Assessing allelopathic potential of Sonchus oleraceus L. (milk thistle) on germination and seedling growth of Oryza puncta

ABSTRACT Aqueous extracts of plants are used to control weeds and having no hazards to environment and are inexpensive. Present study was undertaken to investigate the effect of aqueous extracts of Sonchus oleraceus L. on the Oryza punctata L. emergence and initial seedling growth. It consists of aqueous extract of leaves, stem and fruit of S. oleraceus at varying concentrations 0.25, 0.50, 1, 2, 4 and 8 % (w/v) along with a distilled water control. The allelochemicals present in the aqueous extracts showed stimulatory, inhibitory and hormetic responses depending upon the concentration and the plant part. Results directed that maximum mean emergence time (5.26 days) and minimum germination index (1.67), germination percentage (40%), seedling fresh weight (59 g) and dry weight (8 g) of O. punctata were examined with 8% aqueous extract of S. oleraceus fruit. However, 4% aqueous extract of S. oleraceus fruit produced minimum root length (5.71). On the basis this experiment it was concluded that 8% aqueous extract of S. oleraceus fruit can be used for controlling O. punctata weed. Keywords: Aqueous extract, environment, allelochamicals, hermetic response, stimulatory ABSTRACT Aqueous extracts of plants are used to control weeds and having no hazards to environment and are inexpensive. Present study was undertaken to investigate the effect of aqueous extracts of Sonchus oleraceus L. on the Oryza punctata L. emergence and initial seedling growth. It consists of aqueous extract of leaves, stem and fruit of S. oleraceus at varying concentrations 0.25, 0.50, 1, 2, 4 and 8 % (w/v) along with a distilled water control. The allelochemicals present in the aqueous extracts showed stimulatory, inhibitory and hormetic responses depending upon the concentration and the plant part. Results directed that maximum mean emergence time (5.26 days) and minimum germination index (1.67), germination percentage (40%), seedling fresh weight (59 g) and dry weight (8 g) of O. punctata were examined with 8% aqueous extract of S. oleraceus fruit. However, 4% aqueous extract of S. oleraceus fruit produced minimum root length (5.71). On the basis this experiment it was concluded that 8% aqueous extract of S. oleraceus fruit can be used for controlling O. punctata weed. Keywords: Aqueous extract, environment, allelochamicals, hermetic response, stimulatory ABSTRACT Aqueous extracts of plants are used to control weeds and having no hazards to environment and are inexpensive. Present study was undertaken to investigate the effect of aqueous extracts of Sonchus oleraceus L. on the Oryza punctata L. emergence and initial seedling growth. It consists of aqueous extract of leaves, stem and fruit of S. oleraceus at varying concentrations 0.25, 0.50, 1, 2, 4 and 8 % (w/v) along with a distilled water control. The allelochemicals present in the aqueous extracts showed stimulatory, inhibitory and hormetic responses depending upon the concentration and the plant part. Results directed that maximum mean emergence time (5.26 days) and minimum germination index (1.67), germination percentage (40%), seedling fresh weight (59 g) and dry weight (8 g) of O. punctata were examined with 8% aqueous extract of S. oleraceus fruit. However, 4% aqueous extract of S. oleraceus fruit produced minimum root length (5.71). On the basis this experiment it was concluded that 8% aqueous extract of S. oleraceus fruit can be used for controlling O. punctata weed. Keywords: Aqueous extract, environment, allelochamicals, hermetic response, stimulatory