4
ARTICLES
RIA / Vol. 38 / N.º 1
Influence of temperature on the
composition of Vitis vinifera L. cv Pinot
Noir bunches, exposed to the east and
west and in different stages of maturity
GALLINA, M.1
ABSTRACT
Grape berry composition (weight, sugars, acids, polyphenols) is influenced by factor such as the canopy
microclimate and different maturity stages. The scope of the current research was to determine the influence
of temperature on grape berry composition (weight, volume, soluble solids, total acidity, pH, anthocyanins and
Total Polyphenols Index - TPI) in two different exposures (ease and west) and three different maturity stages.
Results show that bunches exposed to the west presented higher temperature accumulation and were exposed longer to temperatures exceeding the maximum physiological threshold than those exposed to the east.
Weight and volume records of grapes exposed to the west were lower than values recorded in grapes exposed
to the east, but only in advanced maturity stages. No differences were found in regards with soluble solids,
total acidity, pH, anthocyanins and TPI in grapes exposed to east and west or at different maturity stages.
Keywords: temperature accumulation, microclimate, radiation, anthocyanins, acidity, TPI, exposure.
INTRODUCTION
In vineyards with row orientation north-south, bunches
exposed in the west or east sides of canopy have different
microclimates that lead to different grape features and composition. This is attributed to higher or lower temperature
and radiation incidence (Deloire and Hunter, 2005). The
optimum temperature for anthocyanins’ synthesis is 25 to
30° C during the day (Gonzáles Neves, 2005). But the accumulation of anthocyanins could be affected by the lack
of synthesis or degradation in berries exposed to temperatures above 30 to 35° C, (Spayd et al., 2002; Gonzáles
Neves, 2005).
Grapes berries exposed to high temperature and radiation levels were smaller (Bergqvist et al., 2001; Deloire and
1
Hunter, 2005), presented higher levels of soluble solids and
lower titratable acidity (Bergqvist et al., 2001; Tomasi et al.,
2003). They also displayed higher anthocyanins content
(Smart et al., 1988; Tomasi et al., 2003), higher phenols
content in the skin (Price et al., 1995) and higher pH (Bergqvist et al., 2001; Deloire and Hunter, 2005).
Other authors did not find differences in grape weight
(Haselgrove et al., 2000), soluble solids (Haselgrove et al.,
2000; Tomasi et al., 2003), pH (Price et al, 1995; Tomasi et
al., 2003) or anthocyanins concentration (Price et al, 1995)
when comparing bunches exposed to light with those maintained in the shade.
These results differ from those obtained in investigations
that found lower anthocyanins and total phenols content in
INTA, EEA Alto Valle, CC 782, (8332) General Roca, Río Negro. Correo electrónico: mgallina@correo.inta.gov.ar
Received April 29th 2011 // Accepted November 17th 2011 // Published online January 25th 2012
Influence of temperature on the composition of Vitis vinifera L. cv Pinot Noir bunches, exposed to the east and west (...)
April 2012, Argentina
5
the skin of grapes that were excessively exposed to radiation (Haselgrove et al., 2000; Bergqvist et al., 2001), and
also found lower soluble solids content in bunched exposed
to sunlight (Deloire and Hunter, 2005).
and two inner berries from the same areas. Therefore, 64
grape berries from each experimental unit were collected.
It was then hypothesized that cv Pinot Noir grapes under
west orientation (in north-to-south rows) may have different
analytical composition than grapes oriented to the east,
such as less polyphenols concentration, smaller size and
higher pH. These changes would be associated with adaptation to higher temperatures.
Three samplings were taken from each plot, totalizing
192 grapes. Samples were preserved in a container with
ice for transportation to the laboratory. Each group of 192
grapes was sorted according to diameter (Ojeda, 1999) and
grapes of the modal class were used to determine anthocyanins, TPI, weight and volume. The remaining samples
from modal class were homogenized, as well as the grapes from other diameter categories, to assess soluble solids using an Atago refractometer (Atago Co., Ltd., Tokyo,
Japan), pH (using a 80 mL aliquot of a Bicasa pH meter
-Italy- with temperature correction and calibrated to pH 4.0
using a buffer solution) and total acidity.
