Allelopathic effects of some common weeds of Hormozgan province on seed germination and vegetative growth of onion (Allium cepa)
Subject Areas : Journal of Plant Ecophysiology
1 - عضو هیات علمی دانشگاه هرمزگان
2 - استادیار دانشگاه هرمزگان
Keywords: Germination rate, Allelochemical, Amaranthus retroflexus, Dactyloctenium aegyptyum, Leaf chlorophyll content,
Abstract :
In order to investigation of allelopathic activity of aqueous extract and different plant tissues residues of Amaranthus retroflexus, Portulaca oleracea, Chenopodiunm album, Dactyloctenium aegyptyum and Malva neglecta on seed germination and seedling growth of onion, laboratory and pot experiments were performed as a factorial experiment basis of a completely randomized design with three replications in Horticultural science Department of Hormozgan University. In laboratory experiment, studied factors were included five weeds species, six concentrations (0, 1, 2, 4, 8 and 10 ml) of aqueous extract of different tissues (leaf, stem and root) of tested weeds and in pot study, experimental factors included five weeds species, six amounts (0, 1, 2, 4, 8 and 16 gram per pot) of ground residues of different tissues (leaf, stem and root) of studied weeds. Results of this study indicated that in laboratory experiment, A. retroflexus and D. aegyptyum had the most allelopathic effects on onion. Although in most of the studied traits no significant differences were observed between these two weeds, but inhibition effects of A. retroflexus was higher for germination rate, radicel length and dry weight and seedling dry weight. With increase in extract concentrations, almost of onion seedling growth characteristics decreased significantly. Results of pot experiment showed that the weed residues incorporated in soil inhibited the growth and leaf chlorophyll a content of onion. Both A. retroflexus and D. aegyptyum had the maximum inhibition effects on all of onion vegetative growth trails. But A. retroflexus allelopathic effects on seedling emergence percentage and chlorophyll a content were more obvious. Results of this study indicated that since between studied weed species, A. retroflexus and D. aegyptyum had the most allelopathic effects on onion seed germination and vegetative growth characteristics, therefore these two weeds must be controlled completely before onion cultivation.
