Leucaena leucocephala leachate compromised membrane integrity, respiration and antioxidative defence of water hyacinth leaf tissues

Abstract

BackgroundWater hyacinth is an invasive aquatic weed in many regions of the world. In this study, the bioherbicidal potential of allelopathic plant Leucaena leucocephala against water hyacinth was investigated using a leaf disc assay.ResultsL. leucocephala leachate enhanced electrolyte leakage from water hyacinth leaf discs in a concentration-dependent manner. Control experiments eliminated the possibilities that increased membrane permeability in the leachate-treated leaf discs was due to pH or osmotic effects of the leachate. Thus, the loss of membrane stability in the leachate-treated leaf discs was likely due to phytotoxins detected in the leachate, namely mimosine and phenolic constituents. Decline in tissue respiration was detected in leachate-treated water hyacinth leaf discs. This suggests that the L. leucocephala leachate may contain compounds which acted as respiratory inhibitors. Enhanced reactive oxygen species production coincided with inhibition of catalase and ascorbate peroxidase activities in the leachate-treated water hyacinth leaf tissues. The injurious effects of L. leucocephala leachate on water hyacinth leaf discs probably involved direct inhibition of antioxidant enzymes in addition to direct involvement of some allelochemicals in reactive oxygen species formation.ConclusionIn summary, the toxic effects of L. leucocephala leachate on water hyacinth leaf discs likely lay in its ability to effectively compromise the membrane integrity, tissue respiration and antioxidant defence of the latter.Electronic supplementary materialThe online version of this article (doi:10.1186/1999-3110-54-8) contains supplementary material, which is available to authorized users.

Screening of Allelochemicals in Miscanthus sacchariflorus Extracts and Assessment of Their Effects on Germination and Seedling Growth of Common Weeds

“…In other studies, gallic and caffeic acid have been shown to generate ROS in cells [ 105 , 106 ]. These reactive oxygen species effectively inhibit the activity antioxidant enzymes (including CAT and APX), causing oxidative stress in the cell [ 107 ]. Regeneration of ROS may surge as a result of this.…”

Phytotoxic potential of Senna occidentalis (L.) Link extracts on seed germination and oxidative stress of Ipê seedlings

“…Chai et al . () observed that the phenolic compounds present in lixiviates of Leucaena leucocephala (Lam.) de Wit.…”

…Fell Upas Sits, the Hydra-Tree of Death †, or the Phytotoxicity of Trees

“…Leaf disc assay with Eichhornia crassipes (Mart.) Solms., an invasive aquatic weed in many regions of the world, showed that leaf leachate of L. leucocephala enhanced electrolyte leakage, decline mitochondrial respiration and inhibits antioxidant enzymes in treated tissues [83].…”

“…Flavonoids are known to be a class of allelochemicals that effectively block mitochondrial functions [217]. Multiple physiological disorders, including mitochondrial one, observed in Eichhornia crassipes leaf disks treated by leachate of L. leucocephala imply the combined effect of several phytotoxic compounds on multiple target sites at multiple cellular levels [83].…”