Articles
Use of a plant microtensiometer to improve water productivity in deficit-irrigated sweet cherry trees under Mediterranean climate conditions
Article number
1457_83
Pages
661 – 668
Language
English
Abstract
Regulated deficit irrigation (RDI) is a sustainable practice that improves water use efficiency in fruit orchards.
Although several studies have found consistent and positive effects of this practice, RDI requires frequent measurement of plant water stress (i.e., stem water potential). The pressure chamber (PC) has been the most reliable device for measuring stem water potential (SWP) for decades.
However, the PC requires a well-trained operator and cannot provide continuous measurements of SWP. Recently, a plant microtensiometer (MT) has been successfully introduced in horticulture to estimate SWP continuously in several woody plants.
Nevertheless, there is little information on the application of this device to manage RDI in commercial fruit orchards.
A study was conducted in a commercial sweet cherry orchard for two consecutive years to determine stem water potential (SWP) thresholds for improving water productivity in deficit-irrigated plants using a plant microtensiometer (MT). MT SWP estimates are strongly correlated with PC SWP measurements (R2=0.81, p-value<0.05) for a SWP range between -1.8 and -0.4 MPa.
Moderate and severe RDI-induced reductions in stomatal conductance and Fv/Fm were observed, but these changes did not affect parameters indicative of early defoliation, such as intercepted solar radiation, leaf area index, and normalized difference vegetation index.
Leaf stomatal conductance decreased by 50% when SWP estimates were close to -1.3 MPa, validating this SWP threshold as a physiological limit for moderate RDI. However, the most severe RDI was the only treatment that improved water productivity compared to the wet control (30%). These results confirm that the MT is a reliable tool for monitoring SWP in water-conserving irrigation practices aimed at improving water productivity.
Although several studies have found consistent and positive effects of this practice, RDI requires frequent measurement of plant water stress (i.e., stem water potential). The pressure chamber (PC) has been the most reliable device for measuring stem water potential (SWP) for decades.
However, the PC requires a well-trained operator and cannot provide continuous measurements of SWP. Recently, a plant microtensiometer (MT) has been successfully introduced in horticulture to estimate SWP continuously in several woody plants.
Nevertheless, there is little information on the application of this device to manage RDI in commercial fruit orchards.
A study was conducted in a commercial sweet cherry orchard for two consecutive years to determine stem water potential (SWP) thresholds for improving water productivity in deficit-irrigated plants using a plant microtensiometer (MT). MT SWP estimates are strongly correlated with PC SWP measurements (R2=0.81, p-value<0.05) for a SWP range between -1.8 and -0.4 MPa.
Moderate and severe RDI-induced reductions in stomatal conductance and Fv/Fm were observed, but these changes did not affect parameters indicative of early defoliation, such as intercepted solar radiation, leaf area index, and normalized difference vegetation index.
Leaf stomatal conductance decreased by 50% when SWP estimates were close to -1.3 MPa, validating this SWP threshold as a physiological limit for moderate RDI. However, the most severe RDI was the only treatment that improved water productivity compared to the wet control (30%). These results confirm that the MT is a reliable tool for monitoring SWP in water-conserving irrigation practices aimed at improving water productivity.
Publication
Authors
A. Calderón-Orellana, A. Olivos, M. Calderón-Orellana, P. Puentes, N. Hermosilla
Keywords
Regulated deficitirrigation (RDI), plant water stress, stem water potential (SWP), Leaf stomatalconductance, water-conserving irrigation practices
Online Articles (96)