Comparação entre dois modos de irrigar vasos em casas de vegetação

Resumo

The objectives of this experiment were: 1) to compare methods of watering plots in a greenhouse and 2) to study different types of cotton wicks and the heigh of wicks in the pots. A medium texture dark yellow latosol soil was used. 

In the first experiment, surface watering was compared with capillary watering using a commercial cotton wick. Three different diameters of wicks were used. The wicks extended from the botton of the pots to the surface or from botton to about one-half the distance to the surface. The dry weight production of Italian millet was measured at 30 days after planting.

In the first experiment, fertilization and irrigation sig nificantly increased the dry matter production, but the different wick diameters and placement did not affect the dry matter production.

In the second experiment, the millet was eliminated and phosphorus and potassium were added to the water. The phosphorus and potassium levels were determined at three different elevations in the pots. The phosphorus did not rise above the lower third of the pot, while the potassium rose to the upper one-third.

The location of the phosphorus and potassium was not influenced by the wick diameter and placement. The levels of calcium and magnesium were higher in the upper one-third of the pot even though these elements were not added to the water.