INVESTIGADORES
GUNDEL Pedro Emilio
artículos
Título:
Neotyphodium fungi effects on Lolium multiflorum seed germination in relation to water availability.
Autor/es:
GUNDEL, P.E.; MASEDA, P.H.; VILA-AIUB, M.M.; GHERSA, C.M. & R.L. BENECH-ARNOLD.
Revista:
ANNALS OF BOTANY
Editorial:
Oxford Journals
Referencias:
Año: 2006 vol. 97 p. 571 - 577
ISSN:
0305-7364
Resumen:
Background
and Aims: Temperate endophyte-infected (Neotyphodium sp.) grasses have been
shown to exhibit an ecological advantage over endophyte-uninfected grasses
under abiotic stressful conditions. It is predicted that endophyte-infected
plant populations will display higher rates of germination and proportion of
germinated seeds under limiting water conditions.
Methods:
The hydrotime regression model was used to describe the effect of Neotyphodium
endophyte on seed germination of Lolium multiflorum at different water
potentials. Additionally, seed mortality after water stress exposure was
estimated in endophyte-infected and -uninfected seeds.
Key Results:
Endophyte infection inhibited seed germination at all water potentials. The
hydrotime model described satisfactorily the germination responses, and
revealed that endophyte-free seeds exhibited higher rates of and final
percentage germination, probably due to a lower base water potential compared
with endophyte-infected seeds. However, Neotyphodium endophyte conferred a
higher rate of survival in those seeds that remained ungerminated when exposed
to highly water stress conditions.
Conclusions:
Changes produced by Neotyphodium endophyte in L. multiflorum seeds might affect
fitness in particular ecological scenarios. For example, the presence of the
endophyte may curtail seed germination when water is limiting, reducing the
risk of seedling death. Conversely, endophyte-free seeds would display an
enhanced germination, ensuring a more rapid seedling establishment if later
water conditions do not restrict plant growth.