Effects of population density on sex expression in Onoclea sensibilis L. on agar and ashed soil

• Published in: Annals of botany 1985-01, Vol.55 (2), p.205-215
• Main Authors: Rubin, G, Robson, D.S, Paolillo, D.J
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; ashing; Biological and medical sciences; Demecology; Density; fern gametophytes; ferns and fern allies; Fundamental and applied biological sciences. Psychology; Gametophytes; Onoclea sensibilis; Onoclea sensibilis L; plant density; Plant growth; Plants; Plants and fungi; Polypodiopsida; Population density; sensitive fern; sex expression; sexuality; soil chemistry; Soil density; Sowing; Spores; Standard error; Thallus
• ISSN: 0305-7364; 1095-8290
• DOI: 10.1093/oxfordjournals.aob.a086893

Population density affected the sex expression of agar-grown gametophytes of Onoclea sensibilis L. The time of onset of sexuality was advanced, the proportion of females was increased, and the growth rate of individuals was greater at lower densities. Population density had no effect on the sex expression of Onoclea grown on ashed soil, and there was no difference in growth rate of individuals grown on ashed soil at different densities. Covariate analysis, using thallus width as a measure of growth rate, indicated that the effect of density on sex expression was mostly associated with growth rate. The differing effects of population density on agar and ashed soil demonstrate that substrate influences sex expression in Onoclea. This influence is most dramatic in single-gametophyte cultures, where agar cultures produced 97 per cent females and ashed soil cultures 100 per cent males.