ECONOMIC ANALYSIS OF SESAME PRODUCTION AMONG SMALL- HOLDER FARMERS IN BENUE STATE, NIGERIA

CHAPTER ONE: INTRODUCTION

1.1 Background of the Study

Sesame (Sesamum indicum L.), also known as benniseed, is one of the oldest oilseed crops cultivated by humans, valued for its high-quality oil (containing approximately 40-50% oil with high proportions of unsaturated fatty acids), protein-rich seed cake (30-40% protein), and versatility for both domestic consumption and industrial use. Globally, sesame production has expanded significantly over the past three decades, driven by growing demand for sesame oil in food processing, pharmaceutical applications, cosmetic products, and the use of sesame seeds in confectionery and bakery products (FAOSTAT, 2020). The crop is particularly well-suited to smallholder production systems in semi-arid and tropical regions due to its drought tolerance, relatively low input requirements, short growing cycle (90-120 days to maturity), and ability to grow on residual soil moisture after cereal crops (Ashri, 2019). (FAOSTAT, 2020; Ashri, 2019)

Nigeria has emerged as a major player in the global sesame market, ranking among the top sesame-producing countries in the world and as the largest producer in West Africa. Current estimates place Nigeria’s annual sesame production at approximately 500,000-700,000 metric tons, cultivated on an estimated 600,000-800,000 hectares, primarily by smallholder farmers in the northern and north-central states (NBS, 2020). The crop has gained increasing importance as an export commodity, with Nigeria exporting over 200,000 metric tons of sesame seeds annually to major markets including Japan, China, Turkey, South Korea, and European Union countries, generating substantial foreign exchange earnings. Unlike many other agricultural commodities that face tariff barriers or quality restrictions, Nigerian sesame enjoys strong demand in international markets due to its high oil content and favorable flavor profile (Nigerian Export Promotion Council, 2019). (NBS, 2020; Nigerian Export Promotion Council, 2019)

Benue State, located in the North-Central geopolitical zone of Nigeria, has emerged as an important sesame-producing region, although it is historically better known for yam, cassava, rice, and soybean production. The state’s diverse agroecological conditions—spanning the Guinea savannah in the north and derived savannah in the south—provide suitable environments for sesame cultivation, particularly in the drier northern Local Government Areas where rainfall is moderate (1,000-1,300 mm annually) and well-distributed during the growing season (Benue State Ministry of Agriculture, 2020). Sesame production in Benue has expanded over the past decade as farmers have responded to attractive market prices, the crop’s drought tolerance (which provides a hedge against rainfall variability), and its compatibility with the state’s existing cropping systems (often grown as a second crop after early-maturing cereals or intercropped with other legumes). (Benue State Ministry of Agriculture, 2020)

Smallholder farmers dominate sesame production in Benue State, typically cultivating sesame on plots ranging from 0.5 to 2.0 hectares, using a combination of family labor and, in some cases, hired labor for land preparation, planting, weeding, and harvesting. Sesame is attractive to smallholders for several reasons: it requires relatively few purchased inputs compared to cereal crops; it can be grown on residual soil fertility following other crops; it is less susceptible to certain pests and diseases that affect other oilseeds; and it has a relatively short growing cycle, allowing farmers to double-crop or to fit sesame into their rotation patterns (Ike and Agwu, 2018). However, sesame production is not without challenges: the crop is labor-intensive at harvest (hand-harvesting, bunching, threshing, cleaning), is susceptible to bird damage and shattering (seed drop from mature capsules), and faces quality constraints (presence of foreign matter, high moisture content, discoloration) that affect market prices (Odebode and Ezeh, 2019). (Ike and Agwu, 2018; Odebode and Ezeh, 2019)

The economic analysis of sesame production examines the relationships between inputs (land, labor, seed, fertilizer, crop protection, capital) and outputs (sesame seed yield, quality, revenue), with the goal of understanding profitability, efficiency, and the factors that influence economic performance. For smallholder farmers, the economic viability of sesame production depends on: yield levels (typically 0.5-1.2 tons per hectare under smallholder management, compared to potential yields of 1.5-2.0 tons per hectare with improved practices); seed prices (which are volatile and influenced by international market conditions and quality); input costs (which vary with location, season, and access to subsidized inputs); labor costs (particularly at harvest, which accounts for 30-50% of total labor input); and post-harvest handling and marketing costs (Ogunsola and Adebayo, 2020). Understanding these economic relationships is essential for assessing whether sesame production contributes to household welfare and whether interventions to improve productivity and profitability are warranted. (Ogunsola and Adebayo, 2020)

