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Technology adoption and farm performance in sub-Saharan Africa: evidence from Mozambique and Ghana
(2025) Asravor, Jacob; Zeller, Manfred
Increasing the productivity of agriculture in sub-Saharan Africa (SSA) is fundamental to achieving many of the Sustainable Development Goals (SDGs) in the region and, by extension, in the world. Given its importance to rural livelihoods and national economies in SSA, productivity growth in this crucial sector has the potential to stimulate broad-based poverty reduction (SGD 1) and further address the persistent food insecurity and malnutrition challenges (SDG 2) faced by the region. However, despite its potential for growth and importance to the region, productivity growth in agriculture has either stagnated or declined in SSA over the years. Efforts to tackle this persistent challenge have been focused on the promotion of improved technological packages and modern farming practices in various parts of the region. Nonetheless, adoption has mostly remained sluggish across SSA, stressing the continuing need for a deeper understanding of the underlying barriers to sustained adoption, as well as the effects of adopted technologies and farming practices on farm performance, particularly in terms of technical efficiency and technological gains.
The smallholder farming contexts of Mozambique and Ghana offer distinct cases for gaining useful insights into the underlying barriers to sustained adoption of modern technologies and farming practices, as well as their effects on farm performance. Specifically, despite ongoing efforts by the Mozambican government and development partners to promote sustainable intensification practices, such as integrated soil fertility management (ISFM) practices (including mineral fertilizer, improved seeds and depending on the location, organic inputs such as manure and compost), adoption remains low among farm households. As a result, resource-poor farmers often resort to unsustainable land use practices, such as shifting cultivation, slash-and-burn agriculture, deforestation and forest degradation, along with low-cost agronomic practices like crop rotation, crop residue retention and intercropping to safeguard soil fertility. However, evidence is scarcely available on the underlying barriers to sustained adoption of promoted ISFM practices, along with the technological and technical efficiency gains associated with integrating improved versus recycled seeds with agronomic practices in Mozambique.
Furthermore, one of the key challenges to technology adoption, as well as to farm performance and the long-term sustainability of agriculture, is the issue of aging farming population. This issue is particularly pressing in Ghana, where, in addition to the growing disinterest of young people in farming and an estimated life expectancy ranging from 55 – 65 years, the average age of farmers is reported to be 55. Given that the majority (73.5%) of Ghana’s population is below the age of 36, an improved understanding of how farm operators’ age influences their managerial performance and technology adoption is crucial for shaping evidence-informed policies aimed at attracting, retaining and leveraging this demographic dividend within the Ghanaian agricultural sector. From the foregoing, this thesis has three key objectives: (1) to explore context-specific evidence on the systemic barriers to sustained adoption of integrated soil fertility management (ISFM) practices by Mozambican smallholder farmers; (2) to examine the technological and technical efficiency gains associated with integrating improved versus recycled seeds with agronomic practices such as crop rotation, intercropping and crop residue management by Mozambican smallholder farmers; and (3) to assess how the age of farm operators – disaggregated into the youth, middle-aged and aged – influences their managerial performance and farm technology adoption in Ghana.
The objectives of this thesis were achieved using data from both primary and secondary sources. Relying on mixed-methods research design, qualitative data were drawn using key informant interviews (KIIs) and focus group discussions (FGDs), and quantitative data via a household survey in the Central and Northern zones of Mozambique. These primary data were used to address the first and second objectives of the thesis. Overall, 32 qualitative interviews, consisting of 8 FGDs, 5 medium- and large-scale farmer KIIs and 19 expert KIIs were conducted in Mozambique. This was followed by a household survey which was conducted in the Central and Northern zones of Mozambique, involving 607 farming households who were selected through a multi-stage sampling technique. Both datasets were collected in 2022. To address the third objective of the thesis, secondary data from two nationally representative surveys in Ghana were used. These include all seven waves of the Ghana Living Standards Survey (GLSS) which were conducted from 1987/88 – 2016/17 and the two waves of the Ghana Socio-economic Panel Survey (GSPS) conducted between 2009/10 and 2014/15. While the GLSS was implemented using a repeated cross-sectional design, the GSPS followed a panel design. Overall, 24,596 farm households across Ghana were included in the sample for analysis.
