EFFECT OF SOCIAL CAPITAL ON PRODUCTIVITY OF CASSAVA FARMERS IN OGUN STATE, NIGERIA

Nigeria is an agriculturally labor-intensive economy and the protection and utilization of the labor resource to guarantee the highest productivity are of immense vitality to the growth of the agricultural sector. This study assessed the relationship between the social capital and the productivity of cassava farmers in Ijebu North-East Local Government Area of Ogun State. A purposive sampling procedure was employed in the study. Data were collected from one hundred and thirty-nine cassava farmers by the use of a well-structured questionnaire. Data were analyzed using descriptive statistics, total factor productivity and ordinary least squares model. The mean age and household size of cassava farmers were 44.2±9.9 years and 6.0±3.1 respectively. The density of memberships in associations was 2.7±1.3. The average meeting attendance index by farmer was three out of four meetings (77.2%). The association membership was moderately diversified with a heterogeneity index of 59.2% and farmers participated in one out of four decision making processes of their associations. A monthly cash contribution of farmers to associations was low (N132.04±N107.67) and the trust index was 0.296. Farmers cultivated an average of 1.25 ha with total factor productivity of 0.096kg/N. Results show that age of the farmer, age squared (life cycle), household size, farm size, cash contribution and decision making significantly determined the productivity of cassava farmers in the study area. Social capital variables significantly influenced cassava farmers’ productivity. It is therefore suggested that policy makers interested in farmers’ production output should make active participation in local level institutions compulsory.


Introduction
The Nigerian agricultural sector contributes about 35% of Gross Domestic Product (GDP) of the economy and it employs over 70% of the population (Oxfam, 2007). Notwithstanding rapid levels of the rural-urban movement, poor rural inhabitants still account for about half of the Nigerian populace (ESA/UN, 2009;Akinbami and Fadare, 1997). This sector is still dominated by small-scale farmers accounting for over 90% of the total output of food crops, especially roots and tubers, for example cassava (IFAD, 2006).
Cassava (Manihot esculenta) is a staple food of most households in Nigeria and other developing countries. It is a critical factor in poverty alleviation and cultivation, processing and marketing of the crop provide employment opportunities for the rural and urban population. According to Nweke et al. (2002), the crop has the potential for bridging the food gap and famine rarely occurs where cassava is widely cultivated. Cassava farming is mainly practiced by small-scale farmers and their production is mainly characterized by low productivity.
A low agricultural output in Nigeria is due to an array of factors such as poor soil management practices, the adverse impact of climate change on the environment, non-availability and high cost of inputs, crude farm tools, and obsolete farming practices. The persistent welfare loss and food insecurity, as a result of the poor agricultural output, account for 70 percent of Nigerians who are food insecure (Orewa and Iyangbe, 2009). According to Akpabio (2008), smallscale farmers in Africa have remained the central focus of development efforts based on the belief that policies targeting at them will positively impact on their food production efforts and poverty reduction.
Despite efforts made by various past governments in Nigeria and aimed at improving agricultural productivity and efficiency of the rural farmers who are the major participants of agricultural production, the country is still food insecure (Simonyan, Olukosi and Omolehin, 2010). One of these efforts is Root and Tuber Expansion Program geared towards increasing root and tuber crop production. In 2002, the Presidential Initiative on Cassava Production and Export was introduced by the Nigerian government aimed at using cassava production as the engine of economic growth for the nation. Also in 2011, the Nigerian government unfolded Agricultural Transformation Agenda (ATA) with a specific goal to increase cassava production in Nigeria to 17 million metric tons from 20 million metric tons targeted for the production of staple food crops between 2011 and 2015 in the country (National Planning Commission, 2011).
The availability of production resources and use of these inputs in the right proportion are necessary to achieve increased output and productivity in Nigerian agriculture (CBN 1999;Balogun, 2011). In order to boost farmers' productivity and income of farmers, various past governments in Nigeria have been trying to encourage rural farmers in diverse ways to adopt modern production technologies at various levels. Nevertheless, there are some constraints impeding these efforts, for example the inability of rural farmers to secure the necessary collateral to enable access to loans from financial institutions.
