Effect of Silver nanoparticles on tomato plants and Development of a Plant Monitoring System (PMS)

Abstract

Smart Agriculture will determine whether farmers in the US can compete internationally. Engineering plays a significant role in Smart Agriculture through the development of sensor networks, data acquisition, and control systems that will help advance the fundamental understanding of food quality and plant growth. In this thesis, two issues related to engineering in Smart Agriculture are studied: 1) the influence of nano-materials on plants; and 2) the development of a plant monitoring system. The influence of silver (Ag) nanoparticles on tomato plant growth is studied. Silver nanoparticles have become a significant tool in the development of novel biological and chemical processes. Silver nanoparticles have unique physical and chemical properties, such as the ability to kill or impede growth of bacteria and microorganisms such as E. coli. With the growth of silver nanoparticles usage, it is only a matter of time before silver nanoparticles are heavily distributed into the ecosystem. For that reason, it is critical to study the long-term effects of silver nanoparticles on our food supply, such as plants and crops. In this study, tomato plants are grown hydroponically, in solution with known concentrations (1.97x1013 and 1.57x 1011) of silver nanoparticles. Silver nanoparticles ranging in sizes from 10 nm to 50 nm were investigated. The uptake or absorption of the silver nanoparticles by the tomato plants was monitored using a Ultra-Violet/vis Spectrophotometer. Material characterization technologies, such as X-ray Diffraction, Raman Spectroscopy, and Energy Dispersive Spectrometer were then used to determine the location of the silver nanoparticles in the plants. The growth of plants was visually observed and recorded. Based on experimental results, it was concluded that tomato plants uptake the silver nanoparticles from the hydroponic solution and these silver nanoparticles led to the death of the plants. It was also found that the smaller the silver nanoparticles, the quicker the tomato plants die. This thesis also investigated the use of sensors, data acquisition systems, and wireless networks to monitor the growth and health of plants. A plant monitoring system was designed and fabricated to monitor plants. This system was designed to operate over a wide temperature range, have low-power consumption, and be robust in nature. A multitude of sensors was wired to the data acquisition system. Bluetooth, the wireless protocol of choice, was then used to communicate the information from the data acquisition system to a remote computer monitoring station. The system monitored and recorded temperature, humidity, soil moisture, and ripeness of fruit and/or vegetables.