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bioRxiv · 10.1101/2023.07.21.550054

Invasive Argemone mexicana's suppressive effects on Phaseolus vulgaris and Zea mays germination and growth

Ojija, F.
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Abstract

Invasive Argemone mexicana plant species is invading many ecosystems in East Africa. However, there have not been many studies to assess how it affects plants. In petri dishes and pot experiments, we investigated the suppressive effects of A. mexicana on Phaseolus vulgaris and Zea mays germination and seedling growth. To investigate its suppressive effects on the test plant, different concentrations of A. mexicana leaf (AmL) crude extract were applied to the seeds and seedlings of P. vulgaris and Z. mays. At higher concentrations (70% and 100%), the findings showed that AmL crude extract concentrations reduced the germination and growth of P. vulgaris and Z. mays seeds. Compared to seeds that germinated at lower concentrations and in the control (0%) group, fewer seeds at higher concentrations grew. Accordingly, higher concentrations, relative to lower ones and controls, retarded seed germination. Additionally, the fresh biomass, root lengths, stem diameters, and heights of P. vulgaris seedlings were reduced under 75% and 100% AmL concentrations, which had a negative impact on their growth vigor. Although this study shows that P. vulgaris and Z. mays germination and growth were inhibited by A. mexicana crude extract, field research experiments are needed to investigate the suppressive effects of this invasive weed on other plant species. Due to its detrimental impact on plant growth, the study recommends further management of A. mexicana to protect biodiversity. It is expected that these results will be helpful in developing policies and programs for managing invasive plants while taking into account the effects on peoples livelihoods.

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Ojija, F.. 2023-07-25. Invasive Argemone mexicana's suppressive effects on Phaseolus vulgaris and Zea mays germination and growth. https://doi.org/10.1101/2023.07.21.550054

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