Tapioca, known also as Cassava or Manioc, is a sturdy root crop providing staple food to more than 800 million people, mainly in African continent. It is also an industrial commodity used for manufacture of cattle feeds and starch and its down stream products. With a world production of about 200 million tons, Africa accounts for more than 50%, the rest being shared by Asian and Latin American continents. Though it is not a nutritious food, Tapioca serves the purpose of keeping famine and starvation away for many people in Africa. Its sturdiness can be gauged by the fact that the tuber can stay underground for more than 3 years with very little physiological damage but are vulnerable to more than 20 pests and diseases. The latest threat to it comes from the disease "brown streak" which is threatening to shake the very foundation of food security in Africa.
"Inside its tan skin, the white flesh was riddled with necrotic brown lumps, as obviously diseased as any tuberculosis lung or cancerous breast. "Even the pigs refuse this," she said. The plant was what she called a "2961," meaning it was Variant No. 2961, the only local strain bred to resist cassava mosaic virus, a disease that caused a major African famine in the 1920s. But this was not mosaic disease, which only stunts the plants. Her field had been attacked by a new and more damaging virus named brown streak, for the marks it leaves on stems. That newcomer, brown streak, is now ravaging cassava crops in a great swath around Lake Victoria, threatening millions of East Africans who grow the tuber as their staple food. Although it has been seen on coastal farms for 70 years, a mutant version emerged in Africa's interior in 2004, "and there has been explosive, pandemic-style spread since then," said Claude M. Fauquet, director of cassava research at the Donald Danforth Plant Science Center in St. Louis. "The speed is just unprecedented, and the farmers are really desperate."
Cassava mosaic virus (CMV) which had crossed continental barriers and jumped the seas to spread to all over the world is still a potent predator disease vector and if brown streak is able to repeat the "feat" of CMV, it is a question of time before Tapioca has to face extinction. Containment of this dreaded plant disease must assume priority for an organization like FAO and it should not be allowed to spread further beyond its present reach.