AllAfrica: Agroforestry, diversification of crops with legumes and other practical measures must be scaled up to end hunger while meeting the challenge of climate change, United Nations Secretary-General Ban Ki-moon told a global conference on the issue today. "Agriculture is a major contributor to global greenhouse gas emissions. At the same time, famers worldwide are increasingly feeling the effects of a warming climate," Mr. Ban said in a message to the Third Global Conference on Agriculture, Food and Nutrition...