In the blog Applied Mythology you can find an interesting discussion on the complex issue of increased pesticide use and biotechnology adoption. I concur with the author S.D. Savage (to view his blog article please click here) in that one needs to really analyze the issue in greater detail than what has been done in some studies out there. In the special edition of AgBioForum, an article by Zambrano and colleagues hightlights some of these issues for the specific case of Bolivia and HT soybeans. You can find the article in the special issue of AgBioForum here
Mr. Savage conclusions at the end of the article are quite compelling. I reproduce them here textually.
To reiterate, pesticide use or its increase are not automatically undesirable things. It depends on what is the alternative and what is the nature of the particular pesticide in question. Plant biotechnology is just one important tool in the bigger tool box of agriculture. Sometimes it allows farmers to use a more attractive pesticide option (Bt Sweet Corn would the be best example of this). Sometimes it helps them with the adoption of sustainable practices that depend on relatively low risk herbicides. For farmers, biotechnology and pesticides are not an either/or. They are often partners.