Revista Chilena de Historia Natural 80 (4): 479-491, 2007
RESEARCH ARTICLE
Response to water deficit of Nothofagus dombeyi plants inoculated with a specific
(Descolea antarctica Sing) and non-specific (Pisolithus tinctorious (Pers.) Coker & Couch)
ectomycorrhizal fungi
The influence of the specific Descolea antarctica (Da) and the
non-specific Pisolithus tinctorious (Pt) ectomycorrhizal fungi on some physiological leaf parameters of the
Chilean evergreen Nothofagus dombeyi subjected to a low soil water potential (-1.6 to -1.9 MPa in a growth chamber for
35 days) and a high water potential (-0.07 to -0.09 MPa, control) was studied. Drought decreased the water status and increased
carbohydrates in mycorrhizal and non-mycorrhizal plants, appearing Da-mycorrhizal and non mycorrhizal plants
better osmotically adjusted (OA= 0.60 MPa and 0.52 MPa, respectively) than Pt-mycorrhizal (0.39 MPa). Proline is not
involved in the OA of mycorrhizal plants. The inoculation of N. dombeyi with both ectomycorrhizal fungi favored a better
maintenance of the functionality of the photosynthetic apparatus under drought as indicated by the effective quantum yield (FPSII). It is concluded that both ectomycorrhizal and non-mycorrhizal N. dombeyi
plants responded to water deficit with OA adjustment, having Da-mycorrhizal plants a greater OA than
Pt-mycorrhizal plants.
Key words:
Nothofagus
dombeyi, ectomycorrhizal fungi, water deficit, osmotic adjustment, photochemical performance of the PSII
