early maturity of grapevines in se australia between 1995 and 2009 was associated with early onset...

Early maturity of grapevines in SE Australia between 1995 and 2009 was associated with early onset rather than faster ripening

Victor Sadras and Paul Petrie

CCRSPI Conference, Melbourne 15-17 February 2011

Aim 1measure the effects of elevated temperature on vines and wines

temperature x variety

temperature x fruit load

temperature x water

Time (day of year)

0 20 40 60 800

10

20

30S

ug

ar c

on

cen

trat

ion

(%

)

Aim 2modelling grapevine maturity for harvest and post-harvest operations

Aim 2modelling grapevine maturity for harvest and post-harvest operations

Current approach - direct measurements - fixed rate 1 oBé per week

Sadras et al. (2008) Australian J Grape & Wine Research 14, 250

b

xx

e

SS

0

1

max

Cab Sauvignon, 1993-2006

Rate of change in time to 12 Be

Petrie & Sadras (2008) Australian J Grape & Wine Research 14: 33

Rate [d/yr]

1. Sadras VO, Petrie PR (2011). Quantifying the onset, rate and duration of sugar accumulation in berries from commercial vineyards in contrasting climates of Australia. Australian Journal of Grape and Wine Research in press.

2. Sadras VO, Petrie PR (2011). Climate shifts in south-eastern Australia: early maturity of Chardonnay, Shiraz, and Cabernet Sauvignon is associated with early onset rather than faster ripening. Australian Journal of Grape and Wine Research in press.

- Data from commercial vineyards

- Three vintages (2007 to 2009)

- Three regions:•Riverland, mean January temperature above 23 oC•Barossa Valley, 21.0 < mean January temperature < 22.9 oC •Coonawarra, 19.0 < mean January temperature < 20.9 oC

- Major varieties in each region

study 1

Thermal time (oC d)

Thermal time (oC d)

Thermal time (oC d)

90th percentile

Thermal time (oC d)

Cabernet Sauvignonn = 3148

0 300 600 900 12000

2

4

6

8

10

12

14

16

18

Merlotn = 451

Thermal time (oCd)

To

tal s

olu

ble

so

lids

(oB

é)

Shirazn = 1696

0 300 600 900 1200

Chardonnayn = 535

0

2

4

6

8

10

12

14

16

18Coonawarra

Coonawarrar = 0.90P < 0.0001

Vapour pressure (kPa)

1.1 1.2 1.3 1.4 1.5 1.6 1.7

Gap

(oB

é)

-1

0

1

2

3

4

ChardonnayMerlotCab SauvignonShiraz

- Data from commercial vineyards

- 15 vintages (1995 and 2009).

- Three regions:•Riverland, mean January temperature above 23 oC•Barossa Valley, 21.0 < mean January temperature < 22.9 oC •Coonawarra, 19.0 < mean January temperature < 20.9 o

-Cab Sauvignon, Shiraz, Chardonnay

-15 vintages x 3 climatic regions range of - average seasonal temperature 5 oC - VPDmax: 1.4 kPa

study 2

1998

2004

2010M

ean

tem

per

atu

re(o

C)

15

20

1998

2004

2010

1998

2004

2010

Coonawarra Barossa Riverland

Vintage

Rad

(M

J m

-2)

20

25E

vap

(m

m)

5

10

1998

2004

2010

VP

Dm

ax

(kP

a)

1

2

3

1998

2004

2010

1998

2004

2010

Vintage

Coonawarra Barossa Riverland

cool

0

4

8

12

16

hot

n = 793

0 40 80 1200

4

8

12

16

n = 1624

0 40 80 120To

tal s

olu

ble

so

lids

(oB

é)

0

4

8

12

16

n = 1134

n = 877

n = 3588

n = 3946

Coonawarra

n = 1505

0 40 80 120

n = 1587

0 40 80 120

n = 2682

n = 6052

Day of year

n = 1568

n = 9705

cool hot

Barossa

n = 4414

0 40 80 120

n = 1612

0 40 80 120

n = 1704

n = 5465 n = 5285

n = 4128

cool hot

Riverland

Ch

ardo

nn

ayS

hiraz

Cab

Sav

15 16 17 18 19 20 21Tim

e o

f 12

oB

é (d

ay o

f ye

ar)

0

20

40

60

80

100

r2 = 0.87P < 0.0001

Average temperature (oC)

-9.8 ± 0.94 days per oC

ChardonnayShirazCab Sauvignon

15 16 17 18 19 20 21

On

set

(day

of

year

)

-20

0

20

40

60

15 16 17 18 19 20 21R

ate

(oB

é d

-1)

0.00

0.05

0.10

0.15

0.20

0.25

ChardonnayShirazCab Sauvignon

Average temperature (oC)

r2 = 0.81P < 0.0001 P > 0.14

Onset (day of year)

-20 -10 0 10 20 30 40 50

Tim

e o

f 12

oB

é

(da

y o

f ye

ar)

0

20

40

60

80

100 ChardonnayShirazCab Sauvignon

r2 = 0.86P < 0.0001

Rate (oBé d-1)

0.08 0.12 0.16 0.200

20

40

60

80

100

r2 = 0.21P = 0.056

Growers, vineyard and weight bridge staff from Treasury Wine Estates Ltd. for collecting the maturity and yield data.

Harry Driscoll for help with the database.

Francisco Sadras and Mary Barnes for help with data analyses.

Grape and Wine Research and Development Corporation of Australia and the Department of Agriculture, Forestry and Fisheries for financial support.

Thanks

ConclusionsWarming is a complex syndrome including biologically relevant factors such as higher vapour pressure deficit with direct consequences for grapevine ripening.

Early ripening associated with the warming syndrome over recent decades has been primarily related to shifts in onset rather than increase in rate of ripening.

A simple onset-rate model can be coupled with (i) short-term temperature forecasts to predict the trajectory of sugaring for management purposes, and (ii) long-term records of temperature to produce probabilistic profiles of maturity date.