Journal of Agricultural Sciences and Engineering

Abstract: This comprehensive review examines the critical interactions between climate change, carbon balance, and cereal crop productivity, with a strong emphasis on carbon sequestration and climate-smart agricultural practices. Climate change poses substantial risks to cereal-based food systems through increased frequency and intensity of drought, heat stress, and variability in rainfall patterns, leading to yield instability and declining soil health. To sustain cereal productivity and global food security, adopting climate-resilient crop varieties, improved nutrient and water management, and soil conservation practices are essential. The review highlights the role of soil carbon sequestration as a key climate mitigation strategy, emphasizing the contribution of conservation agriculture, organic amendments, diversified cropping systems, and biochar application in enhancing soil organic carbon stocks while reducing greenhouse gas emissions. Crop physiological responses to climate stress, including changes in photosynthesis, water-use efficiency, and nutrient uptake, are discussed in relation to their influence on carbon dynamics and yield formation. Despite the mitigation potential of these approaches, significant challenges remain in their large-scale adoption, particularly in smallholder farming systems. Integrated strategies that combine crop breeding, agronomic management, and supportive policy frameworks are therefore crucial for developing resilient, productive, and environmentally sustainable cereal production systems under a changing climate.

Abstract: The utilization of dietary fibers extracted from agricultural wastes such as lettuce and tomato represents an innovative approach in developing food products focused on sustainability and consumer health improvement. This review article provides a comprehensive evaluation of the role of fibers derived from lettuce and tomato wastes in formulating high-fat prebiotic sauces. According to optimization results for tomato pomace aimed at producing a modified fiber supplement suitable for high-fat prebiotic sauce, the following properties were obtained: bulk density of 0.6 g/cm³, water activity of 0.17, oil absorption index of 2.6, antioxidant activity of 35.14%, and lightness (L*) value of 57.18. These findings indicate that tomato and lettuce waste fibers not only improve the technological and functional characteristics of sauces, but also support gut microbiota due to their prebiotic potential. Moreover, valorizing these agricultural by-products aligns with circular economy principles, reducing environmental impact while enhancing the nutritional profile of high-fat products. This review highlights the promising application of vegetable waste fibers as functional ingredients in the development of healthier, more sustainable sauce formulations.

Abstract: Sweet potatoes are the most important root crop in several African countries, including Ethiopia. Nevertheless, its development is hampered by the nutrients in soil and plant materials. To address these problems, a field study was conducted in the districts of Bako and Wayu Tuka during the 2023/2024 growing season to assess how fertilizer rates affected root yield and yield parameters. Four nitrogen levels (23, 46, 69, and 92) and three levels of NPSB kgha⁻¹ (100, 150, and 200) fertilizer rates were used in the experiment. It was set up in three replications using a factorial arrangement, RCBD. The study examined the effects of nitrogen and NPSB fertilizer rates on vine length, vine internode length, petiole length, storage root thickness, large root diameters, large root width, and storage root yield (57884 kg ha⁻¹) and recorded them from 69 kg N and 200 and 100 kg NPSB ha⁻¹ at the Bako and Gute sub-sites, respectively. The application of 69 ha⁻¹ nitrogen and (200 and 100) kg ha⁻¹ The NPSB fertilizer rate resulted in the highest yield of sweet potatoes (61,142.86 & 9,905 kg ha⁻¹) from the Bako and Gute locations, with the highest net benefit of 1,209,136 & 188,284.20 ETB ha⁻¹ with an acceptable marginal rate of return. According to the study's findings, sweet potato productivity and profitability in the Midland agro-ecologies of western Ethiopia are greatly increased by supplementing the optimum amount of nitrogen and NPSB fertilizer rates.

Abstract: Starch is an essential biopolymer traditionally sourced from cassava, corn, and potato, with widely used applications in the food, pharmaceutical, and cosmetic industries due to its biodegradability, biocompatibility, and functional versatility. However, the growing demand for conventional starch sources raises sustainability and food security concerns. Mango (Mangifera indica L.) seeds, which constitute approximately 10–25% of the fruit’s total weight, are commonly discarded as agro-industrial waste byproduct despite being rich in starch. Mango seed starch has recently been used as an alternative source of starch due to its desirable physicochemical and functional properties. This review examines starch derived from mango seed kernel as an eco-friendly source for starch based biopolymers, detailing extraction methods, chemical composition, physical properties, structural modifications, and food packaging applications. The starch exhibits high gelatinization temperature and shear resistance, making it suitable for active packaging, edible films, and industrial coatings. However, issues exist regarding presence of anti-nutritional factors, toxic compounds, inadequate processing setups, and regulatory constraints. Future research should focus on improved extraction and modification techniques, alongside sustainability assessments, to enhance the commercial viability and sustainable utilization of mango seed starch.

Abstract: Fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), is a major pest of maize, and its control requires the use of insecticides. The increasing prevalence of insecticide resistance in S. frugiperda highlights the urgent need for new, effective, and environmentally safe strategies. Azurin, a redox-active protein produced by Pseudomonas aeruginosa, was evaluated for its insecticidal potential against S. frugiperda larvae. Biochemical assays measured the effects on nutritional physiology and enzymatic activities in larvae. Larval bioassays revealed that azurin exhibited potent toxicity, with an LC₅₀ values of 94.40, 42, 13.30, 3.55 µg/mL after 24, 48, 72 and 96 h, respectively of exposure. The larval mortality rate increased in a time- and dose-dependent manner. Azurin also negatively affected the development of insect along with significant decline in relative growth and consumption rate as well as efficiency of conversion of ingested and digested food of insect. The azurin significantly decreased the reproductive potential of insect. A significantly decrease in the activity of various digestive enzymes and detoxifying enzymes was also observed that might be associated with reduced survival of this insect. These results suggest that azurin exhibits significant larvicidal activity and the ability to disrupt S. frugiperda metabolism functions, making it a promising candidate for controlling this pest.

Abstract: Microalgae are tiny microscopic prokaryotic and eukaryotic organisms that serve as a partial substitute for conventional synthetic fertilizers. The application of microalgae as biofertilizers and biostimulants has been shown to positively influence both the above- and below-ground growth of plants. Rich fertile land is an essential resource for farmers. Nevertheless, the poor farming practices can lead to soil degradation and loss of nutrients. The efficacy of microalgal biofertilizer and biostimulants is greatly influenced by a number of critical factors. The method of application and their combinations with organic amendments result in their distinct effects depending on the crop and the desired outcome. Concentration and dosage play vital roles; as a general rule, low to moderate concentrations are effective, while high concentrations may produce inconsistent and even harmful results on plant growth and physiology. This review article studies last five years of research from onwards and provides a brief review of the microalgae applications across crops, highlights mechanisms, identifies key knowledge gaps and future perspectives for research.