Genetic Maize

One topic of this blog is the graduate student experience, with the aim of passing on a little advice to prospective graduate students. The lesson for today is: stand up for yourself. 
Today was the Seventh Annual Norman Borlaug Lectureship Poster Competition For Graduate and Undergraduate Students. I was very excited about the competition this year, because my research is very important to world food issues. The poster is: Characterizing seed storage proteins in teosinte and tripsicum, with the objective statement “To find unique seed storage proteins in relatives of maize that might be used to improve maize nutritional qualities.” I like to imagine that Norm Borlaug would approve. I purposefully chose a table at the opening of the room, just as I did last year, so I would be easily noticeable. I even brought samples of the seed so people could see for themselves how different teosinte and tripsicum are from maize, because everyone likes hand-on science. I thought I did all the right things to make a good showing, even if my poster wasn’t the best. Unfortunately, the judging was less than smooth.
(more…)

In Reducing the environmental impact of farming, I talked about Nathan Pelliter’s work on Agricultural Life Cycle Analysis as a way to evaluate which farming methods have the least environmental impact. While the ideas apply to any type of farming (or really to the production of anything), his main work is actually on animal agriculture.
The return on investment of most types of animal agriculture is small compared to that of plant agriculture. For example, cattle require about 6 pounds of feed to produce 1 pound of muscle. All of the water, fertilizer, and pesticides required to grow 1 pound of plant material is thus multiplied by 6 to produce 1 pound of beef. Granted, it isn’t quite that simple, as parts of plants that aren’t used for human food can be fed to animals, but the point holds, even in organic systems. (more…)

Atmospheric concentrations of greenhouse gasses are rising, but reducing them isn’t as simple as taking cars off the road. A significant part of the problem rests is agriculture. What is it about agriculture that is such a problem and how can we develop changes that will have the most benefit?
Agricultural Life Cycle Analysis is a useful tool in collecting information and making decisions. LCAs take every input and every output into consideration including difficult to consider ouputs like greenhouse gas emissions.
Nathan Pelletier from Dalhouse Uni in Nova Scotia presented his work on ag LCAs at Iowa State recently. He explains that actually conducting LCAs can be difficult. First, we need to define the scope of the analysis. For example, if we consider milk production, we should likely include the cow herself, food, water, and waste. We probably should include all of the inputs and outputs associated with feed production and transportation. We might include the inputs and outputs of pasteurizing and transporting the milk. Also difficult is actually quantifying all of the inputs and outputs to air, soil, and water. Finally, it is difficult to complete a meaningful impact assessment including the identification of “hotspots” or most negative impacts. Despite the difficulties, LCAs are worth the effort. Nathan reminds us that agriculture produces 1/3 of global warming emissions. The demand for food will will double by 2050, so we need to half the impact to continue a constant level of damage.
(more…)

I went to a seminar titled “Harvesting ecosystem services from cellulosic biofuel landscapes” at Iowa State yesterday. The speaker was Michigan State Professor of Entomology Douglas Landis. His research is very practical, focusing on which types of plants should be used in biomass production for biofuels to encourage the highest biodiversity of insects. This is important because insects provide many ecosystem services, including pollination and predation of pests.
His work shows that switchgrass and mixed prairie encouraged higher numbers of some native insect species, but also encouraged some invasive insects. Corn likewise had mixed results (especially encouraging native insects that like to eat corn!). His methods of data collection are simply fun – low tech but effective – nets, sticky traps, leaf blowers turned into vacuums, and such.
It’s good work, because we really need people working on the sustainability issues associated with farming. Growing biomass for fuel, as any farming, could be beneficial or detrimental to the environment – it’s up to people like Dr. Landis to make sure it’s the former.
Unfortunately, Dr. Landis seems to be misinformed on one issue – Bt crops. I won’t go into too much detail here, but Bt crops have been shown to increase insect biodiversity because overall levels of pesticide are decreased. I would have thought that an entomologist concerned with biodiversity would at least contemplate a cost-benefit analysis of Bt.
In the introduction of his talk, Dr. Landis mentioned the 2007 PNAS paper “Toxins in transgenic crop byproducts may affect headwater stream ecosystems”. This paper is more than a little controversial, because the authors make broad claims that do not follow from their results. The authors make the typical mistake of lumping that is never appropriate in science. All Bt is not the same, all aquatic insects are not the same, all corn fields are not managed in the same way… Dr. Landis should have at a minimum mentioned that the paper has been contested before trotting it out as evidence.
I wrote about the press release of the paper when it first came out, and I continue to be frustrated by the mediocre science and the terrible way that people twist results to make the point they want. Feel free to read the paper for yourself, but don’t pass up the rebuttals. Beachy, et. al. make the point that papers like this are taken by the popular media and used to fuel debates – regardless of the strength of the science. It truly is the responsibility of every scientist and especially of every reviewer to put aside personal bias for or against the paper and make sure the conclusions are supported as much as possible by hard evidence. The reviewers of this paper should have sent it back, requesting some of the experiments explained in the rebuttals (such as dose-response measurements, as suggested by Parrott).

Dr. Landis showed this pair of images from the Rosi-Marshall paper, implying that corn residues in streams are all the fault of genetic engineering, as if organic corn crops or other crops in general don’t clutter up streamheads. He seems to think that harvesting switchgrass or mixed prarie would somehow not leave the same sorts of residues in streams.
Of course, all crops are going to leave residues in nearby streams, plant matter that is not a natural part of the ecosystem. What I find most ironic is that, if crop residues actually do damage streams, we should start harvesting them for biofuels right now!
To make things even worse, Dr. Landis told the audience (full of impressionable sustainable ag majors) that “the Bt toxin leaches from crop residues into streams where it kills aquatic insects.” This statement is wrong for a lot of reasons, the main one being that there is zero evidence that Bt leaches from the plants that produce it. If you know of any evidence showing that it does, please let me know, but I’m not going to hold my breath.
E. J. Rosi-Marshall, J. L. Tank, T. V. Royer, M. R. Whiles, M. Evans-White, C. Chambers, N. A. Griffiths, J. Pokelsek, M. L. Stephen (2007). Toxins in transgenic crop byproducts may affect headwater stream ecosystems Proceedings of the National Academy of Sciences, 104 (41), 16204-16208 DOI: 10.1073/pnas.0707177104

There’s been a bit of controversy lately at Iowa State on the subject of “intellectual suppression” of intelligent design. Some pent-up drama from Dr. Guillermo Gonzalez’s tenure denial is still around, and Expelled brought the beast back to life. Of course, having Dr. Hector Avalos here helps to keep things interesting. The first ISU Daily article in this round, “Avalos: ‘Expelled’ wrong on Holocaust” has accrued almost as many comments and letters to the editor as the articles about Gay Pride week. The whole subject is frustrating, because I don’t think there is a controversy. No one should dictate what religious beliefs a person can or can not have.

In this country, separation of church and state is a necessity (due to the many faiths or absence of faith present). Therefore, religion can not be taught in state funded schools. Period. If people want to study things other than approved evidence based curricula, they are welcome to do so at home. Dr. Gonzalez is also welcome to study these things, but not while he is on the payroll of a public university to study science. If he was a religious studies professor, things would have been entirely different. The NY Times reports today about Dr. Francisco Ayala, a former Dominican priest and current evolutionary biologist and geneticist at UC, Irvine. Dr. Ayala’s thoughts on the ID / Evolution controversy are amazing, unlike any I have every seen. The article is: “Roving Defender of Evolution, and of Room for God”, which I learned about from the Knight Science Journalism Tracker.

(more…)