The profitability of sesame production in Benue State varies considerably across farmers, seasons, and locations, influenced by a range of technical, economic, institutional, and environmental factors. At the technical level, adoption of improved practices—including improved sesame varieties (e.g., E8, NCRIBEN-01M, NCRIBEN-02L), recommended planting densities, appropriate fertilizer application (especially phosphorus and potassium), timely weed management, and proper post-harvest handling—can significantly increase yields and improve seed quality, thereby enhancing profitability. At the economic level, access to credit, input prices, output prices, and labor costs affect net returns. At the institutional level, extension services, farmer group membership, and market access influence productivity and profitability. At the environmental level, rainfall variability, soil fertility, and pest/disease pressure affect yield realizations (Akande and Ogunwale, 2019). (Akande and Ogunwale, 2019)

The socio-economic characteristics of sesame farmers in Benue State—including age, educational attainment, household size, farming experience, farm size, asset ownership, access to credit, and extension contact—systematically influence both the technical and economic performance of sesame production. Older farmers may have accumulated more experience but may be less likely to adopt improved varieties or practices. More educated farmers may better understand market information, quality requirements, and the economics of input use. Larger farm sizes may allow economies of scale in input purchasing and marketing, but may also be associated with lower intensification. Access to credit enables purchase of improved seeds, fertilizers, and hired labor at optimal times. Extension contact can improve knowledge of recommended practices, pest management, and post-harvest handling (Rogers, 2003; Feder and Umail, 2020). (Rogers, 2003; Feder and Umail, 2020)

The cost structure of sesame production in Benue State typically includes both variable costs (which vary with the area cultivated or output level) and fixed costs (which do not vary with output in the short term). Variable costs include: land clearing and preparation (hired labor or opportunity cost of family labor); seed (improved or local varieties); fertilizer (typically NPK, sometimes single superphosphate for phosphorus); herbicides (for weed control, though many farmers rely on manual weeding); pesticides (for insect pest management, especially for sesame webworm and leaf roller); harvesting and threshing labor; and transportation to market. Fixed costs include: depreciation of farm tools (hoes, cutlasses, sprayers) and, where applicable, land rental payments. The relative importance of different cost components varies; for many smallholder farmers, labor (especially harvest labor) represents the largest single cost item, followed by seed and fertilizer (Olayemi and Adebayo, 2018). (Olayemi and Adebayo, 2018)

The revenue side of sesame production is determined by both yield (kg per hectare) and price (NGN per kg). Sesame yields in Benue State vary widely depending on variety, soil fertility, rainfall distribution, weed and pest management, and harvest efficiency. Reported average yields range from 0.4 to 0.8 tons per hectare for farmers using local varieties and traditional practices, and 0.9 to 1.3 tons per hectare for farmers using improved varieties and better management (Benue State Ministry of Agriculture, 2020). Sesame seed prices are highly seasonal and also vary by quality: white/cream-colored seeds (preferred in many export markets) command premium prices (typically NGN 250-400 per kg depending on season), while mixed or discolored seeds trade at substantial discounts (20-40% lower). Farmers who can produce high-quality, clean, well-dried sesame at the right time (immediately after harvest when prices are often higher) can substantially improve their profitability (NEPC, 2019). (Benue State Ministry of Agriculture, 2020; NEPC, 2019)

The marketing of sesame in Benue State involves multiple channels and actors, with implications for the prices farmers receive and thus the profitability of production. The simplest channel is direct sale to local village assemblers (middlemen) who buy small quantities from individual farmers at farm-gate prices, then aggregate and transport to larger markets. Farmers may also sell to rural periodic markets (weekly markets), to licensed buying agents of larger trading companies, or directly to sesame processing/export companies if located nearby (Baba and Musa, 2019). Each channel has different price implications: farm-gate prices are typically lowest (reflecting the assembler’s marketing costs and profit margin); prices at periodic markets are somewhat higher (but require transport costs and time); and prices at company buying points may be higher still but require meeting stricter quality standards. Many smallholder farmers face constraints in accessing higher-priced market channels due to limited market information, small volumes, transportation costs, and lack of bargaining power (Obi and Ezeh, 2020). (Baba and Musa, 2019; Obi and Ezeh, 2020)

The efficiency of sesame production—the relationship between inputs and outputs—is a key dimension of economic analysis. Technical efficiency refers to the ability to produce maximum output from a given set of inputs (or to produce a given output with minimum inputs). Allocative efficiency refers to the use of inputs in optimal proportions given their prices and the output price. Economic efficiency combines both technical and allocative efficiency. Studies from other sesame-producing areas in Nigeria (e.g., Nasarawa, Jigawa, Kogi, Katsina States) have reported mean technical efficiency scores ranging from 0.55 to 0.85, indicating that there is substantial room for improving productivity without increasing input use—simply by better management, more timely operations, and adoption of recommended practices. No such efficiency analysis has been conducted for sesame farmers in Benue State (Ogunniyi and Olagunju, 2019). (Ogunniyi and Olagunju, 2019)

