Agricultural Biodiversity Weblog
Agrobiodiversity is crops, livestock, foodways, microbes, pollinators, wild relatives …
Jacob answers Luigi’s question about a contrast that doesn’t appear to be one thusly:
The contrast is:
Variation for seed dormancy controlled by one QTL in one population and two QTLs in the other (of which one is different from the first population).versus
Variation for flowering time controlled by the same QTL in both populations.
One does rather wish the authors or editor would pipe up too.
The Crawford Fund in Australia supports a lot of good work on agricultural biodiversity and more sustainable agriculture, but its website is a bugger. No RSS feed. And sometimes no way to link to an interesting story. Or at least, none that I can see. Nothing for it but a spot of copy and paste.
There has been a renewed focus on food security in the media of late with a range of national and metropolitan papers focusing on the topic. And the most recent AusAID “Focus” magazine is themed on food and food security, with an article by The Crawford Fund focusing on the rewards of research. Following a Crawford Fund ‘seeing is believing’ visit to Vietnam, ABC TV Landline producer Kerry Straight has been working on a special feature for the program on food security, which Crawford Fund, ACIAR and CSIRO has been assisting with through this year. The feature has now gone to air focusing on a broad range of issues related to food security from both the developing country and Australian perspectives. The feature includes a range of speakers who were part of the Crawford Fund’s State Parliamentary Conference in Brisbane in April this year. In late June, the 35min feature went to air on Landline on “The Future of Food” including Kanayo Nwanze, Julian Cribb, Rick Roush, Michael D’Occhio, Peter Carberry and others. The story can be found here. The feature provides a good overview of the complexity of the food security issue, stressing the importance of R&D. Visits to East Africa and to Aceh are currently being supported as the next Crawford Fund ‘seeing is believing’ visits.
I love the idea of “seeing is believing” tours.
Oh, pesky scientists! A bunch of them in Spain has taken a close look at one of the darlings of European tomato culture and found it, how shall we say, disappointing. ((Joan Casals, Laura Pascual, Joaquín Cañizares, Jaime Cebolla-Cornejo, Francesc Casañas, & Fernando Nuez (2011). The risks of success in quality vegetable markets: Possible genetic erosion in Marmande tomatoes (Solanum lycopersicum L.) and consumer dissatisfaction Scientia Horticulturae DOI: 10.1016/j.scienta.2011.06.013)) The subject of their investigation was a type of tomato known as Marmande, associated with the town of that name. There are several landraces of Marmande tomatoes, and in northeast Spain two of them, Montserrat and Pera Girona, are grown in adjacent areas. Each has its favoured consumers, who argue that their Marmande is better than the others’, although both Montserrat and Pera Girona are apparently facing competition in their respective niches from upstart Marmande tomatoes from France, Italy and elsewhere in Spain.
The researchers note that:
Often without experimental confirmation, many consumers consider that everything “traditional” tastes better than improved varieties.
And they’re not going to stand for that. So, they went to growers and got samples of the two kinds of Marmande, a couple of controls from further afield, and some commercial varieties, grew them in the field and evaluated the hell out of them, including a slew of molecular tests. And here’s the bad news; while the controls and far-off Marmandes were quite distinct from one another and from Montserrat and Pera Girona on molecular data, those two could not be separated from one another, favoured consumers be damned. There were differences in the outward look of Montserrat and Pera Girona, but within each landrace the range of scores on sensory traits (what consumers are probably “preferring”) was far greater than any differences between the two.
There are differences, of course, mostly in what the two varieties look like. Montserrat has flattened fruit, while Pera Girona is pear-shaped. So, what’s going on? Farmers are clearly selecting to conform to the landrace stereotype, but not much else.
[T]he recent evolution of these tomato landraces has resulted in uniform fruit morphology and wide variation in texture, aroma, and taste. It seems farmers have selected seeds solely on the basis of fruit morphology, neglecting sensory traits. Texture, aroma, and taste do not correlate with the shape of the fruit; thus, the persistence of separate markets for these varieties is exclusively due to morphological differences in the fruit. It seems that consumers continue to identify certain morphologies with superior quality.
And this is by no means a unique phenomenon.
Selection for morphological traits while neglecting sensory traits seems to be practiced widely: variability in sensory attributes related to a genetic base has been reported in beans … and in eggplant. … In other cases, variability in sensory traits is related to cultivation practices, as in the RAF tomato, which can be acid, sweet, and crisp when cultivated in salty soils but of poor sensory value when cultivated in high yielding soils. As a result of cultivation expansion, the prestige of RAF tomatoes blossomed and wilted in a short time.
Inevitably, then, consumers are going to be disappointed by their chosen landrace at least some of the time. What’s to be done?
In order to consolidate the market, the link between organoleptic and morphological traits must be maintained and reinforced.
In other words, get back to basics: gather a group of keen consumers, identify what it is about each variety that attracts them, and then start selection to make sure that the tomatoes deliver more than appearance. As good as their word, the scientists have already done this for Pera Girona, and they say that just one round of selection has already “resulted in an improved inbred line”.
Ah, but is it still a traditional landrace?
The abstract of a new paper in PNAS is fascinating. The paper is called Risk of collective failure provides an escape from the tragedy of the commons, and what it seems to be saying is that a small group, which will pay dearly for failure, is more likely to manage a commons successfully. This seems deeply obvious. Garrett Hardin himself said that one of his biggest tragedies was the failure to call his ground-breaking 1968 Science paper The Tragedy of the Mismanaged Commons, for there is nothing inherently tragic in the idea of a commons. ((This video, one of several available now, is eerily prescient.)) Exclusive community rights, and shame, he reckoned, were usually enough to keep a commons sustainable. So I’m probably missing the point, and I currently don’t have access to the full paper to find out what Santos & Pacheco, authors of the paper, are saying in full. Take this bit from the abstract, for example:
We also offer insights on the scale at which public goods problems of cooperation are best solved. Instead of large-scale endeavors involving most of the population, which as we argue, may be counterproductive to achieve cooperation, the joint combination of local agreements within groups that are small compared with the population at risk is prone to significantly raise the probability of success.
Does this mean that we should leave it to politicians or professional negotiators to hammer out global agreements? Surely not as long as they require our approval, or (financial) support. And how might the conclusions of Santos & Pacheco apply to, say, negotiating access to the global “commons” of genetic resources? Answers on a postcard please.