Leaf area, light environment, and gas exchange in Montepulciano grapevines trained to Tendone trellising system

This article was downloaded by: [Univ Studi Basilicata]On: 05 July 2012, At: 03:17Publisher: Taylor & FrancisInforma Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House,37-41 Mortimer Street, London W1T 3JH, UK

Plant Biosystems - An International Journal Dealingwith all Aspects of Plant Biology: Official Journal of theSocieta Botanica ItalianaPublication details, including instructions for authors and subscription information:http://www.tandfonline.com/loi/tplb20

Leaf area, light environment, and gas exchange inMontepulciano grapevines trained to Tendone trellisingsystemP. Giorio a & V. Nuzzo ba Consiglio Nazionale delle Ricerche – Istituto per i Sistemi Agricoli e Forestali delMediterraneo (CNR-I.S.A.FO.M.), via Patacca, 85, 80056 - Ercolano, Naples, Italyb Dipartimento di Scienze dei Sistemi Colturali, Forestali e dell'Ambiente, Università degliStudi della Basilicata, Viale dell'Ateneo Lucano, 10, 85100, Potenza, Italy

Version of record first published: 04 Jul 2011

To cite this article: P. Giorio & V. Nuzzo (2012): Leaf area, light environment, and gas exchange in Montepulciano grapevinestrained to Tendone trellising system, Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology:Official Journal of the Societa Botanica Italiana, 146:2, 322-333

To link to this article: http://dx.doi.org/10.1080/11263504.2011.557095

PLEASE SCROLL DOWN FOR ARTICLE

Full terms and conditions of use: http://www.tandfonline.com/page/terms-and-conditions

This article may be used for research, teaching, and private study purposes. Any substantial or systematicreproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form toanyone is expressly forbidden.

The publisher does not give any warranty express or implied or make any representation that the contentswill be complete or accurate or up to date. The accuracy of any instructions, formulae, and drug doses shouldbe independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims,proceedings, demand, or costs or damages whatsoever or howsoever caused arising directly or indirectly inconnection with or arising out of the use of this material.

Leaf area, light environment, and gas exchange in Montepulcianograpevines trained to Tendone trellising system

P. GIORIO1 & V. NUZZO2

1Consiglio Nazionale delle Ricerche – Istituto per i Sistemi Agricoli e Forestali del Mediterraneo (CNR-I.S.A.FO.M.), via

Patacca, 85, 80056 - Ercolano, Naples, Italy and 2Dipartimento di Scienze dei Sistemi Colturali, Forestali e dell’Ambiente,

Universita degli Studi della Basilicata, Viale dell’Ateneo Lucano, 10, 85100 - Potenza, Italy

AbstractCanopy light interception (CPFDInt), spectral irradiance, leaf water potential, gas- exchange and optical properties weremeasured in an irrigated vineyard (Vitis vinifera L. cv Montepulciano) trained to the so-called tendone system in which leafarea index (LAI) was varied by means of 50% (T50) or 75% (T75) cluster removal. The 20.5 t ha71 yield in the unthinnedtreatment (UT) decreased by only 36% in T50 and by 52% in T75. LAI and CPFDInt similarly increased until summerpruning when LAI was 1.75 m2 m72 in UT, and 25.6% or 62.2% higher in T50 and T75, respectively. The two thinnedtreatments had only 12.4% higher CPFDInt than in UT (1167.1 mmol m72 s71) due to the increased leaf self-shading. Thered-to-far red ratio (R: FR) was as low as 0.10 below the canopy. Light-saturated CO2 assimilation (Amax) in June averaged14.4 mmol m72 s71 in sun-exposed leaves, and 7.6 mmol m72 s71 in shade leaves. By contrast, the apparent quantum yieldof CO2 assimilation (fe) was not significantly affected by leaf position, averaging 0.029 and 0.070 mol mol71 in June andOctober, respectively. Middle and low canopy leaves had only 27 or 6%, respectively, of the top canopy leaves actual CO2

assimilation rate.

Keywords: Radiation capture, leaf photosynthesis, stomatal conductance, A/Q curve, spectral irradiance

Abbreviations: A, net CO2 assimilation rate; CPFDInt, canopy light interception; F, spectral irradiance; gs,stomatal conductance to water vapor; LAI, leaf area index; PFD, photosynthetically active photon flux density; LCP,light compensation point; Rd, dark respiration; R:FR, red-to-far red ratio; cl, leaf water potential; fe, apparentquantum yield of CO2 assimilation; a, absorptance; t, transmittance; r, reflectance

Introduction

Vine dry matter accumulation is largely driven by

canopy photosynthesis, which is strongly determined

by leaf area and its capacity to intercept and use solar

radiation (Kliewer & Dokoozlian 2005). Since the

early 1960s, a threshold for annual crops has been

reported beyond which leaf area index (LAI, m2

m72) is no longer linked to dry matter production

because of the mutual shading among leaves in the

canopy profile. Since then, solar radiation inter-

cepted by the canopy has been used as a robust

estimation of crop dry mass production (Monteith

1994). In contrast to light interception, LAI above a

certain threshold results in a large over-estimation of

the actual canopy source potential in vineyards, as in

annual crops. The increase in vineyard light inter-

ception is strictly correlated with LAI during the

early shoot-growing season, while later this relation-

ship persists in conventional pruning (CP) systems,

but is disrupted in minimal pruning systems as leaves

undergo mutual self-shading (Intrieri et al. 2001). In

fact, training and trellising systems strongly affect

vineyard canopy–light interaction (Smart 1973,

1985; Dokoozlian & Kliewer 1995).

