Differences between ex-situ and in situ germination and seedling establishment in the case of the marsh gladiolus (Gladiolus palustris)

The marsh gladiolus (Gladiolus palustris Gaud.) is a species of community interest in the European Union, and it’s strictly protected by law in Hungary. Survival of its populations is threatened by a number of factors, so thorough knowledge on the biology of the species is required for its conservation and long-time survival. To interpret the data collected in local populations, it is essential to examine the dynamics between age-stage categories and study germination rates of seeds in the populations. For this purpose, ex-situ and in-situ germination biology studies were set up to monitor the development of individuals starting from germination and establish a suitable age-stage categorization system for demographic purposes. During the autumn of 2023, seeds were sown in an open forest and in a meadow (in-situ), and seeds from these sites were sown in containers (ex-situ) at the same time. Germination rates were considerably higher in the ex-situ sowing than in the in-situ experiment for seeds of both origins. Moreover, there were significant differences between the average height (leaf length) of the seedlings. Under in-situ conditions average height was significantly larger in the open forest than in the meadows. There were significant differences between average height of seedlings in the in-situ and ex-situ experiments only during the first measurement, which differences became less pronounced later on.