Influence of Nitrogen and Phosphorus Rates on the Growth of Water Hyacinth (Pontederia crassipes Mart.)

Abstract

Research has been conducted globally to investigate the growth and colonization patterns of Pontederia crassipes Mart. This research aimed to examine the impact of varying rates of nitrogen (N) and phosphorus (P) on the growth of P. crassipes and determine the nutrient levels that would result in the greatest growth response. P. crassipes plants were placed in plastic containers filled with 5 L of distilled water. Nitrogen and phosphorus were applied separately at varying concentrations. Specifically, N was added at 0, 10, 20, 30, 40, or 50 mg L^-1 and P at 0, 1, 3, 5, 7, or 9 mg L^-1. P. crassipes demonstrated high nutrient uptake efficiency, absorbing 57% to 87% of applied N and 96% to 99% of the applied P. Total weekly biomass increased with N application to an optimal concentration of 25 to 30 mg N L^-1, after which growth declined. Leaf production was highest at 30 mg N L^-1, while N and P both accelerated offshoot production, with optimal reproductive growth and flowering observed at 20 mg N L^-1. No significant effects were observed with varying P rates on biomass or leaf production, suggesting that P may not be a limiting factor under the conditions evaluated. Overall, these findings indicate that P. crassipes efficiently utilizes N and P, contributing to its widespread abundance. In areas with high concentrations of these nutrients, P. crassipes is likely to thrive and continue to proliferate, underscoring the need for effective management strategies to mitigate its ecological impact.