Dose-response studies with ethylenediurea (EDU) and radish

Clover as an indicator plant for phytotoxic ozone concentrations: visible injury in relation to species, leaf age and exposure dynamics

“…The protective effect of EDU against ozone injury observed earlier (Carnahan, Jenner & Wat, 1978;Kostka-Rick & Manning, 1993;Lee & Chen, 1982) was confirmed in the present study. In Experiment 3 it was clearly shown that EDU protected the plants from visible ozone injury, since the degree of injury with and without EDU in the CF treatment was similar to that in EDU treated plants in the NF treatment.…”

“…injury (Carnahan, Jenner & Wat, 1978), but it can also affect the plant growth negatively (Lee & Chen, 1982;Kostka-Rick & Manning, 1993) and differences in yield hetween treated and untreated plants can not he used for the direct assessment of yield loss due to ozone. EDU has been used in the present study and within the UNECE Co-operation primarily to reduce the development of visible ozone injury.…”

Ethylene-di-urea (EDU), an effective phytoproctectant against O₃ deleterious effects and a valuable research tool

“…Hassan et al (1995) in filtered air, semi-open-top chambers with loamy clay soil found no difference between 0 and 500 mg L -1 EDU soil drenches (every 10 days; 3 replications) in root, shoot, and total dry masses and root:shoot ratio of Raphanus sativus L. and Brassica rapa L. plants. Kostka-Rick and Manning (1993b) found that increasing EDU dose altered the plant hypocotyl, root, and shoot dry masses and sink:shoot ratio of radish plants. In a similar dose-response study with bean, Kostka-Rick and Manning (1993c) observed EDU foliar symptoms and considerably reduced pod dry weight due to increasing doses of EDU.…”

“…Repetition of EDU application to soil may result in uneven or unpredictable rates of EDU release from organic matter (Manning et al 2011). A dilemma occurs here: (a) reduce the concentration over time as to avoid any overestimated dosage (due to organic matter release), Hoshika et al 2013Tiwari and Agrawal, 2009Paoletti et al 2008Hoshika et al 2013Varshney and Rout, 1998Elliott et al 1987Long and Davis, 1991 Kostka-Rick and Manning, 1993bKostka-Rick et al 1993Kostka-Rick and Manning, 1993bCannon et al 1993Kostka-Rick and Manning, 1993aTiwari et al 2005 Ainsworth and Ashmore, 1992 Pleijel et al 1999Tiwari et al 2005Elliott et al 1987Pleijel et al 1999Tiwari et al 2005Elliott et al 1987 or (b) increase the concentration over time, especially in woody plants, because plants will have much higher proportion of biomass to supporting organs. This is an important issue that needs to be separately studied in order to better understand the organic matter influence on EDU antiozonate activity.…”

“…Manning et al (2003) concluded that EDU would be an appropriate tool to assess the O 3 effects on established native plants for long-term studies, but with careful dose-response studies prior to field assessments (Kostka-Rick and Manning, 1993b). Although the current evidence is not enough to draw conclusions for the EDU mode of action, the scientific community should continue to setup new experiments in the coming years.…”