2019 ASHS Annual Conference

Crown pea plants (Pisum sativum L.) have determinate growth and also develop an enlarged meristem due to a mutation in a gene that leads to a fasciated phenotype. As a result, crown peas produce numerous flowers on a widened apex. In the current study, we used the crown pea to investigate the effect of enhanced dissolved oxygen and supplemental LED lighting on growth and development of plants grown in a nutrient film technique (NFT) hydroponic system. A 1:1 mix of blue and red LED light units (Phillips) and an electrolysis system (O2Grow) were used to provide the following treatments to supplement standard NFT conditions: 1) Red/Blue LED supplemental lighting; 2) Red/Blue LED lights and enhanced dissolved oxygen (DO); 3) enhanced DO; and 4) control (nutrient solution alone). Overall, plant growth was greatest in the enhanced dissolved oxygen environments. Crown pea plants were taller, branched more, produced nodes faster and had wider apices and more root mass than the control plants and control plants + LED lights. Root growth was also greatest in the enhanced DO + LED light environment. However, the node of flower initiation was highest in the enhanced DO environments (treatments 2 and 3) indicating a delay in flowering. Enhancing the dissolved oxygen content and light environment in NFT hydroponic systems warrants further investigation to determine the effects on plant growth and reproductive development in the crown pea.