An article in the latest Economist discusses the Malawi fertilizer subsidy programme. There’s been a fair amount in the media about this lately, and in particular about whether the bumper maize harvests of the past couple of years can be attributed to the extra fertilizer ((Incidentally, there’s an interesting NY Times video on what the rising cost of fertilizers means for farmers in the US.)) now finding its way onto farmers’ fields increasingly sown to modern varieties, or just to better rains. I think the jury is still out on that one, but check out this statement from the piece in The Economist:
…local seed varieties, little altered from those first brought by the Portuguese centuries ago…
I don’t know about you, but I think that rather underestimates the power of natural selection, drift and recombination. Not to mention 500 growing seasons’ worth of painstaking selection by twenty generations of African farmers.
Not to mention that maize is an obligate outbreeder.