Shade canopy experiments have shown eco-phy-

siological adaptation of grapevine leaves to the

radiation regime. The light response of leaf photo-

synthesis (A/Q curve) in simple cordon grapevines

grown under shaded environments showed increased

apparent quantum yield of CO2 assimilation (fe, mol

mol71) and decreased light-saturated CO2

Correspondence: P. Giorio, Consiglio Nazionale delle Ricerche Istituto per i Sistemi Agricoli e Forestali del Mediterraneo (CNR-I.S.A.FO.M.), via Patacca,

85, 80056 - Ercolano, Naples, Italy. Email: [email protected]

Plant Biosystems, Vol. 146, No. 2, June 2012, pp. 322–333

ISSN 1126-3504 print/ISSN 1724-5575 online ª 2012 Societa Botanica Italiana

http://dx.doi.org/10.1080/11263504.2011.557095

Dow

nloa

ded

by [

Uni

v St

udi B

asili

cata

] at

03:

17 0

5 Ju

ly 2

012

assimilation (Amax, mmol m72 s71), dark respiration

(Rd, mmol m72 s71), light compensation point

(LCP, mmol m72 s71), and saturating photosyn-

thetic photon flux density (PFD, mmol m72 s71)

compared to vines grown under full light (Palliotti

et al. 2000). As a consequence, most canopy

photosynthesis is due to direct light absorbed by

the exterior canopy leaves (Smart 1974). Thus, the

trade-off between light interception and the photo-

synthetic light response within the different canopy

leaf layers determines the overall conversion effi-

ciency of solar energy into chemical energy, namely

the vine potential productivity.

The Italian tendone (large tent) is an overhead

horizontal undivided canopy trellising system quite

common in southern Italy for both wine- and table-

grape production (de Palma & Novello 2004; Rana

et al. 2004). This system was developed, around the

end of the 19th century, from the capanna (hut)

system, a pergola type system used in central Italy

(Fanelli 1965). These systems were designed to reduce

the number of vines per hectare in order to allow for

soil mechanization, avoid physical contact of table

grape berries with leaves, shoots and tendrils, protect

clusters from sunburn, heavy showers and hail, and

protect canes from freezing or snow (Fanelli 1965).

Tendone canopies achieve a full surface ground cover

(Smart 1985). Under these conditions, all the incom-

ing light hits the canopy surface while virtually no

direct light can reach the ground. In rectangular

canopies, this feature can only be approximated by

minimizing the distance between vines (Smart 1973).

On the other hand, the leaf area directly exposed to

solar radiation is minimized in horizontal canopies as

compared with other trellising systems, which is the

opposite of what is required to increase light energy

available for photosynthesis so as to enhance yield

(Smart 1973, 1974, 1985). Not surprisingly, vineyards

with moderate shoot vigour resulting in open canopies

were given the best ratings in the 80-point scoring-

system evaluation of vineyard balance (leaf area- to-

yield ratio) and potential fruit quality (Smart &

Robinson 1991; Kliewer & Dokoozlian 2005). As

regards direct solar radiation, in the tendone system

there is no mutual shading between leaves in different

outer-surface canopy zones during the daytime, but

only a continuous lower leaf layer shading by upper

layers. Compared with the top surface leaves, the lower

shoot leaves in tendone canopies actually experience,

during most of their mature life, a shaded environ-

ment, which can be described by both the spectrum of

radiation and the red- to-far red (R: FR) ratio

(Dokoozlian & Kliewer 1995). Summer pruning is a

standard operation adopted in tendone canopies. Such

a technique reduces leaf shading to facilitate ventilation

in the fruit zone (de Palma & Novello 2004), controls

excessive cluster shading, and avoids contact of table

grapes with other organs. Cluster- and leaf-shading in

wine grape vineyards clearly may have negative effects

on yield, berry composition, and wine quality (Smart

1985; Morrison & Noble 1990). However, a shaded

environment in the fruit-zone, when not excessive, can

have positive effects on table grape ripening since it

prevents irregular berry skin pigmentation and sun-

burn (de Palma & Novello 2004).

Grapevines trained to tendone are considered

capable of good yields (Fanelli 1965; de Palma &

Novello 2004). However, despite the relevant eco-

nomic importance of such vineyards in southern Italy

(Rana et al. 2004), there is little or no literature on

canopy light interception (CPFDInt), light response

of leaf photosynthesis, and the effect of leaf position

within tendone vineyards.

In a red wine grape (cv Montepulciano) commer-

cial vineyard trained to tendone in southern Italy, LAI

evolution was varied by means of early cluster

thinning, which also affected the yield. We studied

CPFDInt in relation to LAI, light quality along the

canopy profile, and the photosynthetic light response

(A/Q curve), and optical properties in both sun-

exposed and shade leaves.

Materials and methods

Vineyard information and experimental design

The trial was carried out in 2002 in a drip-irrigated

6-year old Vitis vinifera L. cv Montepulciano vine-

yard with plants grafted on V. berlandieri Planch. x V.

rupestris Scheele (1103 P). The experimental site was

in the Metaponto (MT) plain of southern Italy (N

408 200, E 168 480, elevation 50 m asl). The soil was a

clay-loam, classified as a ‘‘typic haploxealf fine

loamy, mixed, semiactive, thermic’’ with depths of

2 m or more. The vineyard had rows oriented SE to

NW (2208 390) with vines spaced 2.5 m6 2.5 m,

giving a plant density of 1600 vines per hectare. The

vines with two arms, and two canes per arm, were

pruned to 10 buds per cane, and trained to the

tendone system, forming a complete overhead canopy

with free-standing shoots. The vine trunks were tied

to vertical tutors used to support a horizontal wire

grid, thus allowing shoots to spread above all over the

ground surface at a height of 1.8–2.2 m where most

of the leaf area was found.

Three cluster thinning treatments were established

in 2001 and repeated in 2002 immediately after fruit

set as follows: the unthinned (UT) control having

about two clusters per shoot, and two thinned

treatments having one cluster per shoot (T50) or

one cluster per two shoots (T75). The three thinning

treatments were imposed in a randomized complete

block design. There were three replicates for each

treatment in two adjacent rows (15 vines/row)

Light environment and gas exchange in Tendone grapevines 323

Dow

nloa

ded

by [

Uni

v St

udi B

asili

cata

] at

03:

17 0

5 Ju

ly 2

012

with five vines per replicate. On 6 July 2002 (berry

pea-sized), the vineyard was subjected to a standard

summer pruning operation by the partial removal of

most shade-leaves, unproductive shoots, and the

vigorous basal lateral shoots. In the previous year, the

same vines had been subjected to the same cluster

thinning and summer pruning.

Meteorological data were obtained from a station

of the ‘‘Agenzia Lucana per lo Sviluppo ed Innova-

zione in Agricoltura’’ located 15 km away. We chose

an irrigated vineyard, and monitored leaf water

potential to make our results comparable with other

experiments.

Yield and leaf area estimation

Clusters were harvested when the average soluble

solids of the vineyards were about 208 Brix as

determined by the ordinary criteria of the Metaponto

plain, and were counted and weighed on a vine-by-

vine basis. Soluble solids were determined from berry

juice by using a hand-held model MT032ATC

refractometer (TCW Equipment, Saint Helena, CA).

