In:
New Phytologist, Wiley, Vol. 112, No. 4 ( 1989-08), p. 533-542
Abstract:
Short‐term exposure of maize, pumpkin, spinach and spruce to various atmospheric H 2 S concentrations resulted in high H 2 S fluxes to the shoots. In all species an almost linear relation was observed between flux and H 2 S concentration up to around 0.3 μl −1 . At higher H 2 S concentrations the flux reached a maximum, which was about 0.08, 0.04, 0.1 and 0.03 μmol g f. wt −1 h −1 for maize, pumpkin, spinach and spruce, respectively. The transpiration rate was not affected during H 2 S exposure. Up to a level of 0.3 μl 1 −1 , the shoot conductance for a influx of the various species varied between 61 and 92% of that predicted from shoot conductance for aqueous vapour efflux. There was no relation between the H 2 S flux to the shoots and the sensitivity of the species towards H 2 S. A 12 days' exposure of maize, pumpkin and spinach to 0.75 μl 1 −1 H 2 S resulted in a reduction of shoot yield of 1.36 and 69%, respectively. H 2 S flux to the shoots of pumpkin, spinach and spruce remained rather constant during exposure for three or four days to about 0.22μl l −l H 2 S. Even at a concentration of about 0.8 μl 1 −1 H 2 , which reduced the growth of pumpkin and spinach, the fluxes remained nearly constant. Fluxes of H 2 S to the shoots did, however, vary diurnally, being high during the light and low during the dark period. The H 2 S flux to transpiration ratio was constant during both light and dark periods, indicating that uptake was predominantly via the stomata. Only part of the total flux of H 2 S to the shoots of pumpkin and spinach could be recovered in the water‐soluble non‐protein sulphydryl fraction of the shoots (maximum 34%). It is proposed that cysteine synthase is directly involved in the fixation and metabolism of atmospheric H 2 S by the plant.
Type of Medium:
Online Resource
ISSN:
0028-646X
,
1469-8137
DOI:
10.1111/nph.1989.112.issue-4
DOI:
10.1111/j.1469-8137.1989.tb00348.x
Language:
English
Publisher:
Wiley
Publication Date:
1989
detail.hit.zdb_id:
208885-X
detail.hit.zdb_id:
1472194-6
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