Effect of light, gibberellic acid and nitrogen source on germination of eight taxa from dissapearing European temperate forest, Potentillo albae-Quercetum

Abstract

Little is known about how light affects seed germination and revegetation of species of thermophilous oak forest. To reveal this relationship effects of white, red, far-red irradiations and dark incubation on germination of eight Potentillo albae-Quercetum taxa were examined. Attempts were also made to evaluate the influence of gibberellic acid and different nitrogen sources on the germination characteristics. Interaction between light and nitrogen was also studied. Freshly matured seeds of all taxa germinated very poorly, indicating presence of primary dormancy. Germination rates increased after wet-stratification treatment and were low in darkness. The highest concentration of the nitrogenous solutions that resulted in high germination level was 10 mM, whereas higher concentrations had a negative effect. Nitrate had the strongest influence which can be proved by a ‘gap detection’ mechanism for gaps in the vegetation. Far-red and red irradiation showed antagonistic effect on seed germination. There was a decrease in germination when far-red was followed by red and an improvement when red was followed by far-red treatment. Under red light, gibberellic acid enhanced germination of positively photoblastic taxa. It was concluded that light factor, associated with vegetation gaps, was the most important signal stimulating germination of the studied taxa.

Nitrogen signals and their ecological significance for seed germination of ten psammophilous plant species from European dry acidic grasslands

“…Podzols). Similar conclusion was drawn regarding some woodland species from Spain [ 14 ] and some species from temperate thermophilous oak forest [ 40 ]. Only a few of the species we studied ( C .…”

Direct effects of nitrogen addition on seed germination of eight semi‐arid grassland species

“…In our study, the mean FGP of all species showed a hump-shaped pattern for the focal species. The optimal concentration of the nitrogenous solutions for germination was 10 mM, whereas higher concentrations had a lower effect (Kolodziejek et al, 2017). We found that low nitrogen concentration promoted seed germination, such as for P. bifurca, P. asiatica, and S. viridis, with no negative effect under high nitrogen concentrations.…”

Nitrogen addition decreases seed germination in a temperate steppe

“…Moreover, previous studies have reported that light competition is a major driver of species loss following nutrient enrichment (DeMalach, Zaady, & Kadmon, 2017;Grace et al, 2016;Harpole & Tilman, 2007). The amount of light affecting the undergrowth is a principal condition controlling seed germination and seedling survival (Kolodziejek, Patykowski, & Wala, 2017). An experiment to explore the effects of the amount of light on seeds from different functional groups should be performed in the future.…”