Abstract
The aim of this investigation was to determine if sorgoleone (SGL), ap-benzoquinone inSorghum bicolor root exudate, is a photosynthesis inhibitor. Assays usingGlycine max leaf disks showed concentrations as low as 10μM SGL inhibited oxygen evolution more than 50%. Tests conducted on chloroplasts isolated fromPisum sativum showed that SGL is a powerful inhibitor of CO2-dependent oxygen evolution. Using a chloroplast suspension equivalent to 80–100μg chlorophyll, the I50 was approximately 0.2μM SGL. These data indicate inhibition of photosynthesis is part of the explanation for growth reduction caused by this allelochemical.
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This study was supported by National Science Foundation grant STI-8902066.
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Einhellig, F.A., Rasmussen, J.A., Hejl, A.M. et al. Effects of root exudate sorgoleone on photosynthesis. J Chem Ecol 19, 369–375 (1993). https://doi.org/10.1007/BF00993702
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DOI: https://doi.org/10.1007/BF00993702