Hello David- I can´t answer your question with a specific quantitative response about reductions in seed diversity, but in general, the production of biofuels in its current model is greatly reducing overall biodiversity. This is true in any monocrop system, whether biofuels are involved or not. Most biofuel plantations are extensive, require heavy inputs of fertilizer and herbicide to maintain and do not belong to nationals of the countries in which they are located. As smallholder agriculture gives way to these extensive tracts, we can assume that the loss in seed diversity is increasing, as smallholders (campesinos, peasants, whathaveyou) are the main propagators and conservators of these resources.

Another development that is affecting seed diversity is the concentration of companies that control seed stock, now largely in the hands of giant biotech firms like Monsanto, Dow and Syngenta. See a useful digest of these issues with links to more indepth considerations here:

http://www.fewresources.org/market-concentration.html

Thanks a lot Andrea for the opinion shared and for the link. Your point is well noted and very much appreciated