The scope of the present investigation was to determine the influence of temperature on weight, volume, soluble
solids, pH, acidity, anthocyanin concentration and Total Polyphenols Index (TPI) in grape clusters of Pinot Noir with
east or west orientation and at three maturity stages.
Total acidity was determined as follows: a 10 mL aliquot
was obtained and diluted to 20 mL with distilled water. Afterwards, 5 drops of bromothymol blue were added and the
obtained solution was titrated using NaOH 0.1 N until the
solution shifted to greenish-blue.
Moreover, different stages of maturity at harvest may
be associated with differences in grapes composition and
yields (McCarthy and Coombe, 1999; Hunter et al., 2004).
MATERIALS AND METHODS
A seven-year old ungrafted Vitis vinifera L. vineyard was
used, cv. Pinot Noir. The vineyard was located at EEA INTA
Alto Valle, province of Río Negro, Argentina (39º 01’ S;
67º 40’ W3; 240 m.a.s.l.). Rows were oriented north-south,
with an inclination of 7-8° northeast-southwest. Rows were
separated by 2.5 m., and plants were separated 1.2 m. A
counter espalier system4 was used, with 1.9 m. final height.
Pruning system was bilateral cordon at height 0.8 m.
The experimental design was a factorial arrangement of
6 treatments, 3 times of harvest (early, middle and late) x 2
exposures (east and west), randomized complete block. Evaluations were made in two consecutive seasons with 4 replications in 2005-2006 and 7 repetitions in 2006-2007. The
following treatments were considered: T1: early harvest, east
exposure; T2: early harvest, west exposure; T3: middle harvest, east exposure; T4: middle harvest, west exposure; T5:
late harvest, east exposure; T6: late harvest, west exposure.
Plots considered the direction of irrigation. The experimental unit comprised three paired rows. Within each row,
an area between two clearings in between adjacent poles
– with six plants each – was considered. Thus, each experimental unit included 36 plants. Grape bunches exposure
was established by considering the plane defined by the
poles and wires of the counter espalier as division criterion.
Maturity was defined as “middle” (approximately 24° Brix)
at harvest. “Early” and “late” were defined as two weeks
before and after, respectively.
Sample grapes were taken between 9 AM and 11 AM
to avoid weight variation occurring during the day (Coombe and Bishop, 1980). 192 grapes were taken as sample
for each repetition, at each harvest time and exposure
(Roessler, et al., 1958; Roessler, et al., 1963). Four grape
bunches were randomly collected from two clearings in between poles at each experimental unit. Four grape berries
were severed with scissors at the pedicel as follow: an outer
berry from the top area, an outer berry from the lower area
Anthocyanins and TPI were analyzed according to the
method described by Riou and Asselin (1996). Weight was
assessed with an analytical balance (model Handy, Sartorius), and volume was determined measuring the volume of
water displaced in 50 mL and 250 mL graduated cylinders.
Temperature of grape bunches was determined using termographs TDL 2048, (San Carlos de Bariloche, province
of Río Negro) and LOGGER8 (Cavadevices, province of
Buenos Aires). In 2005-2006 a sensor taking records every
15 minutes was used, whereas in 2006-2007 three sensors
were used to obtain values every 5 minutes. In 2005-2006
temperature was recorded from 87 DAA (days after anthesis) (February 9th, 2006) to 96 DAA (February 18th, 2006)
and from 108 DAA (March 2nd, 2006) to 117 DAA (March
11th, 2006). In 2006-2007 temperature was recorded from
72 DAA (January 25th, 2007) to 81 DAA (February 3rd, 2007).
For each exposure (east/west), the number of hours/
day above a certain temperature threshold was recorded
in 2005-2006 from 87 DAA (February 9th, 2006) to 96 DAA
(February 18th, 2006); and from 107 DAA (March 1st, 2006)
to 116 DAA (March 10th, 2006). In 2006-2007 temperatures
were recorded from 72 DAA (January 25th, 2007) to 81 DAA
(February 3rd, 2007).
