¥Agronomia vol. 6 n. 2 July

Ital. J. Agron., 6, 2, 119-126 

Effects of Water Regime on Fatty Acid Accumulation and Final Fatty Acid 

Composition in the Oil of Standard and High Oleic Sunflower Hybrids 

M. BALDINI, R. GIOVANARDI, S. TAHMASEBI-ENFERADI, and G.P. VANNOZZI † 

Dipartimento di Produzione Vegetale e Tecnologie Agrarie, Università di Udine, Udine, Italy 

Corresponding author: M. Baldini, Dipartimento di Produzione Vegetale e Tecnologie Agrarie, Università di 

Udine, via delle Scienze 208, 33100 Udine, Italy. Tel.: +39 0432 558663; Fax: +39 0432 558603; E-mail: baldini@dpvta.uniud.it 

Received: 4 June 2002. Accepted: 7 October 2002. 

ABSTRACT 

BACKGROUND. Little has been done to study the effects 

of agronomic factors on the fatty acid composition 

in sunflower oil and in particular, the effect of 

water availability is more or less unknown. This research 

studied the effect of water availability on fatty 

acid accumulation and final fatty acid composition 

in the oil in high oleic and standard sunflower hybrids. 

METHODS. Lysimeter trials were carried out during 

1997 and 1998 to study the effects of different water 

regimes on fatty acid composition and accumulation 

in high oleic and standard sunflower hybrids. The water 

regimes adopted were: water table, replacement 

of the evapotranspiration (ET) and water stress. Two 

hybrids were cultivated: UD12, with a high oleic content 

and UD87 as standard, both obtained by the Crop 

Production Department of Udine University. A randomised 

block design was used with four and two replications, 

in the first and second year, respectively, and 

the main yield characteristics were evaluated at maturity. 

Achene samples were collected, every 6 days, from 

last anthesis until maturity in order to study achene dry 

weight, oil and fatty acids accumulation. 

RESULTS. In the standard and high oleic hybrids the 

fatty acid composition stabilised between the 17th and 

23rd day after the end of flowering and in the standard 

hybrid the ratio between oleic and linoleic fatty 

acids reached a value very close to one. Water 

stress significantly increased oleic acid content (of approx. 

5%) with respect to the other water regimes in 

the high oleic hybrids during both years, reducing the 

dry matter and oil accumulation phases, with all the 

enzyme activities involved, including ∆-12 desaturase, 

which is responsible for the desaturation from oleic 

to linoleic acid. 

CONCLUSION. Water stress, causing accelerated and 

earlier embryo development and lipid accumulation 

therefore determines a shorter duration of all enzy- 

matic activities, including those of ∆-12 desaturase 

and this could reflect on the final acid composition. 

This hypothesis could also explain some inconsistent 

qualitative results of the high oleic hybrids obtained 

in different years and environments. 

INTRODUCTION 

The nutritional quality of sunflower oil is due 

to the high percentage of C:18 fatty acids, in particular 

linoleic (18:2) and oleic acid (18:1), which 

together represent about 90% of the fatty acid 

total, with the remainder being made up of 

palmitic (C16:0) and stearic acid (C18:0). From 

1977 onwards, after the FAO published results 

on the possible negative effects of some fats and 

oils on human health, interest in polyunsaturated 

fatty acids of plant origin grew and there 

have been many studies done to determine the 

effect on health of the different fatty acids in 

the diet. In general a diet rich in vegetable oils 

prevents heart disease (Krajcovicova- Kudlakova 

et al., 1997). In particular, a diet rich in 

mono-unsaturated fatty acids reduces the cholesterol 

level associated with low-density 

lipoproteins (“harmful cholesterol”) and has no 

effect on the level of the triglycerides or on the 

cholesterol associated with high density lipoprotein, 

if compared to a diet rich in saturated fatty 

acids (Grundy, 1986). Other more recent 

studies have reached the same conclusion: a diet 

intended to prevent cardiovascular disease 

must include a reduction in saturated fatty acids 

intake (Jing et al., 1997) and these should not 

provide more than 30% of the energy supplied 

by fats (Woo et al., 1997). 

† The work can be attributed in equal parts to the authors M. Baldini, R. Giovanardi and G.P. Vannozzi. S. Tahmasebi- 

Enfradi was responsible for the section on chemical analyses.