The profitability of sesame production also depends critically on the treatment of family labor. Many economic analyses treat family labor as a “free” input (excluding it from variable costs), which overstates profitability compared to accounting for family labor at its opportunity cost (the wage rate the farmer could earn working elsewhere). In Benue State, where off-farm labor markets exist and family members could potentially work on other farms or in non-farm activities, the opportunity cost of family labor is positive and should be included for accurate economic analysis. Studies that include family labor costs typically report lower net returns but more realistic estimates of whether sesame production is economically viable compared to alternative uses of family labor (Ike and Agwu, 2018). This distinction is important for policy: if sesame is only profitable when family labor is treated as free, then it may not be a sustainable livelihood strategy as off-farm opportunities expand. (Ike and Agwu, 2018)

The constraints facing sesame producers in Benue State are multiple and interconnected, affecting both productivity and profitability. Production constraints include: limited availability of improved sesame seeds (most farmers rely on saved seed of local varieties with low yield potential); declining soil fertility (due to continuous cultivation without adequate nutrient replacement); pest and disease pressure (sesame webworm Antigastra catalaunalis, leaf roller, phyllody disease); bird damage (especially during seed maturation); and climate variability (drought or excessive rainfall affecting flowering and seed set). Post-harvest constraints include: labor-intensive threshing and cleaning (using traditional methods); drying constraints (inadequate drying surfaces, weather dependence); and storage losses (pests, moisture, mould). Marketing constraints include: price volatility; lack of market information; limited bargaining power; transportation difficulties (poor road conditions); and limited access to credit for pre-harvest financing (Odebode and Ezeh, 2019). (Odebode and Ezeh, 2019)

The role of agricultural extension services in improving sesame production economics is substantial but often underutilized. Extension agents can provide information on: improved sesame varieties suitable for different areas; recommended agronomic practices (planting density, fertilizer rates, timing of operations); pest identification and management; harvesting and post-harvest handling (threshing, cleaning, drying, storage); quality standards for different markets; and market price information. However, extension contact among sesame farmers in Benue State is reported to be low, with estimates suggesting that less than 15% of sesame farmers have had any contact with extension agents in the past year. Reasons include inadequate numbers of extension agents, lack of extension programming specifically focused on sesame (which is often treated as a minor crop), and limited transport and logistical support for extension operations (Benue State Ministry of Agriculture, 2020). (Benue State Ministry of Agriculture, 2020)

Access to credit is widely recognized as a critical enabling factor for agricultural productivity and profitability, enabling farmers to purchase improved seeds, fertilizers, and other inputs at the right time. In Benue State, sesame farmers face significant constraints in accessing formal credit from banks and microfinance institutions: collateral requirements (land titles, which many smallholders lack), high interest rates, complex application procedures, and limited branch presence in rural areas. Informal credit sources (moneylenders, input suppliers, cooperatives, family) are more accessible but may carry high interest rates or impose social obligations. The lack of credit limits farmers’ ability to invest in productivity-enhancing inputs, perpetuating low yields and low profitability. Some farmers have accessed credit through sesame cooperatives or through input credit arrangements with buying agents (who provide seeds and fertilizers in exchange for exclusive purchase of output), but these arrangements are not universally available (Obi and Ezeh, 2020). (Obi and Ezeh, 2020)

Previous economic analyses of sesame production in Nigeria have been conducted in several states, including Nasarawa (Ogunsola and Adebayo, 2020), Jigawa (Baba and Musa, 2019), Katsina (Akande and Ogunwale, 2019), and Kogi (Ike and Agwu, 2018). These studies have consistently reported that sesame production is profitable (positive gross margins and net returns) under most conditions, with profitability varying with variety (improved varieties more profitable), access to extension (extension contact associated with higher profitability), and market channel (direct sale to exporters more profitable than sale to village assemblers). However, these studies have also reported wide variation in profitability across farmers, with the least profitable quartile of farmers sometimes earning negative net returns (when family labor is valued). No previous economic analysis of sesame production has been conducted specifically for Benue State, despite the state’s growing importance as a sesame-producing region. This gap is significant because Benue’s agroecological conditions, farming systems, market access, and institutional environment differ from those in other sesame-producing states (Ogunniyi and Olagunju, 2019). (Ogunsola and Adebayo, 2020; Baba and Musa, 2019; Akande and Ogunwale, 2019; Ike and Agwu, 2018; Ogunniyi and Olagunju, 2019)

The conceptual framework for this study draws on production economics theory, which analyzes the relationship between inputs and outputs, and the agricultural household model, which recognizes that farm households are both producers and consumers. The production function approach specifies sesame output as a function of inputs (land, labor, seed, fertilizer, etc.), with the parameters of the function indicating the productivity of each input. Profitability is derived from output, prices, and input costs. Efficiency analysis (using stochastic frontier analysis or data envelopment analysis) decomposes differences in productivity into differences in technology (production frontier) and differences in efficiency (distance from the frontier). The empirical framework estimates: (a) gross margin and net return per hectare and per household; (b) the production function (using regression analysis); (c) technical efficiency scores (using stochastic frontier analysis); and (d) the factors influencing efficiency (using two-limit Tobit regression). The study also examines the determinants of profitability using multiple regression analysis (Coelli et al., 2019). (Coelli et al., 2019)

