Assessment of allelopathic plants for their herbicidal potential against field bindweed (Convolvulus arvensis)

Abstract

This study was conducted to examine the allelopathic potential of Crocus sativus, Ricinus communis, Nicotiana tabacum, Datura inoxia, Nerium oleander and Sorghum vulgar on germination and growth of field bindweed (Convolvulus arvensis). In the laboratory experiment, aqueous extracts of plants in various concentrations (2.5, 5.0, 7.5, 10.0 g L-1) were used to determine their effects on germination and growth of field bindweed seedling. In other experiments, the effects of 10 g L-1 aqueous extract and 0, 1, 2 and 4 t ha-1 powders of all the tested species were used in two different pot experiments to determined their allelophatic potentials on plant height, dry weight, number of survivor plant, leaf area, chlorophylls (a, b and total) and carotenoid contents of field bindweed. Results showed that aqueous extracts of R. cummunis, N. tabacum, D. inoxia and S. vulgar significantly (p<0.05) inhibited germination and seedlings growth of field bindweed and the effects were concentration specific; as the concentration of extracts increased the allelopathic effects were more pronounced. Application of 10 g L-1 aqueous extracts of all tested species significantly (p<0.05) reduced all of measured traits, but their effects depended on the species type. Besides, all of the powder treatments influenced the measured parameters including dry weight, height, leaf area as well as chlorophyll and carotenoid contents. The results demonstrated that both aqueous extracts and powders of tested species could be used as post emergence bioherbicides against field bindweed. ?? 2013.