Plant Talk: A Study of Interorganismic Communication Using Physical Adaptations of Phaseol

­­­­­­­The purpose of this project was to measure interorganismic communications through growth pattern responses in Phaseolus vulgaris plants when neighboring plants were exposed to high levels of lead. It was hypothesized that unexposed Phaseolus vulgaris plants would exhibit physical changes in response to lead exposure in neighboring bean plants. Containment systems were built using plant trays and cellophane. Beans were planted in a potting soil and once they reached a viable height, twenty were placed in each containment system, ten were exposed to lead and ten were not. Each test group consisted of two complete containment systems of 40 plants. Test groups received 100ppm lead, 250ppm lead, 350ppm lead, and 500ppm lead. Every three days plant height and leaf number was measured. Once a week stem diameter and color change were measured. One measure of biomass and root length was taken on day 14. All treatment groups had a significantly higher number of leaves, and all groups except unexposed and exposed 350ppm lead and exposed 500ppm lead were significantly taller compared to the control plants. There was little to no color change within the plants, however, all treatment groups had a significantly higher stem diameter. Exposed and unexposed 250ppm lead and unexposed 500ppm lead had significantly longer root lengths. All treatment groups had a higher biomass per plant compared to the control.