This thesis is organized into five chapters. Chapter 1 introduces the research topic by providing a general overview of the study within the global and sub-Saharan African contexts, followed by background information on agriculture and technology adoption in both Mozambique and Ghana. Chapter 2 explores the systemic barriers that continue to impede the sustained uptake of ISFM practices among Mozambican smallholder farmers. Chapter 3 evaluates the technological and technical efficiency gains associated with existing farmer practices of integrating improved versus recycled seeds with agronomic practices in Mozambique. Chapter 4 examines the relationship between farm operators’ age, technology adoption and managerial performance in Ghana. Finally, chapter 5 presents the conclusion of the thesis, outlines its limitations and makes recommendations for policy and future studies.
Chapter 2 relies on mixed-methods research design to explore the systemic barriers to sustained adoption of ISFM practices among Mozambican resource-poor farmers. Complementing content analysis of qualitative data with descriptive analysis of data from a household survey, the findings indicate that whereas Mozambican smallholder farmers have generally recognized the compelling need for ISFM practices in high-value crop production systems such as vegetables, cotton, sugarcane and tobacco, they are reluctant to make similar investments in food crops. Instead, they adopt low-cost agronomic practices such as crop residue management, intercropping, crop rotation and shifting cultivation to safeguard soil fertility in food crop systems. Evidence further shows that the use of improved seeds, mineral fertilizers and depending on the location, external organic inputs such as manure and compost, is more prevalent among three groups of Mozambican smallholder farmers: independent vegetable producers, farmers participating in contract farming schemes and those residing in districts bordering Malawi, Zambia and Zimbabwe. Additionally, despite expressing strong willingness to invest in these inputs, farmers’ access to and use of these inputs are hindered by a complex set of systemic barriers, including unfavorable market conditions which limit profitability and intensify risk; institutional limitations such as credit constraints and human capital limitations; liquidity constraints; challenges associated with key ISFM components; an existing culture of dependency shaped by past experiences of farmers with free inputs; and entrenched perceptions among both farmers and professionals that Mozambican soils are inherently “fertile” or “virgins” and “fertilizers destroy the soil”. Given these findings, the study recommends that interventions aiming to promote sustainable land use practices like ISFM in land-abundant contexts of SSA like Mozambique, should prioritize addressing these systemic barriers to ensure sustained adoption of these practices. For instance, to raise productivity in food crop systems, agrarian interventions should adopt a holistic value chain approach which goes beyond the production phase to strengthen other critical segments of the value chain, such as extending agro-dealer networks to major production areas, as well as enhancing access of smallholder farmers to output markets that offer stable and fair prices. Again, there is the urgent need to intensify education and raise awareness among both farmers and professionals to dispel the widespread misconception that fertilizers damage the soil and on the need for farmers to implement ISFM as a package rather than in isolation. Addressing these systemic constraints holds an enormous prospect for fostering the sustained uptake of sustainable intensification practices like ISFM in Mozambique.
Drawing on the findings from chapter 2, which indicates that Mozambican smallholder farmers seldom invest in purchased inputs for food crops, chapter 3 utilizes the same data to assess the technological and technical efficiency gains associated with existing farmer practices of integrating improved versus recycled seeds with agronomic practices, including crop rotation, intercropping and crop residue management in food crop systems. Relying on an endogeneity-corrected stochastic frontier and metafrontier functions to analyze the quantitative data, results from this first-stage analysis were contextualized and reinforced with evidence from the qualitative data. The findings suggest that farm households who integrated improved seeds with agronomic practices achieve a modest technological advantage (4%) relative to their peers who integrated recycled seeds with these same practices. Nonetheless, the results reveal no significant difference in technical efficiency between both groups. Instead, farm households in both groups performed these agronomic practices so poorly, such that each group could expand its total farm production by more than 50% simply by implementing these existing agronomic practices more efficiently. Consequently, the greatest potential for raising farm output in food crop systems in Mozambique lies in the capacity of resource-poor households to effectively implement these existing agronomic practices. Based on the findings, it is recommended that programs aiming to boost productivity in food crop systems in Mozambique should prioritize building the capacity of farm households to enable them implement these agronomic practices more efficiently. Encouraging resource-poor farmers to strictly adhere to recommended agronomic protocols, such as selecting the right crop mixes for intercropping and rotation, retaining crop residues on the field and using inoculants to boost nitrogen fixation in legumes can considerably enhance soil fertility and support productivity in subsequent crops.