In summary, sesame production among smallholder farmers in Benue State represents an economically significant but under-researched agricultural enterprise with substantial potential for income generation and poverty reduction. The crop’s favorable market prospects, suitability to the state’s agroecological conditions, and low input requirements make it attractive to resource-poor farmers. However, the economic performance of sesame production—profitability, efficiency, and the factors that influence economic outcomes—has not been systematically analyzed for Benue State. Previous studies from other states suggest that sesame is generally profitable but that there is substantial room for improvement through adoption of improved varieties, better agronomic practices, and improved market access. This study therefore seeks to fill this knowledge gap by conducting a comprehensive economic analysis of sesame production among smallholder farmers in Benue State, generating evidence to inform productivity-enhancing interventions, market development, and pro-poor agricultural policy (Ike and Agwu, 2021; Odebode and Ezeh, 2021). (Ike and Agwu, 2021; Odebode and Ezeh, 2021)

1.2 Statement of the Problems

Despite the increasing importance of sesame as a cash crop in Benue State—with production expanding annually in response to attractive market prices and the crop’s suitability to local conditions—the economic performance of sesame production among smallholder farmers has not been systematically documented or analyzed. Policy makers, extension managers, development partners, and farmers themselves lack reliable empirical evidence on: the profitability of sesame production (gross margin and net return per hectare); the efficiency with which farmers convert inputs into outputs; the factors that distinguish more profitable and efficient farmers from less profitable ones; and the constraints that limit economic performance. This knowledge gap hinders evidence-based policy formulation, program design, and farmer decision-making.

Preliminary evidence and anecdotal reports suggest that sesame production in Benue State is characterized by substantial variation in profitability across farmers, seasons, and locations. Some farmers reportedly achieve high net returns (NGN 150,000-300,000 per hectare) from sesame, while others barely break even or incur losses (when family labor is valued). This variation suggests that many farmers are not achieving the economic potential of sesame production, and that interventions to improve productivity, reduce costs, or enhance market access could substantially improve farmer welfare. However, without systematic economic analysis, the magnitude of the profitability gap (actual vs. potential profitability) cannot be quantified, and the specific factors responsible for low profitability cannot be identified.

A first specific problem is the absence of baseline economic data on sesame production in Benue State, including basic parameters such as average yield, average production cost per hectare, average revenue per hectare, and average net return per hectare. While state-level aggregate data exist for area cultivated and total production, these data do not provide the farm-level economic parameters needed for profitability assessment. Furthermore, aggregate data mask variation across different production zones, different types of farmers, and different seasons. Without farm-level economic data, it is impossible to assess whether sesame production is, on average, economically viable, or to identify segments of the farming population for whom sesame is not profitable.

A second problem concerns the lack of knowledge regarding the cost structure of sesame production in Benue State. Which cost components dominate: labor (and within labor, which operations: planting, weeding, harvesting, threshing?), seed, fertilizer, or other inputs? Do costs vary systematically by farm size, variety choice, or location? Understanding the cost structure is essential for identifying potential cost-saving interventions (e.g., mechanization for threshing, improved weed control, group purchasing of inputs) and for assessing the impact of price changes (e.g., if fertilizer prices increase, which farmers are most affected?). Current evidence does not permit such analysis for Benue sesame farmers.

A third problem concerns the relationship between the adoption of improved sesame technologies (improved varieties, fertilizer, pest management) and economic performance. While improved technologies have been promoted by research and extension—including varieties such as E8, NCRIBEN-01M, NCRIBEN-02L, and improved agronomic practices—the actual economic returns to adopting these technologies under Benue farm conditions have not been estimated. Do adopters of improved varieties achieve significantly higher net returns than non-adopters, after controlling for other factors? Do the benefits of adoption justify the additional costs of improved seeds and fertilizers? Without such evidence, promotion of improved technologies rests on technical performance assumptions rather than demonstrated economic returns.

A fourth problem concerns the technical efficiency of sesame production—the ability of farmers to produce maximum output from given inputs. Inefficiency (producing less than the technically feasible maximum) can arise from poor management, untimely operations, inadequate knowledge, or other factors. Inefficient farmers could increase output without increasing inputs simply by improving their practices. The extent of technical efficiency among Benue sesame farmers—the average efficiency score, the range of efficiency scores, and the proportion of farmers operating far below the production frontier—has not been estimated. Furthermore, the factors associated with higher efficiency (e.g., education, extension contact, group membership) have not been identified.

A fifth problem concerns the allocative and economic efficiency of sesame production. Even if farmers are technically efficient (producing maximum output from given inputs), they may be allocatively inefficient if they use inputs in proportions that are not optimal given input and output prices. For example, a farmer may use too much labor relative to fertilizer, or vice versa, resulting in unnecessarily high costs for a given output level. Economic efficiency (technical efficiency times allocative efficiency) measures overall performance in maximizing profit. The allocative and economic efficiency of Benue sesame farmers has not been estimated, nor have the factors associated with higher efficiency been identified.

