Rwanda Journal of Agricultural Sciences

Editorial Board Message

Srinivasan R. Thoppe — 2025-05-16

No abstract

Assessment of the relationship between soil reaction, organic carbon, and other soil chemical attributes in potato farms in Rwanda

A. Turamyenyirijuru — 2025-05-16

Soil reaction (pH) and organic carbon (OC) emerged as governors and more indicative of soil properties and fertility. They govern various soil properties and processes in the soil. Despite potato yield potential, its yield remains low in Rwanda due to the decline in soil fertility and ineffective use of fertilizers. Nutrient deficiency and imbalance are major constraints to the productivity and sustainability of soils. This study evaluated the relationship between soil pH as well as OC with other chemical soil properties (N, P, Ca, Mg, K, CEC, S, Cu, Fe, Mn and Zn), in potato farms of Birunga and Buberuka highlands agro-ecological zones of Rwanda. Twelve composite samples, each replicated three times, were collected across twelve farms representative of potato fields in each location. Descriptive statistical parameters were calculated, using SAS Version 9.2 statistical software, for the selected soil attributes and their mean values varied from low to medium. The significance of correlation was determined by Pearson’s correlation coefficient analysis. There was very high and significant positive correlation (p < 0.001) between OC as well as pH and all selected soil attributes. Factor analysis extracted two factors from observed variables and ratings of factor loadings were qualified strong (> 0.75) and moderate (0.50 to 0.75) at each site. The two latent variables were related to either inherent or dynamic soil properties. The results revealed pH and OC as shapers of soil chemical properties and fertility. There is a need for them to be the pillars of any optional technology developed to enhance soil fertility and productivity in the research areas. Adoption of site-specific nutrient management practices is recommended for rational soil nutrients management and land utilization.

Oil absorption and moisture loss of French fries and crisps from selected potato (Solanum tuberosum l.) cultivars grown in Rwanda

V. Ndungutse — 2025-05-16

This study aimed to investigate oil absorption and moisture content of potato French fries and crisps. The analysis consisted of the moisture content of raw and fried potatoes as well as the internal, surface, and total oil of French fries and crisps immediately after frying and cooling. Collected data were subjected to Analysis of variance (ANOVA) using SAS version 9.2 and means were separated by Tukey’s test at a 5% level of significance. Moisture content was 74.9 -76.89% for raw French fries, 73.47-76.40% for raw crisps, 32.23- 41.58% for French fries, and 1.73-2.02% for crisps. Immediately after frying oil content for French fries was 3.77-4.21% for internal oil, 3.07-6.85% for surface oil, and 6.84-10.90% for total oil, while for crisps it was 4.95-6.93 internal oil, 7.65-9.63% surface oil and 12.7-16.49% for total oil. After cooling internal oil increased dramatically, for French fries it was 8.49-11.67% for internal oil, 3.48-7.50% for surface oil, and 1.97-18.48% for total oil, while for crisps it was 22.44-28.27% for internal oil, 11.05-14.57% for surface oil and 33.49-42.84% for total oil. Potatoes with high moisture content absorb more oil resulting to soggy products. The high amount of oil is unhealthy due to its potential for rapid weight gain.

Factors influencing farmers’ motivation to use dietary practices in Rwanda

C. Bigirimana — 2025-05-16

Worldwide and especially in Sub-Saharan Africa, agriculture remains central to the global fight to end extreme poverty and hunger. In Rwanda, agriculture should lead to food security but also provide an adequate livelihood and income for rural people, focusing on their ability to feed themselves. However, despite having such considerable potential and the efforts made by the Government of Rwanda, the farming community is still food insecure and malnutrition remains one of the serious health and economic challenges facing smallholder farmers and the most important public health concern. Up to now, there are limited studies that have evaluated perceptions and attitudes toward healthy eating and balanced dietary intake among rural Rwandan farming communities. This research project aims to evaluate the food security situation and to assess the farming communities’ attitudes and perceptions toward a balanced diet in Rwanda. The study was carried out in the Rubavu District in the Western Province of Rwanda. Both quantitative and qualitative methods were employed. Primary data were collected from 300 smallholder farming communities randomly selected using structured questionnaires. Besides, the site visit and key informants’ interviews were conducted. Data were analyzed using descriptive statistics to describe the socio-economic characteristics of small farming households. The Tobit Model was employed to analyze the factors that influence farmers’ motivation to use appropriate feeding practices in Rwanda. Fruits and vegetables (6%), animal products (9.3%, cereals (23,3%), and roots and tubers (28.3%) were the main dietary practices in Rubavu district. Age, education level, and household health status are factors associated with dietary practices in the study areas. The study’s findings will contribute to the improvement of food and nutrition policy in Rwanda and the development of appropriate interventions in the community.