Social capital has increasingly gained facets in many aspects of agricultural production and rural development in most developing countries. This has led to perceived positive costs of social capital in development and opening of opportunities to those who lack access to financial, human or natural capital (Meinzen-Dick, DiGregorio and McCarthy, 2004). Rural areas are naturally bestowed with natural capital which includes land and water coupled with adequate human capital which is acquired as a result of years of experience in cassava production and are undermined by the other types of capital such as financial and social capital. These capital resources are therefore converted into physical assets for increased production (World Bank, 2007). To meet the increasing demand of production, farmers need financial assistance but unfortunately they cannot provide collateral required by financial institutions. The farmers are therefore hindered from making any approach to these institutions for credit to improve and increase production. This has given rise to alternative measures of raising financial capital (social networks) in order to transform available natural inputs into physical products. Credit is an essential factor for input acquisition by the rural poor. Credit access and proper usage have also been identified to enhance rural household production output in Nigeria (Okunmadewa, 2001;Okoruwa and Oni, 2002;Balogun, 2011). However, the difficulties created by formal credit sources such as high interest rates and terms for such loans are always discouraging (Balogun, 2011).
Limited accessibility to credit reduces productivity and income of rural small-scale farmers. Obisesan (2013) has revealed that farmers who are members of cooperatives have easier access to credit. Thus, association membership is a synonym for social capital and therefore provides the necessary collateral security that most formal credit institutions demand. Social capital is therefore perceived as a substitute for mobilizing financial capital needed for transforming of natural resources to physical assets and can be accumulated through active participation in local level institution activities (Baron et al., 2000). It has now become pertinent to investigate the effects of social capital on the productivity of cassava farmers in Ijebu North-East Local Government Area of Ogun State, Nigeria. The specific objectives are: 1. to profile the socio-economic characteristics and social capital dimensions of cassava farmers; 2. to determine the total factor productivity of cassava farmers, and 3. to examine the determinants of the productivity of cassava farmers.
Conceptual/theoretical framework and literature review The term 'social capital' refers to elements like trust, civic spirit, solidarity and readiness to associate, build and maintain communities (Putnam, 1993). Social capital, as defined by Astone and Mclanahan (1991), also refers to the relationship between different family members that determines how individual members can take advantage of whatever financial and human capital other family members possess. Social capital comprises informal forms of institutions and organizations that are based on an emotional attachment to a group, networks, and associations that create shared knowledge, mutual trust, social norms, and unwritten rules (World Bank, 1998;Putnam et al., 1993;Durlauf and Fafchamps, 2005).
The hypothesized relationship between social capital and agricultural productivity is synergetic and interrelated. Social capital impacts agricultural productivity indirectly by affecting the supply of labor, both household and hired, as well as by being a source of information for households. Households process this information to make technology adoption decisions that have direct impacts on their levels of productivity. Social networks may also indirectly influence agricultural productivity by impacting farming practices and household's propensity to adopt new technologies through social networks (Katungi, 2007;Liverpool and Winter-Nelson, 2010). The concept of social capital as an important determinant of economic development is attracting increasing attention among development economists. Social capital in every sense is one of the fundamental factors of development. No country can achieve sustainable economic expansion without substantial investment in human capital. Social capital is an informal norm that promotes cooperation between individuals. Social capital enriches people's understanding of themselves and the world.
Social capital manifested in community-based organizations or in personalized social networks has been found to play an important role in the adoption of crop technologies (Isham, 2002;Katungi, 2007) and production output of banana farmers (Odebode and Adetunji, 2010).
Van den Broeck and Dercon (2007) have analyzed whether agricultural information flows give rise to social learning effects in banana cultivation in Nyakatoke, a small Tanzanian village, using information on socio-economic characteristics and banana farmers' families, neighbours and informal insurance group members. The results have shown that social effects are strongly dependent on the reference group and no effects of social networks are found in distance-based groups and only kinship related groups generate the endogenous social effects that produce positive externalities in banana output.

Area of study
The study was conducted in Ijebu North-East Local Government Area (LGA) of Ogun State, Nigeria. The LGA is one of the local governments in Ogun state. This area was chosen because of a high concentration of cassava farmers. The major economic activities of the inhabitants of LGA are farming and trading.
Sampling procedure and size: The primary data employed for this study were gathered using a well-structured questionnaire. One hundred and thirty-nine cassava farmers were purposively selected. Data obtained from these farmers were based on socio-economic/demographic characteristics, local level institution activities, cassava productive activities (input and output), household consumption expenditure and income.
