%0 Journal Article 
%A Torrecillas Melendreras, Arturo
%A Galego, R.
%A Pérez Pastor, Alejandro
%A Ruiz Sánchez, María C.
%T Gas exchange and water relations of young apricot plants under drought conditions
%D 2006
%@ 0021-8596
%U http://hdl.handle.net/10317/983
%X Potted 1.5-year-old apricot plants (Prunus armeniaca L.), growing under
polycarbonate glasshouse conditions with a cooling system, were subjected to
two successive water stress/recovery periods until pre-dawn leaf water
potential (Ypd) reached values between -2.0 and -2.5 MPa, during summer
1996. Control plants were irrigated daily to maintain the soil matric potential at
c. -20 kPa. Water stress limited plant growth and induced a significant
reduction in leaf area, caused by mature leaf abscission. The parallel
behaviour of leaf turgor potential and epinasty in stressed plants indicated that
these movements are turgor-dependent. Osmotic adjustments of 0.27 and
0.60 MPa were observed at the end of the first and second stress period,
respectively. Relative apoplastic water content (RWCa) values were high,
ranging from 27 to 42%, and were not affected by water stress. The rapid
decrease in leaf conductance (gl) from the beginning of the stress periods,
together with the delay in stomatal reopening after rewatering the plants,
indicated that stomatal behaviour was not a simple passive response to water
deficits. Net photosynthesis decreased only at the end of both stress periods
and recovered quickly. These observations indicate that leaf productivity may
be affected only slightly by short-term water stress. The results indicate that
drought resistance in apricot is based mainly on avoidance mechanisms, such
as stomatal control, epinasty and limitation of transpiration by reducing leaf
area. However, some tolerance characteristics, including osmotic adjustment,
high RWCa and low leaf osmotic potential at turgor loss point (Ytlp) values were
observed.
%K Producción Vegetal
%K Apricot trees
%K Water stress
%K Glasshouse
%K Cooling system
%K Albaricoquero
%K Estrés hídrico
%K Invernadero
%K Sistema de refrigeración
%~ GOEDOC, SUB GOETTINGEN