Irrigation schedule on table grapes by stem water potential and vapor pressure deficit allows to optimize Water Use

Abstract

SUMMARYThis study tested the relationship between stem water potential (ψ stem ) and vapor pressure deficit (VPD) in order to evaluate its use as reference for irrigation control of table grape (Vitis vinifera) cvs. Thompson Seedless and Redglobe. Two trials were carried out on consecutive seasons. In the first season the treatments consisted of four different irrigation regimes: T1, plants irrigated at 100% of ETc; T2, irrigated until fruit set the same as T1 but after fruit set every other time T1; T3, plants with no irrigation from fruit set to harvest; and T4, plants irrigated at 50% of ETc throughout the growing season. Vines from T1 always showed a higher ψ stem for a wide VPD range, therefore the ψ stem and VPD relationship was established using T1 vines, obtaining a logarithmic function with a high determination coefficient (R 2 =0.85). The following season this relationship was used to control irrigation frequency on two table grape cvs. Irrigation started when vines had 20 cm shoots and then the irrigation amount was set to replenish 10% of soil available water. Trial 1 was conducted on cv. Thompson Seedless and consisted of two treatments: T1 plants irrigated to satisfy 100% ETc and T2 plants irrigated according to the previously obtained ψ stem -VPD reference line. Trial 2 was established with Redglobe cv. plants using three treatments: T1 plants irrigated to satisfy 100% Etc; T2, plants irrigated the same as T1 but after fruit set every other time T1; and T3, plants irrigated according to the ψ stem -VPD reference line previously obtained. Irrigation frequency determined using the ψ stem -VPD relationship reduced total water volume compared to T1 on both trials, with no effects on yield or quality, showing the feasibility of using this relationship to control irrigation frequency. RESUMOEste trabalho incidiu na análise da relação entre o potencial hídrico xilemático (ψ stem ) e o déficit de pressão de vapor (VPD), para utilizá-la como referência na programação de irrigação em uva de mesa (Vitis vinifera) das variedades Thompson Seedless e Redglobe. Foram realizados dois ensaios em temporadas consecutivas. Na primeira temporada os tratamentos consistiram em quatro regimes de irrigação: T1, plantas irrigadas com 100% de ETc; T2, plantas irrigadas igual ao T1 até a frutificação e depois uma vez a cada duas irrigações deT1: T3, plantas sem irrigação entre a frutificação e a colheita; e T4, plantas irrigadas com 50% de ETc durante toda a temporada. As plantas de T1 apresentaram sempre valores mais altos de ψ stem para uma ampla gama de VPD, portanto, a relação ψ stem -VPD foi estabelecida utilizando plantas de T1, obtendo uma função logarítmica com um alto coeficiente de determinação ((R 2 =0.85). Na subsequente temporada esta relação foi utilizada para controlar a frequência de irrigação em duas variedades de uva de mesa. A quantidade de irrigação foi estabelecida para repor 10% de humidade aproveitável. O ensaio 1 foi realizado na variedade Thompson Seedless e baseou-se em dois tratamentos: T1, plantas...

Modeling Stem Water Potential by Separating the Effects of Soil Water Availability and Climatic Conditions on Water Status in Grapevine (Vitis vinifera L.)

“…The relation between SWP and PLWP in grapevine has been shown to follow a linear function under both irrigated (Williams and Araujo, 2002; Williams and Trout, 2005) and rainfed (Zufferey and Murisier, 2007) conditions. At the same time, SWP is known to decrease with increasing vapor maximum deficit (VPD), but this relationship has been demonstrated to change over the growing season (Olivo et al, 2009) and to be different among and within species (McCutchan and Shackel, 1992; De Swaef et al, 2009; Rogiers et al, 2009; Marchin et al, 2016), and irrigation treatments (Williams and Baeza, 2007; Gálvez et al, 2014).…”

Deficit irrigation in table grape: eco-physiological basis and potential use to save water and improve quality

“…Furthermore, Gálvez et al (2014) tested the implementation of deficit irrigation controlled on the basis of stem water potential and vapor pressure deficit (VPD) in the cvs 'Red globe' and 'Thompson Seedless'. Water use under DI was reduced in the cv.…”

“…70 %), or yet, to lower soil water availability as observed for the cv. 'Thompson Seedless' (Gálvez et al 2014).…”

“…For example, Allen et al (1998) established that soil water depletion greater than 30 % of the available soil water is a critical point for table grapes although it varies with soil type and atmospheric conditions (T air , VPD). Several parameters to assess vine's water status have been used in table grape production namely trunk diameter variation (TDV), berry growth, leaf/stem water potential and leaf temperature (Avidan et al 2005;Kopyt and Ton 2005;Gálvez et al 2014). The TDV allows an early and quantitative detection of vine's response to soil water availability during the vegetative and reproductive growth but the variation coefficients can be larger than the ones obtained for water potential (Silva-Contreras et al 2012).…”

Programación de riego y déficit hídrico controlado en frutales de hueso

“…Entre sus ventajas destacan su menor variabilidad, mejor correlación con el déficit de presión de vapor (DPV) y que refleja mejor la disminución de agua en el suelo que Ψh. Diversos trabajos han puesto de manifiesto la utilidad de este indicador en diversos frutales como albaricoquero (Pérez-Sarmiento et al, 2010); granado ; olivo (Moriana et al, 2012); uva de mesa (Gálvez et al, 2014) y melocotonero (Abrisqueta et al, 2015).…”