(a) Four roles of government in agricultural production are:
(i) Provision of financial assistance in form of loans and credit facilities to farmers
(ii) Establishment of agricultural programmes such as Farm Settlement Scheme, Green Revolution, Operation feed the Nation, etc.
(iii) Provision of farm inputs such as fertilizers, farm tools and implements, seeds, agro chemicals etc.
(iv) Provision of basic amenities like pipe borne water, electricity and hospital in rural areas.
(b) four traditional systems of land ownership in Nigeria and their disadvantages are :
(i) Communal and Tenure System: The land belongs to the community and only members of the family can have may not have access to the use of such land. Disadvantages: (1) Mechanization may be difficult. (2) Non-members of the community may not have access to the use of the land.
(ii) Land tenure by Inheritance: This is a situation where land is inherited from one's parents. Disadvantage: It leads to land fragmentation
(iii) Lease hold system: This requires the payment of a fee or tenancy for land used over a stated period of time. Disadvantage: The farmer cannot use the land s as collateral security.
(iv) Purchase: This is the total acquisition of land for a fee. Disadvantage: Ownership may be challenged or difficult to establish