 From VOA Learning English, this is the Agriculture Report. Cassava is a very important crop in many countries. More than 160 million people across Africa depend on the plant for food or to earn money. The continent produces 60% of the world's cassava. In May, the United Nations Food and Agriculture Organization reported that cassava production had increased by 60% worldwide since 2000. Agriculture experts had been expecting world cassava production to grow even more during the next 10 years. But those expectations have been crushed. Plant diseases are attacking cassava crops in East and Central Africa. Two diseases are the cassava-brown streak virus and the cassava-mosaic virus. The Food and Agriculture Organization says brown streak disease does more damage since it affects the root of the crop. Luca Alanovi is the acting director of the FAO in East and Central Africa. He says the agency has taken steps to improve the situation, but the problem is not getting better. She says decisions on how to handle the problem will have a huge impact on the food security of people in Central Africa. Dominique DeVoe heads the European Union Rural Development and Agricultural Program in Kenya. She says the cassava diseases have changed over the years. She says early research slowed the disease, but the disease changed form and new research is needed. The FAO says at least $100 million is needed to study the diseases and support clean farm production. Experts say failure to stop the disease means cassava disease will likely invade Nigeria, the biggest producer of cassava in Africa. For VOA Learning English, I'm Carolyn Presuti.