Studies on Improvement of Nutrient AND Water Supply in Crop Cultivation on Sand Dune Soil: I. Comparison of Irrigation Methods

Tomatoes (Lycopersicon esculentum Mill. var. Houfuku) were grown in sand dune soil cultures that were watered either by surface, sprinkler, or drip irrigation. Plant response to the irrigation method was evaluated in terms of nutrient uptake, water use, and dry matter production. The rate of evaporation from the soil surface during sprinkler irrigation was higher than that for surface irrigation in spite of the fact that the wetted surface was the same for both methods. Sprinkler irrigation resulted in severely drought-stressed plants and both nutrient uptake and dry matter yield were lowest by this irrigation method. Soil water contents were highest during drip irrigation. This method seemed to be most efficient from the standpoint of water management on sand dune soil. However, only a portion of the nitrogen and phosphorus applied to the soil moved into the root zone. Consequently the levels of these nutrients in the plants were lower than those in plants irrigated by either the surface or sprinkler method. It is concluded that fertilizers must be carefully placed in drip-irrigated sand dune soil to ensure that essential nutrients are made available to the crop.