Allelopathy of aqueous extracts from Rhodomyrtus tomentosa on seed germination and seedling growth of Arabidopsis thaliana (L.) Heynh.

Allelopathic effects of different concentrations of aqueous extracts from different plant tissues of invasive plant Rhodomyrtus tomentosa on the seed germination of Arabidopsis thaliana were studied through indoor petri dish method. The results showed that: (1)The allelopathic effects of aqueous extracts from leaf, stem and root on the seed germination varied much, and the intensity of allelopathic effects of different organs was leafstemroot. (2)The difference of germination rate of A. thaliana reached the significant level between the stem treatment groups of 0.20~0.25 g/mL and control group. The germination rate decreased by 19.52% and 24.58%, respectively. Extreme significances of germination index and vitality index existed between the different concentrations of stem treatment and control group. Whats more, the vitality index of the stem treatment group of 0.05 g/mL decreased by 75.89% compared with control group. (3)The root extracts in all concentrations and the stem extracts in higher concentrations exhibited promoting effect on seedling length, while they presented inhibiting effect on seedling fresh weight. Espacially, the response indexes of seedling fresh weight of 0.05 g/mL stem treatment group reached -0.7077. (4)The leaf extracts had strong comprehensive allelopathy in all concentrations. The stem and root extracts both had the strongest comprehensive allelopathy in the concentration of 0.05 g/mL with the RI of - 0.4511 and -0.2137, respectively. The stem treatment group of 0.25 g/mL showed promoting allelopathy on A. thaliana.