Factors influencing smallholder farmers’ decision to participate in cassava production in Ruhango district

F. Mushimiyimana — 2025-05-16

Household food insecurity and undernutrition remain a huge challenge in Rwanda, partly due to low agricultural productivity. The study assessed factors influencing smallholder farmers ’s decision to participate in cassava production in Ruhango district. Descriptive statistics and a Logit model using PSM (Propensity Score Matching) have been used for analysis data. Using the Kernel Method, the results indicated that a cooperative member could increase her/his farm production by 4206.22 kg per hectare per year. The results showed that the majority of cassava farmers are relatively old persons. The study also found that there were capital constraints to join cassava cooperatives. This reflects the need to encourage youth to join cooperatives and also facilitate them to acquire the required capital. Moreover, the study revealed that members benefited from several opportunities including; access credits and extension services, higher land size, and higher cassava production through cooperatives. Despite several factors that may hinder farmers from joining cassava cooperatives, relevant institutions should address key concerns that include the need to organize farmers into cooperatives to improve smallholder farming production. This implies that farmers must be facilitated to meet membership requirements and different capital required to join cooperatives. It is therefore interesting to explore the paths in the cassava cooperatives. Such institutions should be attractive and guarantee economic benefits to their membe

Evaluation of nutrient content in cooking banana peels as food and food additives

C. Musabwayire — 2025-05-16

Bananas are essential perennial crops in Rwanda, playing a significant role in the economy and food security. Cooking bananas (Musana acuminata) are particularly valued for their culinary versatility. Despite the nutritional richness of banana peels, they are often discarded as waste. This study aimed to investigate the nutritional composition of banana peels and explore their potential applications as food and food additives. Two varieties, Injagi and Inshakara (Musa acuminata), were selected for sampling. A total of 12 samples were analyzed, derived from four initial samples, each processed in triplicate. Laboratory analyses were carried out on samples collected at ZEAN Ltd, located in Rugera Sector, Nyabihu District, Rwanda, focusing on two cooking banana varieties: Injagi and Inshakara (Musana acuminata). The methodology involved analyzing mineral elements and the proximate composition of both cooked and uncooked banana peels. Results revealed that cooking banana peels increased levels of zinc and potassium while reducing copper and phosphorus concentrations. Conversely, uncooked banana peels exhibited higher levels of copper and phosphorus. Regarding proximate composition, cooking enhanced fat, carbohydrate, energy, and dietary fiber content but reduced moisture and protein levels.
The findings highlight the untapped nutritional potential of banana peels for human and animal consumption, supporting zero-waste initiatives and food security efforts. Their use aligns with circular economic principles by addressing malnutrition, poverty, and environmental pollution. The study advocates raising awareness about the advantages of utilizing banana peels in diets or as additives in food products. By extracting nutrients or consuming them directly, individuals can reduce waste and contribute to environmental conservation.

Determinants of travertine adoption: Evidence from smallholder farmers in Rwanda

J.D. Niyomugabo — 2025-05-16

Rwanda's agricultural productivity is severely constrained by soil acidity, yet smallholder farmers face significant barriers in adopting sustainable soil amendments like travertine due to different household-based constraints. This study aimed to evaluate farm household-based factors affecting agricultural travertine adoption among smallholder farmers. This study was conducted in the Congo Nile divider, Central and Eastern agroecological zones of Rwanda. Two-stage cluster and systematic sampling techniques were performed to select 17 districts where 15 cells per district and 2,474 respondents from 250,000 farmers’ communities were selected respectively. Descriptive statistics and logistic regression analysis were performed via STATA. Results revealed that Agroecological Zone (21.03%), Land Tenure (-20.97%), Agricultural Training (17.28%), and Access to Credit (12.13%) affect travertine adoption. Moreover, agroecological zones and agricultural training and access to credit were statistically significant at (p< 0.05). Moreover, extension services and social networks (2.98%), Government Policies and Incentives (9.50%), farmers' knowledge and awareness (9.50%), and perceived agronomic benefits (4.13%) have smaller but still notable effects. To enhance the adoption of agricultural travertine, policymakers should prioritize improving agricultural training, especially tailored to specific agroecological zones, and increase access to credit. Secure land tenure policies, government incentives, and promoting farmers' knowledge and social networks are essential. These interventions will encourage sustainable practices, boost productivity, and foster long-term agricultural development.
It is highly recommended for further researchers on how to establish a sustainable travertine supply chain (mining, processing, distribution) and conduct cost-benefit analysis comparing travertine to lime/fertilizers.

