Coping Strategies for a Warmer Climate: Irrigation and Canopy Management Mike Trought Plant and Food Research Marlborough Research Centre Blenheim, New Zealand
Total producing area 2015 = 35,859 ha Auckland 398 Gisborne 1,914 Nelson 1,139 Hawkes Bay 4,773 Wairarapa 1,006 Marlborough 23,203 Waipara 1,451 Otago 1,951
MARLBOROUGH VINEYARD REGION NZ Vintage 2016: (436,000 T) (34,661T) (303,711T) (29162T) (323,290T)
Warming temperatures are a challenge and concern for many grape growers What are the possible long term changes and how might one deal with them in the vineyard? Being proactive Manipulating phenology Canopy management What are the short term effects of heat stress and how might one deal with them? Shading Effect of water stress
The long-term story
Seasonal changes in Sauvignon blanc flowering date simulated using Grapevine Flowering Véraison (GFV) model Simulated date of flowering 28 Dec 18 Dec 8 Dec 28 Nov Gisborne Hawke's Bay Marlborough Otago 18 Nov 1990 1995 2000 2005 2010 2015 Harvest year Trought, M. et al. (2016) Changing New Zealand climate equals a changing New Zealand terroir? Jones, G.V., and Doran, N., eds. 11th International Terroir Congress; McMinnville, Oregon, USA pp. 59-64.
Seasonal changes in véraison date of Sauvignon blanc simulated using the GFV model Predicted date of véraison 27 Feb 20 Feb 13 Feb 6 Feb 30 Jan 23Jan 16 Jan 1990 1995 2000 2005 2010 2015 Harvest year Gisborne Hawke's Bay Marlborough Otago
Seasonal changes in date of Sauvignon blanc 20 o Brix simulated using Parker maturity model 18 May 28 Apr Gisborne Hawke's Bay Marlborough Otago 20 o Brix date 29 Mar 19 Mar 27 Feb 7 Feb 1990 1995 2000 2005 2010 2015 Harvest year
Season changes in the mean daily temperature from véraison to harvest (8 to 20 o Brix) Average daily temperature 8 to 20 o Brix ( o C) 24 22 20 18 16 14 12 10 8 1990 1995 2000 2005 2010 2015 Harvest year Gisborne Hawke's Bay Marlborough Otago
So what can one do?
Variety So what can one do? Change varieties Pn (2450) Coping with an increase in temperature by selecting alternative grapevine varieties Predicting véraison date using the GFV model Looking towards the equator SB (2528) Sy (2601) CS (2689) While selection of alternative grapevine varieties may provide a means of mitigating climate warming, the reputation of many regions is based on specific varieties. Industries may be reluctant to make these changes Parker, A. et al. (2013) Classification of varieties for their timing of flowering and veraison using a modelling approach: A case study for the grapevine species Vitis vinifera L. Agricultural and Forest Meteorology 180, 249-264. Tannat (2840) 2000 2400 Véraison F* 2800
Influence of temperature changes on predicted Sauvignon blanc phenology Phenological dates predicted for Current (1987 to 2014) ( ) Current +0.5 o C ( )and Current +2.0 o C ( ) temperatures using the Grapevine Flowering Véraison model (Parker 2011, 2013, 2014). Trought, M.C.T. et al. (2014) Can a change in vineyard practice mitigate warming due to climate change? Acta Horticulturae 1082, 397-402. Proportion of seasons to reach flowering by a particular date (%) Proportion of seasons to reach veraison by a particular date (%) Proportion of seasons to reach 200g/L by a particular date (%) 100 80 60 40 20 0 5 Nov 15 Nov 25 Nov 5 Dec 15 Dec 25 Dec 100 80 60 40 20 0 14 Jan 3 Feb 23 Feb 15 Mar 100 80 60 40 20 (a) (b) (c) 0 The New 3 Zealand Feb Institute 23 Feb for Plant 15 & Food MarResearch 4 Apr Limited 24 Apr Date