120 Baldini et al. 

Recent studies have verified the antioxidant 

properties of oleic acid (Berry and Rivlin, 1997) 

and have demonstrated that an increase in the 

oleic acid content in the tissues, in situations of 

high oxygen stress (oxygen toxicity), can contribute 

towards forming better cellular protection 

than a similar increase in polyunsaturated 

fatty acids (Kinter et al., 1996). Other studies 

done on the Chinese population in Hawaii have 

highlighted an inverse relationship between the 

consumption of monounsaturated fatty acids 

and cancer of the colon (Po Huang et al., 1996). 

For some years research has been underway 

with the aim of obtaining new high oleic varieties 

of sunflower, which has thoroughly tackled 

the problems related to the genetic control 

of high oleic acid content (Miller et al., 1987; 

Alonso, 1988; Fernandez-Martinez et al., 1989), 

lipid biosynthesis in both standard genotypes 

and those with a high oleic acid content in the 

achenes (Ohlrogge et al., 1991; Ohlrogge and 

Browse, 1995) and the effect of the main environmental 

factors (temperature in particular) 

that can modify the linoleic/oleic acid ratio in 

the oils (Harris et al., 1978; Goyne et al., 1979) 

due to the well-known affect on enzyme activity 

(oleoyl phosphatidylcholine desaturase or 

∆ -12 desaturase) that converts oleic acid into 

linoleic acid (Garces et al., Garces and Mancha, 

1989, 1001). Little has been done to study the 

effects of other agronomic factors on the fatty 

acid composition. In particular, the effect of water 

availability is more or less unknown, except 

for the study by Talha and Osman (1975) carried 

out before the existence of high oleic hybrids. 

This research studied the effect of water availability 

on fatty acid accumulation and final fatty 

acid composition in the oil in high oleic and 

standard hybrids. 

MATERIALS AND METHODS 

Two trials were done in 1997 and 1998 at the 

Experimental Farm of Udine University (46° 02’ 

N, 13° 13’ E and 110 m a.s.l.), using two different 

lysimeter systems. In 1997 12 underground 

lysimeters were used (length 1.1 m, width 0.8 m 

and depth 0.70 m). The lysimeters were filled 

with loam soil (20, 42 and 38% of clay, silt and 

sand, respectively) (0.5 m layer) and with sand, 

gravel and fine pebbles (0.2 m layer) for 

drainage and were protected from the rain by 

a transparent fixed canopy. In 1998 larger 

lysimeters were used (1.5 × 1.5 × 1.5 m), containing 

the same soil and protected from the 

rain by a mobile canopy on rails (12 lysimeters 

of which 2 were weighing, 4 with automatic regulation 

of water table depth and 6 drainage 

ones). The main climatic characteristics, divided 

into the pre- and post-flowering stages of the 

crop, were recorded at an automatic weather 

station close to the experiment (Table 1). As regards 

the water regimes reported in Table 2, it 

should be specified that the water table, where 

involved, was maintained through hypogeal water 

refills at a constant depth of 0.5 m in the 

first year and 0.6 m in the second; that 60% and 

100% ET represent the percentages of restoration 

of evapotranspiration (ETM) by means of 

hypogeal irrigation, in the first and second year, 

respectively, and that stress means no water 

restoration from flowering to physiological maturity. 

The field capacity (-0.02 MPa) and wilting point 

(-1.5 MPa) of the soil were measured in the laboratory 

as being 30 and 15% of soil volume, respectively. 

The soil water content in each lysimeter 

was measured every 3 days by TDR (Tektronics 

1502C) using probes inserted at 20 and 

40 cm depths and by oven-drying soil samples 

from the same depths every 15 days. The infor- 

Table 1. Weather conditions during the experiments. Average values of minimum temperature (Min T), maximum temperature 

(Max T), relative humidity (RU), solar radiation (Radiation) and rainfall (Rainfall) during sowing – end of flowering 

and end of flowering – physiological maturity periods. 

