Abstract: There has been increased demand for food production from greenhouse and indoor vertical farms over the last 5-6 years due to the advantages of controlling growing conditions that are favorable for crop growth, high yields, and increased energy use efficiency. However, lighting installation and operational costs account for one-third of the overall energy costs in controlled environment agriculture (CEA) production, creating a significant financial burden for CEA stakeholders. The current lighting control system only considers the target lighting levels, and any excess is wasted as heat or chlorophyll fluorescence. High light intensity significantly damages plant photosynthetic systems and reduces light-use efficiency, wasting energy. Stakeholders are demanding a more precise lighting control system for greenhouses and indoor vertical farms that accounts for both the environment and plant physiological responses. This presentation provides info on how we developed a plant chlorophyll fluorescence-based biofeedback (BFB) system with real-time light-intensity control for long-term plant growth and production. We determined the optimal plant electron transport rate (ETR) and the quantum yield of photosystem II (ΦPSII) as the reference for light-intensity control, conducted multiple tests in greenhouses and vertical farms, and established machine-learning models to predict plant photosynthetic performance under greenhouse conditions to control supplemental light levels. We generated evidence-based information for researchers and growers to use the BFB system and will scale up the technology in the near future, seeking collaborators. We are also recruiting a PhD student with a strong background in engineering and crop physiology to advance the system further. Interested candidates should apply at the ASHS website https://ashscareers.careerwebsite.com/job/phd-opening-in-horticulture-at-the-uga-caes-ferrarezi-lab/81869596 by Feb 1st, 2026. 

Bio: Dr. Rhuanito Soranz Ferrarezi is an Associate Professor of Controlled Environment Agriculture (CEA) Crop Physiology and Production at the University of Georgia’s Athens campus. He received his B.Sc. in Agronomic Engineering from the University of Santa Catarina (Brazil) in 2002, M.Sc. in Horticulture from the Agronomic Institute of Campinas (Brazil) in 2006, and Ph.D. in Agricultural Engineering from the University of Campinas (Brazil) in 2013. Dr. Ferrarezi’s program focuses on CEA Crop Physiology and Production, with an emphasis on precision irrigation, plant nutrition, biopharmaceuticals, lighting, and cropping systems for greenhouses and indoor vertical farms. Research in his laboratory is dedicated to developing new technologies to enhance vegetable and ornamental crop production in Georgia and the U.S., through both basic and applied research that utilizes sustainable horticultural practices. Dr. Ferrarezi’s specialties include ebb-and-flow subirrigation, soil moisture sensors, the development of new tools for improved irrigation and fertilization management, enhanced plant nutrition, sap analysis for CEA crops, imaging, high-throughput phenotyping, lighting, variety screening and adaptation to CEA, hydroponics, and the improvement of cultural practices such as substrate and biostimulant testing. In his instructional role, Dr. Ferrarezi focuses on workforce development by teaching undergraduate and graduate students in courses such as HORT 3200 “Hydroponics and CEA”, HORT 4050/6050 “Greenhouse Management I”, and HORT 8111 “Design, Analysis, and Interpretation of Horticultural Data”. Dr. Ferrarezi has published 98 refereed articles in top-ranked scientific journals in the horticultural sciences, and numerous abstracts, book chapters, and extension publications. His program has secured over $5 million in extramural funding from federal and state agencies and private companies to support research projects. His lab collaborates with several agricultural companies based in Georgia and maintains strong connections with growers, agricultural professionals, community leaders, researchers, and others committed to building a robust CEA industry in Georgia. Dr. Ferrarezi is an active member of the American Society of Horticultural Science, the International Society of Horticultural Science, and the American Association for the Advancement of Science.