Heat summation was obtained by adding all temperature
records exceeding the 10° C, 20° C, 30° C, 35° C and 40°
C thresholds. Hours/day exceeding the thermal threshold
were calculated by considering the number of records exceeding that threshold and multiplied by the time between
records. In 2005-2006 data from 87 DAA (February 9th,
2006) to 96 DAA (February 18th, 2006) and from 107 DAA
(March 1st, 2006) to 116 DAA (March 10th, 2006) was used.
Records from 71 DAA (January 24th, 2007) to 112 DAA
(March 6th, 2007) were used in 2006-2007.
RESULTS AND DISCUSSION
Temperature of grape bunches according to exposure
Average daily and minimum temperatures showed no differences between east and west exposures. However, average
GALLINA, M.1
ARTICLES
6
RIA / Vol. 38 / N.º 1
daily maximum temperatures were always higher for grapes
with western exposure, in both seasons (Figures 1 and 2).
Maximum temperatures often exceeded the 30º C - 35º
C range (Figures 3 and 4), critical for the physiological performance of the plant (Haselgrove et al., 2000; Gonzáles
Neves, 2005).
solids content when comparing grapes under different exposures and at each harvest date. But unlike Reynolds et
al.(1986) and Spayd et al. (2002), no differences in pH of
the wort were observed when compared different exposures at different harvest dates. Reynolds et al.(1986) and
Spayd et al. (2002) found that pH was higher in grapes under western exposure.
Temperature accumulation records with bases 10° C, 20°
C, 30° C, 35° C and 40° C were always higher in grapes
under western exposure, with the exception of records of
the 10° C group in 2006-2007, which presented the inverse
trend (Figures 5 and 6). This is consistent with the work of
Spayd et al. (2002).
No differences in titratable acidity were observed in wort
from grapes under east or west exposure, at different harvest dates. In Canada, Reynolds et al. (1986) also found no
differences in acidity at harvest between the two exposures. But Spayd et al. (2002) in Prosser (Washington, United
States) found that grapes exposed to the west displayed
lower acidity, as a consequence of higher temperatures.
Fresh weight, volume and composition of grape berries
No differences in the content of anthocyanins (per kg or
per grape berry) were observed between exposures at any
harvest date, in both seasons. As grapes exposed to the
west suffer higher temperatures, above the critical threshold, and as the daily duration of critical temperatures is
more important than temperature records (Spayd et al.,
2002), it can be suspected that grape berries under west
exposure would show a reduction in polyphenols synthesis
or would suffer some type of degradation.
Weight and volume of grape berries under western exposure was lower in the third harvest date in both seasons
(tables 1 and 2). This may be attributed to dehydration from
perspiration and lack of water supply to the fruit, consequence of the interruption of the phloem flow in this period
(Coombe and Mc Carthy, 2000), although at that stage there would not be higher physiologic sensibility to high temperatures, resulting from exposure to radiation (Hale and
Buttrose, 1974; Spayd et al., 2002).
Coinciding with Reynolds et al. (1986) and Spayd et al.
(2002) no differences were found in regards with soluble
East exposure
Hours/day number
40
ºC
East exposure
West exposure
50
30
20
10
0
Mean
temperature
Maximum
temperature
Minimum
temperature
Figure 1. Temperature at cluster level in the east and the west
exposures, 2005-2006 season.
40
30
20
10
0
Mean
temperature
Maximum
temperature
Minimum
temperature
Figure 2. Temperature at cluster level in the east and the west
exposures, 2006-2007 season. Average of three data loggers with
lower and higher limits of confidence intervals (95%).
25
20
15
10
5
0
>10ºC
>30ºC
>35ºC
>40ºC
Figure 3. Number of hours/day exceeding a temperature threshold
for each exposure, 2005-2006.
