We’ve written before about assisted migration — giving plants (and animals) a helping hand to ensure that they can keep up with shifts in the areas in which they can thrive. “Managed relocation” is becoming a hot topic, which may be why the Chicago Botanic Garden is holding a one-day seminar on 11 June 2010. Details are currently sparse, but if you go, and especially if anyone says anything about crops or wild relatives, please share a report.
Diverse points of view on feeding Africa
We like to embrace different points of view here ourselves, though we also like to think there’s a certain consistency to most of what we say and do. Maybe that’s why I find it strange that a single blog, on a single day 1 can feature two such divergent posts. One — Homegrown Solutions to Alleviating Hunger and Poverty — is a thorough look at the role of indigenous fruit and vegetable crops in delivering a healthy and nutritious diet. The other — Breeding for Climate Change — links, almost without comment, to a report on the Bill & Melinda Gates Foundation’s project to deliver just two (one conventionally bred, one genetically engineered) drought-resistant maize varieties to sub Saharan Africa.
I have no doubt that genetic engineering, precision farming and other high-tech tools of modern intensive farming can supply all the calories the world will need even when it hosts 9 billion people. I do doubt that the 9 billion will actually get those calories. And I know that calories alone are not enough. People need nourishment, not merely calories.
Costs, benefits, and the search for disease resistance
An epidemic of Fusarium head blight swept through the United states between 1998 and 2000, costing the wheat industry an estimated US$ 2.7 billion. That’s right: billion.
Salvation came from Chinese and Japanese landraces, especially a Chinese wheat called Sumai 3. To prepare for the inevitable mutation of the fungus, scientists at the USDA have broadened their search for resistance. They examined 87 Asian varieties of wheat, many of them old landraces, and found good levels of resistance in 26 of them. Better yet, some of the resistance genes seem to be different from the ones derived from Sumai 3, which means that they might offer protection against different varieties of the fungus.
Just knowing that various resistance genes exist, and having markers to select more resistant crosses from breeding efforts means that future outbreaks can probably be more effectively dealt with, which is reassuring. More to the point, for our purposes, this research raises again the question: how can anyone doubt the value of genebanks? Just one disease cost just one country US$2.7 billion over three years. Genebank accessions contain the solutions. Do you really need to know the cost of every accession to decide whether genebanks are worthwhile?
Shortage of olive oil threatened
Disturbing news from The Economist:
It is becoming clear that reserves of olive oil will peak in the coming decade, as climate change wipes out most of the groves in the Mediterranean, the main production zone. The likes of Turkey will struggle to make up supply. Russia, however, expects to profit handsomely: its steppes, freed of permafrost, will soon host vast olive groves; a series of pipelines will send extra-virgin supplies westwards.
Somewhat disappointingly, The Economist seems to have taken no account of the benefits for the south of england. As we reported here earlier, home-grown olives are now on sale in the UK; can oil exports be far behind?
Restoration is germplasm use too
It is well known that plant populations do best when they grow close to where they originally came from. A myriad reciprocal transplant experiments going back decades attests to the power of local adaptation. But how close is close? The question is of very real practical importance if you’re trying to restore a habitat. By definition, the local population is gone. What is the maximum distance you should be willing to go to collect material to re-establish it?
Three hundred kilometers is the answer given in a paper just out in Ecological Applications. 2 There’s also a discussion over at Conservation Maven. The authors worked on the salt marsh grass Spartina alterniflora, which is commonly used in ecological restoration of wetlands in North America. They collected germplasm at 23 sites from Texas to Maine, genotyped them using neutral markers, and then grew them all in a “common garden” experiment in Louisiana, where they measured in various ways how well each population did. The control was a population just across a canal from the experimental site.
It turned out that clone diameter, number of stems and number of inflorescences at the experimental site, as well as genetic distance, were all significantly affected by measures of the geographic distance between the source and the experimental site. For populations up to about 300km away along the coast, performance in the common garden was similar to the control. Go further, and the source populations do not do as well where they are planted.
The authors make quite specific recommendations for restoration. Use material from at least three populations within 300km of the restoration site, and 100km if you want material that is not only maximally locally adapted but also not significantly genetically different from the original population at the restoration site.
Now, I don’t know how widely applicable these recommendations might be. I don’t know the restoration literature at all. A cursory look revealed a fairly well-developed theoretical framework, the “restoration gene pool concept.” Which has been used to develop a decision support tool.
As I say, I don’t know much about restoration. So I don’t know to what extent this sort of thing has been applied to crop wild relatives. To me, “use” of crop wild relative germplasm means use in breeding. But that is clearly very narrow thinking, and I should be ashamed of myself.