Cassava, the primary source of nutrition for 800 million people worldwide, is receiving attention from a project seeking to boost its nutritional value.
The BioCassava Plus project, supported by US$12.1 million in funding from the Bill and Melinda Gates Foundation, involves researchers from Colombia, Kenya, Nigeria and Tanzania.
The scientists have been seeking to fortify a single 500 gram adult portion of cassava with essential nutrients, including vitamins A and E, iron and zinc.
Other goals include making the crop more disease-resistant, extending its shelf-life from one day to two weeks and reducing cyanide toxicity.
The scientists now claim to have "demonstrated proof of practice for all the target objectives in three years" since their 2005 start date.
The transgenic cassava plants have undergone a stringent biosafety approval process in the United States, and field trials are currently being carried out at a US Department of Agriculture site in Puerto Rico.
Next on the agenda are field trials in Kenya and Nigeria in 2009, before researchers attempt to combine the traits into a single plant.