CHAPTER ONE
1.0 INTRODUCTION
Cowpea (Vigna unguiculata) is a leguminious crop with a very vast importance and plays an active role in maintaining the ecosystem, nutrient requirement and the economy of many countries. A considerable amount of cowpea of more than 5.4 million tons are produced in the world annually with Africa producing nearly 5.2 million tons and Nigeria recorded as the greatest producers accounting for about 61% of cowpea production in Africa and 58% of the world cowpea production [IITA, 2009]. According to Wikipedia on Cowpea (2012), and IITA,( 2009); cowpea is one of the most important food legume crop in the semi arid tropics covering Asia, Africa, Southern Europe, and Central America and originated and domesticated in Southern Africa and Asia. [wikipedia/cowpea, 2012. IITA, 2009].However, some constraint such as agro-ecological constraint, cultivation in marginal and sub marginal land, unpredictable and poor distributed rainfall, lack of soil fertility, seasonal constraint, low productivity, susceptible to pest and disease, flower shedding, tendril formation, lack of adaptive high yielding varieties have been reported to inhibit production of cowpea in some area [Maria et.al,2008].