Quality assessment of biscuits enriched with taro flour

J.B. Dusabumuremyi — 2025-05-16

The incorporation of alternative flours from roots and tubers has garnered interest due to their potential to enhance the quality profile of bakery products. This study explored the development of biscuits formulated with composite flours comprising wheat and taro (Colocasia esculenta) flours. Taro corms were processed into flour through blanching, drying, and milling before being incorporated into wheat flour at substitution levels of 0%, 20%, 30%, and 40%. The functional properties of mixed flours, the proximate composition, mineral content, physical attributes, and sensory characteristics of the biscuits were evaluated. Results showed that taro flour inclusion enhanced water absorption capacity (WAC) and bulk density while decreasing foaming capacity (FC), foaming stability (FS), and oil absorption capacity (OAC). Proximate analysis revealed significant increases in fiber, ash, and carbohydrate content, with corresponding decreases in protein and moisture. Mineral analysis demonstrated marked increases in copper, zinc, potassium, and phosphorus, highlighting the nutritional potential of taro flour. The sensory evaluation identified the 70:30 wheat-taro ratio as the most acceptable blend, offering balanced textural and flavor properties. The findings underscore the potential of taro flour as a functional and nutritional ingredient in baked goods, offering benefits such as enhanced mineral content and dietary fiber. This study provides a foundation for the development of value-added, health-promoting biscuits, particularly suitable for resource-limited regions and health-conscious consumers.

Development and evaluation of the nutritional quality of maize-based flour

S. Ndindiriyimana — 2025-05-16

Composite flours, formulated by blending diverse raw materials, offer a practical solution for enhancing the nutritional profiles of staple foods. This study investigated the nutritional enhancement of composite flours formulated from maize, soybean, carrot, and milk powder. The raw materials were sourced locally in Rwanda and processed into fine powders through cleaning, milling, and sieving procedures. The composite flour was formulated by blending maize flour, soybean flour, and carrot powder in different ratios, maize: soybean: carrot powder: milk powder (100:0:0:0; 50:30:20:0; 50:30:0:20; 50:30:10:10; 60:20:10:10. Results revealed that soybean flour exhibited the highest protein content (37.41%), while milk powder dominated in fat (28.2%) and mineral content, notably potassium (360 mg/100g), manganese (0.75 mg/100g), and iron (12.7 mg/100g). Carrot powder contributed significantly to crude fiber (87.75%) and vitamin C (34.98 mg/100g), while milk powder excelled in vitamin A (18 mg/100g) and C (80 mg/100g). Mixed formulations showcased synergetic effects, particularly in zinc and vitamin retention. Among the tested formulations, the 60:20:10:10 blend emerged as the most nutritionally balanced, offering an optimal profile of protein, fat, and micronutrient profiles, emphasizing milk powder's fortifying potential. This study highlighted the potential of composite flours in addressing nutrient deficiencies and promoting balanced diets, with significant implications for public health nutrition in vulnerable communities.

Comparative assessment of organic and inorganic fertilizers on production and economic performance of common beans (Phaseolus vulgaris L.) under regenerative agriculture in Rubavu and Rutsiro Districts, Rwanda

A. Karangwa — 2025-05-16

Common beans (Phaseolus vulgaris L.) are a staple crop in Rwanda, providing a critical source of protein, vitamins, minerals, and dietary fiber for millions of households. The crop also plays a vital role in food security, soil fertility improvement (through nitrogen fixation), and income generation for smallholder farmers. Given Rwanda’s high population density and limited arable land, enhancing bean productivity is crucial for sustainable agriculture and economic growth. The objective of this study was to evaluate the performance of organic and inorganic fertilizers on the growth, yield, and economics of common beans (Phaseolus vulgaris L.) in Rubavu and Rutsiro districts of Rwanda. The field experiments were conducted during the cropping season 2022-A from September 2022 to January 2023 and were laid out in Randomized Complete Block Design comprising six treatments: Control, Compost, Farm Yard Manure, Bio-slurry, Di-Ammonium Phosphorus, and Complete Biological Xtract [CBX] in three replications. Data on growth, yield, and economics were gathered and analyzed. Results from ANOVA showed that there was a significant difference among treatments (p < 0.05). The yield increments compared to the control were 247.8%, 182.1%, and 169.1% for the compost, Bio-slurry, and FYM, respectively, in Rutsiro District, and 251.5%, 184.8%, and 171.7% in Rubavu District. Treatments revealed a Benefit-Cost Ratio ranging from 0.20 to 1.92. The application of compost, bio-slurry, farmyard manure (FYM), and CBX fertilizers demonstrates a significant positive impact on common bean growth and yield, suggesting their potential as valuable amendments for growers

The potential of sustainable maize production under regenerative agriculture through mulching practices at the model farm of Busogo campus in Rwanda

