Investigation on the Allelopathic Impact of Blanket Weed (Galenia secunda) as a Distributed Invasive Weed in Some Natural Grasslands

  • Ako H. Mahmood Department of Forestry, College of Agriculture, Slahaddin University-Erbil, Kurdistan Region, Iraq
Keywords: Allelopathy,Aqueous extracts,Germination,Seedling growth


The broad leaf perennial weed, Galenia secunda forms large colonies that reduced the abundance of native vegetation in many natural grasslands. Although rapid growth and prolific reproduction (both sexual and asexual) clearly contribute to its successful invasion, its might be have a strong allelopathic effects beside the competition capability on native plants. Therefore, we conducted a study to investigate the allelopathic effects of G. secunda weed on seed germination and seedling growth of lettuce (as a model plant test). Stem, root and leaf aqueous extracts of G. secunda at 0, 1, 5, 10, and 15 % concentrations were applied to determine their effect on lettuce seed germination and seedling growth under laboratory conditions. Increasing concentrations of aqueous extracts of G. secunda from leaf and stem inhibited seed germination and greater than 78 % of seeds were failed to germinate when the extract concentration from the leaf part was 15 %. In contrast, aqueous extracts from root had no effect on lettuce seed germination. Extracts from root and stem had a stimulatory effect on shoot length at all concentration levels, as against an inhibitory effect of leaf extracts. Root extracts at low concentration (1 and 5 %) promoted root length but aqueous extracts from leaf and stem inhibited root length. The results from this study show that G. secunda produces chemicals that can inhibit the growth of neighbouring plant species.


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How to Cite
H. Mahmood, A. “Investigation on the Allelopathic Impact of Blanket Weed (Galenia Secunda) As a Distributed Invasive Weed in Some Natural Grasslands”. ZANCO Journal of Pure and Applied Sciences, Vol. 31, no. s4, Oct. 2019, pp. 83-89, doi:10.21271/zjpas.31.s4.14.