The Effect of Sulphur Dioxide on the Growth of Lolium perenne L.,Lolium multiflorumLam.,Dactylis glomerataL., andPhleum pratenseL.

Abstract

Lockyer, D. R. 1985. The effect of sulphur dioxide on the growth of Lolium perenne L., Lolium multiflorum Lam., Dactylis glomerata L., and Phleum pratense L.¯J. exp. Bot. 36: 1851-1859. Four agriculturally important grasses, Lolium perenne L., Lolium multiflorum Lam., Dactylis glomerata L. and Phleum pratense L. were exposed to sulphur dioxide (SO2) in a system of exposure chambers. The plants were exposed for a total of 43 d to mean concentrations of SO2 in the air of 0,87 or 448 (μg m−3 and herbage was harvested twice. All four grasses showed chlorotic lesions after exposure to the highest concentration of SO2. The effect of SO2 on the yield of herbage was statistically significant only at the second harvest and at the highest concentration; the dry weights of shoots of D. glomerata and L. perenne were reduced by 33% and 16% respectively. Significant effects of SO2 were also found on the 'transpiration coefficients' measured for D. glomerata and P. pratense. The grasses differed in their uptake of sulphur from the atmosphere but this was not related to their sensitivity to SO2. Total–S concentration in the shoots of L. perenne, L. multiflorum and D. glomerata increased almost linearly in response to increasing SO2 concentration; with P. pratense only the highest SO2 concentration raised total-S above the level in control plants. These increases were almost entirely due to the accumulation of sulphate–S.