Soil Available Nutrients, pH and Yield Variation in Legume - Maize Systems Utilizing Two Phosphorus Sources in Kabete Kenya
- Select Volume / Issue:
- Type of Publication:
- Intercropping, Minjingu Phosphate Rock, Nitisol, Nitrogen, Triple Superphosphate
- Templer, Noel A.; Lelei, Joyce J.; Onwonga, Richard N.
- Phosphorus (P) and nitrogen (N) deficiencies have contributed to low maize yields in Kabete, Kenya. A split plot in a randomized complete block experiment was set up at Kabete Field Station, University of Nairobi, during the long (LRS) and short rain seasons (SRS) of 2012. The objective was to investigate effects of legume integration and P fertilizer application on soil pH, available N and P and yields in maize systems. The main plots were sole maize, legume/maize intercrop and legume-maize rotation systems. The sub plots were Minjingu phosphate rock (MPR) and triple superphosphate (TSP) (60 kg P ha-1) application and a control (no P input). In the LRS, pH at seedling was significantly higher in chickpea/maize intercrop control and with TSP (C/MCTRL; C/MTSP), and lupin-maize rotation with TSP (L-MTSP). At flowering, pH was significantly higher in sole maize control and with MPR (MCTRL; MMPR), chickpea/maize intercrop with MPR (C/MMPR) and lupin/maize intercrop with MPR and TSP (L/MMPR; L/MTSP). At harvest, MMPR, C/MTSP and C/MMPR had significantly higher pH. During the SRS, pH was significantly higher in MMPR, C/MMPR, L/MMPR and L-MMPR at seedling, MTSP, MMPR, L/MMPR, L-MCTRL and L-MMPR at flowering and C-MMPR at harvest. In the LRS available P was significantly higher in MCTRL, C/MCTRL and C-MCTRL at seedling, L-MCTRL during flowering and L/MCTRL at harvest. In the SRS, available P was significantly higher in MTSP, MCTRL, C/MCTRL, L/MCTRL, L/MTSP, C-MTSP and L-MTSP at seedling, C-MTSP at flowering and MCTRL and C-MCTRL at harvest. During the LRS nitrate-N was significantly higher in L/MTSP at seedling, L/MCTRL and C-MTSP at flowering and L/MMPR, L/MCTRL, L-MMPR and C-MCTRL at harvest. In the SRS, nitrate-N was significantly higher in C-MMPR, L/MMPR and C-MMPR treatments at seedling, flowering and harvest, respectively. In the LRS, ammonium-N was significantly higher in MTSP, MMPR, L/MTSP, L/MMPR, L-MCTRL, L-MTSP, L/MCTRL, L-MMPR, C-MMPR, C/MTSP and C/MMPR at seedling, L/MTSP at flowering and C-MCTRL, C/MCTRL and C/MMPR at harvest. In the SRS, ammonium-N was significantly higher in C/MCTRL at seedling and flowering, and C/MMPR at harvest Maize grain yields were significantly higher in L/MTSP, L/MMPR and C/MMPR in the LRS and L-MMPR and L/MTSP in the SRS. Application of either TSP or MPR in legume-maize systems enhanced nutrient availability and maize yields. The intercropping system with MPR use may be more preferable because of dual harvest from same field.
Full text: IJRAS-515-FINALIZED.pdf