. Rather than celebrating those who have arrived, Emma Marris highlights the work of five researchers who still have some way to go before reaching the Food Hall of Fame.

These are her picks.

Peter Dodds (CSIRO, Australia) works on the fundamentals of wheat stem rust. He investigates the substances that the rust fungus excretes, and the plant could use to trigger a defense reaction. He hopes to engineer new and more complex resistance, that the rust might not be able to break. Seems particularly relevant in the light of the UG99 scare.

Jerry Glover is a crop perennializer at the Land Institute, in Kansas, USA. The folks at the Land Institute want us to move from annual to perennial crops. That would be better for the soil and would take much less energy (nitrogen) to produce. They are clearly in it for the long run, but here’s a short and palatable piece about it.

Zhang Jinghua (Hong Kong Baptist University) works on deficit irrigation. The theory is that under modest water stress plants shift all their resources to reproduction and hence grain yield can increase. One trick in his book, and that of Australian grape growers, is ‘partial root zone drying’. Some roots are dry, and signal the need to fill the seeds, while other roots can access the water that is needed to keep producing. Water saving is particularly important in increasingly water scarce Northern China.

Richard Sayre, the director of the Institute for Renewable Fuels, Missouri, USA, was selected because he heads the BioCassava Plus collaboration. They are hoping to develop genetically modified cassava of which 500 g contains the daily requirements of protein, vitamin A and E, iron and zinc ((What will be left to do? Fluorescence to lighten up the nights, and the ability to use the root as cell phone battery?)). They have succeeded in transformations for individual traits, now they have to figure out how to artificially transfer 15 genes into a single variety.

Julian Hibberd (U. of Cambridge) studies photosynthesis. He is one of the brains in the C4 rice consortium led by IRRI. They are trying to create rice plants with C4 rather than C3 photosynthesis. C4 photosynthesis is more efficient at high temperature, and it could be the next big thing (after short straw) to radically elevate rice yield potential — “by a whopping 50%” ((Will they also re-engineer the straw so that it can carry all that grain?)), thinks Hibberd. Seems far fetched, but C4-ness has independently evolved in many plant families, so why not another time, with a little help?

An interesting group, but did Nature miss anyone? Perhaps in branches of research less dominated by biotech? Let us know.

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New NUS “entity” launched

Crops for the Future, a new international organisation dedicated to the promotion of neglected and underutilized species, was launched a few days ago.

Crops for the Future has evolved from a union of the International Centre for Underutilised Crops (ICUC) and the Global Facilitation Unit for Underutilized Species (GFU). It will be hosted in Malaysia by Bioversity International in a joint venture with the University of Nottingham, Malaysia Campus.

Best wishes to all concerned!