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Allelopathy delivers the concept of using allelochemicals elicited from donor plants into environment to influence the survival of receptor plants. Invasive plants having allelochemicals could provide low-cost, abundant and eco-friendly materials for controlling noxious weeds. In spite of that, the direct use of invasive plant extracts encounters major hurdles such as variation of bioactive chemicals not being identified, lack of optimal extraction, inadequate physicochemical properties and poor delivery system resulting in low efficacy of the natural products. This study aims to investigate the phytotoxicity, putative allelochemicals, extraction optimisation, pre-emulsion formulations and water-dispersible powders of the leaf extract of Mikania micrantha Kunth ex H.B.K. against a noxious weed, Echinochloa colona (L.) Link and the impact on productivity of rice plant, Oryza sativa L.. In phytotoxicity study, the leaf, stem and root (except M. micrantha) extracts of nine invasive plant species were evaluated against E. colona. Among the plant extracts, the leaf extract of M. micrantha showed 100% inhibition of germination of E. colona at the concentration of 100 g BDWE/L. The leaf extract was subjected to liquid chromatography-mass spectrometer (LC-MS) analysis to identify phytochemicals with possible inhibitory effect. Joint putative allelochemicals consisting of 16 phenolics and 4 aromatics were detected and protocatechuic acid was found contributed to 15.39% inhibition of germination. The leaves of M. micrantha were processed through extraction optimisation using response surface methodology (RSM). The optimal extraction condition was found at an extraction time of 262 min, a stirring speed of 259 rpm and an aqueous methanol of 95% v/v. In the development of pre-emulsion formulations, three polyalkoxylated fatty alcohol (PAFA)-based mixed surfactants PAFA-AS (alkyl sulfonate), PAFA-CB (cocamidopropyl betaine) and PAFA-APG (alkyl polyglucosides) were used to constr

Allelopathy delivers the concept of using allelochemicals elicited from donor plants into environment to influence the survival of receptor plants. Invasive plants having allelochemicals could provide low-cost, abundant and eco-friendly materials for controlling noxious weeds. In spite of that, the direct use of invasive plant extracts encounters major hurdles such as variation of bioactive chemicals not being identified, lack of optimal extraction, inadequate physicochemical properties and poor delivery system resulting in low efficacy of the natural products. This study aims to investigate the phytotoxicity, putative allelochemicals, extraction optimisation, pre-emulsion formulations and water-dispersible powders of the leaf extract of Mikania micrantha Kunth ex H.B.K. against a noxious weed, Echinochloa colona (L.) Link and the impact on productivity of rice plant, Oryza sativa L.. In phytotoxicity study, the leaf, stem and root (except M. micrantha) extracts of nine invasive plant species were evaluated against E. colona. Among the plant extracts, the leaf extract of M. micrantha showed 100% inhibition of germination of E. colona at the concentration of 100 g BDWE/L. The leaf extract was subjected to liquid chromatography-mass spectrometer (LC-MS) analysis to identify phytochemicals with possible inhibitory effect. Joint putative allelochemicals consisting of 16 phenolics and 4 aromatics were detected and protocatechuic acid was found contributed to 15.39% inhibition of germination. The leaves of M. micrantha were processed through extraction optimisation using response surface methodology (RSM). The optimal extraction condition was found at an extraction time of 262 min, a stirring speed of 259 rpm and an aqueous methanol of 95% v/v. In the development of pre-emulsion formulations, three polyalkoxylated fatty alcohol (PAFA)-based mixed surfactants PAFA-AS (alkyl sulfonate), PAFA-CB (cocamidopropyl betaine) and PAFA-APG (alkyl polyglucosides) were used to constr

Herbicides produce a wide range of toxic side-effects that pose a potential hazard to the environment. The development of natural herbicide is one method of addressing these issues. Tinospora tuberculata is an aromatic shrub with pharmacological properties and belongs to the Menispermaceae family. Herbicidal potential of aerial parts of T.tuberculata on germination and seedling growth of rice (Oryza sativa L.) and two rice weeds, barnyardgrass (Echinochloa crus-galli L.) and weedy rice (Oryza sativa L.complex) were evaluated. Six concentrations of methanol and water extract (3.12, 6.25, 12.5, 25, 50, and 100 g L−1) were compared with the control (distilled water). The magnitude of the phytotoxicity effects at the same concentration levels in the test plants was dependent on the source of the extract (either leaf or stem) and types of solvent (water or methanol). Leaf extract was found to have greater suppressive property than the stem extract and the methanol extracts of leaf and stem were present in higher phytotoxic compared with respective water extracts. The gas chromatography–mass spectrometry (GC-MS) and ultra-fast liquid chromatography (UFLC) analysis confirmed methanol extracts and leaf extracts contained higher number and amount of chemical compounds than did those of the water extracts and stem extracts, respectively. Benzoic acid (highest allelopathic activity) was found in the highest concentration in the methanol leaf extract,while this compound was not identified in the water leaf extract. On the other hand, the predominant compound was orientin (lowest allelopathic activity) from stem extracts. Therefore, the herbicidal activity of each extract (leaf methanol extract, leaf water extract, stem methanol extract, and stem water extract) was dependent on their number, concentration, combination and inhibitory activity of the compounds. In the glasshouse experiments, allelopathic potential of powder and methanol extract of T. tuberculata leaf as pre emerge

Herbicides produce a wide range of toxic side-effects that pose a potential hazard to the environment. The development of natural herbicide is one method of addressing these issues. Tinospora tuberculata is an aromatic shrub with pharmacological properties and belongs to the Menispermaceae family. Herbicidal potential of aerial parts of T.tuberculata on germination and seedling growth of rice (Oryza sativa L.) and two rice weeds, barnyardgrass (Echinochloa crus-galli L.) and weedy rice (Oryza sativa L.complex) were evaluated. Six concentrations of methanol and water extract (3.12, 6.25, 12.5, 25, 50, and 100 g L−1) were compared with the control (distilled water). The magnitude of the phytotoxicity effects at the same concentration levels in the test plants was dependent on the source of the extract (either leaf or stem) and types of solvent (water or methanol). Leaf extract was found to have greater suppressive property than the stem extract and the methanol extracts of leaf and stem were present in higher phytotoxic compared with respective water extracts. The gas chromatography–mass spectrometry (GC-MS) and ultra-fast liquid chromatography (UFLC) analysis confirmed methanol extracts and leaf extracts contained higher number and amount of chemical compounds than did those of the water extracts and stem extracts, respectively. Benzoic acid (highest allelopathic activity) was found in the highest concentration in the methanol leaf extract,while this compound was not identified in the water leaf extract. On the other hand, the predominant compound was orientin (lowest allelopathic activity) from stem extracts. Therefore, the herbicidal activity of each extract (leaf methanol extract, leaf water extract, stem methanol extract, and stem water extract) was dependent on their number, concentration, combination and inhibitory activity of the compounds. In the glasshouse experiments, allelopathic potential of powder and methanol extract of T. tuberculata leaf as pre emerge