Canopy leaf area evolution was estimated by

combining destructive and non-destructive methods.

We discriminated between main and laterals shoot

stems as they are differently affected by cluster

thinning, though such an effect is not investigated in

this article. At flowering, the total stem length (TSLf)

of both main and lateral stems of all shoots were

separately measured in vivo in each of nine vines per

treatment. From May to harvesting time, 6 to 8

shoots per treatment were collected, stored at about

38C in suitable protective bags, and quickly brought

to the laboratory to measure main and lateral stem

lengths (SL), and one-sided surface area of all leaves

on each stem (LA) by means of a Li-3100 photo-

metric area-integrating meter (LiCor, Lincoln, NE,

USA). A linear regression analysis was applied to the

relationship between LA and SL, which gave an R2

higher than 0.8. In addition, 6 to 8 more shoots per

treatment were selected and tagged to increase the

shoot number used to assess the ratio between stem

length at flowering (SLf) and during the season (SLi).

TSL in each vine during the season (TSLi) was

calculated as TSLi¼TSLf6SLi/SLf. Plant leaf area

(PLA) during the season was calculated as

PLA¼ ai6TSLi þ bi (where ai and bi are the

parameters of the linear regression as above), for

both main and lateral stems, which were summed

and then converted to LAI on the basis of the

vineyard plant density.

Light interception

Measurements of the PFD (expressed as mmol m72

s71, and taken from 400 to 700 nm) were carried out

around noon on cloudless days from May to Septem-

ber by using a linear Accupar 80 ceptometer (Decagon

Device Inc., Pullman, WA, USA). The ceptometer

had 80 sensors spaced at 1-cm intervals, and was

programmed to average readings of every 10 sensors

before logging data. The PFD transmitted through the

canopy (PFDT) was measured at 0.25 m above the

soil surface over a grid of 0.16 0.2 m2 across the area

allocated to three vines to obtain four replicates of the

incident light-intercepting canopy surface unit of 0–

1.25 m across, and 0–2.50 m along the row from the

vine trunk. Measurements were completed within

15 min for each treatment. The canopy transmitted

light, CPFDT, was obtained as the average of PFDT

over the grid points. The incident PFD (PFDI) was

calculated as the mean of 10 PFD measurements taken

above the canopy during PFDT measurements.

Intercepted PFD (PFDInt) for each point on the grid

was calculated as PFDI7PFDT. Diffused and re-

flected components were not considered. The canopy

intercepted light, CPFDInt, was obtained as the

average of PFDInt over the grid points, whereas the

fractional light interception, fi, was calculated as

CPFDInt/PFDI.

Light quality

The spectral distribution of solar radiation was

measured with a Li-1800 spectro-radiometer (Li-

Cor, Lincoln, NE, USA) equipped with the cosine

corrected sensor. The spectrum from 330 to 1100

nm was scanned every 2 nm wavelength. Data

measured were expressed as spectral irradiance (F,

W m72 nm71) or quanta flux density (Q, mmol m72

s71). The spectrum data were used to calculate the

R: FR ratio of quanta wavebands (654–666 nm, and

724–736 nm, respectively). Measurements were

taken on two sunny days after summer pruning on

five vertical positions: over the top canopy (2.2 m

height), two heights within the foliage (2.0 and

1.8 m), and two heights below the foliage (1.6 and

1.4 m) at 0.5 m from the vine along the row line. At

harvest, on shade- and sun-exposed mature non-

senescent leaves, spectral parameters were measured

from 400 to 900 nm, scanned each 2 nm, using the

same spectro-radiometer as above equipped with an

integrating sphere.

Leaf gas exchange and water potential

The light response of leaf net photosynthesis (A/Q

curve) was assessed by measuring steady state CO2

assimilation (A, mmol m72 s71) at 16 points in the

PFD range from 2000 to 0 mmol m72 s71 using a

portable Li-6400 photosynthesis system (Li-Cor,

Lincoln, NE, USA) equipped with a leaf chamber

36 2 cm2 wide. Light was provided by an artificial

324 P. Giorio and V. Nuzzo

Dow

nloa

ded

by [

Uni

v St

udi B

asili

cata

] at

03:

17 0

5 Ju

ly 2

012

red LED source emitting at 670 nm. An external

bottled 12 g CO2 source was used to infiltrate the

leaf chamber with air at a constant 370 mmol mol71

CO2. The various gas-exchange parameters were

calculated by the instrument software on the basis of

the von Caemmerer and Farquhar (1981) model.

Using the software Photosyn Assistant (Dundee

Scientific, Dundee, Scotland), A/Q curve data were

fitted to a non-rectangular hyperbola model func-

tion, in which the apparent quantum yield of CO2

assimilation (fe, mol mol71) was the initial curve

slope, the light-saturated assimilation (Amax) was the

upper asymptote, and the light compensation point

(LCP, mmol m72 s71) and the dark respiration

(Rd, mmol m72 s71) were the axis intercepts.

Mature shade-leaves near a cluster in the low canopy

and well-exposed mature leaves at the canopy top were

selected for measurements in three vines per treat-

ment. The A/Q curves were carried out between 10:00

and 14:30 h solar time as each curve took about

30 min to be completed. After A/Q curve determina-

tion, the leaves were cut and enclosed in a bag filled

with breath air to avoid any significant loss of vapor,

and then leaf water potential (cl, MPa) was immedi-

ately measured by means of a Scholander pressure

bomb (PMS Instruments, Corvallis, OR, USA).

Statistical analysis

Data were submitted to analysis of variance using

SigmaStat 3.0.1 software (SSPS, Inc., Chicago, IL,

USA). When warranted, the Student Newman–

Keuls test was used to compare the means. The

relationship between leaf area and shoot length was

established by regression analysis.

3. Results

Meteorological patterns and leaf water status

Meteorological patterns showed the typical Mediter-

ranean climate of southern Italy. The daily minimum

and maximum temperature in July were 20.3 and

32.28C, respectively, and both were the highest

values compared with other months. The average

daily reference evapo-transpiration estimated with

the Hargreaves equation was highest in June

(6.3 mm day71) and slightly lower in July and

August (data not shown).

Analysis of variance showed that Cl was signifi-

cantly affected by the leaf position factor while

neither the cluster thinning factor nor the first-order

interaction between the two factors were significant.