Given the increasingly aging farming population in Ghana and the urgent need for evidence-informed policies aimed at attracting and retaining the country’s growing youth population in agriculture, chapter 4 of the thesis relies on a nationally representative data from the GLSS and GSPS to evaluate how the age of resource-poor farmers influence their farm-level decision-making in terms of technology adoption and managerial performance. Drawing on a three-decade dataset from cereal-producing households and guided by the definitions of youth provided by the African Youth Charter and Ghana’s National Youth Policy, farm households were categorized into three age-based groups: youth (15–35 years), middle-aged (36–59 years) and aged (60 years and above). The findings indicate that farm operator age does not have a statistically significant effect on the type or level of agricultural technology adopted by farming households in Ghana. This finding remains robust even when the analysis is disaggregated by cereal type (i.e., maize, rice, millet and sorghum). However, the findings reveal marked differences in managerial performance between younger and older farmers, with the youth exhibiting greater managerial proficiency relative to their older peers. These findings suggest that when offered equal access to productive resources, younger farmers are better equipped to drive agricultural productivity growth in Ghana, thereby significantly contributing to the sector’s growth in the country. The study recommends for policymakers to pursue youth-focused agrarian initiatives that ensure easy access of the youth to productive resources such as land, credit and improved technologies, aimed at enabling younger farmers to leverage their potential in driving agricultural productivity gains.
Overall, the findings of this thesis bring to the fore the existing systemic barriers that continue to obstruct smallholder investment decisions in sustainable land use practices like ISFM in land-abundant contexts like Mozambique and further underscore the urgent need for policy measures aimed at addressing them. It further stresses that the greatest potential for sustainably raising farm performance in low-input food crop systems in Mozambique lies in the ability of resource-poor farmers to implement these low-cost agronomic practices more efficiently. Finally, the findings highlight the need to focus on enhancing the managerial skillsets of farm operators across all age groups, especially the younger ones, rather than just concentrating on technological advancements.
Interactive effects of feed particle size, calcium, and exogenous phytase on gastrointestinal phytate degradation and related traits in broiler chickens
(2025) Wolfrum, Stephanie; Rodehutscord, Markus
Phosphorus (P) is an essential element in maintaining the physiological mechanisms of poultry, making an adequate dietary P supply crucial. In plant-based feed ingredients commonly used in poultry nutrition, the primary form of P is phytate, any salt of phytic acid (InsP6). Enzymes that hydrolyze InsP6, such as phytases and phosphatases, are needed to release P from InsP6 for digestion and absorption. The extent to which P is released depends on the limited and variable endogenous enzyme capacity of poultry. Consequently, diets are often supplemented with costly mineral P sources derived from finite global rock phosphates to meet P requirements. Any unabsorbed P is excreted and contributes to environmental impacts. Incorporating exogenous phytases into poultry diets enhances the P release from InsP6, thereby enabling reduced use of mineral P supplements. To further improve P utilization and completely replace supplemental mineral P, it is essential to understand the effects on phytase efficacy, both single and interactive. Therefore, three studies were conducted to gain deeper insight into the InsP6 degradation and related characteristics along the digestive tract of broiler chickens, as influenced by dietary ingredients and their physical properties. Using coarsely ground feed particles in broiler diets improves digestive tract development and nutrient utilization. Coarse particles may therefore be beneficial for InsP6 degradation. Moreover, dietary coarse particles might mitigate the inhibitory effects of high dietary calcium (Ca) concentrations by lowering the pH in the digestive tract. The first study aimed to investigate the single and interactive effects of feed particle size and Ca concentration in the absence and presence of exogenous phytase on InsP6 degradation, prececal digestibility of P, Ca, and amino acids (AA), and retention of P, Ca, and nitrogen (N). Ross 308 broiler chickens received experimental diets from day 7 to 22/23 of life. Experimental diets differed in feed particle size (fine and coarse; 222 and 309 μm), Ca concentration (low and high; 4.9 and 7.2 g/kg), and phytase supplementation (0 and 1,000 FTU/kg). Prececal InsP6 disappearance increased with coarse particle size without phytase supplementation. Supplemented phytase removed such differences. Coarse particles were associated with higher gizzard weights and lower gizzard content pH compared to fine particles, whereas high dietary Ca concentration increased the pH of the gizzard content. Thus, the