The effect of tillage, cropping system, variety, and nitrogen fertilizer levels on maize production

Abstract

Climate variability and declining soil fertility are constraining agricultural productivity in Uganda. Climate smart agricultural practices are needed to improve the situation. The study tested four practices: cropping system, variety, tillage methods, and use of inorganic fertilizer in different combinations in factorial designs on-farm and on station. Data was taken on plant height, leaf area index (LAI), number of green leaves/ plants, number of cobs/plots, yield/plot, and stovers’ dry weight. Results indicated that the only significant interaction of the factors was of variety and tillage system on plant height. Otherwise, the factors impacted the response parameters as sole entities. Longe 10H was the variety with taller plants and higher yields especially under reduced tillage. Maize monocrop had the most green leaves throughout the season but lower values of leaf area index than the intercrops; maize in the intercrop also had more cobs and yield per plot. Application of N brought about significant responses for all growth and yield parameters. The application of N fertilizer at the rate 60 kg ha-1 (100% recommended) and above significantly improved all growth and yield parameters. Solely, Longe 10H maize variety produced more yield than Kawanda. Therefore, a strategy including maize variety Longe 10 H variety intercropped with beans under reduced tillage, and given 60 kg ha-1 N fertilizer a season can be used as a CSA practice to sustainably increase maize productivity. Key words: Climate smart agriculture, intercropping, nitrogen fertilizer, reduced tillage, Uganda.