* Rainfall has not affected the trials 

Year Period Min T Max T RU Radiation Rainfall 

(°C) (°C) (%) (MJ m -2 day -1 ) (mm) * 

1997 Sowing (04/04) – end flowering (06/07) 11.1 20.7 64.6 19.4 469 

End flowering – physiol. maturity (06/08) 15.1 26.2 70.8 22.0 105 

1998 Sowing (06/05)- end flowering (28/07) 12.4 25.3 68.6 21.7 265 

End flowering – physiol. maturity (30/8) 17.3 29.3 65.2 21.1 91

mation obtained from the TDR probes, placed 

on all the lysimeters, was integrated with the 

values obtained from the two weighing lysimeters 

to identify when to irrigate. 

Two sunflower hybrids were used, one with a 

high oleic content (UD12) and the other a standard 

one (UD87), both characterised by the 

same crop cycle and selected by the Crop Production 

Department at the University of Udine 

(in the first year only the high oleic hybrid was 

used). Sowing was done on 04/04/1997 and 

02/04/1998; after thinning 6 plants m -2 remained 

(6 plants per lysimeter in 1997 and 15 per 

lysimeter in 1998). Base fertilisation was done 

with 150 kg of P 2 O 5 and 200 kg of K 2 O. At the 

B6 stage (Merrien, 1986), a side dressing was 

done with approx. 120 kg of N in the form of 

ammonium nitrate. Two treatments against 

aphids were required in the first year. During 

both years weeds were hand removed when necessary. 

At flowering all the heads of the high 

oleic hybrid were protected with nylon mesh to 

avoid cross pollination by insects, but that allowed 

the passage of air and water so as to avoid 

forming a specific microclimate around the head 

that would interfere with the biochemical and 

physiological activity of the forming achenes. The 

high self-compatibility of the genotype allowed 

full fertilisation of the flowers. 

The experimental layout was a randomised 

block design, with 1 genotype (UD12), 3 irrigation 

treatments (restoration of 60% of ETM, 50 

cm deep water table and stress) and 4 replicates 

in the first year and 2 genotypes (UD12 and 

UD87), 3 irrigation treatments (restoration of 

Fatty Acids in Sunflower Hybrids 121 

Table 2. Treatments adopted and analysed characters on sunflower hybrids at harvest time. 

Means with same letters are not significantly different P ≤ 0.05 (Duncan test). 

(1) 60 and 100% ET= restoration of 60 and 100% of ETM; Table 0.5 and 0.6 m= water table depth; Stress= no water 

restoration from flowering to physiological maturity. 

Year Hybrids Water regime (1) Achene yield Single achene Achenes per Oil content 

(g m -2 ) weight (mg) plant (n°) (% s.s.) 

1997 High oleic 60% ET 328 b 42.3 ac 1033 b 45.5 ab 

“ “ Table 0.5 m 512 a 45.2 ac 1510 a 43.5 ab 

“ “ Stress 144 c 25.8 bc 2743 c 42.2 ab 

1998 High oleic 100% ET 513 a 48.3 ac 1326 b 40.9 bb 

“ “ Table 0.6 m 540 a 46.5 ac 1453 a 47.2 ab 

“ “ Stress 304 c 40.6 bc 2936 c 43.5 ab 

“ Standard 100% ET 493 ab 43.5 ab 1416 a 39.4 bb 

“ “ Table 0.6 m 432 b 44.6 ab 1210 b 45.9 ab 

“ “ Stress 235 d 39.9 bc 2737 d 42.8 ab 

100% of ETM, 60 cm deep water table and 

stress) and 4 replicates, in the second. 

At harvest, the achenes, after oven drying (72 

hours at 50 °C), were used for the following determinations: 

− achene production per unit surface area (g m -2 ); 

− achene unit weight (mg); 

− filled achenes per plant (n); 

− oil content in the achenes (% of dry weight), 

using the NMR (Nuclear Magnetic Resonance) 

method. 

Six samples of 10 achenes were taken from each 

treatment starting at 5 days from the end of 

flowering, stage F4 (Merrien, 1986), until maturity, 

stage M3 (Merrien, 1986). The samples were 

taken from four plants (one plant per lysimeter 

in the first year and two plants in the second, 

respectively), always from the external zone of 

the head. The achenes were immediately ovendried 

(72 hours at 60 °C) and stored in a cold 

room (4 °C) until the end of the trial. 

On each of these samples the following determinations 

were made: 

− whole achene unit weight (in the second 

year) (mg); 

− oil content (% of dry weight), following the 

method used by Champolivier and Merrien 

(1996) (in the second year), by hexane extraction; 

− percentage content of the major fatty acids 

in the oil: stearic acid (C16:0), palmitic acid 

(C18:0), oleic acid (C18:1) and linoleic acid 

(C18:2), using the esterification and gas-chromatography 

methodology described by Fernandez 

et al. (1999).


