Conversation so far:
Who was Norman Borlaug's most vocal critic?
Throughout his years of research, Borlaug's programs often faced opposition by people who consider genetic crossbreeding to be unnatural or to have negative effects.
What was critic's biggest issue with Norman Borlaug?
Borlaug's work has been criticized for bringing large-scale monoculture, input-intensive farming techniques to countries that had previously relied on subsistence farming.
Did Borlaug prove his critics wrong?
What did Borlaug think about his critics?
Norman Borlaug refuted or dismissed most claims of his critics, but did take certain concerns seriously.

Question: Which concerns did he take seriously?
Self-contained rewrite: Which critic concerns did Norman Borlaug take seriously?