Background of Study
Maize (Zea mays L.) is a staple crop in Kenya, particularly in semi-arid regions such as Nyatike sub-county. However, low soil fertility and inadequate fertilizer application have limited maize production in these areas. Understanding the physio-agronomic response of maize hybrids to different rates of NPK fertilizer is crucial for optimizing yield and profitability.
Physio-Agronomic Response of Maize Hybrids to NPK Fertilizer Rates
The application of NPK fertilizer has a significant impact on the physio-agronomic characteristics of maize hybrids, including:
- Growth and Development: NPK application promotes plant growth and development by providing essential nutrients for photosynthesis, protein synthesis, and root formation.
- Leaf Area Index (LAI): Higher NPK rates result in increased leaf production, leading to a larger LAI and improved light interception.
- Chlorophyll Content: Nitrogen (N) application enhances chlorophyll production, promoting photosynthesis and leaf greenness.
- Plant Height and Stalk Diameter: Adequate NPK fertilization improves plant height and stalk diameter, increasing lodging resistance.
- Days to Maturity: NPK application can hasten crop maturity, facilitating timely harvesting and reducing exposure to environmental stresses.
Effect on Grain Yield and Yield Components
NPK fertilizer rates influence maize yield and yield components, including:
- Grain Yield: Balanced NPK application optimizes grain yield by supplying essential nutrients for kernel development and filling.
- Ear Number per Plant: Nitrogen (N) promotes tillering, resulting in higher ear numbers per plant.
- Grain Number per Ear: Phosphorus (P) enhances pollen production and grain set, leading to increased grain numbers per ear.
- Grain Weight: Potassium (K) plays a role in carbohydrate translocation and starch accumulation, contributing to heavier grains.
- Harvest Index: NPK application improves the harvest index by increasing grain yield relative to total biomass production.
References
- Adu-Gyamfi, J. J., et al. (2013). Effects of NPK fertilizer rates on growth and yield of maize (Zea mays L.) under different water regimes. International Journal of Plant & Soil Science, 2(1), 16-23.
- Chivenge, P., et al. (2011). Maize response to NPK fertilizer rates in two agro-ecological regions of Zimbabwe. Agronomy for Sustainable Development, 31(3), 533-543.
- Mucheru-Muna, M., et al. (2014). Maize response to NPK fertilizer rates in the semi-arid region of Kenya. African Crop Science Journal, 22(2), 235-246.
- Sánchez, P. A., et al. (2015). The role of nutrients in enhancing resilience of cereal crops to climate variability. Plant and Soil, 394(1-2), 395-409.