Category: Nutrition

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Transhumance in central Italy

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Another interesting thing about the Gran Sasso (pictured above in a photo I took a few days ago) that is related to agricultural biodiversity, apart from the famous lentil I talked about earlier 1, is that its grazing lands are at one end of a famous transhumance route.

Transhumance is the seasonal movement of livestock in search of pasture. The route in question, the Royal Shepherd’s Track, has been proposed as a World Heritage Site. Its other end is at Capitanata, near Foggia, almost 300 km away to the southeast.

The Track may have been in use for a thousand years, but until recently the future of this way of life in Europe was bleak:

…though transhumance seemed doomed a few decades ago, all of a sudden — thanks to the commitment of a number of dedicated players as well as support from people in high places (the EU, Slow Food) — it looks like it’s due for a reprieve…

A key player in the transhumance revival is Roberto Rubino of Anfosc, 2 an Italian organisation devoted to quality cheeses made from the milk of animals that live outdoors (‘sotto il cielo’) in ancient pastures rich with hundreds of different grasses, wild flowers and herbs instead of being shut up in stables and pumped with artificial food…

Patrick Fabre of the Maison de la Transhumance in St Martin de Crau, Provence, is singing from the same hymn sheet. Like Rubino, he notes that animals fed naturally and grazing out in the open are healthier, while the meat (and/or cheese) they produce is of superior quality and distinctive flavour. Some of these regional products (Sisteron lamb, fromage d’alpage) enjoy Label Rouge and/or Protected Geographical Indication (PGI) status, and command a corresponding premium.

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Vitamin C mystery solved, again

I blogged three months ago now about what was touted at the time as the final elucidation of the metabolic pathway by which plants make vitamin C. The piece in EurekAlert! which I quoted says:

UCLA and Dartmouth scientists have identified a crucial enzyme in plant vitamin C synthesis, which could lead to enhanced crops. The discovery now makes clear the entire 10-step process by which plants convert glucose into vitamin C, an important antioxidant in nature… It was not until 1998 that a biosynthetic pathway was proposed to explain how plants make this compound. Research confirmed much of the pathway, although one crucial missing link continued to baffle scientists and remained unknown until this new research.

So imagine my surprise when I read this today in FreshPlaza:

Agricultural scientists say they have uncovered the last big secret of vitamin C in plants, and it will create the chance to naturally breed healthier fruits. The breakthrough in understanding just how plants manufacture vitamin C will enable state science company Hortresearch to identify DNA markers for individual plants naturally producing high levels of the vitamin… Hortresearch’s science general manager, Dr Bruce Campbell said the team had isolated the last undiscovered enzyme and proved it controlled vitamin C in plants. The enzyme was the last step in a chain of research begun overseas nearly 80 years ago by scientist seeking to understand how plants produce vitamin C.

The research comes from New Zealand rather than the US, and was carried out on wild and cultivated kiwi fruit species with contrasting levels of vitamin C, rather than on Arabidopsis, but otherwise sounds as if it was aimed at solving pretty much the same problem. No way to tell from these brief summaries of the two pieces of work whether they came up with the same answer, though. That will take some more digging.

Anyway, it does seem likely that gene-jockeys will be falling over themselves all too soon trying to engineer a higher vitamin C apple, marula or whatever. Good luck to them. I’m no Luddite. But our friend Ola does have a point in his comment on my recent post on potatoes. Would it not maybe be easier and more cost effective to try to get people to eat foods which are naturally high in vitamin C?

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Screening potatoes for micronutrients

Yet more about iron (and other assorted micronutrients). A recent post of mine elicited a comment from Glenn to the effect that breeders have screened germplasm collections of the major staples for micronutrient composition. I was skeptical about the extent to which this has been done (though not, I must add, about the fact that there will be much more of it in the future). Another post, this one by Jeremy, suggested that there was precious little information out there about variety-level nutritional information.

Well, I’ve now come across a paper that allows us to put some numbers on the amount of screening that has been done for one staple crop, the potato. There’s only an abstract freely available online, but a paper by CIP scientists reports (among other things) on micronutrient levels in native potato varieties in Peru:

Several studies have reported mineral concentrations in improved potatoes… However, limited information was available about the mineral concentration of potato germplasm and breeding materials until 2006. A detailed study was undertaken to determine the levels of Fe and Zn in 37 native varieties, both grown by farmers as well as from the collection under custody at CIP.

The potatoes were grown in a couple of different places. There was lots of variation, both genetic and due to the environment where they were grown, and also an interaction between these factors. And the heritability was high, suggesting that there is potential for improvement through selection and breeding.

But let’s remember that the total CIP potato collection amounts to over 7,500 accessions. That means that some 0.5% has been screened. A good start, but still only a start.