Analysis of variance was done on the data, and 

when the F test proved significant, Duncan’s 

test at P ≤ 0.05 was used to separate the mean 

values of the treatments. For the data from the 

samples taken during the crop cycle the sources 

of variation were water regime and sampling 

date in the first year, and water regime, hybrid 

and sampling date in the second. 

RESULTS AND DISCUSSION 

Figure 1 shows achene dry matter accumulation 

during maturation. As the statistical analysis 

demonstrated that the hybrid effect was not significant, 

the values reported are the means of 

the two hybrids. It should be pointed out that 

at the first sampling (two days after the end of 

flowering), the embryo begins to form and 

therefore all the values relating to that date refer 

principally to the tissues of the seed coat, 

which forms and develops independently of fertilisation. 

The most significant increase in dry 

weight took place between 8 and 14 days after 

flowering, while between 20 and 28 days dry 

matter accumulation in the achene is more or 

less completed. Between treatments, water 

stress determined the formation of lighter achenes 

at maturity compared to the other treatments, 

with a higher growth rate in the earliest 

stages (8 days after fertilisation), thus confirming 

the findings of Hall et al. (1985). Figure 2 

shows a strong increase in oil accumulation in 

the achene (the values are the mean of the two 

hybrids), between the 8th and 14th days after fertilisation, 

in correspondence to the significant 

Figure 1. 1998. Time course of dry matter accumulation in 

achenes of plants submitted to water table (), ET () and 

stress () water regimes. The values reported refer to the 

mean of the two cv. The vertical bars represent the standard 

error of the mean. 

Figure 2. 1998. Time course of oil accumulation in achenes 

of plants submitted to water table (), ET () and stress 

() water regimes. The values reported refer to the mean 

of the two cv. The vertical bars represent the standard error 

of the mean. 

increase in dry matter in the achene (Figure 1). 

Among water regimes, the supply from the water 

table determined, at maturity, significantly 

higher percentages of oil in the achene than in 

the other irrigation regimes. However, all treatments 

reached the maximum oil content on the 

20 th day after the end of flowering, confirming 

what Champolivier and Merrien (1996) found 

in a trial conducted in a phytotron at the highest 

temperatures (27 °C day and 22 °C night), 

which are roughly equivalent to those at the trial 

site during post-flowering (Table 1). 

Figures 3 and 4 give the accumulation of the 

major fatty acids in the oil of the high oleic and 

standard hybrids for both years. 

In the first year of the trial the saturated fatty 

acids content (palmitic and stearic) in the high 

oleic hybrid diminished rapidly in the days following 

the end of flowering, to then stabilise between 

the 17 th and 23 rd day at approx. 2.5 and 

4%, respectively (Figure 3). The oleic acid content 

at the first sampling (74%) was significantly 

lower than that found at full-ripening (85%), 

while linoleic acid, on the contrary, had a value 

of 10% at the first sampling against 5% at maturity. 

Both these fatty acids stabilised between 

the 17 th and 23 rd day after the end of flowering 

(Figure 3). 

In the second year the palmitic acid trend 

seemed analogous in the two hybrids, with a 

slightly higher final amount in the standard hybrid 

(5.5%) than in the high oleic one (3%). 

This fatty acid reduced, compared to the initial

values, by circa 50% in the standard hybrid and 

33% in the high oleic one (Figure 4) between 

the 8 th and 14 th day after fertilisation. 

The stearic acid content, which follows the 

palmitic acid formation in the biosynthetic chain 

by the addition of two carbon atoms, was practically 

identical at maturity in the two hybrids 

(4.1 and 4.3% in the high oleic and standard hybrid, 

respectively). This fatty acid showed a significant 

increase from the 2 nd to 8 th day after fertilisation, 

due to the fact that the embryo has 

already begun to develop and also differentiates 

in the fatty acid composition from that of the 

tissues in the seed-coat, typical of the polar 

lipids and suitable for the membrane activities. 