Mean comparisons were, therefore, performed be-

tween the two leaf positions within single sampling

dates. Cl was significantly lower in sun than shade-

leaves, both remaining quite stable with an overall

average value of 71.07 MPa in the sun-exposed

leaves and 70.87 MPa in the shade-leaves (Table I).

Yield, leaf area index and light interception

The cluster thinning treatment applied at fruit set

resulted in T50 and T75 vines having respectively

58% and 37% of 63.7 (control) clusters per vine at

harvesting time (Table II). The reduced cluster load

significantly affected yield, which decreased from

20.5 t ha71 (control) to 74% (T50) and 48% (T75).

The soluble solids in the berry juice were 2.6 kg per

vine (control), a halved content in the most thinned

T75 treatment, and a moderate reduction in T50, in

accordance with the yield reduction (Table II).

LAI increased during the growing season (Figure

1a) with the maximum value observed in early July

when it was 1.75 m2 m72 in UT, and 25.6% (T50)

and 62.2% (T75) higher. Any further increase in leaf

area was prevented by the ordinary summer pruning

that removed most of shade-leaves near the fruit zone

as well as some vigorous lateral shoots and unpro-

ductive shoots. This operation was quite strong and

uniform as it halved the leaf area in all treatments

(Figure 1a), a typical feature for commercial tendone

vineyards in the Metapontum plain. After pruning,

shoot growth allowed only a partial recovery of LAI

before a clear decrease due to late season leaf

senescence (Figure 1a).

As observed for leaf area, light interception

increased during the growing season. The maximum

radiation interception occurred in early July just

before summer pruning, when CPFDInt was

1167.1 mmol m72 s71 in UT and on average

12.4% (not statistically significant) higher in the

two thinned treatments (Figure 1b). After pruning,

there was a partial recovery followed by a decrease, as

found for leaf area.

Light quality

As expected, the tendone vineyard showed a lower

transmittance in the photosynthetically active wave-

Table I. Leaf water potential (Cl, MPa) of sun-exposed and shade-

leaves measured around midday from June to October 2002 as an

average of the three thinning treatments.

Month Sun-leaf Shade-leaf

June 71.11+0.031 a 70.84+ 0.027 b

July 70.85+0.058 a 7068+ 0.017 a

August 71.00+0.031 a 70.82+ 0.054 b

September 71.19+0.026 a 71.01+ 0.021 b

October 71.21+0.022 a 70.99+ 0.022 b

Note: The data are presented as mean+SEM (n¼15). Means in

the same row with the same letter are not significantly different

(SNK test; p� 0.05).

Light environment and gas exchange in Tendone grapevines 325

Dow

nloa

ded

by [

Uni

v St

udi B

asili

cata

] at

03:

17 0

5 Ju

ly 2

012

band radiation (400–700 nm) as compared with the

near infrared waveband radiation (700–1100 nm)

(Figure 2). One week after summer-pruning (Figure

2a), the irradiance at 2 m wire height (a few leaf

layers below the top canopy surface) was 6.7% (400–

700 nm) and 36.5% (700–1100 nm) of the incoming

radiation above the canopy on average for all

thinning treatments, whereas a month later it was

3.4% and 40.9% for the two wavebands, respectively

(Figure 2b).

The R: FR ratio, which is inversely related to

canopy shadiness, was strongly reduced by the

canopy leafiness. On average for all thinning treat-

ments, the R: FR ratio decreased in mid-July (1 week

after summer pruning) from 1.12 measured above

canopy to 0.29 at 2 m height within the canopy

foliage. R: FR further decreased to 0.10 below the

canopy foliage, with comparable values observed a

month later (Figure 3a). With regards to the optical

Table II. Clusters per vine (n vine71), cluster weight (g cluster71), grape yield (t ha71), and berry juice soluble solids as content (kg vine71)

or concentration (degrees Brix) measured at harvesting time for the three thinning treatments, UT, T50 and T75.

Category

Treatment

UT T50 T75

Clusters per vine 63.67+ 2.10 a 36.79+1.38 b 23.70+ 0.99 c

Cluster weight 204.17+ 5.48 a 257.92+9.13 b 260.80+ 9.13 b

Grape yield 20.55+ 0.58 a 15.14+0.74 b 9.81+ 0.47 c

Soluble solids content 2.56+ 0.09 a 2.06+0.10 a 1.34+ 0.07 b

Soluble solids concentration 19.85+ 0.27 a 21.86+0.40 a 21.91+ 0.36 b

Note: The data are presented as mean+SEM (n¼ 30).

Means in the same row with the same letter are not significantly different (SNK test; p�0.05).

Figure 1. LAI (a; m2 m72) and CPFDInt, (b; mmol m72 s71) in

the UT (closed circle), T50 (open triangle), and T75 (open

square) cluster thinning treatments during one growing season.

One-way ANOVA was performed for each sampling date. The

data are presented as means+SEM (LAI: n¼9; CPFDInt: n¼ 4).

Means in the same row with the same letter are not significantly

different (SNK test; p� 0.05). Upper, middle, and bottom letters

refer to T75, T50, and UT treatments, respectively. For the sake

of clearness, letters are not shown when means were not

significantly different. Upward and downward arrows indicate

cluster thinning and summer pruning date, respectively.

Figure 2. Spectral irradiance (F, W m72 nm71) as an average of

the three thinning treatments at 2.2 m (outer canopy surface), at

2.0 and 1.8, (within foliage), and at 1.6 and 1.4 m (below foliage)

in the 330- to 1100-nm waveband, measured at midday on 14 July

(a) and 8 September 2002 (b). The data are presented as

means+SEM (n¼ 3). For the sake of clearness, SEM is shown

every 40 nm.

326 P. Giorio and V. Nuzzo

Dow

nloa

ded

by [

Uni

v St

udi B

asili

cata

] at

03:

17 0

5 Ju

ly 2

012

properties measured in the control thinning treat-

ment, reflectance (r, a.u.) of the adaxial surface in

the two leaf positions were perfectly superimposed,

while only a slight difference was observed in the

transmittance (t, a.u.) and, therefore, the absorp-

tance (a, a.u.) above 730 nm. At higher wavelengths,

t was significantly higher, and therefore a lower, in

shade- than in sun leaves (Figure 3b). From these

data, we calculated an absorptance in the 400–700

nm waveband of 0.91 for both leaf positions.

