ECOPHYSIOLOGICAL CHARACTERIZATION OF C. SATIVA TREES GROWING UNDER DIFFERENT ALTITUDES

The aim of this work was to compare chestnut growth (cv.
Judia) during the year of 2007 at different altitudes (450, 600, 700, 850 and 1050 m a.s.l.). Concerning daily mean photosynthesis rate, highest rate was measured at 1050 m a.s.l., 21.8°C, 11.3 μmol.CO₂.m^-2.s^-1, and the lowest one was 7.6 μmol.CO₂.m^-2.s^-1 determined in the lowest altitude (29.5°C). Data also indicates a variation in photosynthetic pigment composition, showing an increase in Chla/Chlb from 3.1 to 3.7, respectively at 1050 and 450 m a.s.l.
Contrarily a deacrease in Chl/Car was observed.
Moreover, unsaturation index increased as an altitude manner. while lipid peroxidation increased with the altitude.
Leaf water potential, increased from 450 m a.s.l., -1.4 MPa, to 1050 m a.s.l., -0.81 MPa.
Highest fruit size was found at 700 m a.s.l. with 50 fruits/kg, but it must be underlined that percentage of aborted fruits increased for altitudes above the 600 m a.s.l. from 20 until 100% yielded in the 1050 m a.s.l. orchard and below 600 m a.s.l., being 70%.

IV International Chestnut Symposium

J. Gomes-Laranjo, P. Almeida, J. Ferreira-Cardoso, F. Peixoto

Castanea sativa Mill., gas exchanges, water relations, thermic stress, irradiation

https://doi.org/10.17660/ActaHortic.2009.844.16