East exposure
West exposure
50
West exposure
Base temperature
Hours/day number
East exposure
ºC
A possible hypothesis would be that only berries of from
the area of the bunch receiving direct sunlight undergo these processes, and that these grape berries would dilute in
the batch of berries from the same bunch, as not all of them
West exposure
25
20
15
10
5
0
>10ºC
>30ºC
>35ºC
>40ºC
Base temperature
Figure 4. Number of hours/day exceeding a temperature threshold
for each exposure, 2006-2007. Average values ​​from three sensors,
including lower and upper confidence intervals limits (95%).
Influence of temperature on the composition of Vitis vinifera L. cv Pinot Noir bunches, exposed to the east and west (...)
April 2012, Argentina
7
East exposure
West exposure
GDD
21.792 22.544
8.671 9.071
1.411
>10ºC
>20ºC
2.217
140 719
>30ºC
7
>35ºC
81
>40ºC
Base temperature
Figure 5. Temperature accumulation records with bases 10º C, 20º C, 30º C, 35º C and 40° C for each exposure, 2005-2006.
East exposure
West exposure
GDD
118.503 116.950
1.664
>10ºC
>20ºC
4314
>30ºC
58
908
>35ºC
0
74
>40ºC
Base temperature
Figure 6. Temperature accumulation records with bases 10º C, 20º C, 30º C, 35º C and 40° C for each exposure, 2006-2007.
experience the same temperature increase. Tomasi et al.
(2003) reports a temperature difference of 8° C or more in
grape berries from the same bunch, both directly exposed
to sunlight or not.
These results contrast with those reported by Spayd et
al., (2002) where anthocyanins content at harvest are significantly lower when exposed to the west.
No differences were recorded in TPI among different exposures, with the exception of 119 DAA in 2005-2006.
No interaction between harvest dates (early, middle and
late) and exposure of the grapes (east and west) for any of
the assessed variables was observed during the two seasons. This would mean that the grapes achieved on each
harvest date a certain maturity stage regardless their orientation, following an additive process.
CONCLUSSIONS
There are differences in microclimate thermal conditions
when bunches are exposed either to the east or the west.
Bunches exposed to the west display higher maximum temperatures, temperature accumulation and longer periods of
critical temperatures.
However, the postulated hypothesis was not validated because although grapes under west exposure and late harvest
were smaller, due to dehydration, no differences in soluble solids, pH, total acidity, anthocyanins or TPI were observed in
grapes under different exposures and at each maturity stage.
No interactions were observed between exposure and
maturity, and therefore it is not possible to postulate that
grapes under eastern or western exposure reach optimum
maturity at different times.
GALLINA, M.1
8
ARTICLES
RIA / Vol. 38 / N.º 1
Berry component
Berry mass Berry volume
(g/berry)
(cc/berry)
Soluble
solid
(ºbrix)
pH
TA
Anthocyanins Anthocyanins
(g tartaric
(mg/ berry)
(mg/kg berry)
acid/L)
IPT
Early harvest,
east exposure
1,478a
1,326a
21,58
(21,04-22,12)
3,39a
7,76
(7,55-7,97)
393,54a
0,658a
32,84a
Early harvest,
west exposure
1,435a
1,359a
22,01
(21,13-22,88)
3,48a
7,33
(6,87-7,79)
381,85a
0,638a
32,43a
p value
0,29
0,34
*
0,1
0,0534
0,0531
0,163
1,457a
1,308a
25,06
(24,59-25,53)
3,41a
6,9 (6,9-6,9)
409,95a
0,685a
31,78a
1,425a
1,339a
25,04
(24,95-25,12)
3,44a
6,65
(6,26-7,05)
391,72a
0,639a
30,67b
0,17
0,15
*
0,31
0,0685
0,1
0,0483
28,27a
3,57a
7,01
(6,94-7,08)
447,46a
0,640a
36,15a
1,233b
28,65a
3,62a
6,75
(6,21-7,29)
428,94a
0,614a
35,35a
0,029
0,23
0,21
0,18
0,19
0,374
Normal
harvest, east
exposure
Normal
harvest, west
exposure
p value
Late harvest,
east exposure 1,275a
Late harvest,
west exposure
p value
*
*
*
Harvest date x
exposure
NS
NS
NS
NS
NS
NS
p value
0,94
0,45
0,94
0,29
0,15
0,79
Table 1. Grape composition under eastern and western exposure, in a espalier and at each maturity stage, 2005-2006. On each data
pair, of each harvest date, different letters indicate significant differences (p ≤ 0.05); (*) indicates non-compliance with some assumption
of ANOVA; parentheses indicate confidence intervals (95%).