S. Musanabaganwa — 2025-05-16

The global agriculture sector is greatly at risk from climate change, which causes alteration of weather patterns, soil degradation, and substantial soil drought, leading to insufficient water for crop cultivation. This has contributed to reduced yield for major crops including maize, hence, increased food insecurity. Consequently, the present study aimed to investigate regenerative agricultural practices’ effects like mulching practices on yield and quality of maize as one of sustainable agriculture practices to impact climate change on maize yield. To achieve this, the field experiments were conducted in Busogo sites across two seasons 2022B and 2023A using Randomized Completely Block Design (RCBD) to assess the effects of different types of mulching materials (bean straw, Mucuna pruriens, Desmodium uncinatum, Lablab purpureus) on key growth parameters, yield components, and grain quality of maize. A significant difference in maize yield parameters such as cob height, number of grains per maize cob as well as maize grain yield per hectare had been observed also across the treatments. However, there was no significant difference observed in number of cobs per plant. It also revealed that there was no significant difference in the assessed maize grains quality parameters grown under various mulching materials. Overall, the findings of this study highlight that the living mulch Mucuna pruriens and Desmodium uncinatum should be considered for improving maize yield.

The bioeconomic profitability of non-timber forest products in the national building: A Review

K. K. Aleru — 2025-05-16

This paper reviews the bioeconomic profitability of non-timber forest products (NTFPs) to highlight the importance, prospects, and economic profitability of these resources for nation-building. The contribution of NTFPs to national development is invaluable and plays a crucial role in driving economic growth and sustainability. However, awareness and knowledge about the economic value of NTFPs for both subsistence and commercial purposes remain limited, especially among households and within government sectors. The sustainable utilization of NTFPs for commercial purposes is a viable strategy to strengthen people's ability to overcome poverty while also contributing to the growth of a country's Gross Domestic Product (GDP). The depletion of NTFP resources due to unchecked harvesting, deforestation, and environmental degradation is also a significant challenge that can impact livelihoods dependent on NTFPs as well as the economies of every nation. As such, raising the awareness of the importance of NTFPs, the economic empowerment of rural dwellers through small and medium scale enterprises (SMEs), encouragement of improved product handling, and with the vast land in Nigeria, a tap into this all-important sector can bring about a boost to the economy; and reduce other social vices in the society.

Opportunities and challenges in native species reforestation on smallholder farms in Rwanda: A Review

E.N. Bapfakurera — 2025-05-16

Native species reforestation plays a pivotal role in reversing land degradation, enhancing biodiversity, and promoting climate resilience, particularly in biodiversity hotspots such as western Rwanda. This meta-analysis synthesizes findings from 72 peer-reviewed articles and gray literature sources to evaluate the effectiveness, limitations, and opportunities of integrating native tree species into smallholder farming systems. The analysis was done by using PRISMA guidelines to ensure methodological transparency and statistical rigor, applying random-effects models to calculate effect sizes. The findings reveal significant variability in success rates across projects, with influencing factors including farmer training, financial support, ecological suitability, and policy environments. Practical implications highlight the importance of participatory planning, diversified funding, and capacity-building to enhance reforestation outcomes. The study concludes by offering policy recommendations and research priorities aimed at strengthening the implementation and impact of native species-based reforestation in Rwanda’s rural landscapes.

Nutrient distribution under boundary-based Grevillea robusta agroforestry systems in semi-arid regions of Rwanda

D.B. Ihumure — 2025-05-16

Land degradation and the decline of soil fertility are significant challenges for agriculture in semi-arid regions. Agroforestry systems offer a sustainable, nature-based solution for restoring degraded land and improving soil health. This study assessed the nutrient distribution in boundary-based Grevillea robusta systems across five sites in the peripheral Kigali and the Eastern Province of Rwanda. A gradient analysis was conducted at four distances from the tree rows (1, 3, 10, and 30 m) and at two soil depths: topsoil (0–30 cm) and subsoil (30–60 cm) in 60 farms equally distributed in the research area. The analysis was done on soil pH, soil organic matter, macronutrients (N, P, K, Ca, Mg), micronutrients (Zn, Cu, Mn, Fe), texture, and bulk density. Results showed a significantly higher nutrient concentration at distances closer to the tree rows, especially at 1 m, compared to the open areas at 30 m. The presence of tree row on boundaries increased soil organic matter (48.6%), pH (54.6%), available P (31.5%), total N (44.4%), Ca (17.4%), Mg (5.9%), and Fe (13.1%), along with a decline of soil bulk density at 9.0%. These findings highlight the potential of boundary-based Grevillea robusta to enhance soil fertility and improve soil properties in degraded lands of semi-arid regions. Further research should investigate long-term nutrient dynamics and tree-crop interactions to enhance soil health and crop yield in improved boundary-based AF systems.