Leaf gas exchange

Similarly to Cl, analysis of variance showed that gas-

exchange parameters were significantly affected by

the leaf position factor, while neither the cluster

thinning factor nor the first-order interaction be-

tween the two factors were significant. Mean

comparisons were, therefore, performed between

the two leaf positions within single sampling dates.

There was a strong effect of leaf position on some

parameters of the A/Q curve. Sun-exposed leaves had

significantly higher light-saturated CO2 assimilation

and stomatal conductance than shade leaves

(Table III). In June, Amax was 14.4 (sun-leaves)

and 7.6 (shade leaves) mmol m72 s71. The effect of

leaf position on stomatal conductance was slightly

stronger than on Amax. The average gs during the

season was 0.173 (sun leaves) and 0.078 (shade-

leaves) mol m72 s71. Although the apparent

quantum efficiency of CO2 in June was about 20%

higher in sun leaves, such a difference was not

statistically significant. In both leaf positions, fe

gradually increased during the season, with an

overall mean of 0.029 (June) and 0.070 (October)

mol mol71. As expected, both light compensation

point and dark respiration were higher in sun- than

in shade-leaves. During the season, LCP decreased

from 46.0 to 20.2 mmol m72 s71 in sun leaves, and

from 33.1 to 10.7 mmol m72 s71 in shade leaves.

The average Rd was 1.3 (sun leaves) and 0.8 (shade-

leaves) mmol m72 s71 (Table III).

Discussion

The physiological responses of V. vinifera to water

deficit can be characterized by either an anisohydric

or an isohydric behavior depending on the cultivar

(Beis & Patakas 2010) or irrigation regime (Giorio

et al. 2007). In our case, despite the stressful

environmental conditions occurring during the

summer, irrigation ensured quite a stable leaf water

potential (Table I). A table grape tendone vineyard in

the Apulia Region in southern Italy also had a good

Figure 3. (a) Average R: FR ratios of the three thinning treatments

in the canopy profile on 14 July and 8 September 2002 (mean-

s+SEM; n¼ 3), and (b) optical parameters in the 400- to 900-nm

waveband in sun- and shade leaves of the UT treatment (means+SEM; n¼ 6), with transmittance (t) and reflectance (r) plotted

as lines, and the absorptance (a) shown as the complement to 1 of

tþ r. For the sake of clearness, SEM is shown every 20 nm.

Table III. Light saturated leaf CO2 assimilation (Amax, mmol m72

s71), stomatal conductance to water vapor (gs, mol m72 s71),

apparent quantum efficiency for CO2 (fe, mol mol71), light

compensation point (LCP, mmol m72 s71), and dark respiration

(Rd, mmol m72 s71) obtained from the A/Q curves in sun-exposed

and shade leaves during the season as an average of the three

thinning treatments.

Month Parameter Sun leaves Shade leaves

Amax 14.4+ 2.1 a 7.6+ 0.6 b

gs 0.157+ 0.047 a 0.055+ 0.004 b

June fe 0.032+ 0.005 a 0.025+ 0.001 a

LCP 46.0+ 6.1 a 33.1+ 2.6 b

Rd 1.3+ 0.1 a 0.9+ 0.1 b

Amax 13.2+ 1.0 a 6.9+ 0.9 b

gs 0.168+ 0.022 a 0.067+ 0.012 b

September fe 0.059+ 0.004 a 0.061+ 0.03 a

LCP 22.8+ 2.5 a 12.8+ 1.5 b

Rd 1.3+ 0.2 a 0.8+ 0.1 b

Amax 11.3+ 1.0 a 8.2+ 0.9 b

gs 0.193+ 0.027 a 0.101+ 0.018 b

October fe 0.064+ 0.006 a 0.076+ 0.011 a

LCP 20.2+ 1.9 a 10.7+ 0.6 b

Rd 1.3+ 0.2 a 0.7+ 0.1 b

Note: The data are presented as mean+SEM (n¼ 9).

Means in the same row with the same letter are not significantly

different (SNK test; p�0.05).

Light environment and gas exchange in Tendone grapevines 327

Dow

nloa

ded

by [

Uni

v St

udi B

asili

cata

] at

03:

17 0

5 Ju

ly 2

012

aptitude to maintain an optimal water status even

when soil water content was quite low (Rana et al.

2004).

The negative effect of cluster thinning on yield was

associated with a significant increase in the cluster

weight at harvest (Table II), a well-known partial

self-compensation effect of cluster growth (Naor

et al. 2002). Our control treatment yielding 20.5 t

ha71 of grapes indicated a relatively high productiv-

ity for the Montepulciano tendone vineyard compared

to the 17.5 t ha71 yield reported for Cabernet

Sauvignon trained to a double cordon system with 48

buds per vine that is quite similar to our experiment

(Chapman et al. 2004).

Cluster thinning can stimulate leaf growth due to

the altered source–sink relationship (Edson et al.

1995). Thompson seedless grapevines showed a 50%

increase in the dry weight of leaves grown after

cluster removal at anthesis compared to the un-

thinned control (Williams 1996). Similarly, LAI of

the most thinned tendone was 62% significantly

higher than the control. The same vines in our

tendone were submitted to cluster thinning in the

previous year. This could explain the evident

increased LAI in the thinned treatments even at the

time of cluster removal (Figure 1a) due to a possible

beneficial effect of the improved accumulation of the

carbohydrate reserves in the trunk and roots during

the previous year.

The evolution of vineyard leaf area during the

season was reflected by a parallel increase in the light

intercepted by the canopy until the summer pruning

(Figure 1). Leaf area sampling can result in a linear

LAI during the growing season, as it was for the VSP

vineyard reported by Weyand and Schultz (2006).

However, with our data sets restricted to the time

before summer pruning, the statistical comparison of

the regressions of LAI or CPFDInt vs DOY (day of

year) (R24 0.99 or R24 0.95, respectively) indi-

cated a unique curve for all three thinning treatments

for LAI (p5 0.0001) but not for CPFDint

(p5 0.1502) (data not shown). Just before summer

pruning when the canopy achieved maximum

vegetative growth (Figure 1), the light intercepted

by the cluster-thinned canopies was, in fact, only a

little higher (12.4%) than the control. Conversely,

LAI was significantly [25.6% (T50) and 62.2%

(T75)] higher than the 1.75 m2 m72 found in the

control. These results clearly indicate that early-

cluster thinning in tendone systems affected LAI with

no significant effects on light interception. LAI was,

therefore, a canopy size parameter that hardly

described the potential productivity of the tendone,

as already found for other trellising systems (Glad-

stone & Dokoozlian 2003).