Analytical techniques: The tools employed included descriptive statistics, total factor productivity and regression model.
(i) Descriptive: Descriptive statistics which show the frequency, mean, standard deviation and percentage were used to profile the socio-economic characteristics of the cassava farmers.
The explanatory variables used in this study were drawn substantially from the works of Rahman (2007), Key and McBride (2003), Yusuf (2008) and Durojaiye et al. (2014). The selection of the variables for the total factor productivity model in this study was guided by findings in the literature (Rahman 2007;Key and McBride, 2003).

Results and Discussion
The summary statistics of some of the variables included in the regression are shown in Table 1. The results show that the mean age and household size of cassava farmers were 44.2±9.9 years and 6.0±3.1 respectively. Farmers cultivated an average of 1.25 ha. The density of memberships in associations was 2.7±1.3. The average meeting attendance index by farmer was three out of four meetings (77.2%). The membership of the association was highly Effect of social capital on productivity of cassava farmers in Ogun State, Nigeria 105 diversified with the heterogeneity index of 59.2% and farmers participated in one out of four decision making processes of their associations. A monthly cash contribution of farmers to associations was low (N132.04±N107.67) and trust index was 0.296.
The socio-economic characteristics and social capital dimensions of cassava farmers are presented in Table 2. The results show that female farmers had the higher heterogeneity index of 60.2%, that is, they were more diversified in the associations they belonged to. Male cassava farmers had a slightly higher average value of meeting attendance in their association meetings in their local association than their female counterparts. The results show that farmers mostly attended twothirds of their association scheduled meetings because of benefits and opportunities there. The commitment of male farmers over the female counterparts in their associations is reflected in slightly higher cash contributions and involvement in decision making regarding association matters. The results also show that male cassava farmers had some level of trust than female farmers; however, male farmers had the higher density of membership in associations. Table 2 also shows that cassava farmers aged less than 30 years and more than 50 years had high percentages of diversity in their social institutions with values of 64.8% and 62.4% respectively. This could be due to the fact that some the farmers were young and not mature enough to take some decisions or too old and already experiencing weakness or reduction in active farming activities. The results related to meeting attendance reveal that members of all age categories with the exception of those aged less than 30 years attended three out of four scheduled meetings of their various associations. However, the highest representation of 80.2% for meeting attendance was recorded for the group of members aged 30 40 years. The highest cash contribution (N156.30) was recorded for the group of farmers aged under 30 years while the least, N110.0, was contributed by farmers aged above 50 years. The reason could be attributed to a reduction in income as age increases or to a reduction in their income generating activities due to health reasons. These results support the findings reported by Adepoju and Oni (2012) that cash contribution to association by household's head declines as age increases. The majority (35.9%) of the farmers aged above 50 years participated in decision making in their associations, while those aged under 30 years participated least (25%). The results reveal that all the age groups participated in less than half of decision making processes in their various associations. The result shows that the highest level of trust was observed in the group of farmers aged less than 30 years and the lowest level was recorded in the group of members aged 30 40 years. Table 2 reveals that the 30 40 age group accounted for the density of membership (3 members) in local level institutions, followed by farmers aged 41 50 years and above 50 years. Those aged under 30 years had the lowest membership density. The overall social capital dimensions show that most cassava farmers (62.1% ) were within the age group of 50 years and above and had the highest aggregate social capital. The results indicate that the farmers with no formal education were the most diversified with 60.0% while the least diversified were those with primary education. These results are in line with the findings of Adepoju and Oni (2012) that uneducated households are more diversified than educated ones. Meeting attendance across the educational categories shows that all the farmers had at least 67% meeting attendance. The quest to augument their earnings from other sources might have made attending meetings impossible for them. However, cassava farmers who received tertiary education had the highest value of contribution with an average of N360.0 as their monthly contribution to their various associations. Farmers with no formal education accounted for the least cash contribution with N121.10 as a cash contribution to their associations. This can be attributed to the fact that these people belong to the least paid group, which will likely reflect in their contribution capability to the local level institution. The results reveal that all the educational level categories claimed to partake in a decision making process in their various associations. Farmers with no formal education had the least average value in the decision making processes in their associations. It is observed that as an individual farmer became more educated, the extent of involvement in the decision making process in the associations he/she belonged to increased. The highest social values of more than 50% were observed for farmers educated to tertiary level and farmers with no formal education while the values for those with secondary and primary education were lower. Married farmers were more diversified in their respective association than single, divorced or separated farmers. The results show that they had higher values for meeting attendance (80.9%) and contributed more to their local associations in terms of cash (N136.30) than their single counterparts. The implication is that they would be more committed and would always be ready to do anything to protect their investments in their association. Married cassava farmers contributed more to their local associations in terms of cash (N136.30) than their single counterparts because their wives were always there for processing and marketing operations required for the output. However, as for decision making, married farmers participated slightly more than single farmers in the decision making process in their association. Regarding their marital status, members trusted one another and membership density was slightly higher in the households of married farmers than in the households of single, divorced or separated farmers. The result reveals that the level of trust in married and single cassava farmers was the same. In all, the married farmers had a higher aggregate social capital than the single in the study area.
