Partial rootzone drying and deficit irrigation increase stomatal sensitivity to vapour pressure deficit in anisohydric grapevines

Abstract

The aim of this study was to investigate how alternative irrigation strategies affected grapevine (Vitis vinifera L.) stomatal response to atmospheric vapour pressure deficit (VPD). In two sites, application of partial rootzone drying (PRD) at 90–100% of crop evapotranspiration (ETc) increased stomatal sensitivity of Shiraz (Syrah) grapevines to high VPD compared with control vines irrigated with the same amount of water but applied on both sides of the vine. PRD significantly reduced vine water use (ESF) measured as sap flow and in dry conditions increased the depth of water uptake from the soil profile. In both experiments, PRD reduced vine water use by up to 50% at moderate VPD (~3 kPa) compared with control vines irrigated at the same level. In the same vines, the response to PRD applied at 100% ETc and deficit irrigation applied at 65% ETc was the same, increasing stomatal sensitivity to VPD and decreasing sap flow. Hydraulic signalling apparently did not play a role in changing stomatal sensitivity as there was no difference in stem water potentials between any of the treatment (PRD and DI) and control vines. This suggests that a long distance root-based chemical signal such as ABA may be responsible for the changes in stomatal behaviour. Shiraz grapevines have previously been classified as anisohydric-like, but application of PRD and DI increased stomatal closure in response to conditions of high evaporative demand making the vines behave in a more isohydric-like manner.

Improving water use efficiency of vineyards in semi-arid regions. A review

“…In general, no differences have been observed in g s between partial root zone drying and deficit irrigation strategies when the same amount of water was applied to the soil (Sadras 2009). However, the dependency of g s to vapor pressure deficit can be changed under partial root zone drying or deficit irrigation as demonstrated by Collins et al (2010), likely due to different g s regulation by abscisic acid.…”

“…However, this effect was dependent on the soil type or soil water content where grapevines were grown (Collins et al 2010). Root growth rates under partial root zone drying conditions can change the proportion of roots in a drying soil having implications for abscisic acid synthesis, water extraction, and also nutrient uptake.…”

“…In Table 4 (Table 4). In fact, it has been shown by different studies that the same cultivar can behave different significantly with water economy parameters being qualified as iso-or anisohydric cultivar along the growing season (Poni et al 1993) or between experimental years or by changing the irrigation strategy (Collins et al 2010). Therefore, the classification of cultivars in two different categories, iso-and anisohydric behaviors, based on the different g s behaviors related to water potential, is not always helpful, as reported in different comparisons (Chaves et al 2010;Pou et al 2012;Tomás et al 2014a).…”

Phenotyping of Plants for Drought and Salt Tolerance Using Infra-Red Thermography

“…For the selection of the salt-tolerant plants, both conventional low-throughput physiological approaches and modern high-throughput phenotyping approaches have been used. Scientists need to correlate these two approaches and to homogenize the protocol for examining adequate phenotypes under salt stress that might have some role in the regulation of plant temperature (Merlot et al 2002;Jones et al 2009;Collins et al 2010;Munns et al 2010). Stomatal regulation and plant water status are important aspects in the presence of salt stress.…”

Drought effects and water use efficiency: improving crop production in dry environments

“…This can be achieved by adjusting crop phenology to its environment or by using agronomic practices aiming at an improved water use such as deficit irrigation. A variety of approaches have been particularly successful in the irrigation of top fruit and vineyards (Chaves et al 2007;Fereres and Soriano 2007;Beis and Patakas 2010;Collins et al 2010;Lovisolo et al 2010) but also in annual crops (Kang and Zhang 2004;Dodd et al 2006;Kirda et al 2007;Wang et al 2010). In addition to minimising changes in shoot water status, deficit irrigation enhances the balance between fruit and vegetative growth (Davies et al 2002;Chaves and Oliveira 2004).…”