Assessing the Deterrent Effect of Aqueous and Formulated Extracts of Russian Knapweed (Acroptilon repens L.) with Chitosan on the Germination of Rye Weed (Secale cereale L.)

In order to investigate the germination of Rye weed (Secale cereale L.) under the influence of Russian knapweed (Acroptilon repens L.) aqueous and formulated extracts with chitosan, an experiment was conducted as a factorial based on a completely randomized design with three replications in the Agricultural and Natural Resources Faculty laboratory of the University of Mohaghegh Ardabili in 2017. Experimental treatments included the type of extract (Russian knapweed aqueous extract and its formulated extract with chitosan) and seven concentrations of zero (Control), 0.625, 1.25, 2.5, 5, 10, and 20%. The results indicated that rye germination and its related components were significant at the (P≤1%). The formulated Russian knapweed extract at a concentration of 0.625 caused a 15.17% increase in plumule length compared to the control treatment, and the concentrations of 5 and 10% of the formulated extract caused 100% control of the plumule and radicle length compared to the control treatment. The concentration of 0.625 of Russian knapweed aqueous extract was the lowest (10 %) and the concentration of 5 and 10 of the extract formulated with chitosan was the highest (100 %) showed a decrease in the plumule, radicle, and seedling fresh weight compared to the control treatment. Also, the concentrations of 5 and 10 formulated extracts of Russian knapweed reduced 100% plumule, radicle, and seedling dry weight. Increasing the concentration of both types of extract increased the inhibition potential of germination so that in concentrations of 10 and 20% Russian knapweed extract, and formulated extract with chitosan, a significant reduction in rye germination was recorded. Aqueous and formulated extracts of Russian Knapweed with chitosan in concentrations of 10 and 20% are recommended for controlling Rye weed germination in laboratory conditions.