Sustainable management of potassium nutrition in alfalfa crop production is one of the major key factors for achieving optimum seed and biomass yields. An inappropriate supply of mineral potassium nutrition in alfalfa production could result in a decrease in biomass and grain yield production, leading to luxury consumption with cost implications. Alfalfa (Medicago sativa L.) is a perennial leguminous forage crop known for its high protein content, nutritive value, biomass yield production, soil-improving abilities, and livestock feed. Potassium nutrition plays a crucial role in alfalfa production by influencing several physiological processes essential for biomass yield, growth, development, photosynthesis, nutrient uptake, and stress tolerance. Although several studies have been conducted regarding the role of potassium nutrition in agriculture productivity, only limited research has focused on crop-specific impacts. Therefore, this paper reviews (i) the significant role potassium nutrition plays in alfalfa production along with its implications for quality, yield, growth, and resistance to abiotic stress; (ii) the factors affecting the availability, absorption, and transport of potassium; (iii) the source of potassium and the consequences of inadequate availability; and (iv) highlights some strategies for mitigating potassium nutrient deficiency to optimize alfalfa productivity and sustainability in agricultural systems.

This systematic review critically evaluates and synthesizes current evidence on the efficacy of biostimulants in enhancing soybean seed yield and quality. A comprehensive literature search was conducted following the PRISMA approach using the Web of Science (WoS) database, focusing on peer-reviewed studies from 2014 to 2025 reporting on the effects of biostimulants applied alone or in combination with other agro-inputs on soybean performance. Over 500 publications were retrieved from the database, of which 72 were included in this review. Extracted data were used to calculate changes in yield (kg ha⁻¹), percentage yield increase (%), oil content (%), and protein concentration (%). Our synthesis demonstrated that the sole application of biostimulants, including seaweed extracts, humic acids, amino acids, and beneficial microbes (Bradyrhizobium, PGPR, AMF), consistently enhanced soybean yield by 4% to 65%, while their interaction with other agro-inputs was shown to be capable of increasing yield by more than 150% under abiotic stress conditions, indicating strong synergistic effects. These improvements are mediated through various physiological mechanisms such as enhanced nutrient uptake, improved root growth, increased photosynthetic efficiency, and elevated stress tolerance. Furthermore, biostimulant application positively affects seed quality, increasing oil and protein content by 0.4–5.5% and 0.5–7.3%, respectively, by optimizing source–sink relationships and metabolic pathways. Overall, the greatest benefits are frequently observed through synergistic combinations of biostimulants with one another or with reduced rates of mineral fertilizers, highlighting a promising pathway toward sustainable crop intensification in soybean systems.

To help economize fertilizer use and predict soil-based and site-specific fertilization regimes in crop production, knowledge on crop response to incremental rates of nutrition have long been identified to play a significant role. In the nutrient-poor lixisols of northern Ghana where bulk of Ghanaian maize is produced, the response of maize growth and yield to eleven rates of N fertilization was evaluated in 2019 as a first step in developing a tool that could predict site-specific nitrogen rates for optimum maize production. The rates were 00, 15, 30, 45, 60, 75, 90, 105, 120, 135, and 150 kg/ha; laid out in a Randomized Complete Block Design. Collected maize growth and yield data were subjected to analyses of variance, where significantly different means were separated at a probability of 5% using the least significant difference. The study revealed no significant differences in plant height from the third to sixth week after planting, days to 50% flowering, 100 grain weight, and leaf area index at sixth week after planting. However, plant height and leaf area index at ninth week, cob weight, cob length, straw weight and grain yield were significantly affected by N fertilizer rates. Increasing nitrogen fertilizer rates had a pronounced effect on later-stages of growth, on grain yield and on yield components of maize.  Application of 120 to 150 kg/ha N achieved statistically similar, and maximum growth and yield parameters compared to lower rates. The findings provide essential agronomic data required to relate soil test results with corresponding maize yield.

Recent studies have found compelling evidence that enhancing photosynthetic mechanisms through genetic engineering can increase crop yield potential. This paper focuses on cowpea productivity in Sub-Saharan Africa, its importance, factors limiting photosynthetic potential, and techniques towards boosting cowpea photosynthetic efficiency. High light intensity, low temperature, low CO₂ environment, and water scarcity have all been identified as key limiting factors for crop photosynthetic efficiency. Deactivation of Rubisco functioning in shade has also been noted to reduce cowpea photosynthetic potential. However, recent successes have been observed through genetic manipulation of photosynthesis traits so as to improve photosynthetic efficiency and yield under control conditions with considerable increase in yield from 14 to 40%. Thus, improving photosynthesis has the potential to increase crop productivity.

This study evaluated the effects of foliar silicon (Si) and sulfur (S) applications under contrasting climatic conditions on macro- and micronutrient accumulation in oat grain. The three-year field experiment (2022–2024) was conducted in Debrecen, Hungary, using a randomized complete block design (RCBD)with three replications. Grain samples were analyzed for macroelements (K, P, S, Mg, Ca) and micronutrients (Na, Si, Fe, Mn, Cu). Environmental conditions markedly influenced nutrient accumulation. Severe drought promoted the highest concentrations of K, S, and Mg, while mild drought significantly increased the accumulation of P, Ca, Si, Fe, and Cu contents. Moderate drought favored Na accumulation. Foliar S application under relatively favorable water supply significantly enhanced the concentration of all measured elements, with the strongest response observed for Cu (+47.4% compared with the control) and the weakest for Mg (8.5%). In contrast, Si application alone had only limited or negative effects, particularly under severe drought, where it reduced K (6.4%), S (2.4%), and Ca (13%) concentrations, despite increased Si accumulation in the grain. During drought stress, however, the combined Si + S treatment significantly increased the grain macro- and micronutrient concentrations. Among the tested genotypes, ‘Mv Pehely’ exhibited the highest macronutrient accumulation, while ‘GK Kormorán’ and ‘Mv Pehely’ showed superior micronutrient accumulation. ‘GK Pillangó’ and ‘Mv Szellő’ showed consistently lower nutrient contents. These results highlight the importance of genotype × environment × nutrient management strategies for improving nutrient composition in oat grain.