The geometry of tendone implies the absence of any

shading of the exterior (sun) leaves during the

daytime, and with a LAI above or even quite below

one, a significant portion of the canopy consists of

shaded interior leaves. The ratio between PLA and

canopy sun-exposed surface area (SA) represents a

shade index within the canopy, with self-shading

certainly occurring when such a ratio is higher than

one (Smart 1985). This shade index equals the LAI

in horizontal canopies, which therefore should be

maintained at relatively low LAI as compared to

other training systems in order to achieve minimal

shading. By comparing 10 training systems, Smart

(1985) not surprisingly found that a tendone vineyard

was among those having the highest shade index

(PLA/SA), despite having the same or halved LAI

(equal to PLA/SA in this system), as compared with

the other training systems.

The leaf area per unit of canopy volume, the leaf

area density (LAD, m2 m73), in the tendone control

(UT) was about 4.4 m2 m73, with the calculation

restricted to the 1.8–2.2 m vertical layer in which

most leaves were localized. Such a high LAD

occurring over all the ground surface also accounts

for the fact that a further increase of up to 5.5 (T50)

or 7.1 (T75) m2 m73 was not accompanied by a

substantial increase in light interception because of

leaf self-shading.

In addition, we observed more vertical lateral

shoots in the most thinned vines compared to the

control. These shoots accounted for a further leaf

area increase not associated with a corresponding

linear increase in CPFDInt. A parallel increase in

light interception and leaf area until the achievement

of the maximum PLA (19 m2 per m of row, in a

single row experiment) was observed by Intrieri et al.

(2001) in a Sangiovese vineyard trained to a CP

system. Such a LAI was capable of achieving a

fractional light interception of 78% during the

daytime. Our results can be compared with data of

Intrieri et al. (2001), since light interception mea-

surements taken at midday do not substantially

underestimate daytime measurements (Charles-Ed-

wards and Lawn 1984; Sinclair and Muchow 1999).

From data in Figure 1b, we calculated a 75%

(unthinned) and 84% (thinned treatments) fi just

before summer pruning.

From the same data, we obtained the relative

frequency distributions of PFDInt classes in our

tendone that showed a seasonal pattern that was quite

different from the one reported by Weyand and

Schultz (2006) for conventional and minimal prun-

ing Sylvoz systems. In those canopies, low PFDInt

classes had larger proportions early in the season,

and decreased during the season in favor of inter-

mediate classes of light interception. In our case, we

observed such a decrease for the low classes early in

the season, but it was first followed by an increase in

the upper PFD classes occurring from end of May to

328 P. Giorio and V. Nuzzo

Dow

nloa

ded

by [

Uni

v St

udi B

asili

cata

] at

03:

17 0

5 Ju

ly 2

012

early July, before the peak of relative frequency

shifted toward the mid-classes in August (Figure 4).

This indicated that a certain number of clustered leaf

layers developed locally before further growth

allowed the free-standing shoots to spread out over

the remaining uncovered ground. The spatial and

temporal variations of PFDInt until the end of May

actually confirmed that ‘‘oil spot’’ thick zones

developed in the canopy preceding full ground

covering (Figure 5). Therefore, a significant leaf

self-shading occurred in the tendone canopy, starting

quite early in the season. Summer pruning caused an

abrupt halving of LAI, although we could not analyze

the resulting effect on light interception as the

subsequent measurements were carried out in

August when the canopy had already recovered to

full closure (cf. Figures 1 and 6). However, a high

shadiness within the tendone foliage was also clearly

indicated by the strong reduction in spectral irra-

diance at 2 m height, just below the canopy top, even

a week after summer pruning (Figure 2a).

In vertically divided TK2T systems (Smart 1988),

the R: FR ratio below canopy decreased to about 0.2

when shoot density increased from 5 to 20 shoots

m71, while such a (reciprocal) shade index remained

at about 0.1 in canopies trained up to 70 shoots m71,

indicating a clear saturating effect on shadiness at

moderate canopy shoot density. Our data similarly

indicate that few leaf layers in a tendone canopy were

sufficient to absorb most of PFD and to impose a

high shade on the lowest leaf layers (Figures 2 and

3a). Light interception and its distribution, and

therefore the shadiness along the vertical canopy

profile, is actually due to the canopy architecture, the

leaf area density, and the optical leaf properties. We

found an absorptance in the PFD waveband as high

as 0.91 in all mature non senescing leaves, slightly

higher than the upper limit of 0.85 to 0.90 reported

in grapevines by Schultz (1996). Tendone canopy has

an intrinsically low sun-exposed surface in compar-

ison with other trellising systems (Smart 1985), and

our data clearly indicate that it was subjected to a

strong self-shading during most of the season.

Gas exchange parameters were not affected by the

cluster level under our experimental conditions. It is

well known that shade and sun-exposed leaves show

different photosynthetic responses to light and that

Amax is lower in shade leaves than sun-exposed leaves

Figure 4. Relative frequency distribution of classes of light interception (PFDInt, mmol m72 s71) measured over a grid of 0.16 0.2 m2 over

the ground below the UT (closed circle), T50 (open triangle), and T75 (open square) canopies throughout the season.

Light environment and gas exchange in Tendone grapevines 329

Dow

nloa

ded

by [

Uni

v St

udi B

asili

cata

] at

03:

17 0

5 Ju

ly 2

012

even at high saturating PFD (Hunter & Visser 1989;

Howell 2001). The assimilation rates and the

apparent quantum yield we found in sun leaves

(Table III) are similar to data reported elsewhere for

irrigated grapevines (e.g. de Souza et al. 2003; Baeza

et al. 2005). Amax in Sangiovese grapevines grown

under 30% sunlight was 59.5% of control vines

(Cartechini & Palliotti 1995), an effect that is quite

comparable with our data. All the A/Q curve

parameters reported by these authors indicated a

clear adaptation of grapevine leaves to the increasing

light. They found a fe value of 0.062 mol mol71 in

the 30% sunlight treatment, and one as low as 0.038

mol mol71 under full sunlight. We did not find such

a shading effect on fe due to leaf position, but only

five data points were taken in the linear region of the

A/Q curve (PFD5100 mmol m72 s71). Therefore,

caution is due in the interpretation of the difference

we found in fe (DeLucia et al. 1991). However, no

effect of increasing light intensity on fe is a common

feature for many species (Boardman 1977), and

plant architecture may override the detectable

differences in A/Q parameters if they are expressed

on a leaf area basis (Givnish 1988). By contrast,

Amax, LCP and Rd, as expected, were significantly

lower in shade leaves than sun leaves (Table III).

