Abstract:

To explore the competitive relationship between the invasive plants and the native plants, this study used Tagetes minuta and Hordeum vulgare as experimental materials, and adopted the addition series experiment method, to carry out the control experiment in greenhouse by mixing single species and different proportions. The results showed that: (1) interspecies competition reduced the biomass and water content of Tagetes minuta but increased its plant height; the biomass, water content and plant height of Hordeum vulgare were reduced; (2) the relative yield (RY_Tm) of Tagetes minuta was 0.78-0.98, the difference was not significant; the relative yield (RY_Hv) of Hordeum vulgare was 0.09-0.73, the difference was significant; the influence of mixed planting on Tagetes minuta was less than that on Hordeum vulgare; (3) the sum of their relative yield (RYT) of Tagetes minuta and Hordeum vulgare was 0.53-0.86, which indicated the two used common resources and had a competitive relationship; (4) the competitive aggressivity coefficient (A) of Tagetes minuta on Hordeum vulgare was 0.23-0.80, and Tagetes minuta was more competitive than Hordeum vulgare. The study reveals that interspecies competition is more than intraspecies competition when Tagetes minuta and Hordeum vulgare are mixed planted, Tagetes minuta is more competitive than Hordeum vulgare, and could affect the normal growth of Hordeum vulgare.

Key words: Tagetes minuta, Hordeum vulgare, competition, invasion, invasive alien plants, native plants