The plant hormone ethylene (C2H4) may cause an undesirable ripening and senescence of horticultural produce when it accumulates in transport or storage facilities. Therefore, the use of biological catalysts for ethylene removal has recently been tested. It has been found that growing media for potted plants (peat-soil) may consume ethylene, but only after an initial adaptation period. The present data show that the soil water content (2.4 to 4.7 mL g-1 dry wt soil) only plays a minor role for this characteristic. Ethylene consumption in peat-soil can be enhanced, however, by plant growth or the addition of ethylene-oxidizing bacteria. In experiments with Begonia elatior ‘Nielson’ the effect of such ethylene consumption has been tested during conditions of transport simulation (i.e., ethylene exposure in darkness). Although an enhanced ethylene removal was demonstrated, no effects on the plant quality occurred. Thus, the ethylene consumption was insufficient to reduce the ethylene concentration (1 ppm) to levels near the threshold limit for the action of ethylene as a plant hormone (ca. 0.01 ppm). While the consumption of ethylene may be insufficient when a passive scrubber system is applied, the removal of ethylene to extremely low levels is possible by application of a biofilter with ethylene-oxidizing bacteria. By use of a peat-soil biofilter with the bacterial strain RD-4, it was possible to remove ethylene from 2 and 117 ppm to levels as low as 0.017 ppm. These results, as well as results from other biofilters, demonstrate the potential for biological removal of ethylene during storage and transport of horticultural produce.