antinutritive effects of the higher dietary Ca concentration were not mitigated by using coarse feed particles, resulting in a reduction in prececal InsP6 disappearance and digestibility of P and most of the AA. Prececal AA digestibility increased with dietary coarse particles compared to fine particles. In the presence of phytase, high dietary Ca enhanced InsP6 disappearance in the crop. The first study found that dietary coarsely ground feed particles without supplemented phytase increased prececal InsP6 disappearance, but phytase supplementation compensated for this particle size effect. Accordingly, the objective of the second study was to determine the single and interactive effects of feed particle size and phytase level. Effects on growth performance, prececal InsP6 disappearance, prececal digestibility of P and Ca, and tibia characteristics were examined. From day 10 to 38 of life, Ross 308 broilers were fed experimental diets containing fine and coarse feed particles (434 and 729 μm) and without and with phytase supplementation (300, 600, and 1,200 FTU/kg). Particle size and phytase did not interact significantly concerning any measured trait. Contrary to expectations, finely ground feed particles increased prececal InsP6 disappearance and P digestibility, suggesting coarse grinding of rapeseed meal may not benefit birds. Growth performance, prececal InsP6 disappearance and related P digestibility, as well as tibia ash and breaking strength, were increased by phytase supplementation. This indicated that diets met the bird’s P requirement at the given total P level and 1,200 FTU phytase/kg, allowing the renouncement of feed phosphate in the grower and finisher phases without adverse effects on performance and bones. Based on a previous study that found a linear relationship between the dietary InsP6 concentration and the prececal InsP6 disappearance caused by supplemented phytase, the third study aimed to verify this indication of a constant prececal InsP6 disappearance per unit of supplemented phytase. This suggested that the efficiency of supplemented phytase was not affected by dietary InsP6 concentration. The study investigated the effects of dietary InsP6 concentration and phytase supplementation on gastrointestinal InsP6 degradation, prececal digestibility of P, AA, and Ca, and N-corrected metabolizable energy (MEN) in broiler chickens. Ross 308 broilers were provided with diets from day 14 to 22/23 of life. Dietary InsP6 was increased by substituting corn starch with a mixture of 50 % soybean meal, 20 % rapeseed meal, 20 % sunflower meal, and 10 % rice bran (oilseed meal-rice bran levels (ORL)). Experimental diets included four dietary InsP6-P concentrations (ORL1, ORL2, ORL3, and ORL4) and three phytase levels (500, 1,500, and 3,000 FTU/kg). Feed ingredient exchange led to additional diet alterations beyond changes in InsP6 concentration, including variations in P, crude protein, Ca, and fiber concentrations. Increasing ORL decreased the InsP6 disappearance in the crop. Prececal InsP6 disappearance and P digestibility decreased linearly with increasing ORL at 500 FTU/kg, whereas ileal myo-inositol concentration was unaffected. This indicated that the supplemented phytase was the limiting factor for the complete dephosphorylation of InsP6 to myo-inositol. At 1,500 and 3,000 FTU/kg, prececal InsP6 disappearance and P digestibility differed hardly among ORL but decreased with increasing ORL. A non-linear relationship was found at 500 FTU/kg when prececal InsP6 disappearance or ileal myo-inositol concentration relative to FTU was regressed against dietary InsP6. Such relationships were linear at 1,500 and 3,000 FTU/kg, suggesting that the efficiency of supplemented phytase to fully hydrolyze InsP6 to myo-inositol at 1,500 FTU/kg or higher was impaired by phytase level but not ORL. The cecal InsP6 concentration increased with ORL and decreased with phytase. Increasing ORL decreased the prececal digestibility of all AA (except cysteine) and MEN. In conclusion, conflicting effects on InsP6 degradation concerning feed particle size and its effects on endogenous and supplemented enzymes were found. This suggests that using coarsely ground particles in the feed may not be equally effective for all ingredients. Rapeseed meal is potentially less suitable than wheat or corn in coarsely ground form. Regardless of phytase level, coarse feed particles increased prececal AA digestibility. Due to the inconsistent results and a lack of studies regarding feed particle size effects on InsP6 degradation and prececal AA digestibility, further research is needed. The antinutritive effects of dietary Ca on InsP6 degradation and prececal AA digestibility could not be compensated for by using coarse feed particles. To maximize nutrient utilization, feed particle size should be adapted to the respective raw material, and dietary Ca should be as low as possible without risking a deficit, combined with phytase. Supplemented phytase at 1,500 FTU/kg or higher does not impair InsP6 degradation and prececal AA digestibility in response to increasing ORL. Thus, adjusting the phytase level to increased dietary InsP6 concentrations was not necessary under the conditions of this study, and further research is necessary.