From the 8 th day, with the biosynthesis increase 

in the oil, the ∆-9 desaturase enzyme is activated, 

which causes the formation of oleic acid 

(C18:1) through desaturation of stearic acid 

(C18:0). This was clearly seen in the standard 

hybrid where, besides a higher increase in oleic 

acid, there was a contemporary reduction in 

the linoleic acid content (Figure 4). Starting 

from the 14 th day, the action of the ∆-12 desat- 


Figure 3. 1997. Time course of fatty acids accumulation in a high oleic hybrid. The vertical bars represent the standard error 

of the mean. 

urase enzyme became evident, shown by an increase 

in linoleic acid (C18:2) and respective reduction 

of oleic acid (Figure 4). In the standard 

hybrid the ratio between these two fatty acids 

stabilised at around the 28 th day after the end 

of flowering, on a value very close to one (44.2 

and 45.3%, respectively) (Figure 4). The oleic acid 

percentage in the standard hybrid was in agreement 

with values obtained in the same environment 

in previous studies (Fernandez et al., 1999) 

and in experiments done in controlled environments 

with similar temperatures (Champolivier 

and Merrien, 1996). This could be attributed to a 

partial inhibition of ∆-12 desaturase activity 

caused by high temperatures, as found by Garces 

and Mancha (1991), who demonstrated an increase 

in desaturase activity between 10 °C and 

20 °C and a fast reduction as the temperature rose 

above this (activity reduced to one third at 30 °C 

and almost nil at 35 °C). 

In both hybrids the oleic and linoleic acid values 

at the first sampling were more similar than 

the final values (Figure 4), as reported by other 

authors (Garces and Mancha, 1989). This


Figure 4. 1998. Time course of fatty acids accumulation in the two sunflower cv, high oleic () and standard (). The value 

reported refers to the mean of the treatments. The vertical bars represent the standard error of the mean. 

could be attributed to two causes: the first is 

that in both sunflower hybrids, oleic acid is the 

major constituent of the tissues in the pericarp 

(Garces et al., 1989), as shown in Figure 4, and 

the second is that in the high oleic mutants, the 

∆-12 desaturase enzyme inhibition due to a different 

arrangement of the nucleotide sequences 

linked to the OL locus in the transcription of 

the responsible gene (Hongtrakul et al., 1998) 

is not immediate and instant. In fact, the constant 

and definitive levels for these fatty acids 

are reached between the 14 th and 20 th day after 

fertilisation (Figure 4). 

The differences in fatty acid composition in the 

high oleic hybrid between the two years, especially 

in the early seed development stages, can 

be attributed to the fact that the sampling times 

do not coincide and that the treatments also differ 

in the methods used. 

In the first year of the trial, better yield results 

were achieved with the shallow water table than 

with water stress or 60% restoration of the 

ETM, with both a higher achene unit weight and 

more filled achenes per plant (Table 2). 

In the second year the shallow water table and 

complete restoration of ETM gave the best 

yield results for both hybrids, even if the standard 

hybrid had a lower yield potential than the 

high oleic one in the water table and water 

stress treatments. It is interesting that the two 

most favourable water regimes, water table 

Figure 5. 1997-1998. Effect of water regimes on oleic acid 

(❒) and linoleic acid () content in the achenes at harvest 

time.

presence and complete ETM restoration led to 

the highest and the lowest oil content in the 

seeds, respectively, while water stress gave an intermediate 

result (Table 2). 

At harvest, the saturated fatty acid content 

(palmitic and stearic) did not vary in relation to 

water regime. However, in both years there was 

a positive and significant effect of water stress 

on the oleic acid content in the high oleic hybrid 

(increase of about 5%) (Figure 5). Instead, 

in the second year water stress determined a significant 

reduction of approx. 15% in oleic acid 

content compared to full irrigation restoration 

(100% ET) in the standard hybrid (Figure 5). 

CONCLUSIONS 

Different soil water availability during the flowering-maturity 

stage appeared to significantly 

influence the oleic acid content at harvest in 

both genotypes, standard and high oleic. In particular, 

in both years of the trial, water stress 

determined an increase in the oleic acid content 

in the high oleic hybrid compare to the other 

treatments. In the standard sunflower the ∆-12 

desaturase activity lasted longer, being almost 

identical to the end of flowering-maturity 

stages and can therefore be influenced by different 

or varying temperature conditions, towards 

which it is extremely sensitive. It is another 

matter in the high oleic sunflower where 

the same enzyme only shows some activity in 

the earliest stages of embryo development (until 

approx. 12 days after the end of flowering) 

associated with active lipid synthesis, to then 

lower abruptly towards negligible values 

(Garces and Mancha, 1991; Ohrlogge et al., 

1991). Water stress, causing accelerated and 

earlier embryo development and lipid accumulation 

(Figures 1 and 2) therefore determines 

a shorter duration of all enzymatic activities, 

including those of ∆-12 desaturase and 

this could reflect on the final acid composition. 