A sixth problem concerns the relationship between farm size and economic performance in sesame production. In many agricultural systems, there is an inverse relationship between farm size and productivity (smaller farms are more productive per hectare), but the relationship may be different for sesame or may vary depending on labor market conditions and mechanization levels. In Benue, it is unknown whether smaller sesame farms achieve higher net returns per hectare than larger farms, whether there are economies of scale in sesame production (larger farms have lower average costs), or whether there is an optimal farm size range for profitability. Understanding the farm size-profitability relationship is important for targeting interventions and for assessing whether land redistribution or consolidation would enhance sesame sector performance.

A seventh problem concerns the marketing of sesame and its effect on profitability. Farmers who sell through different marketing channels (village assemblers, periodic markets, direct to buying agents, cooperatives) likely receive different prices, and thus have different profitability levels. Farmers who can store sesame and sell later (when prices are higher) may also achieve higher profitability, but storage involves costs and risks (pest damage, moisture, theft). The relationship between marketing channel choice, storage decisions, and profitability has not been analyzed for Benue sesame farmers. Furthermore, the factors that enable farmers to access higher-price marketing channels (e.g., information, volumes, quality, location, social networks) have not been identified.

An eighth problem concerns the measurement and treatment of family labor in economic analysis. Sesame production is labor-intensive, particularly at harvest, and most of this labor is provided by family members (household heads, spouses, children). The standard approach in profitability analysis is to either: (a) exclude family labor from costs (calculating “gross margin”), which yields an estimate of returns to family labor; or (b) value family labor at a shadow wage or market wage rate (calculating “net return”), which yields an estimate of economic profit. Both approaches are informative but answer different questions. Neither approach has been systematically applied to Benue sesame production, so there is no evidence on: the returns to family labor in sesame (how much value is generated per day of family labor); whether returns to family labor exceed off-farm wage rates (indicating whether sesame is a competitive use of family labor); or the distribution of these returns across different types of households.

A ninth problem concerns the gender dimensions of sesame production economics. In Benue State, both men and women participate in sesame production, but their roles differ: men typically prepare land, make major decisions about input purchases, and handle sales; women often participate in planting, weeding, and some harvesting and post-harvest activities. The profitability of sesame production may differ systematically between male-managed and female-managed plots, or between male-headed and female-headed households, due to differences in access to inputs, labor, credit, extension, and markets. Furthermore, the intra-household distribution of sesame income (who controls revenue from sales) has implications for household welfare and women’s economic empowerment. These gender dimensions have not been examined in the Benue sesame context.

A tenth problem concerns the constraints that limit sesame profitability, and the strategies that farmers employ to overcome them. Farmers may face multiple constraints: lack of access to improved seeds; inability to afford fertilizers; labor shortages at critical times (especially harvest); limited knowledge of pest management; poor market access (distance, transport costs, information); lack of credit for pre-harvest financing; and climate risks (drought, untimely rainfall). The relative importance of these constraints for different farmer groups has not been quantified for Benue. Furthermore, the coping strategies farmers employ—e.g., using saved seed of local varieties, reducing fertilizer rates, borrowing from moneylenders, selling at farm gate despite low prices—may have consequences for profitability that are not well understood.

An eleventh problem concerns the risk and uncertainty facing sesame producers and their effects on economic decisions. Sesame prices are volatile, influenced by international market conditions, domestic production levels, and seasonal factors. Yields are variable, affected by rainfall distribution, pest and disease outbreaks, and bird damage. Farmers who are risk-averse may make decisions (e.g., planting less area, using lower rates of fertilizer, avoiding improved varieties) that reduce expected profitability but also reduce downside risk. The risk environment for sesame in Benue—the magnitude of price and yield variability, the correlation between the two, and the extent of risk that is insurable or diversifiable—has not been characterized. Consequently, the extent to which observed suboptimal economic performance reflects rational risk management rather than inefficiency cannot be determined.

A twelfth problem concerns the comparability of economic performance across different producing areas within Benue State. The state’s sesame production is concentrated in the northern LGAs (e.g., Gwer West, Guma, Makurdi, Tarka, Buruku, etc.), but these areas differ in soil type, rainfall patterns, market access (proximity to major roads and markets), and institutional environment (extension coverage, cooperative presence). It is plausible that profitability and efficiency differ systematically across these areas, with implications for targeting of interventions and for understanding the external validity of findings from any single area. No comparative analysis of sesame production economics across Benue LGAs has been conducted.

