1. INTRODUCTION
Nigeria is a very large country, spanning an area of 910.8 thousand square kilometres out of which 77.7 per cent is cultivable (World Bank, 2016). It has the largest population in Sub-Saharan Africa estimated at 180.7 million in 2014 (Central Bank of Nigeria (CBN), 2014), and it is one of the ten most populated country in the world. The country is bordered by the Atlantic Ocean/Gulf of Guinea to the South, Republic of Benin to the West, Republic of Cameroon to the East and it is bordered in the North by Niger and Chad. Its topography ranges from mangrove swampland along the coast to tropical rain forest and savannah to the north. This topography can support various crops and livestock possibilities and the earths’ crust is rich in so many minerals. Yet Nigeria remains a poor country, with a per capita Gross Domestic Product (GDP) of less than 3,000 United States of America Dollars (US$) and a poverty rate of 72 per cent (CBN, 2014).
That Nigeria has remained a poor country after 56 years of independence is partly due to the fact that a substantial proportion of the wide expanse of agricultural lands are yet to be cultivated while most of the minerals are yet to be exploited. Most importantly, the discovery of substantial quantities of petroleum in the country shortly after independence in the late 1960s and the attractive world crude oil prices shifted emphasis away from agriculture and other sectors of the economy. Available statistics indicated that crude oil exports fetched Nigeria only N8.8 million at independence in 1960 and this constituted just 2.7 per cent of total export earnings, while non-oil exports amounted to N321.2 million, constituting 97.3 percent of total exports in the same period. But by 1976, the table turned and the value of oil exports increased astronomically to N6,321.6 million, constituting 93.6 per cent of total exports, while the proportion of non-oil exports in Nigeria’s foreign earnings had declined substantially to 6.4 per cent at N429.5 million (Evbuomwan, 1996), and this trend has remained over the years (Tables 1a and 1b).
Despite the fact that oil exports constitute a substantial proportion of Nigeria’s export earnings, its importance in the GDP is lower than that of the non-oil sector (Table 2a) and particularly worrisome is the fact that its fortunes have been on the downward trend in recent years with dire consequences for the Nigerian economy. For instance, the contribution of crude petroleum and natural gas to the nations GDP declined from 14.95 per cent in 2011 to 9.61 per cent in 2015, whereas, the agricultural sector contributed 23.35 and 23.11 per cent to the nations GDP in these respective periods. In addition, oil refining has been contributing less than 0.5 per cent to the nation’s GDP as Nigeria merely exports crude oil, whose price is determined exogenously (Table 2b). Unfortunately, crude oil price has been on the decline in the last four years. From an average of US$ 113.5 in 2012, a barrel of crude oil now sells for less than US$50.00 (CBN, 2014 and 2016). It is also pertinent to note that, the bulk of the Nigerian population earn their living from the non-oil sector with the agricultural sector alone providing employment for over 70.0 per cent of the populace, while agricultural produce and semi-processed agricultural commodities have constituted the bulk of non-oil export earnings