agriculture Feeding the world Link Posts

BBC on drought tolerant maize/corn

There’s a new episode of BBC’s Discovery: Feeling the World out this morning. It’s only 26 minutes long, and the full piece is definitely worth a listen, but if you don’t have 26 minutes, the meat of the post can be summarized in 8 minutes:

3:20-7:54: Introducing the subject, developing drought tolerant varieties of maize in Africa, and the fact that the researchers working on it as using conventional breeding, marker assisted breeding and a genetically engineered trait Monsanto. When battling starvation, you use any tool that comes to hand.

18:40-21:20: This part is almost hard to listen to. You can hear the raw emotion in the researcher’s voice as the reporter keeps trying to make genetic engineering sound, at best, like a last resort. Couldn’t they just try irrigating more crop land she suggests?

25:10-end. Conclusion. I also thought this part was very powerful.

A few complaints:

Feeding the world food Plant breeding

The Color of Corn and Cultural Values

MAT_kinase has sparked an interesting discussion about the associations people have with corn of different colors. I’d previously heard that yellow corn (where pre-vitamin A carotenoids are produced in the kernels) isn’t popular in Africa, with the reason usually being given as its association with American food aid.* If yellow corn comes predominantely from food aid, it eventually becomes associated with being poor and/or starving, so that when people have a choice they eat other varieties of corn. I can’t find where I read it, but I vividly remember reading an interview with a woman who talked about the shame of eating yellow food-aid corn, knowing that it had originally been intended to feed livestock in the US, not people.

MAT points out another more pragmatic reason yellow corn may not be favored in Africa that I hadn’t heard of before. Apparently the extra carotenoids make yellow corn more susceptiable to spoilage than white corn varieties, a very pertenent issue in areas without access to the kinds of storage facilities we take for granted in American agriculture.

Jeremy at the Agricultural Biodiversity Weblog picked up the torch, highlighting a number of their own previous posts relevant to the discussion, including one by fellow blogger Luigi that relates the reaction of his own wife, originally from Kenya, on ordering polenta** at a restuarant and receiving a yellow dish.

Fortunately breeds of corn that contain even more beta carotene (the carotenoid most easily converted into vitamin A by our bodies) aren’t even yellow all the time. Although I wasn’t able to find a freely available picture, sometimes they’re ORANGE.*** While it turns out the correlation between color and beta carotene content isn’t perfect****, there’s still reason to hope varieties bred for the highest pre-vitamin A content will end up a striking orange color. For a visual examples of how orange corn can get, check out check out Dr. Rocheford’s lab website.

Will the distinction between orange and yellow***** be enough to get over the Africa’s lack of enthusiasm for yellow corn? Will the benefits of a diet with more vitamin A be enough to outweight the issues with yellow corn going “off” if stored improperly? I certainly hope the answers to both these questions are yes, but we won’t know for sure until we try. And there are some hopeful signs. For example this segment in a story from NPR:

biology Crop Profiles Genetics Plants

Banana Biology

When I was giving my lecture to on phylogeny and tetraploidies, I found out not everyone knows why bananas don’t have seeds.

The reason the bananas we eat don’t have seeds is that they are all sterile. A long time ago the Cavendish bananas first came into being when a tetraploid banana (that is a plant that has four copies of every chromosome instead of the normal two) mated with a normal diploid banana. The result, a banana with three copies of every chromosome couldn’t mate or produce seeds. One of the steps in making reproductive cells (the analog of human sperm and egg cells) is the even dividing of a plant’s chromosomes into two reproductive cells.* Normal diploid cells can easily divide into two cells (one copy of each chromosome in each cell), tetraploid plants can divide the same way (two copies of each chromosome in each cell). Hexaploid, three copies in each and so on. Odd numbers of chromosomes don’t work. The plants can’t successfully make the cells it needs to reproduce, if it can’t reproduce it can’t make seeds, and that is why bananas (or seedless watermelons) don’t have seeds.

agriculture Link Posts

Bill Gates at the World Food Prize

If you have a few minutes, take the time to either watch or read the speech Bill Gates delivered at the World Food Prize in Des Moines. While I don’t care for the operating system that made him a multi-multi-billionaire, I don’t think anyone can argue that he is doing more good with his wealth than any other member of the superwealthy.

Africa is the only place where per capita cereal yields have been flat over the last 25 years. The average farmer in sub-Saharan Africa gets just over half a ton of cereal per acre. An Indian farmer gets twice that; a Chinese farmer, four times that; an American farmer; five times that.