Silvestroni et al. (1993) reported no shading effect on

Amax for leaves that had expanded under full

sunlight, whereas there was a great reduction in

leaves that had been shaded during growth. There-

fore, despite the unaffected fe, leaves in the low-

canopy tendone were adapted to low light encoun-

tered during the season as they showed a strong

decrease in Amax. These leaves were under full

sunlight when they were young as well as during part

of their mature life, before shading by the developing

upper shoots or laterals took place.

For sun leaves, we can assume that around

midday the actual assimilation (A) was close to

Amax since they mostly received saturating light. For

Figure 5. Spatial variation of the light interception (PFDInt, mmol m72 s71) measured over a grid of 0.160.2 m2 over the ground below the

UT, T50, and T75 canopies from mid-May to mid-June 2002.

330 P. Giorio and V. Nuzzo

Dow

nloa

ded

by [

Uni

v St

udi B

asili

cata

] at

03:

17 0

5 Ju

ly 2

012

shade leaves, we did not measure A at the actual

PFD experienced within the canopy. In order to

estimate the contribution of shade leaves to canopy

photosynthesis as compared with the sun leaves,

we modelled the actual assimilation in relation to

PFD on the basis of the A/Q parameters, and the

canopy profile PFD measured in mid-September.

Shade leaves in the middle of the canopy foliage

(2.0 m height) at a PDF of 106 mmol m72 s71

assimilated CO2 at a rate of 2.8 mmol m72 s71,

while shade leaves in the lower foliage (1.8 m

height) at PFD as low as 27 mmol m72 s71

assimilated at a rate as low a 0.6 mmol m72 s71.

These assimilation rates are 27% and 6%, respec-

tively, of the estimated rate (10.3 mmol m72 s71)

for sun leaves. In a globelet-trained Manto Negro

vineyard, Escalona et al. (2003) found an assimila-

tion rate of about 13 mmol m72 s71 in the top

canopy leaves, and around unit for the inner leaves,

Figure 6. Spatial variation of the light interception (PFDInt, mmol m72 s71) measured over a grid of 0.160.2 m2 over the ground below the

UT, T50, and T75 canopies from early July to end of September 2002.

Figure 7. Leaf CO2 assimilation (Aest, mmol m72 s71) response to

PFD (mmol m72 s71), i.e. A/Q curve, in the control treatment as

modelled on the basis of the parameters found in September 2002

as reported in Table III for sun- and shade leaves. CO2 assimilation

is estimated at the PFD actually measured in the canopy profile on

8 September 2002 for sun leaves (top of canopy) and shade leaves at

2.0 and 1.8 m height (within the foliage).

Light environment and gas exchange in Tendone grapevines 331

Dow

nloa

ded

by [

Uni

v St

udi B

asili

cata

] at

03:

17 0

5 Ju

ly 2

012

indicating the small contribution capacity of the

latter leaves to canopy photosynthesis. Leaves in the

lowest (fourth) layer of a tendone canopy showed a

daytime mean photosynthetic rate as low as one-

third of that observed in the top layer leaves (de

Palma & Novello 2004). Our estimations clearly

indicate the poor photosynthetic activity of shade

leaves in tendone canopies. On the basis of light

response curves, Smart (1974) actually predicted

that in dense vineyard canopies most of the

photosynthesis is due to direct light absorbed by

the uppermost canopy layers. Only when the

incoming light above a vineyard was not less than

2000 mmol m72 s71, the second leaf layer would

receive light at 200 mmol m72 s71, well above the

light compensation point (Howell 2001). Similarly,

Weyand and Schultz (2006) estimated that the top

canopy portions of the vineyard contributed to most

of the carbon budget. Same authors also concluded

that the increased sink size (higher yield in MP

vines as compared with VSP vines) had only a small

stimulating effect on leaf photosynthesis rate as it

was probably offset by the increased LAI. In our

tendone, cluster thinning induced a significant

increase in LAI, although we observed no signifi-

cant difference in the assimilation between the

thinning treatments. Our results indicated that

Montepulciano grapevines showed a morphological

response to the alteration of the sink/source ratio

that was not accompanied by a physiological

response.

In conclusion, the tendone vineyard showed a

parallel increase between LAI and light interception

during the growing season until the execution of

summer pruning. At that time, the tendone canopy

of the UT treatment was capable of intercepting 75%

of the incoming radiation. Early thinning treatment

induced a strong increase in leaf area, but a modest

insignificant increase in light interception because of

the high shading of the upper over lower leaf layers.

With the occurrence of canopy closure, shade leaves

had a lower light-saturated photosynthetic CO2

assimilation than leaves at the top of the canopy,

but with no significant differences in the apparent

quantum yield of CO2 assimilation. We estimated

that the rate of CO2 assimilation at the measured

PDF ranged from 6 to 27% of the rate estimated for

the top canopy leaves.

Acknowledgments

This research was carried out within the framework

of the Italian Ministry for Education, University and

Research (MIUR) PRIN project entitled ‘‘Meto-

diche innovative per lo studio dei rapporti tra

struttura della chioma, radiazione e bilancio del

carbonio in Vitis vinifera L.’’

References

Baeza P, Ruiz C, Cuevas E, Sotes V, Lissarrague J-R. 2005.

Ecophysiological and agronomic response of Tempranillo

grapevines to four training systems. Am J Enol Vitic 56: 129–138.

Beis A, Patakas A. 2010. Differences in stomatal responses and

root to shoot signalling between two grapevine varieties

subjected to drought. Funct Plant Biol 37: 139–146.

Boardman NK. 1977. Comparative photosynthesis of sun and

shade plants. Annu Rev Plant Physiol 28: 355–377.

Cartechini A, Palliotti A. 1995. Effect of shading on vine

morphology and productivity and leaf gas exchange character-

istics in grapevines in the field. Am J Enol Vitic 46: 227–234.

