Variation in nutrient use efficiency under varying soil conditions in maize growing areas in northern zone, Tanzania- East Africa

Sub-Saharan Africa (SSA) is plagued by low maize productivity due to climate change, poverty and poor agronomic practices by smallholder scale farmers. The objective of this study was to explore the attainable maize grain yields under various nutrient use in a varying soil conditions..In order to execute the study, in year 2016/2017 maize planting season, performance trials (PTs) were extracted from the Nutrient Omission Trials (NOTs) of the season 2015/16. The PTs was an advanced of NOTs to understand the variation in nutrient use efficiency of maize under varying soil conditions. The performance Trials (PTs) were conducted in 10 different districts of main maize growing areas Northern Tanzania. The PTs sites were introduced in the same grids in which NOTs were planted. The aim of this study was to verify the performance of newly developed site specific nutrients management recommendations by Taking Maize Agronomy to Scale in Africa (TAMASA) project against the blanket recommendation. The PTs were based on nutrient expert tool and soil test (ST) based fertilizer recommendations. The treatments used were nutrient expert (NE) recommendation, soil test (ST) based fertilizer recommendation, region fertilizer recommendation (RE) and control in which no fertilizer was applied. The fertilizer rates and their ranges was as follows; RE-NPK (100-20-0), NE-standard NPK (100-20-0), Soil Test ST- NPK (102-50-46).The parameters considered were grain and biomass yields. The results showed that performance of these treatments varied within and across locations. Generally the results in Siha district showed that the grain yield was higher for NE>ST> control>RE. In Mbulu district NE and ST performed highest than RE and the control. In Babati although the difference was small still NE and ST were better than the control treatment. Grain yield in Monduli was also better for NE, ST and RE in relation to the control treatment. The treatments revealed significant variation in biomass yield as indicated in the results followed with discussion section of this study report. The study concluded that NE and ST treatments were significant that showed comparable high grain yield of maize, therefore farmers could make significant yield upon adopting of NE and ST treatments fertilizer for site specific nutrient management.