Berry component
Berry mass Berry volume
(g/berry)
(cc/berry)
Soluble
solid
(ºbrix)
pH
TA
Anthocyanins Anthocyanins
(g tartaric
(mg/kg berry)
(mg/ berry)
acid/L)
IPT
Early harvest,
east exposure
1,476a
1,336a
22,40a
3,38a
8,70a
438,54a
0,603a
26,27a
Early harvest,
west exposure
1,373a
1,246a
23,14a
3,39a
8,77a
432,92a
0,595a
25,67a
p value
0,0773
0,0804
0,0654
0,66
0,76
0,16
0,17
0,102
1,501a
1,380a
23,20
(22,27-24,13)
3,45a
8,28a
432,12a
0,596a
26,04a
1,463a
1,340a
23,70
(23,47-23,93)
3,46a
7,96a
423,43a
0,581a
25,82a
0,42
0,37
*
0,58
0,0743
0,19
0,0769
0,56
Late harvest,
east exposure
1,461a
1,336a
24,21a
3,55a
7,55a
429,18a
0,614a
27,25a
Late harvest,
west exposure
1,370b
1,235b
24,35a
3,57a
7,29a
421,02a
0,603a
26,41a
0,022
0,028
0,69
0,7
0,26
0,19
0,21
0,19
Harvest date x
exposure
NS
NS
NS
NS
NS
NS
NS
NS
p value
0,44
0,26
0,17
0,85
0,18
0,91
0,74
0,63
Normal
harvest, east
exposure
Normal
harvest, west
exposure
p value
p value
Table 2. Grape composition under eastern and western exposure, in a espalier and at each maturity stage, 2006-2007. On each data
pair, of each harvest date, different letters indicate significant differences (p ≤ 0.05); (*) indicates non-compliance with some assumption
of ANOVA; parentheses indicate confidence intervals (95%).
Influence of temperature on the composition of Vitis vinifera L. cv Pinot Noir bunches, exposed to the east and west (...)
April 2012, Argentina
9
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the fenolic composition of Vitis vinifera cv. Shiraz grape berries.
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Viticultural Zoning, 15-19 november 2004, Cape Town, South Africa. 466-478
MCCARTHY, M.G.; COOMBE, B.G. (1999) Is weight loss in ripening grape berries cv. Shiraz caused by impeded phloem transport.
Australian Journal of Grape & Wine Research. 5: 17-21
OJEDA, H. (1999) Influence de la contrainte hidrique sur la
croissance de péricarpe et sur l’évolution des phénols des baies
de raisin (Vitis vinifera L.) cv. Syrah. Tesis doctoral de la Escuela
Nacional Superior Agronómica de Montpellier, 159 p.
PRICE, S.F., BREEN, P.J.; VALLADAO, M.; WATSON, B.T.
(1995) Cluster sun exposure and quercetin in Pinot noir grapes
and wine. Am. J. Enol. Vitic. 46(2): 187-194
REYNOLDS, A.G.; POOL, R.M.; MATTICK, L.R. (1986) Influence of cluster exposure on fruit composition and wine quality of Seyval blanc grapes. Vitis 25: 85 – 95
RIOU, V.; ASSELIN, C. (1996) Potentiel polyphénolique disponible du raisin: Estimation rapide par extraction partielle à chaud.