In summary, the economic analysis of sesame production among smallholder farmers in Benue State is characterized by a substantial knowledge gap. Despite the crop’s growing importance, there are no systematic empirical estimates of: profitability (costs, returns, net margins) at the farm level; technical, allocative, or economic efficiency; the factors that influence profitability and efficiency; the effects of improved technology adoption on economic outcomes; the role of marketing channels and market access; the gender dimensions of production economics; the constraints that limit economic performance; or the risk environment. This study therefore seeks to fill these gaps by conducting a comprehensive economic analysis of sesame production among smallholder farmers in Benue State, generating evidence to inform productivity-enhancing interventions, market development, and agricultural policy.

1.3 Aim of the Study

The aim of this study is to conduct an economic analysis of sesame production among smallholder farmers in Benue State, Nigeria, focusing on profitability, efficiency, and the factors influencing economic performance.

1.4 Objectives of the Study

The specific objectives of this study are to:

1. Describe the socio-economic characteristics of smallholder sesame farmers in the study areas and identify the production practices (varieties, planting methods, fertilizer use, pest management, harvesting, post-harvest handling) employed.
2. Estimate the cost and return structure of sesame production (variable costs, fixed costs, revenue, gross margin, net return per hectare and per household) and analyze the profitability of sesame production.
3. Estimate the technical efficiency of sesame production using stochastic frontier analysis and identify the factors (farmer characteristics, institutional factors, technology adoption) associated with differences in efficiency.
4. Analyze the factors influencing profitability of sesame production (including input use levels, output prices, input prices, farm size, and marketing channel) using multiple regression analysis.
5. Examine the constraints limiting sesame production profitability (including input access, labor availability, credit access, market access, pest and disease pressure, and climate risks) and develop recommendations for policy, extension, and intervention programs.

1.5 Research Questions

This study seeks to answer the following research questions:

1. What are the socio-economic characteristics of smallholder sesame farmers in Benue State, and what production practices do they employ?
2. What is the cost structure, revenue structure, and net profitability (gross margin and net return per hectare) of sesame production in Benue State?
3. What is the level of technical efficiency among sesame farmers in Benue State, and what factors are associated with higher or lower efficiency?
4. What factors (input levels, prices, farm characteristics, farmer characteristics, institutional factors) significantly influence the profitability of sesame production?
5. What are the major constraints limiting the profitability of sesame production, and what strategies can be employed to enhance economic performance?

1.6 Research Hypotheses

Hypothesis One

• Null Hypothesis (H₀₁): Sesame production among smallholder farmers in Benue State is not profitable (net return per hectare is not significantly greater than zero).
• Alternative Hypothesis (H₁₁): Sesame production among smallholder farmers in Benue State is profitable (net return per hectare is significantly greater than zero).

Hypothesis Two

• Null Hypothesis (H₀₂): Adoption of improved sesame varieties has no significant effect on net return per hectare of sesame production in Benue State.
• Alternative Hypothesis (H₁₂): Adoption of improved sesame varieties has a significant positive effect on net return per hectare of sesame production in Benue State.

Hypothesis Three

• Null Hypothesis (H₀₃): There is no significant relationship between access to agricultural extension services and the technical efficiency of sesame production in Benue State.
• Alternative Hypothesis (H₁₃): There is a significant positive relationship between access to agricultural extension services and the technical efficiency of sesame production in Benue State.

Hypothesis Four

• Null Hypothesis (H₀₄): There is no significant relationship between farm size (hectares cultivated) and net return per hectare of sesame production (no economies or diseconomies of scale).
• Alternative Hypothesis (H₁₄): There is a significant relationship between farm size and net return per hectare of sesame production (economies or diseconomies of scale exist).

Hypothesis Five

• Null Hypothesis (H₀₅): There is no significant difference in net return per hectare of sesame production between farmers who sell through cooperative or direct-to-buyer channels and farmers who sell through village assemblers.
• Alternative Hypothesis (H₁₅): Farmers who sell through cooperative or direct-to-buyer channels achieve significantly higher net return per hectare of sesame production than farmers who sell through village assemblers.

1.7 Significance of the Study

This study is significant for multiple stakeholders and purposes. First, for smallholder sesame farmers in Benue State, the findings will provide benchmark economic data on profitability and efficiency, enabling them to assess their own performance and identify areas for improvement. Second, for the Benue State Ministry of Agriculture and the Benue State Agricultural and Rural Development Authority (BNARDA), the study will provide evidence to guide extension programming, input subsidy targeting, and market development interventions for the sesame subsector. Third, for policymakers at state and federal levels, the study will inform decisions about allocating resources to sesame research, extension, and market infrastructure; about prioritizing sesame relative to other crops in agricultural development strategies; and about designing credit and input supply programs. Fourth, for the National Agricultural Seeds Council (NASC) and seed companies, the study will provide evidence on the economic returns to improved sesame varieties, supporting seed multiplication and distribution decisions. Fifth, for development partners and NGOs working in agricultural value chain development in Benue State (e.g., IFAD, World Bank, USAID, FADAMA), the findings will guide intervention design and resource allocation for sesame value chain programs. Sixth, for sesame buying agents, exporters, and processing companies, the study will provide information on production costs, yield determinants, and quality constraints, informing pricing and procurement strategies. Seventh, for financial institutions and microfinance programs, the study will provide data on the profitability of sesame production, supporting credit underwriting decisions. Eighth, for the academic community, the study will contribute to the literature on agricultural production economics in Nigeria, specifically for sesame—an under-researched but economically important crop. Finally, by generating evidence that can enhance sesame profitability and efficiency, the study will contribute indirectly to increasing farm household incomes, reducing poverty, diversifying agricultural production, and generating foreign exchange earnings from sesame exports.

