Effect of H2S Fumigation on Water-Soluble Sulfhydryl Compounds in Shoots of Crop Plants

Summary Long-term exposure of Spinacea oleracea and Beta vulgaris to 30, 100 and 300 ppb H 2 S resulted in reduced plant growth at 300 ppb and in an increased water-soluble sulfhydryl-compound content of shoots, even at an exposure to 30 ppb H 2 S. The increase in water-soluble sulfhydryl compounds was noticed during the entire 44 day fumigation period, in spite of ageing of the plants which caused a decrease of the actual sulfhydryl content of the control plants. The increase of sulfhydryl content in spinach was due to an accumulation of glutathione. Already after three days of exposure to 250 ppb H 2 S, the glutathione level in the shoot was increased more than four-fold. The significance of glutathione accumulation during H 2 S exposure for plant metabolism and growth is discussed.