Identifying factors that drive Yield Response of Maize to NPK

The yield response of maize to NPK fertilizer application in Ghana exhibits significant variability across different agroecological zones. This study, conducted by FERARI, utilizes advanced modeling and statistical methods to investigate the factors influencing these diverse yield responses. The analysis draws upon a comprehensive dataset comprising nearly 1,700 data points from both on-farm and on-station trials. Despite the substantial increase in fertilizer use in recent decades, maize yields have only seen modest improvements. This research builds upon a previous study by Buah et al. (2020) and seeks to address the critical question of why maize yield responses to fertilizer applications vary significantly. To understand this variability, two modeling approaches, Quantitative Evaluation of Fertility of Tropical Soil (QUEFTS) and Akaike Information Criterion in Multiple Linear Regression (AIC-MLR), were employed. QUEFTS, which focuses on soil fertility characteristics, explained 24.6% of yield variability in on-farm trials and 12% in on-station trials. AIC-MLR, which considers a broader range of factors including soil physical characteristics and climatic variables, provided a more comprehensive understanding, explaining 50% of yield variability. Soil physical factors accounted for 25% of variability, environmental factors 10%, and chemical soil fertility characteristics 33% in on-station trials, while environmental factors were more influential than physical and chemical factors in on-farm trials. Interestingly, the study revealed that fertilizer application increased both maize yield and yield stability. This information is particularly valuable for improving farming practices and increasing agricultural productivity in Ghana. In conclusion, this research highlights the need to consider not only soil fertility but also soil physical characteristics, climatic factors, and other variables when studying the impact of fertilizers on maize yield. The findings also underscore the potential impact of climate change on maize production in Ghana, emphasizing the importance of addressing these factors in agricultural planning and policy development.
Maize, NPK fertilizers, Soil fertility