1.8 Scope of the Study

The geographical scope of this study is limited to selected sesame-producing Local Government Areas (LGAs) in Benue State, Nigeria. Based on preliminary information from the Benue State Ministry of Agriculture, the study will focus on LGAs with significant sesame production, including but not limited to: Gwer West, Guma, Makurdi, Tarka, Buruku, and possibly others depending on preliminary field verification. These LGAs are located in the northern and central parts of Benue State, where the Guinea savannah agroecological zone provides suitable conditions for sesame cultivation. The thematic scope focuses specifically on the economic analysis of sesame production, including: cost of production (variable and fixed costs); revenue and profitability (gross margin, net return); technical efficiency (using stochastic frontier analysis); factors influencing profitability (using multiple regression); production constraints; and marketing channel analysis. The study examines both improved and local sesame varieties, but does not extend to sesame processing (oil extraction) or sesame marketing beyond the farm-gate and local market levels. The respondent scope includes smallholder sesame farmers (cultivating ≤5 hectares of sesame) in the selected LGAs. Key informants (extension agents, sesame buying agents, cooperative leaders, BNARDA officials) are also included for qualitative data collection. The temporal scope covers the period 2019-2025, with primary data collected between 2024 and 2025, focusing on the most recent completed production season (typically the 2024 rainy season for rain-fed sesame, or 2024-2025 dry season where irrigation is used).

1.9 Limitation of the Study

Several limitations inherent in this study should be acknowledged transparently. First, the study relies primarily on cross-sectional survey data collected from a single production season, which captures economic performance in one season but may not be representative of typical performance if that season was atypical (e.g., unusually good or bad rainfall, abnormal pest pressure, unusual price movements). Second, the study focuses on selected LGAs within Benue State, so findings may not be generalizable to other sesame-producing areas within Benue (e.g., southern LGAs with different agroecological conditions) or to sesame farmers in other states. Third, the study’s reliance on farmer recall for data on input use, output, costs, and prices is subject to recall bias and measurement error; where possible, the study will employ multiple recall aids and cross-check responses, but administrative records are unavailable for most smallholder farmers. Fourth, social desirability bias may affect responses about input use (overstating use of improved practices) and profitability (overstating income). Fifth, the study values family labor at market wage rates for calculating net returns, but market wage rates may not accurately reflect the opportunity cost of family labor (especially if off-farm employment is limited). Sixth, the study does not include a longitudinal component, so it cannot assess inter-annual variability in profitability or the sustainability of sesame production over time. Seventh, the stochastic frontier analysis used to estimate technical efficiency assumes a particular functional form (e.g., Cobb-Douglas or Translog) and distributional assumptions for the inefficiency term; results may be sensitive to these assumptions. Eighth, the study does not include soil sampling, so soil fertility variation (which affects yield and thus profitability) is captured only through farmer reports and location dummy variables. Ninth, the sample size, while statistically adequate for planned analyses, may limit the ability to detect small effects or to conduct highly disaggregated subgroup analyses (e.g., separate analysis for each LGA with small cell sizes). Tenth, the study does not include a detailed analysis of post-harvest losses (due to threshing inefficiency, inadequate drying, storage pests), which could affect realized profitability. Eleventh, security conditions in some parts of Benue State (inter-communal conflicts, farmer-herder conflicts, banditry) may affect data collection access and respondent willingness to participate. Twelfth, the study focuses on sesame production (farm-level economics) and does not include a full value chain analysis examining processing, wholesaling, or export margins. Despite these limitations, the study will employ rigorous sampling methods, validated survey instruments, appropriate analytical techniques (including diagnostic tests for functional form assumptions, sensitivity analyses, and robustness checks), and transparent reporting to maximize the credibility and utility of its findings for policy and practice.

1.10 Definition of Terms

Sesame (Sesamum indicum L.): An annual oilseed crop cultivated for its seeds, which contain 40-50% high-quality oil (rich in unsaturated fatty acids) and 30-40% protein. Sesame seeds are used for oil extraction, direct consumption (whole seeds in confectionery and bakery products), and as a source of protein-rich seed cake for animal feed.

Economic Analysis: The systematic examination of the relationships between inputs (land, labor, capital, materials) and outputs (sesame seed yield, quality, revenue) to assess profitability, efficiency, and the factors that influence economic performance. In this study, economic analysis includes cost-benefit analysis, production function estimation, and efficiency measurement.