Progrès Agricole et Viticole. 113(18): 382-384
ROESSLER, E.B.; AMERINE, M.A. (1958) Studies on grape
sampling. Am. J. Enol. Vitic., 9 : 139-145
ROESSLER, E.B.; AMERINE, M.A. (1963) Further studies on
field sampling of wine grapes. Am. J. Enol. Vitic., 14 : 144-147
SMART, R.; SMITH, S.M. ; WINCHESTER, R.V. (1988) Light
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SPAYD, S.E.; TARARA, J.M.; MEE,D.L.; FERGUSON, J.C. (2002)
Separation of sunlight and temperature effects on the composition
of Vitis vinifera cv. Merlot berries. Am. J. Enol. Vitic. 53:3, 171-182
TOMASI, D.; PITACCO, A.; PASCARELLA, G. (2003) Bunch
and berry temperature and anthocyanin synthesis and profile in
Cabernet sauvignon. Riv. Vitic. Enol.4: 3-15
HALE, C.R.; BUTTROSE, M.S. (1974) Effect of temperature on
ontogeny of berries of Vitis viniferaL. Cv: Caberrnet sauvignon. J.
Amer. Soc. Hort. Sci. 99(5):390-394
HASELGROVE, L. BOTTING, D., VAN HEESWIJCK, R., HØJ,
P. B., DRY, P. R., FORD, C., ILAND, P.G.. (2000) Canopy microclimate and berry composition: The effect of bunch exposure on
the fenolic composition of Vitis vinifera cv. Shiraz grape berries.
Australian Journal of Grape and Wine Research 6: 141-149
HUNTER, J.; PISCIOTTA, A.; VOLSCHENK, C.; ARCHER, E.;
NOVELLO, V.; KRAEVA, E.; DELOIRE. A.; NADAL, M. (2004) Role
of harvesting time / optimal ripeness in zone / terroir espression.
Proc. Joint OIV, GESCO, SASEV. Intl. Conference on Viticultural
Zoning, 15-19 november 2004, Cape Town, South Africa. 466-478
MCCARTHY, M.G.; COOMBE, B.G. (1999) Is weight loss in ripening grape berries cv. Shiraz caused by impeded phloem transport.
Australian Journal of Grape & Wine Research. 5: 17-21
OJEDA, H. (1999) Influence de la contrainte hidrique sur la
croissance de péricarpe et sur l’évolution des phénols des baies
de raisin (Vitis vinifera L.) cv. Syrah. Tesis doctoral de la Escuela
Nacional Superior Agronómica de Montpellier, 159 p.
PRICE, S.F., BREEN, P.J.; VALLADAO, M.; WATSON, B.T.
(1995) Cluster sun exposure and quercetin in Pinot noir grapes
and wine. Am. J. Enol. Vitic. 46(2): 187-194
REYNOLDS, A.G.; POOL, R.M.; MATTICK, L.R. (1986) Influence of cluster exposure on fruit composition and wine quality of Seyval blanc grapes. Vitis 25: 85 – 95
RIOU, V.; ASSELIN, C. (1996) Potentiel polyphénolique disponible du raisin: Estimation rapide par extraction partielle à chaud.
Progrès Agricole et Viticole. 113(18): 382-384
ROESSLER, E.B.; AMERINE, M.A. (1958) Studies on grape
sampling. Am. J. Enol. Vitic., 9 : 139-145
ROESSLER, E.B.; AMERINE, M.A. (1963) Further studies on
field sampling of wine grapes. Am. J. Enol. Vitic., 14 : 144-147
SMART, R.; SMITH, S.M. ; WINCHESTER, R.V. (1988) Light
quality and quantity effects on fruit ripening for Cabernet Sauvignon. Am. J. Enol. Vitic. 39:3, 250-258
SPAYD, S.E.; TARARA, J.M.; MEE,D.L.; FERGUSON, J.C. (2002)
Separation of sunlight and temperature effects on the composition
of Vitis vinifera cv. Merlot berries. Am. J. Enol. Vitic. 53:3, 171-182
TOMASI, D.; PITACCO, A.; PASCARELLA, G. (2003) Bunch
and berry temperature and anthocyanin synthesis and profile in
Cabernet sauvignon. Riv. Vitic. Enol.4: 3-15
GALLINA, M.1