Sebastian Weissbein1, Zeev Wiesman1, Moshe Silberbush2, and Jhonathan Ephrath2. (1) Ben-Gurion University of the Negev, Phyto-Lipid Bitechnology Lab (PLBL),Department of Biotechnology Engineering, Beer Sheva, 84105, Israel, (2) Ben-Gurion University of the Negev, Jacob Blaustein Institute for Desert Research, Wyler Department for dryland Agriculture, Sede Boqer Campus, Midreshet Ben-Gurion, Israel
New olive (Olea
europea L.) orchards are being implanted in many semi arid areas, where
saline water is the main source of water available crop irrigation. Olive is moderately
tolerant to salinity. Still saline effects on olive root development has not
yet described adequately. Plant roots are adapted to
absorb water and nutrients from the soil to provide necessary ingredients for
optimal growth and development of the plant. The function of roots is
profoundly influenced by soil nutrient composition, the presence of toxins and
by biotic and abiotic environmental stresses. In the present study, root development
of olive (cv Barnea) were compared under saline drip irrigation (4.2 dS
m-1) and control (1.2 dS m-1), A minirhizotron (MR) system consisting on a miniature video
camera was used for monitoring root development; Clear acrylate tubes with 52 mm inner and 60 mm outer diameter, were
inserted to the soil at three distances (50, 100 and 150 cm) from the trunk down to
the depth of 2 m. The tubes were installed
on May 5, 2005 and the measurements started one month later. The
observations were taken once a month for 18 months. Soil SAR and Salinity was
measured with depth. Total root number
in the saline treatment was considerably smaller in comparison with the
control. Total root length was larger in olive trees irrigated with freshwater.
Root surface area was smaller in the saline water treatment compared to the
freshwater treatment. Unlike root number and root length, root surface area
continued to increase throughout the observed period in both the treatments.
Root distribution with depth and distance from the trunk varied between the two
water quality treatments. This study suggests that salinity plays an important
role in root distribution and development in olive trees.