Sunday, July 05, 2009


I'm not much of a cook, but I like messing about in the kitchen, slicing, dicing, piling one thing on another. Here in Ireland my favorite cookbook is devoted entirely to potatoes. Potato, spinach and pine nut gratin. Gratin dauphinois. Potato and courgette tortilla. Hash browns. Pan haggerty. Bubble and squeak. The Great Famine be damned, the Irish still love their potatoes. At our village shop you can get local spuds right out of the ground. Nothin' better than day-old new potatoes slathered in Kerry butter.

The problem, as noted yesterday, is that insidious pest, Phytophthora infestans.

The potato blight and the potato have long been locked in an evolutionary battle to infest and to resist infestation. Nothing conscious about this arms race -- mutation and selection, trial and error, the potato trying to stay one step ahead of the parasite, the parasite trying to keep up. The game changed significantly when biologists and chemists entered the fight on the side of the potato.

Fungicides are still the main line of defense. Selective breeding and genetic jiggering for blight-resistance are other strategies. Is the world ready for GM taters? We'll see.

Meanwhile, the fungus is not sitting idly by.

Phytophthora reproduces asexually and sexually. There are two mating types, called A1 and A2. For sexual reproduction to occur, both mating types must participate. Until recently, the A2 mating type was restricted to Mexico, the fungus' place of origin. Now A2 has spread through the United States and Europe, and landed on Irish shores. Biologists worry that the sexually-reproducing fungus will be quicker to develop resistance to fungicides, through a greater reassortment of genes. Apparently, in Mexico, where the A2 mating type is common, many new and virulent strains of blight have appeared.

It's all in the hands of the scientists. Can human intelligence outrun fungal sex? Will my neighbors keep putting firm, white, unblemished spuds on my plate? Will the Irish love affair with the potato continue to blossom? And will my darling spouse keep making her irresistible potato and leek soup, with that dollop of Irish cream and sprinkling of her very own chives?

And while you're here, does anyone have a suggestion for a nontoxic way to keep insects from eating my young spinachs, collards and lettuces?