Buckwheat in Germany: The effect of variety and sowing date on agronomic traits
(2025) Grimes, Samantha J.; Afzal, Muhammad; Tako, Rea; Hahn, Volker; Graeff‐Hönninger, Simone; Longin, C. Friedrich H.; Grimes, Samantha J.; Department of Agronomy, Institute of Crop Science, University of Hohenheim, Stuttgart, Germany; Afzal, Muhammad; State Plant Breeding Institute, University of Hohenheim, Stuttgart, Germany; Tako, Rea; State Plant Breeding Institute, University of Hohenheim, Stuttgart, Germany; Hahn, Volker; State Plant Breeding Institute, University of Hohenheim, Stuttgart, Germany; Graeff‐Hönninger, Simone; Department of Agronomy, Institute of Crop Science, University of Hohenheim, Stuttgart, Germany; Longin, C. Friedrich H.; State Plant Breeding Institute, University of Hohenheim, Stuttgart, Germany
Buckwheat (Fagopyrum esculentum Moench) requires minimal agrochemical inputs and delivers grains with a high nutritional profile—the perfect prerequisites for future sustainable farming. However, it is currently consumed and produced in only a few countries. The aim of this study was to investigate the potential to successfully grow buckwheat in Germany and to elaborate first insights for local breeding. Therefore, a total of 33 buckwheat varieties were tested across three locations, 3 years, and two different sowing dates. The average yield was 2.3 t ha −1 , ranging from 1.4 to 3.1 t ha −1 across varieties. Similar yields were observed for both early and late sowing dates, and across all tested varieties. All but two of the very late‐maturing common buckwheat varieties could be safely harvested in all locations also on the late sowing date. Key prerequisites to establish local breeding were met, including large genetic variation and high heritability for important agronomic traits. In summary, this study highlights the importance of variety selection and targeted breeding focusing on early‐maturing buckwheat varieties, paving the way for potential double‐cropping systems in Germany that use buckwheat as a second crop and significantly enhance its profitability for farmers.
Impact of soil improvers on soil health: A data mining approach to support sustainable agriculture across the EU
(2025) Nolfi, Lorenzo; Bindo, Arianna; Di Gregorio, Luciana; Costanzo, Manuela; Caldara, Marina; Tabacchioni, Silvia; Visca, Andrea; Salo, Tapio; Bauerle, Andrea; Hansen, Veronika; Bernini, Roberta; Varese, Giovanna Cristina; Manikas, Ioannis; Marmiroli, Nelson; Palojärvi, Ansa; Bevivino, Annamaria
Soil health is crucial for the sustainability of agricultural practices and ecosystem resilience. Using a data mining approach, this study aims to explore emerging themes related to the impact of soil improvers on soil health by analyzing results from various EU-funded agricultural projects, with the final goal of identifying the key factors driving the effectiveness of soil amendments. By integrating data mining and text analysis, the study extracts, aggregates, and visualizes insights, providing a comprehensive overview of innovative strategies to enhance soil fertility and promote ecological balance. This integrated analytical framework offers a nuanced understanding of the conceptual landscape surrounding soil health in EU projects, highlighting the multifaceted roles of organic amendments and microbial solutions. Our findings underscore the critical link between organic amendments and soil health, highlighting their potential as strategic tools for achieving more sustainable agricultural systems. These findings provide a basis for refining soil management strategies in agriculture and support the development of evidence-based policies aimed at improving soil health and fostering ecological balance across Europe.
Conquering knowledge exchange barriers with age differences: a stress appraisal perspective on the consequences of upward social comparisons
(2025) Rinker, Laura; Fasbender, Ulrike; Gerpott, Fabiola H.; Burmeister, Anne
Knowledge exchange is crucial for organizations, but interpersonal dynamics can entail stress, affecting whether and how knowledge flows. Integrating social comparison and stress appraisal research, we propose that upward social comparison can be appraised as challenging or hindering. We suggest a dual pathway model involving an approach pathway via challenge appraisal and an avoidance pathway via hindrance appraisal with consequences on three knowledge exchange behaviours (i.e., knowledge sharing, knowledge seeking and knowledge hiding). Additionally, we examine age differences (vs. no age differences) to the comparison target as a buffer. We conducted two preregistered experimental online studies with employees (NStudy 1 = 206, NStudy 2 = 414), utilizing a 2 (social comparison; upward, lateral) × 3 (target age; younger, same‐age, older) between‐subject design. Participants received bogus task performance feedback (Study 1: cognitive ability test; Study 2: typing ability test). Both studies show that upward social comparison (but not other social comparison directions) fosters knowledge hiding via hindrance appraisal. This effect is weakened by an age difference (vs. no age difference) to the comparison target. However, our results do not support the approach pathway via challenge appraisal. Our research highlights social pitfalls in knowledge exchange and emphasizes the benefits of age differences between colleagues.