摘要：Abstract
Background
Phosphorus is believed to be the second most limiting nutrient for crop growth and development in acidic soils. It is mainly because the amount of P in the soil is inherently low and part of it is fixed and made unavailable to plant uptake. Therefore, the objective of this research was to study the response of maize to mineral P fertilizer application and evaluate its economic feasibility on acidic Alfisols of North-western Ethiopia.
Results
Results of the experiment indicated that phosphorus fertilizer rate had a significant (p < 0.05) effect on plant height, shelling percentage, number of kernel per ear, number of ears per plant, grain yield, dry stubble yield and dry biomass yield. However, it did not have a significant effect on lodging percentage and 1000-grains weight. Increasing the P rate only up to 30 kg P2O5 ha−1 gave a significant grain yield increase over the control. Similarly, the marginal rate of return (MRR) analysis showed that the same rate gave MRR of 67.8 % while others were dominated by the same.
Conclusions
From the results of the experiment it was possible to conclude that, in the presence of sufficient amount of N and K fertilizers, maize is responsive only to lower levels of phosphorus fertilizer application. Apparently, the fertilizer application at the rate of 30 kg P2O5 ha−1 gave maximum profit from unit investment. Going beyond this P level did not bring profitable yield increase.
关键词：KeywordsEnAlfisolsMarginal rate of returnOptimum grain yieldP fertilizer rate