Predicted Sauvignon blanc phenology with a +0.5 and +2.0oC temperature rise Phenological dates predicted for Current (1987 to 2014) ( ) Current +0.5 o C ( )and Current +2.0 o C ( ) temperatures using the Grapevine Flowering Véraison model (Parker 2011, 2013, 2014). Proportion of seasons to reach flowering by a particular date (%) Proportion of seasons to reach veraison by a particular date (%) Proportion of seasons to reach 200g/L by a particular date (%) 100 80 60 40 20 0 5 Nov 15 Nov 25 Nov 5 Dec 15 Dec 25 Dec 100 80 60 40 20 0 14 Jan 3 Feb 23 Feb 15 Mar 100 80 60 40 20 (a) (b) (c) 0 3 Feb 23 Feb 15 Mar 4 Apr 24 Apr Date
Predicted temperatures during ripening (8 to 20 o Brix) Proportion of seasons with a ripening temperature below a particular value (%) Percentage of seasons with ripening temperatures warmer than a particular value 0 100 20 80 40 60 60 40 80 20 100 0 12 14 16 18 20 22 24 Temperature during ripening ( o C) Current (1987 to 2014) ( ) Current +0.5 o C ( )and Current +2.0 o C ( ) temperatures
Percentage of seasons with ripening temperatures warmer than a particular value Predicted temperatures during ripening (8 to 20 o Brix) Proportion of seasons with a ripening temperature below a particular value (%) 0 100 20 80 40 60 60 40 80 20 100 0 12 14 16 18 20 22 24 Temperature during ripening ( o C) Current (1987 to 2014) ( ) Current +0.5 o C ( )and Current +2.0 o C ( ) temperatures
Percentage of seasons with ripening temperatures warmer than a particular value Effect of delaying véraison date by five days on mean temperature during ripening (8 to 20 o Brix) Proportion of seasons with a ripening temperature below a particular value (%) 0 100 2080 40 60 60 40 80 20 100 0 12 14 16 18 20 22 24 Temperature during ripening ( o C) Current (1987 to 2014) ( ) Current +0.5 o C ( )and Current +2.0 o C ( ) temperatures
DOY véraison Manipulating in the vineyard: Methods of delaying véraison 0 % crop removal 50 July Aug Early Sept Late Sept Time of pruning (Friend et al. 2007) Manipulating leaf area to fruit mass ratio (Parker et al. 2014) Control NAA application Application of NAA (Boettcher et al. 2012) 0 90 Days from spraying
Effect of leaf area: fruit weight ratio on sugar accumulation and acid decrease Vines trimmed to 6 or 12 leaves and 0, 50 or 75% fruit removed after fruit set Decreasing the leaf area: fruit weight ratio has a bigger effect on sugar accumulation than acid degradation Parker, A.K. et al. (2014) Leaf area to fruit mass ratio determines the time of veraison in Sauvignon blanc and Pinot noir grapevines. Australian Journal of Grape and Wine Research 20, 422-431. Parker, A.K.(2015) Manipulating the leaf area to fruit mass ratio alters the synchrony of total soluble solids accumulation and titratable acidity of grape berries. Australian Journal of Grape and Wine Research 21, 266-276.
Effect of leaf area: fruit weight ratio on sugar accumulation and acid decrease Vines trimmed to 6 or 12 leaves and 0, 50 or 75% fruit removed after fruit set Decreasing the leaf area: fruit weight ratio has a bigger effect on sugar accumulation than acid degradation Data from Amber Parker 2013
Thinning at fruit set, modelling 8 Brix (Veraison) Pinot noir and Sauvignon blanc DOY of year corresponding to 8 Brix Inadequate leaf area is delaying ONSET 65 60 Pinot noir Sauvignon blanc 55 Response is a continuum 50 45 Leaf area : fruit weight ratio is not limiting 40 0.5 1.0 1.5 2.0 2.5 LA:FW (m 2 /kg) Parker, A.K. (2012) Modelling phenology and maturation of the grapevine Vitis vinifera L.: Varietal differences and the role of leaf area to fruit weight ratio manipulations. PhD thesis, Lincoln University, Lincoln University, New Zealand.
