Improvement of Vegetable Production Using Quartz Porphyry Treated Nutrient Solution: An Emerging Technology for Future Food Production

          As the world population continues to grow there is great pressure to find land that is fit for irrigation and agriculture, water, energy, and biological resources to provide an adequate supply of food. But because of use of unviable technology, population pressure and wasteful agricultural practices, efforts to increase food production have had an adverse impact on the environment. New production technology for high quality and high quantity agricultural products, quality irrigation water should be considered, and hydroponics can be used to improve water use efficiency. Quartz porphyry (QP) is a kind of natural rock that have additional negative charge (pH-dependent charge) used in the study in treating nutrient solution for improved cultivation of komatsuna (Brassica rapa L.nothovar) vegetable. During greenhouse cultivation in this experiment, pH of the nutrient solution decreased anomalously in higher rate at control in the initial days of experiment, while pH were not changed significantly in the same days at test, and then decreased linearly. ORP changed antagonistically in between test and control during the whole cultivation days. Electrical conductivity (EC) increased linearly in each experimental day at control and test. The production of komatsuna vegetables improved in receiving QP treated nutrient solution (test) compare to the control. The treatment with QP in the nutrient solution reduced excessive concentrations of NO₃^- and SO₄^2- ions which caused the decrease of salinity and toxicity effects that might be some of the factors for improvement of plant production. Re-circulation of water with QP particles in hydroponics cultivation reduces irrigation amount and nutrient application improved efficient use of mineral nutrients and reduced the contamination of water.