The Effect of Temperature on Seed Germination and Seedling Growth of Two Invasive Plants in Rorippa

Aims: By studying the response of seed germination and seedling growth of invasive plants, Rorippa amphibia and Rorippa sylvestris, to temperature, the influence of temperature on the invasive ability of two species of Rorippa were further analyzed, which provided a theoretical basis for revealing the diffusion and invasion mechanism of two invasive plants in Rorippa.

Study Design: Seed germination and seedling growth test of two invasive plants in Rorippa at different temperature was studied by means of laboratory culture. The germination percentage, germination index, germination potential of the seeds and the total leaf number, root length, lateral root number, biomass and root shoot ratio of seedlings were determined.

Place and Duration of Study: Seeds were collected from the Shenyang Agricultural University of Liaoning Province in July 2018. Experiments were done in the College of Bioscience and Biotechnology, and conducted in April 2019 for a month.

Methodology: The petri dish method was used at the experiment of seed germination. The seedling growth experiment was carried out by pot sowing.

Results: At the seedling stage.R. amphibia has the strongest tolerance at 30°C, while the R. sylvestris does at 35°C. The low temperature is more beneficial to the accumulations of the seedlings, R. amphibia is the most tolerant at 25°C, and R. sylvestris is at 30°C at the seedling stage.

Conclusion: The response of the seeds and seedlings of the two species to temperature was basically the same. Higher temperature promoted seed germination and inhibited seedling growth, while lower temperature inhibited seed germination. The response of seeds and seedlings of R. sylvestris to high temperature makes it more invasive in the process of global warming.