UPLAND RICE PHENOLOGY AND NUTRIENT UPTAKE IN TROPICAL CLIMATE

Abstract

Understanding rice phenology and nutrient uptake pattern is important for adequate crop management and improving yields. A greenhouse experiment was conducted with the objective to monitoring upland rice (cv. Talento) phenology and nutrient uptake pattern during its growth cycle. Growth observations and plant analysis were performed at initiation of tillering (IT), active tillering (AT), panicle initiation (PI), booting (B), flowering (F) and physiological maturity (PM). Shoot dry weight plus grain yield and root dry weight increased significantly (P < 0.01) with age and followed exponential cubic responses. Similarly, plant height, number of tillers per plant, number of leaves on main culm and maximum root length increased significantly (P < 0.01) in quadratic fashion with increasing plant age. Concentrations of nitrogen (N), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe) and manganese (Mn) increased significantly (P < 0.01) and quadratically with plant age, whereas, phosphorus (P), copper (Cu) and zinc (Zn) decreased quadratically with increasing plant age. Uptake of macro- and micronutrients increased significantly in quadratic fashion with increasing plant age. Plant growth parameters had highly significant (P < 0.01) association with shoot dry weight plus grain yield in the order of shoot dry weight > root dry weight > plant height > root length. Similarly, uptake of macronutrients also had highly significant (P < 0.01) association with dry matter plus grain yield in the order of Ca > Mg > K > P > N, indicating deficiency of these nutrients in Brazilian Oxisols for rice production.

Keywords:

• cerrado soil
• root dry weight
• root length
• shoot dry weight
• Oryza sativa L.