Smallholder Farmer: A farmer cultivating a relatively small area of land, typically using family labor as the primary labor source, with limited use of mechanization and purchased inputs. For this study, smallholder sesame farmers are defined as those cultivating ≤5 hectares of sesame in the reference season.

Profitability: The excess of revenue over costs in sesame production. This study measures profitability through two metrics: (a) gross margin (revenue minus variable costs, where family labor is excluded from costs), which represents the return to fixed factors (land, family labor, management); and (b) net return (revenue minus total costs including valued family labor and allocated fixed costs), which represents economic profit.

Cost of Production: The total expenditure (cash and imputed) incurred in producing sesame, including: variable costs (seed, fertilizer, pesticides, herbicides, hired labor, transport) and fixed costs (depreciation of equipment and tools, land rental payments, imputed family labor valued at market wage rate).

Gross Margin: Revenue from sesame sales (plus imputed value of home consumption) minus total variable costs (costs that vary with output level). Gross margin does not include fixed costs or imputed family labor costs; it represents the contribution of sesame production to covering fixed costs and generating returns to family labor and management.

Net Return (Profit): Revenue from sesame sales (plus imputed value of home consumption) minus total costs (variable costs plus fixed costs plus imputed family labor). Positive net return indicates that sesame production is economically profitable; negative net return indicates that total costs exceed revenue.

Technical Efficiency: The ability of a farmer to produce maximum possible output from a given set of inputs (output-oriented technical efficiency) or to use minimum possible inputs to produce a given output (input-oriented technical efficiency). Technical efficiency scores range from 0 to 1; a score of 1 indicates perfect efficiency (operating on the production frontier), while scores below 1 indicate inefficiency (operating below the frontier).

Stochastic Frontier Analysis (SFA): An econometric method for estimating technical efficiency that distinguishes between random error (statistical noise, measurement error, luck) and inefficiency. The production frontier (maximum possible output for given inputs) is estimated, and each farm’s distance from the frontier (the inefficiency term) is calculated.

Allocative Efficiency: The ability of a farmer to use inputs in optimal proportions given input prices and output price (i.e., minimizing cost for a given output or maximizing output for a given cost). Allocative efficiency requires that the marginal rate of technical substitution between inputs equals the input price ratio.

Economic Efficiency: The product of technical efficiency and allocative efficiency; the ability to produce a given output at minimum cost (or to maximize profit given output price and input prices). Economic efficiency is the most comprehensive measure of farm performance.

Production Function: A mathematical relationship describing the maximum output obtainable from given quantities of inputs. In this study, a Cobb-Douglas or Translog production function will be estimated for sesame, with output (sesame seed kg) as a function of inputs (land, labor, seed, fertilizer, etc.).

Benue State Agricultural and Rural Development Authority (BNARDA): The state government agency responsible for agricultural extension services, technology dissemination, and farmer training in Benue State. BNARDA is a key source of information and support for sesame farmers.

Improved Sesame Variety: Sesame cultivars developed through formal plant breeding programs that possess superior characteristics relative to local landraces, including higher yield potential, earlier maturity, improved oil content, better pest and disease resistance, shattering resistance (reduced seed loss at harvest), and more uniform seed color (desired by export markets). Examples include E8, NCRIBEN-01M, NCRIBEN-02L, and other varieties released by NCRI.

Saved Seed (Farmer-Saved Sesame Seed): Seed retained by farmers from their own previous harvest for use as planting material in the next season. Saved seed from local varieties may have lower germination rates, lower varietal purity, and lower yield potential compared to certified improved seed.

Shattering: The tendency of sesame capsules to split open and release seeds when mature, resulting in seed loss if harvesting is not done carefully or timely. Shattering resistance is an important trait of improved sesame varieties.

Sesame Webworm (Antigastra catalaunalis): A major insect pest of sesame that feeds on leaves, flowers, and capsules, causing defoliation, flower drop, and direct damage to developing seeds. Severe infestation can cause substantial yield losses.

Phyllody Disease: A phytoplasma disease of sesame that causes flower malformation (conversion of flowers into leaf-like structures), sterility, and yield loss. Phyllody is transmitted by leafhoppers and is a significant constraint in some producing areas.

Farm Gate Price: The price received by farmers for sesame sold at the farm (i.e., the price before transport, handling, and intermediary margins). Farm gate prices are typically lower than prices at periodic markets or company buying points, reflecting the buyer’s costs of collection and transport.

Village Assembler (Middleman): A local buyer who purchases small quantities of sesame directly from individual farmers at the farm gate, aggregates them into larger lots, and sells to larger traders, buying agents, or processing companies. Village assemblers play a dominant role in sesame marketing in Benue State.

Cooperative (Sesame Farmers Cooperative): A formal or informal association of sesame farmers who pool resources, share information, aggregate output for collective marketing, and sometimes access credit or inputs collectively. Cooperative membership may enhance farmers’ bargaining power and market access.