Plant root templated irrigation
Due to the decreasing availability of water resources and the increasing competition for water between residential, industrial, and agricultural users, increasing irrigation efficiency, by modern efficient irrigation technologies such as subsurface drip irrigation (SDI), is a pressing concern for agricultural authorities. In this study, a new method is explored for subsurface irrigation; the plant root template structure is used as the subsurface water distribution system. Plants are severed from the stem part and then attached to a pressurized water source such that water may permeate into surrounding soil through the existing buried root system. This pressurized root system then serves as well distributed buried irrigation water source to the other nearby growing plants up taking water. The feasibility of using an existing root structure being able to supply water at rates necessary to satisfy other growing plants was determined by conducting laboratory water permeability studies. Laboratory growth studies were used to directly test the proposed root templated irrigation (RTI) approach. Modeling simulations are also utilized to extend laboratory findings to other scenarios and compare expected water use efficiency benefits associated with this proposed irrigation method with SDI and surface irrigation (SI) practices.
Irrigation study measurements showed that, RTI provides more efficient water use as compared to SI. After 25 days of irrigation, it was shown that RTI of tomato plants provided 1100% increase in growth rate and 54% increase in plant stem density in comparison to SI. Modeling calculations were in qualitative agreement with the experimental studies indicating that RTI has 142% improvement in root water uptake over the SI. A modeling comparison of SDI waster use at various source spacing to RTI water use in loam and clay was performed and results showed that RTI is superior to SDI unless SDI source spacing is narrow (25 cm).