Experiments on the effects of Soil depth and sunlight transmitted through a leaf on seed germination of the wild plant Plantago virginica L.

Abstract

In this paper, an experimental study on the effects of light conditions in natural environment on the seed germination of Plantago virginica L. is described. The study found that germination occurred in the majority of seeds that had been buried in a thin layer of soil (2.5mm in depth) under ariticial illumination. In terms of light exposure, seed germination from the soil surface layer was suppressed by of irradiation of sunlight transmitted through the green leaf of an Indian rubber tree for 3 minutes. However, the germination was not suppresed by sunlight transmitted through the rubber tree’s albino leaf, nor through a yellowish or dead banana leaf. Through such experiments, it can be suggested to students that under a green leaf canopy, transmitted sunlight includes far-red light at a higher ratio which suppresses the germination of photoblastic seeds. Such experiments will contribute to better student understanding of plant life and light action in a natural environment.