This hypothesis, which could also be extended 

to any type of environmental stress (e.g. temperature) 

that can affect the period of accumulation 

and that requires to be confirmed by 

further experiments, could also explain some 

inconsistent qualitative results of the high oleic 

hybrids obtained in different years and environments 

(Monotti et al., 1992; Del Pino et al., 

1996; Salera and Baldini, 1998), when significant 

genetic factors have not intervened. 

ACKNOWLEDGEMENTS 

Research carried out with financing from CNR 

(Italian Research Council), as part of the Coordinated 

Project GRU.S.I, and from the 

Province of Udine. 

The authors would like to thank Fabio Zuliani 

and Romina Carpi for their valuable collaboration 

in the technical management of the trials. 

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EFFETTO DEL REGIME IDRICO DEL TERRENO SULL’ACCUMULO DI ACIDI GRASSI 

E SULLA COMPOSIZIONE ACIDICA FINALE DELL’OLIO OTTENUTO DA IBRIDI DI 

GIRASOLE A BASSO E ALTO CONTENUTO DI ACIDO OLEICO 

SCOPO. Molto limitati sono gli studi effettuati per studiare l’importanza dei fattori egronomici sulla composizione 

acidica dell’olio nel girasole e tra questi, l’effetto della disponibilità idrica risulta quasi sconosciuto. 

METODO. Durante il 1997 e 1998, sono state effettuate due prove, in lisimetri protetti dalla pioggia da tettoie fisse 

e mobili. Tra gli obiettivi considerati, notevole importanza è stata attribuita alla valutazione dell’influenza della disponibilità 

idrica sulla composizione acidica finale dell’olio in ibridi normali ed ad alto oleico e sulla cinetica di 

accumulo dei principali acidi grassi. I regimi idrici adottati sono stati: alimentazione idrica da falda freatica; reintegro 

dell’evotraspirazione (ET) e stress idrico. I due ibridi sperimentali utilizzati sono stati UD12, ad alto oleico 

e UD87 normale, entrambi ottenuti dall’Università di Udine. Sono stati controllati i consumi idrici della coltura e 

lo stato idrico del terreno; sono stati analizzati l’accumulo di sostanza secca, di olio, e la composizione acidica degli 

acheni; a maturazione sono stati analizzati i principali caratteri produttivi. 

RISULTATI. La definitiva composizione acidica, in entrambi gli ibridi, viene raggiunta tra i 17 e 23 giorni dopo fine 

fioritura ed il rapporto tra oleico e linoleico, nell’ibrido “normale”, si è stabilizzato su un valore molto prossimo 

all’unità (44,2 e 45,3%, rispettivamente). In entrambi gli anni, nell’ibrido ad alto oleico, si è osservato un effetto significativo 

e positivo dello stress idrico sul contenuto di acido oleico nel seme alla raccolta rispetto agli altri trattamenti 

(aumento di circa il 5%). Lo stress idrico, ha provocato una accelerazione ed un anticipo nello sviluppo 

dell’embrione e nell’accumulo dei lipidi. 

CONCLUSIONE. Lo stress idrico, determinando una riduzione nel tempo di tutte le attività enzimatiche, compresa 

quella della ∆-12 desaturasi, responsabile della trasformazione da oleico a linoleico, può aver interferito direttamente 

nella composizione acidica finale. Tale ipotesi, che potrebbe anche essere allargata a qualsiasi tipo di stress 

ambientale (temperatura) capace di influenzare il periodo di accumulo, potrebbe anche spiegare alcuni incostanti 

risultati qualitativi di ibridi ad alto oleico ottenuti in diversi anni ed ambienti. 

Key-words: sunflower, water regimes, fatty acid composition, high oleic, ∆-12 desaturase.

¥Agronomia vol. 6 n. 2 July

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