https://doi.org/10.22268/AJPP-39.3.181188

The investigation was completed in the year 2020 in farm and laboratories of Agriculture faculty and the central laboratory (College of Sciences) - Damascus University to study the effect of hexane extract of Sorghum bicolor L., Medicago sativa L., Cynodondactylon L. on growth of three species of weeds: Setariaviridis (L.) Beauv, Urtica urens L and Diplotaxiserucoides (L.) DC. The chemical analysis of these plant extracts which used in integrated weed control programs was done to find out the most important active substances present in these extracts, using a gas chromatography device attached to a mass spectrometer (GC-MS). The extracting the active substance from plants done by means of soxholet extractor, using absolute pure organic solvent, Hexane. The results showed that the superiority of S. bicolor extract in controlling the studied weed species, with controlling efficacy (77.4%) for the U. urens. While the most sensitive weed was S. viridis (L.), for plant height(12.7 cm) and the percentage of dry matter (5.79%) compared to the control.

Nine substances were found in the S. bicolor extract with highest percentage of Neophytadiene 32.045%, and nine substances in M. sativa extract with the highest percentage of Phytol, 28.23%, while 14 compounds were found in the C. dactylon extract with percentage of Propanoic acid 17.55%, however this work was done for the first time in Syria