The average variable cost and the average quantity of output are depicted in Table 3. The total factor productivity was calculated by dividing average output of cassava produced by farmers by the average variable cost. The results show that the average output of cassava farmers was 15,285.71kg while the average variable cost in naira was N158,500. The results suggest that for every N1 incurred in the cassava production there was approximately 0.096kg of cassava produced.
The results of the determinants of the productivity of cassava farmers are presented in Table 4. The results show that age of the farmer, age squared (life cycle), household size, farm size, cash contribution and decision making significantly determined the productivity of cassava farmers in the study area. The results show that a unit increase in cassava farmer's age increased his/her productivity by 0.448 unit. Age had a quadratic relationship with respect to productivity and it was positive for age and negative for age squared. These results imply that as a cassava farmer advanced in age, his/her productivity decreased. The relationship between the age of a cassava farmer and his/her productivity suggests that the older the farmers, the lower the productivity. An additional age to a farmer decreased his/her productivity by 0.517 unit. Therefore, as a farmer grows older the ability to do rigorous farming activities decreases and negatively affects his/her production output. On the other hand, household size was positive and significantly affected farmer's productivity. A 100% increase in the variable increased production output by 12.9%. The positive relationship between household size and total factor productivity suggests that a household with a larger family size tended to have higher productivity than those with a small household; this can be related to the amount of family labor available for farming. The results agree with Atagher (2013) that a large family size leads to an output increase if the members help in the farm. The results indicate that farm size was positive and significantly related to farm productivity. The results further show that a hectare increase in cassava farm increased productivity by 0.133 unit. This is because in a large farm, there are greater opportunities to use modernized tools and skilled laborers that invariably will increase productivity of the farmer. The results indicate there was a positive relationship between a cash contribution of farmers in their local associations and productivity. It therefore suggests that donations, levies, fees and other contributions paid by households in their local institutions went a long way in accessing loans for production and consumption purposes and thereby resulted in increased farm productivity. The results agree with Ajani and Tijani (2009) and Balogun and Yusuf (2011) that a cash contribution to association is presumably a sign of greater interest in the association and serves as a collateral effect for farmers demanding credit from formal credit institutions. However, participation in decision making of the farmers in their various associations reveals that farmers participating in all their association decision making processes increased productivity by 58.0%. This is an indication that farmers who participated actively in decision making in their local level institutions were better positioned to enjoy the benefits coming to their association concerning how to run the farm efficiently.

Conclusion
The study focuses on the effect of social capital on the productivity of cassava farmers in Ijebu North-East Local Government Area of Ogun State, Nigeria. The study reveals that the average age of a cassava farmer in the area was 44.2 years. Household size was 6 members. The results have shown that most cassava farmers had large family sizes. However, farmers in the study area cultivated an average area of 1.25 ha. This study further reveals that the average total factor productivity of the cassava farmers in the study area was 0.096kg/N. The study further shows that socio-economic, farm specific and social capital variables (age, age squared, household size, meeting attendance, farm size, cash contribution, decision making index) significantly influenced cassava farmers' productivity. The results of this study have revealed that there was a need for more investment in social networks in order to improve productivity of farmers and boost cassava production. Based on the findings of this study, the following recommendations have been made to improve cassava farmers' productivity in Ogun State. It is therefore suggested that policy makers interested in improving the living conditions of farmers and their production output should encourage them to increase their participation in their association activities. Farmers should be encouraged to join associations to be able to benefit from programs and training targeted at improving food production in the country.