Biotechnology is crucial to the growth of food productivity and security

8 comments

1. Arg. Things like this make me crazy:

   According to a position statement from the Union of Concerned Scientists, GM foods may pose harm to human health or the environment. The organization calls for thorough risk assessment before introductions of all biotechnology products. Others cite the lack of long-term data on these and other possible impacts.

   “may”? Can we elaborate a teensy bit more, please? I can say anything “may” cause harm without providing any evidence. And we already have through risk assessment! It could be better, and more science based, but then Union of Concerned Schmucks should be calling for better risk assessment not implying that it doesn’t exist. Then the lack of data, long term or otherwise? Please. We have more data on genetic engineering than we do on practically anything else.
   Also, notice how Scientific American hides the science on the 2nd page of the article. They’re all “look there’s a controversy” and I bet most readers don’t even bother going to the next page to learn about the awesome developments like C4 crops and RNAi.

2. “Scientific” American.
   Scientific my ass.

   There are three types of photosynthesis, two of which are known as C3 and C4. Most plants rely on the C3 process, which uses carbon dioxide and fixes three-carbon compounds in a photosynthetic cycle, but a few have evolved the more efficient C4 variety, developing a competitive edge by fixing four carbons per cycle.

   No. Wrong. C4 does not fix 4 carbons per ‘cycle’ compared to 3. C4 avoids wasteful photorespiration by concentrating CO2 around RuBisCO rather than fixing CO2 directly – one carbon is fixed per cycle (although it is fixed twice in a C4 plant – a 3 C molecule (PEP) is carboxylated in the mesophyll to produce a 4 C molecule (malate) which is then transported to the bundle sheath where it is decarboxylated to form pyruvate + CO2 – the pyruvate (3C) then shunts back to the mesophyll where it is phosphorylated back to PEP to complete the cycle.
   Energetically more expensive but no wasteful (or less) photorespiration therefore better under certain conditions (CO2 concentration, O2 concentration and temperature are the main drivers – if I remember right the evolution of C4 grasses occured after a rather large drop in CO2 levels pushing the advantage from c3 to c4 – increasing CO2 levels will level the playing field (whether or not parity will be reached or C3 will retake the advantage I don’t know – if so all efforts to C4ify C3 plants will be in vain – although we’ll have a lot more to worry about than a bit of wasted effort)

   The feat of introducing nitrogen fixation into corn and sorghum—or other genes that allow a crop to require less nitrogen—alone would cut costs and pollution markedly as well as drive higher yields.

   N fixation and NUE genes shouldn’t really be dealt with in the same paragrph like this – they’re totally different things which both just happen to involve nitrogen – there are various approaches to N fixation (either you make the plant do it, which afaik would be a one up on nature as any plant fixation is actually sybiotic rather than done in planta, or you engineer/discover bacteria which will fix N for your plant of choice) which do not overlap with NUE in any way (and there isn’t really reason to believe you’d drive higher yields with either approach – it’d be cool if you did (and by definition any increase in yield at agronomic levels of N application is an increase in NUE) but one of the goals of my team is to get plants to produce the same with less (ie 30-60lbs less N per acre) – whereas N fixation would be looking to do somewhat more than this – but it costs more energy to fix N than to take it up (although not hugely more) so one would expect this to reduce N applied and possibly yield also, but for the economics of reduced N application to more than make up for the drop in yield.
   The comments section is also a depressing read – I wasn’t aware that Monsanto produced fertilizer, or that we relied on chemical sales from our seeds (we, I think, now make more off seed sales than chemicals as Roundup tanked horribly over the last couple of years whereas traits and seeds made gains)

3. Oh as an aside – are they sourcing from Pollan? He makes the same claims about the differences between C3 and C4 plants – I have to wonder if Scientific American also thinks that maybe, just maybe, fungi utilize lunar energy rather than solar.
   (I guess in a country where Palin is considered a potential presidential candidate the definition of “scientific” can be pretty fuzzy)
   /rant

4. omg I didn’t even notice those errors I was so worked up by the crappyness on the 1st page. Unfortunately, both SA and Discover aren’t what they used to be.

5. Meh its a hot button issue for me… first ridiculously hard thing I had to do at Monsanto rather than being work related was a journal club presentation on a proteomics paper about C4 metabolism – it is vastly fascinating and I hate to see the process not just glossed over but made up because C3 and C4 seem to suggest different things (whereas if I remember right it just refers to the number of C atoms in the molecule created by fixation of CO2 – which is oxaloacetate (which then is processed to malate generally (so I’m not above being somewhat erroneous myself)) in the case of C4 and 3-phosphoglycerate in the case of C3)

6. Another idea is to bioengineer major crops to fix nitrogen… The feat of introducing nitrogen fixation into corn and sorghum—or other genes that allow a crop to require less nitrogen—alone would cut costs and pollution markedly as well as drive higher yields.

   It is a pity that the writer gives the impression here that simple introduction of nitrogen fixation is a realistic goal. IMHO it’s a dead end. He’s missed the opportunity to highlight ways in which nitrogen use efficiency is being explored, but I guess it would involve more explanation and in depth understanding of how it can be practically useful and its a bit more involved than magically adding nitrogen fixation to plant. But I guess it’s good journalism to paint a picture of magic bullets that can solve big problems and Scientific American want to keep it simple. I’m a bit surprised to see the C4 blunder though. Arggh!

7. More thorough risk assessment needed?
   There’s $100,000,000 and more spent. And still the nay-sayers say “not much has been done, its all Monsanto money” and other untrue blather.
   See this new post
   15 years, 81 projects, 400 teams and €70 million all about GMOs and GMO safety– thank you European Union taxpayers
   Syndicated from GMO Pundit just now.

8. It is a pity that the writer gives the impression here that simple introduction of nitrogen fixation is a realistic goal.

   I wouldn’t call it impossible, just low probability of success with high payoff – definitely a blue sky project and not something anyone should rely on turning up in the next couple of decades though.

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