Search results for " water potential."

Modelling eco-physiological response of table olive trees (Olea europaea L.) to soil water deficit conditions

2013

Abstract The knowledge of crop response to water stress is crucial to predict transpiration reductions under limited soil water conditions and for a rational scheduling of irrigation. In order to assess whatever water stress model, it is necessary to estimate critical thresholds of soil water status, below which plant transpiration starts to decrease. The main objective of the work is to identify the shape and to determine the parameters of table olive orchards (Olea europaea, var. Nocellara del Belice) water stress function, assessed according to relative transpiration or leaf/stem water potential. In order to assess different water stress functions describing the eco-physiological field r…

Establishing a Reference Baseline for Midday Stem Water Potential in Olive and Its Use for Plant-Based Irrigation Management

2021

12 páginas.- 7 figuras.- 4 tablas.- 55 referencias.-

Responses of Prunus ferganensis, Prunus persica and two interspecific hybrids to moderate drought stress

2003

Prunus ferganensis (Kost. & Riab) Kov. & Kost, a close relative of the cultivated peach (Prunus persica (L.) Batsch.), is native to arid regions of central Asia and may possess traits valuable for improving drought tolerance of commercial peach varieties. One distinguishing feature of P. ferganensis is its prominent, elongated, unbranched leaf venation pattern, which behaves as a simple recessive trait in segregating populations of P. ferganensis x P. persica hybrids. To understand whether this trait could be used as a marker in breeding for drought tolerance, we investigated the association between leaf morphological and physiological parameters related to drought response in P. ferganensi…

Leaf water potential meaning of different modalities of measurements

2004

<p style="text-align: justify;">An experiment on Syrah in the Ecotron design of the AGRO Montpellier/INRA campus vineyard, with the control of different water regimes, allowed to test the physiological meaning and the field of application of different modalities of leaf water potential measurements : predawn and daily potential for leaves in a normal micro-environment (which keep all of their interest and generality), « stem » potential (which must be called differently and reserved to particular conditions) for shadow enveloped leaves. Field observations on Syrah and Merlot confirm the interest of some methods.</p>

Growth and physiological responses of young olive trees affected by Olive leaf yellowing associated virus

2017

We studied the effect of Olive leaf yellowing associated virus (OLYaV) on biometric and physiological changes in olive. The trial was carried out on 32 two-yearold virus-free trees of 'Frantoio' grafted on virus-free olive seedlings and grown in 32-L pots. Half of the trees were inoculated with OLYaV in the fall of 2007. At 6, 18, and 24 months after inoculation, tree height, basal trunk diameter and total leaf number were determined, and leaf area tree-1 was estimated from a 50-leaf subsample. Twigs of various order were also counted and measured. At the end of the experiment, dry matter partitioning, leaf gas exchange and water potential were also measured. Total twig length and number, t…

Assessing AQUACROP water stress function to evaluate the transpiration reductions of olive tree.

2012

Quantitative evaluation of the drought adaptation processes of crops is an important prerequisite for efficient irrigation management. Modeling the plant response under water stress conditions is crucial to identify the exact irrigation timing. Assessment of any water stress function requires the knowledge of its shape and then the estimation of critical thresholds of the soil water status, below which a strong reduction of plant transpiration occurs. In this work, the macroscopic approach is used to assess the water stress function implemented in AQUACROP for mature olive tree. In particular, after discussing about the function shape, the critical thresholds of soil water status are propos…

Modeling olive orchard response to water stress and definition of critical thresholds of soil water status.

2011

Agro-hydrological models and field measurements to assess the water status of a citrus orchard irrigated with micro-sprinkler and subsurface drip sys…

2021

Compared to the micro-sprinkler irrigation, traditionally used in citrus orchards, subsurface drip systems (SDS) allow increasing the water use efficiency (WUE); when coupled with water-saving strategies, like regulated deficit irrigation (RDI), further increase of WUE are possible. Combining measurements of soil water content (SWC) and weather data with measurements of midday stem water potential (MSWP) makes it possible to identify irrigation scheduling parameters for the RDI. However, measurements of MSWP are destructive and time-consuming, and also require skilled operators. For all these reasons, the use of the agro-hydrological models, such as the FAO-56 model, can be considered a sur…

Relationship between tree water status and physiology, yield, and fruit quality in the table olive (Olea europaea sativa L.) cultivar ‘Nocellara del …

2012

Although the olive (Olea europaea sativa l.) is considered a xerophytic species, long periods of water stress and high temperatures during summer months can greatly affect plant physiology and productivity. In recent years, the use of plant-based water status indicators have become popular in the study of plant-water relationships and in the design of irrigation programs, particularly midday stem water potential (ψstem). The current trend in the irrigation of olive trees is in the development of Deficit Irrigation (DI) systems whereby the water is applied at a rate which is lower than evapotranspiration needs, resulting in only very small reductions in yield. Rather than working towards min…

Plant-based water stress sensing in two olive cultivars with different physiological responses to drought

2022

A large portion of modern olive plantings is dominated by one main cultivar (‘Arbequina’) planted at super high density (SHD, 1,500 tree ha‑1), leading to a dangerous reduction in olive biodiversity. Very few cultivars have growth and productive patterns that suit the SHD system requirements. Partial intensification and mechanization with several cultivars may represent the safest and easiest alternative. The efficient use of limited natural resources, such as water, in SHD systems, requires precise management. Continuous plant-based sensing is a promising approach to managing water, mainly tested on the cultivar ‘Arbequina’. In this study, we evaluated the sensitivity of two promising indi…