Higher Plants

Contamination with 2,4,6-trinitrotoluene (TNT) is widespread at sites of past munitions manufacture. It is moderately toxic to plants and highly toxic to some animals. Some aquatic plant species have been observed to promote degradation of TNT. The degradative activity is associated with the root systems but products are found in the surrounding medium. We have examined a range of sixteen genera of non-aquatic plants grown hydroponically to determine whether the promotion of TNT degradation is a general phenomenon of plant root systems. All tested species showed the ability to reduce TNT extensively. Rates varied several fold when calculated on a wet weight of tissue basis. Isolated roots, disrupted roots, and root extracts generally showed less activity than intact roots attached to the plants. Water in which the plants had been grown did not promote degradation.