World Net Primary Production

Area (left) and total (right) NPP. From http://www.sprl.umich.edu/ GCL/Notes-1998-Fall/energyflow.htm

Climate and NPP

NPP is strongly dependent upon climate. From http://www.sprl. umich.edu/GCL/Notes-1998-Fall/energyflow.htm

Bt Corn Pollen kills Monarch Butterflies

Transgenic corn containing Bt genes is resistant to ravenous larvae of the European corn borer and corn earworm. But a heavy dusting of its pollen on milkweed kills larvae of the Monarch.From: Transgenic Corn vs. Monarch Butterflies, Barry A. Palevitz, June 7, 1999 <<http://www.thescientist.library.upenn.edu/yr1999/june/palevitz_p1_990607.html>>

Biotech Crops: Risk and Promise

• Frankenfoods, or a boon for the world?

• Vitamin A-producing rice could benefit malnourished millions

• drought, disease and pest-resistant crops could provide the next green revolution

• but genes could “jump” from trangenic plants to wild plants, creating monster weeds

• today, a large fraction of our corn and soybeans are “roundup-resistant”, allowing wide use of herbicide (and no-till agriculture which protects waterways)

• Much bigger issue in Europe than in USA

Biotech Foods - Dilemma for Producers• Genetically-modified crops are now widely grown

– 52% of soybeans (38 m of 73 million acres)

– 25% of corn (19 m of 76 m acres)

• Foodstream can not easily separate g.m. from non-g.m. crops

• Major food producers are unsure of public’s response to genetically altered crops– McDonald’s has asked suppliers not to ship genetically-

modified potatoes, but cooks fries in vegetable oil made from g.m. corn and soybeans

(NewYork Times 4 June 2000)

Biotech Crops: Some Websites

• Www.nbiap.vt.edu

• www.ncbe.reading.ac.uk/NCBE/GMFOOD/menu.html

• www.usia.gov/topical/global/biotech