Sunday, 5 December 2010
Wild rice is both rice and grass
“Wild rice is not rice, but a grass” said a commentator on the (original) Iron Chef, on SBS TV. This is both right and wrong.
Keen followers of my botanical ramblings will remember I wrote about this some time back in an issue of the Friends of the Gardens' magazine The Gardens, and also spoke about it on air. To celebrate the Australianisation of Iron Chef (to which I haven't quite connected) I repeat here my brief investigation into the origins of rice, wheat and corn.
Rice, wheat and corn are all seeds extracted from a member of the grass family Poaceae. So technically they are a kind of grass.
Rice was first grown in agriculture some 7000 years ago, in China. Since then it has been continually selected and propagated to produce the high yielding crops in cultivation today.
Common rice, eaten by at least three billion people every day, is a cultivar of Oryza from Asia or Africa.
Wild rice is not an ancestor of common rice, but comes from the closely related Zizania, a mostly North American genus. Like common rice it grows best in wet areas. A species of Zizania from China, called Manchurian Rice, is now rare in its natural habitat. It grows well in cultivation – in fact so well that (like many other plants and animals) it has become an invasive species in New Zealand.
So wild rice is a bit different to regular rice, and both rices are grasses…
Wheat has a complex origin. It was bred from a mix of cultivated Triticum and weedy Agropyron species growing in Mesopotamia over 8000 years ago.
Corn (or maize) comes from Zea mays, bred from species that grew naturally in Mexico. Domestication of corn also began 7-8000 years ago.
We don’t have rice or wheat growing in our Gardens, but we do have commercial corn in our Cadi Jam Ora/First Encounters garden.
We also have one of Corn’s purported ancestors, the high altitude corn Zea mexicana, in the Rare and Threatened Garden in Sydney's Royal Botanic Gardens. Teosinte as it is commonly called, has small ‘ears’ with only a handful of kernels, each protected by a tough outer shell reminiscent of the closely related Job’s Tears (Coix lacryma-jobi). Thousands of years of breeding removed the outer shell, and pumped up the volume of the grain.
Image: The original corn with its small ‘ears’, and kernels encased with hard shell, growing and fruting in Sydney's Royal Botanic Gardens. *This is based on a story from the Radio Archives (June 2007).