Wednesday, August 10, 2016
Georgia Ballroom (Sheraton Hotel Atlanta)
Plant growth and subsequent crop harvest is contingent upon sufficient water inputs. Many regions of the world experience persistent or temporal droughts. With a steadily increasing world population, already limited water resources will be spread even thinner, further increasing the pressure to use water more efficiently, especially in plant production. To further investigate the enhancement of water use efficiency in plant production we tested the nonionic surfactant Tween® 20 as an irrigation additive for its potential effects on growth, physiology, and drought tolerance of coleus. Four irrigation treatments were imposed upon coleus plants consisting of (1) water only (control); (2) 100 ppm Tween® 20; (3) 320 ppm Hydretain®; and (4) 100 ppm AquaGro 2000 L. The products Hydretain® and AquaGro are somewhat similar in function to Tween® 20 and are currently used in industry practice which is why they were chosen for comparison. Experiments were conducted in a greenhouse and each of the treatment products were injected into irrigation water using a fertigation system. After one week of growth and data collection, coleus plants were given one final irrigation and then allowed to dry out, simulating drought conditions. After drought induction, we made daily observations on physiological parameters including transpiration, net photosynthesis, stomatal conductance. In preliminary studies, the use of Tween® 20 as an irrigation additive has shown potential to increase water use efficiency in plants by up to 40 percent.