Atmospheric nitrogen deposition on petals enhances seed quality of the forest herb Anemone nemorosa

VANNESTE, T.; SHEVTSOVA, A.; LIIRA, J.; LENOIR, J.; HERMY, M.; HEINKEN, T.; GRAAE, B.J.; DIEKMANN, M.; COUSINS, S.A.O.; COUGNON, M.; CARÓN, M.M.; BRUNET, J.; DE FRENNE, P.; VERHEYEN, K.; ORCZEWSKA, A.; KOLB, A.; HANLEY, M.E.; DECOCQ, G.; CHABRERIE, O.; BLONDEEL, H.

PLANT BIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2018 vol. 20 p. 619 - 626

1435-8603

Elevated atmospheric input of nitrogen (N) is currently affecting plant biodiversity and ecosystem functioning. The growth and survival of numerous plant species is known to respond strongly to N fertilisation. Yet, few studies have assessed the effects of N deposition on seed quality and reproductive performance, which is an important life-history stage of plants. Here we address this knowledge gap by assessing the effects of atmospheric N deposition on seed quality of the ancient forest herb Anemone nemorosa using two complementary approaches. By taking advantage of the wide spatiotemporal variation in N deposition rates in pan-European temperate and boreal forests over 2 years, we detected positive effects of N deposition on the N concentration (percentage N per unit seed mass, increased from 2.8% to 4.1%) and N content (total N mass per seed more than doubled) of A. nemorosa seeds. In a complementary experiment, we applied ammonium nitrate to aboveground plant tissues and the soil surface to determine whether dissolved N sources in precipitation could be incorporated into seeds. Although the addition of N to leaves and the soil surface had no effect, a concentrated N solution applied to petals during anthesis resulted in increased seed mass, seed N concentration and N content. Our results demonstrate that N deposition on the petals enhances bioaccumulation of N in the seeds of A. nemorosa. Enhanced atmospheric inputs of N can thus not only affect growth and population dynamics via root or canopy uptake, but can also influence seed quality and reproduction via intake through the inflorescences.