Average daily soluble solids accumulation, (8 to 21 o Brix) Pinot noir and Sauvignon blanc Leaf &/or yield limiting: 0.7 0.6-6 leaves -12 leaves + 100% crop Soluble solids/ Day 0.5 0.4 0.3 0.2 Leaf area : fruit weight ratio is not limiting on rate 0.1 0.0 Pinot noir Sauvignon blanc 0.0 0.5 1.0 1.5 2.0 2.5 LA/FW (m 2 /kg) Amber Parker
Fruit acidity normalised against soluble solids Titratable acidity (g/l) 45 40 35 30 25 20 15 Sauvignon blanc 2009-10 6 leaves 100% crop 6 leaves 50% crop removal 6 leaves 75% crop removal 12 leaves 100% crop 12 leaves 50% crop removal 12 leaves 75% crop removal 10 4 6 8 10 12 14 16 18 20 22 24 Soluble solids
Influence of trimming and thinning at véraison on acid:soluble solids ratio of Sauvignon blanc fruit. Acid sugar ratio affects the texture of wine The timing and degree of trimming will influence the ratio Tall full crop; Tall part crop; Trimmed full crop; Trimmed part crop. Delanoue G, Trought M et al. Unpublished data
Influence of trimming and thinning at véraison on fruit nitrogen:soluble solids ratio of Sauvignon blanc fruit. Fruit nitrogen concentrations are important in determining particular aroma compounds (e.g. 3-mercaptohexanol contributing to grapefruit, passionfruit tropical aromas) The timing and degree of trimming will influence the ratio Tall full crop; Tall part crop; Trimmed full crop; Trimmed part crop
Short-term options
Effect of temperature on leaf photosynthesis: Light saturated maximum rates of photosynthesis of Semillon leaves Light saturated (Greer maximum and Weedon rates 2011) of photosynthesis of Semillon leaves (Greer and Weedon 2011) Net photosynthesis (umol m -2 s -1 ) 30 25 20 15 10 5 0 15 20 25 30 35 40 45 Leaf temperature ( o C)
Changes in Semillon Changes net in photosynthesis Semillon net photosynthesis before and after after exposure to a 40/25oC regime for 4 exposure days (Greer to a 40/25oC and Weston regime 2010) for 4 days (Greer and Weston 2010) 6 Net photosynthesis (umol m -2 s -1 ) 5 4 3 2 1 0 Heat Treatment -2 0 2 4 6 8 10 12 14 16 Days from start of heat treatment flowering mid-ripening
Cumulative minutes east-exposed Malbec leaf surface temperature exceeding 30 o Cumulative minutes east-exposed Malbec leaf surface C, irrigated and non-irrigated, Idaho. (Shellie and King 2013) temperature exceeding 30 o C, irrigated and non-irrigated, Parma, Idaho (Shellie and King 2013) East-exposed leaf surface temperature >30 o C (cumulative minutes) 8000 6000 4000 2000 0 Standard irrigation Reduced irrigation 1 Aug 21 Aug 10 Sept Date
Influence of Malbec cluster exposure and irrigation on cumulative Influence of Malbec cluster exposure and irrigation on minutes berry surface temperature exceeded 30 o C. (Shellie and King 2013) cumulative minutes berry surface temperature exceeded 30 o C (Shellie and King 2013) Berry surface >30 o C (cumulative min) 14000 12000 10000 8000 6000 4000 2000 East standard irrigation East reduced irrigation 0 31 Jul 20 Aug 19 Sept Date
Influence of Malbec cluster exposure and irrigation on cumulative minutes berry surface temperature exceeded 30 o C. (Shellie and King 2013) Influence of Malbec cluster exposure and irrigation on cumulative minutes berry surface temperature exceeded 30 o C (Shellie and King 2013) Berry surface >30 o C (cumulative min) 14000 12000 10000 8000 6000 4000 2000 East standard irrigation East reduced irrigation West standard irrigation West reduced irrigation 0 31 Jul 20 Aug 19 Sept Date
What factors can influence water availability in the vineyard?
