Influence of light on pectic enzymes in root exudates of Trifolium alexandrinum inoculated with Rhizobium trifolii.

An in vitro experiment was conduced under bacteriologically controlled conditions to examine the effect of light on the production of pectin methyl esterase (PME) and pectin polygalacturonase (PG) in the root exudates of Trifolium alexandrinum inoculated with an efficient strain of Rhizobium trifolii. The results revealed that PME and PG increased with an increase in the duration of light to which plants were exposed. However, both the enzymes were detected in the root exudates of nonphotosynthesizing plants.