Chapman DM, Matthews MA, Guinard J-X. 2004. Sensory

attributes of Cabernet Sauvignon wines made from vines with

different crop yields. Am J Enol Vitic 55: 325–334.

Charles-Edwards DA, Lawn RJ. 1984. Light interception by grain

legume row crops. Plant Cell Environ 7: 247–251.

DeLucia EH, Shenoi HD, Naidu SL, Day TA. 1991. Photo-

synthetic symmetry of sun and shade leaves of different

orientations. Oecologia 87: 51–57.

de Palma L, Novello V. 2004. Leaf water use efficiency in a

‘‘Tendone’’ trained canopy: a contribute to the ecophysiolo-

gical characterization of a grapevine growing system. Acta

Hortic 664: 155–161.

de Souza CR, Maroco JP, dos Santos TP, Rodrigues ML, Lopes CM,

Pereira JS, et al. 2003. Partial rootzone drying: regulation of

stomatal aperture and carbon assimilation in field-frown grape-

vines (Vitis vinifera cv. Moscatel). Funct Plant Biol 30: 653–662.

Dokoozlian NK, Kliewer WM. 1995. The light environment

within grapevine canopies. I. Description and seasonal changes

during fruit development. Am J Enol Vitic 46: 209–218.

Edson CE, Howell GS, Flore JA. 1995. Influence of crop load on

photosynthesis and dry matter partitioning of Seyval grape-

vines. II. Seasonal changes in single leaf and whole vine

photosynthesis. Am J Enol Vitic 46: 469–477.

Escalona M, Flexas J, Bota J, Medrano H. 2003. Distribution of

leaf photosynthesis and transpiration within grapevine canopies

under different drought conditions. Vitis 42: 57–64.

Fanelli L. 1965. Il Tendone. Ramo Editoriale degli Agricoltori.

Roma. pp. 150.

Giorio P, Basile A, Sorrentino G, Albrizio R. 2007. Physiological

responses of ‘Falanghina’ grapevines in soils with different

water availability in southern Italy. Acta Hortic 754: 235–239.

Givnish TJ. 1988. Adaptation to sun and shade: a whole plant

perspective. Aust J Plant Physiol 15: 63–92.

Gladstone EA, Dokoozlian NK. 2003. Influence of leaf area

density and trellis/training system on the light microclimate

within grapevine canopies. Vitis 42: 123–131.

Howell GS. 2001. Sustainable grape productivity and the growth-

yield relationship: A review. Am J Enol Vitic 52: 165–174.

Hunter JJ, Visser JH. 1989. The effect of partial defoliation, leaf

position and developmental stage of the vine on the photo-

synthetic activity of Vitis vinifera, L. cv. Cabernet Sauvignon. S

Afr J Enol Vitic 10: 67–73.

Intrieri C, Poni S, Lia G, Gomez del Campo M. 2001. Light

interception, gas exchange and carbon balance of different

canopy zones of minimally and cane-pruned field grown

Riesling grapevines. Vitis 40: 123–130.

Kliewer WM, Dokoozlian NK. 2005. Leaf area/crop weight ratios

of grapevines: influence on fruit composition and wine quality.

Am J Enol Vitic 56: 170–181.

Monteith JL. 1994. Discussion: validity of the correlation between

intercepted radiation and biomass. Agric Forest Meteorol 68:

213–220.

Morrison JC, Noble AC. 1990. The effect of leaf and cluster

shading on the composition of Cabernet Sauvignon grapes and

on fruit and wine sensory properties. Am J Enol Vitic 41: 1–8.

332 P. Giorio and V. Nuzzo

Dow

nloa

ded

by [

Uni

v St

udi B

asili

cata

] at

03:

17 0

5 Ju

ly 2

012

Naor A, Gal Y, Bravdo B. 2002. Shoot and cluster thinning influence

vegetative growth, fruit yield and wine quality of ‘Sauvignon

blanc’ grapevines. J Am Soc Hortic Sci 127: 628–634.

Palliotti A, Cartechini A, Ferranti F. 2000. Morpho-anatomical

and physiological characteristics of primary and lateral shoot

leaves of Cabernet Franc and Trebbiano Toscano grapevines

under two irradiance regimes. Am J Enol Vitic 51: 122–130.

Rana G, Katerji N, Introna M, Hammami A. 2004. Microclimate

and plant water relationship of the ‘‘overhead’’ table grape

vineyard managed with three different covering techniques. Sci

Hortic 102: 105–120.

Schultz HR. 1996. Leaf absorptance of visible radiation in Vitis

vinifera, L.: Estimates of age and shade effects with a simple

field method. Sci Hortic 66: 93–102.

Silvestroni O, Poni S, Intrieri C, Fontana M. 1993. Effects of light

regimes on chlorophyll concentration and gas-exchange in Vitis

vinifera L. Vitis 48: 96–100.

Sinclair TR, Muchow RC. 1999. Radiation use efficiency. Adv

Agron 65: 215–265.

Smart RE. 1973. Sunlight interception by vineyards. Am J Enol

Vitic 24: 141–147.

Smart RE. 1974. Photosynthesis by grapevine canopies. J Appl

Ecol 11: 997–1006.

Smart RE. 1985. Principles of grapevine canopy microclimate

manipulation with implications for yield and quality. A review.

Am J Enol Vitic 36: 230–239.

Smart RE. 1988. Shoot spacing and canopy light microclimate.

Am J Enol Vitic 39: 325–333.

Smart RE, Robinson M. 1991. Sunlight into wine. A handbook for

winegrape canopy management. Australia: Winetitles, Ade-

laide. pp. 88.

von Caemmerer S, Farquhar GD. 1981. Some relationships

between the biochemistry of photosynthesis and the gas

exchange of leaves. Planta 153: 376–387.

Weyand KM, Schultz HR. 2006. Light interception, gas exchange

and carbon balance of different canopy zones of minimally

and cane-pruned field-grown Riesling grapevines. Vitis 45:

105–114.

Williams LE. 1996. Grape. In: Zamski E, Schaffer AA, editors.

Photoassimilate distribution in plants and crops: Source-sink

relationships. New York: Marcel Dekker, Inc. pp. 851–881.

Light environment and gas exchange in Tendone grapevines 333

Dow

nloa

ded

by [

Uni

v St

udi B

asili

cata

] at

03:

17 0

5 Ju

ly 2

012