What factors can influence water availability in the vineyard? Crop Root length (cm / cm 2 soil surface area) Grapevines 0.9 4.0 Apples 0.8 24.0 Cereals 100-4000 Grapevines are poor competitors for water and nutrients with herbaceous plants. Weed competition will result in poor nutrition and stress
Using chicory and ryegrass to de-vigorate Sauvignon blanc (Trought and Naylor)
Influence of inter-row chicory and ryegrass on soil moisture and shoot development of Sauvignon blanc grapevines (Trought and Naylor) Effect of soil management on soil-water content Effect of understory on soil water content Effect of soil management on shoot growth of Sauvignon blanc grapevines Effect of understory Sauvignon blanc Shoot growth 0.30 100 Soil moisture (m 3 m -3 ) 0.25 0.20 0.15 Bare ground Ryegrass Chicory Shoot length (cm) 80 60 40 20 Bare ground Ryegrass Chicory 0.10 N D J F M A Date 0 N D J F M A Date
Influence of sub-surface irrigation on weed growth of young vines Photographs courtesy of Mark Allen
Subsurface irrigation
Depth (cm) Just one final thought Roots are not uniformly distributed in the soil profile 0 120 240 10 20 30 Percent soil moisture
Nitrogen and potassium accumulation by grape berries (Ollat and Gaudillere 1996)
Changes in soil potassium concentration and root density in soils of the Wairau Plain Potassium concentration (nm) Root (cm cm 2 ) Root density (cm cm 2 0.16 0.14 0.12 0.10 0.08 0.06 0.04 0.02 XS vine M vine XL vine 0.00 0 20 40 60 80 100 120 140 160 180 Profile depth (cm) Profile depth (cm) XS M XL XS vine M vine Phtotgraphs courtesy of Tim Mills XL vine Mills, T. (2006) Relations among geology, soil type and Sauvignon blanc vineyard variation in Marlborough, New Zealand. The University of Auckland, The University of Auckland. Potassium concentration (mm) 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0.0 0 20 40 60 80 100 120 140 160 180 Profile depth (cm) Profile depth (cm)
Influence of seasonal rainfall on must potassium and nitrogen concentrations 600 400 Rainfall (mm) Must potassium (g L -1 ) 1.00 120 Rainfall (mm) 500 400 300 200 100 rainfall must K Brancardoro et al 1994 0.95 0.90 0.85 Must potassium (g/l) Juice nitrogen nutrition (mg/l) 300 200 100 Optimum Yeast Assimilable Nitrogen conc. (21 o Brix) 100 80 60 40 20 Rainfall mm (Jan 1 - Feb 28) 0 1987 1988 1989 1990 Year 0.80 0 2006 2007 2008 2009 2010 yan prim aa NH4 rainfall Year 0
Summary: Seasons appear to be getting warmer, although the effect is not necessarily uniform at all sites. The earlier date of véraison with increased temperatures results is a warmer ripening period This is a legacy we will be leaving to our grandchildren
Summary We can delay the date of véraison and slow sugar accumulation by reducing the leaf area: fruit weight ratio. But this desynchronises the metabolites in the berries, changing sugar: acid and sugar: nitrogen (and probably other metabolites)
Summary Irrigation and minimising water stress will reduce heat stress of the leaves and fruit And minimising competition between grapes and herbaceous plants will maximise water availability Cumulative minutes east-exposed Malbec leaf surface temperature exceeding 30 o C, irrigated and non-irrigated, Parma, Idaho (Shellie and King 2013) East-exposed leaf surface temperature >30 o C (cumulative minutes) 8000 6000 4000 2000 0 Standard irrigation Reduced irrigation 1 Aug 21 Aug 10 Sept Date Soil moisture (m 3 m -3 ) 0.30 0.25 0.20 0.15 Effect of soil management on soil-water content Bare ground Ryegrass Chicory 0.10 N D J F M A Date
Summary Maintaining good nutrition is important as drought may result in increased unavailability of nutrients, in particular potassium, particularly during ripening 600 1.00 500 rainfall must K 0.95 Rainfall (mm) 400 300 200 Brancardoro et al 1994 0.90 0.85 Must potassium (g/l) 100 0 1987 1988 1989 1990 0.80 Year
Acknowledgments: Oregon Winegrowers for the invitation to visit Oregon once again. My many colleagues and friends that I have collaborated with in my research programmes over many years. In particular: Rob Agnew, Amber Parker, Paul Petrie, Andrew Naylor, Andy Sturman, Kees van Leeuwen, And the team at the Marlborough Research Centre Much of my work is part of the Plant and Food Research Grape and Wine Research programme, funded by the MBIE Strategic Science Investment Fund (SSIF), delivered by PFR in consultation with New Zealand Winegrowers.
I look forward to seeing you at the Marlborough Wine and Food Festival in 2018 Thank you www.plantandfood.co.nz mike.trought@plantandfood.co.nz