The Effect of SO₂onLolium perenneL. Grown at Different Levels of Sulphur and Nitrogen Nutrition

Depression of Growth and Yield in Winter Barley Exposed to Sulphur Dioxide in the Field

“…various grasses (Cowling & Lockyer, 1978;Ashenden, 1979;Whitmore & Mansfield, 1983) and of 'Igri' winter barley (Pande & Mansfield, 1985a). We also found winter growth reduction in a single-plot exposure of winter wheat at 100 ppb above ambient in 1981/82 (unpublished data).…”

“…Cowling & Lockyer, 1978), field crops may be especially susceptible to damage during winter. Using a computer-controlled field exposure system, we have exposed commercially-managed winter cereals to SOj throughout the growing season.…”

Uptake and metabolism of sulphur dioxide by Arabidopsis thaliana

“…The powder was mixed with microfine wax (Hoechst Wax 'c', Germany) to a plant material/wax ratio of 1 :80, Plant material and wax were stirred for 5 min with a magnetic stirrer to achieve an homogeneous mixture, A 1-25 g sample of the mixture was pressed with a hydraulic press to a powdered part (diameter 20 mm, height 4 mm). From every mixture two powdered parts were pressed and S content was determined according to Schnug, Murray & Haneklaus (1993), Total N was determined by the Kjeldahl method described by Barneix et al (1988), Organic S (Org-S) and organic N (Org-N) content were estimated by subtracting the corresponding sulphate-S and nitrate-N contents (see anion determination) from the total S and N contents (Cowling & Lockyer, 1978;Huve et al 1995).…”

“…especially if the sulphur supply of the soil is insufficient for normal growth (Cowling & Lockyer, 1978;MaughII, 1979;Schnug & Evans, 1992), The absorbed SO,, might be metabolized and used as a sulphur source for plant growth (Rennenberg, 1984;De Kok, 1990), Plant species with a high demand for sulphur and a high capacity to produce sulphurcontaining secondary metabolites, cruciferous species for instance, might even benefit from elevated levels of SO,, (Ernst, 1993),…”

Effects of sulphur dioxide on leaf photosynthesis: the role of temperature and humidity

“…It has been demonstrated that depressing so2 effects on plant growth were most severe during winter periods, when temperature and irradiance are low and humidity is high (Cowling and Lockyer 1978, Davies 1980, Whitmore and Mansfield 1983, Baker et al 1986. The reported growth reductions are at least partly due to direct effects on photosynthesis and/or respiration, because no strong reductions in leaf area were detected (Whitmore and Mansfield 1983, Baker et al 1986.…”