Enhancing maize (Zea mays l.) growth and nutrient uptake via application of water hyacinth
(Eichornia crassipes [Mart.] Solms) compost and inorganic nutrients
A soil culture experiment was conducted in the screenhouse to assess the growth response of maize to water hyacinth compost application rates and their residual effects. Water hyacinth (Eichhornia crassipes [Mart.] Solms) compost, namely, 2.5 t ha-1(W1) and 5.0 t ha-1 (W2) with and without fortification with fertilizer, F [N (25 kg ha-1 as urea) and P (26 kg ha-1 as SSP)] were mixed with portions of 5 kg soil and used to grow maize. At eight weeks after planting in each of two con- secutive cropping, plant heights, biomass dry weight and their nutrient contents were determined. Soil was also sampled from each pot for chemical analyses. Compared with the control, available P and exchangeable K were increased (p<0.05) by W2F (27%) and W2 (43%), respectively. Similarly, W2F and W2 increased SOM by 86 and 107% (p<0.05), respectively, while W2F, W2 and W1F increased exchangeable Ca between 8 and 10% (p<0.05). Treatments W2F, W2 and W1F increased plant heights by 35–40% while W2 and W2F increased the dry matter yield by 72 and 75% (p<0.05), respectively. Further, sole compost or its organo-mineral form increased the tissue contents of N (98–141%), and K and Mg (103–280%). The tissue content of Ca was also increased (p<0.05) by W2F. Residual effects of the soil amendments were also significant on most tested soil and plant parameters. It was concluded that soil nutrient status, maize agronomic and nutrient uptake parameters were improved by the application of water hyacinth compost with and without inorganic N and P. The rate of 5.0 t ha-1 of the sole compost and its organo-mineral form proved superior in enhancing maize growth and soil nutrient status.