We are currently working on a research on phytoremediation of heavy metals by plants, and our research uncovered that adding chelating agents, such as ethyldiaminetetraacetic acid (EDTA) increases the plants' heavy metal uptake. However, EDTA is injected ONLY into the soil. Is it possible for EDTA to be injected into the tissues of plants instead? Wouldn't this maximize the plants' uptake more if the agent is already in its tissues?