Abstract: Five years old grapevines of Early Cardinal, Trakya ilkeren, Ergin cekirdeksizi and Yalova Incisi grown in greenhouse were used. During three years, the effects of three different evaporation coefficient factors (kp1 = 1.0, kp2 = 1.3, kp3 = 1.6) on vines were investigated. Irrigation amounts calculated with respect to each evaporation factor were applied in 4-6 days intervals. In general, cluster weight and berry size were slightly increased with kp2 application while different irrigation levels had no significant effect on bud-break and berry ripening date both in cultivars and years. Considering earliness, grape yield, cluster and berry size, cultivars Early Cardinal and Yalova Incisi with irrigation level kp2 could be recommended for early grape production under greenhouse conditions.
INTRODUCTION
Mediterranean Region is the second biggest grape producing zone among agricultural regions of Turkey with the values of 103172 ha and 706105 ton, area and production, respectively (Celik et al., 2005). For open area grape production, harvesting begins in the middle of June in Cukurova Province (Ergenoglu, 1988; Tangolar et al., 1996). In the region, early ripening grape cultivars have always higher income and they have been therefore taking up the growers’ attention.
In viticulture researches, in order to obtain earlier crops, many applications have being carried out one of which is to grow vines under greenhouse conditions (Manzo, 1977; Lavee, 1988; Avenant and Loubser, 1994; Li and Zhang, 1994).
In Turkey, use of polyethylene (PE) cover in viticulture studies has been increasing and many researches have focused on the improvement of earliness. In some researches carried out by Uzun (1993), Uzun and Ozbas (1995) and Ergenoglu et al. (1998 and 1999), it was shown that ripening was earlier for 14-29 days than open field grown vines. These studies indicate that favorable conditions of Mediterranean Region induce growers to produce grape under PE coverage.
Grapes require certain amount of water in the soil for normal vegetative growth and maturity. In greenhouse production technique, which collects increasing interest of Cukurova grape growers, irrigation is required apart from open field grape growing. Under greenhouse condition, as the vines get limited rainfall water, additional irrigation after covering is necessary to obtain high quality of grapes. Furthermore in many researches, it was implied that additional water must be supplied in vineyards when the rainfall is not enough (Winkler et al., 1974; Weaver, 1976; Wildman et al., 1976; Cifre et al., 2005; Rana et al., 2004). For this reason, it is essential to highlight accurate applications and calculations such as irrigation procedures (Van Zyl and Van Hyssteen, 1988; Ergenoglu et al., 1992 and 1997), water consumption of vine (Bastug et al., 1998), irrigation times and water requirement (Grimes and Williams, 1990; Naor et al., 1993; Nadal and Arola, 1995; Rana et al., 2004; Zabihi, 2004; Keller et al., 2005; Reynolds et al., 2005).
In this study, the determination of the irrigation water requirement for vines grown under greenhouse conditions was aimed under Mediterranean type climate.
MATERIALS AND METHODS
This research was carried out in Research and Application Vineyard of Cukurova University, Agriculture Faculty, Horticulture Department during 2000-2002. In the study, guyot system trained Yalova incisi, Trakya ilkeren, Ergin cekirdeksizi and Early Cardinal cultivars with the density of 1.0x1.5 m were used.
| Table 1: | Irrigation requirements calculated with respect to total evaporation in different years (L vine-1) |
| * Total evaporation was measured between 18 May -12 June in 2000; 3 May-1 June in 2001; 16 March -31 May in 2002 | |
| Table 2: | Physical and chemical properties of the experimental area soil |
| *According to the Gunes et al. (2004) | |
Vines were grown in three equal sized PE greenhouse, 2.0 m in height, 30 m in length and 3.0 m in width, the PE containing UV+IR was 300 μm in thickness. In the middle of February, PE was covered on the greenhouses in which no additional heating system was installed. In the investigation the effects of three irrigation levels on grape yield and quality were compared under greenhouse. For irrigation, following equation suggested by Goldberg et al. (1976) was utilized: IR = kp. Epan.A.R where IR is the irrigation requirement (L. vine-1), kp evaporation coefficient [in the study kp1, kp 2 and kp 3 were used as 1.0 (whole amount of water equal to evaporation), 1.3 (whole amount with additional 30%) and 1.6 (whole amount with additional 60%), respectively)], Epan the amount of cumulative evaporation from class A-Pan during an irrigation interval (mm or L), A each plant area (1.5 m2) and R Percentage of wetted area (taken as 0.5). Irrigations were applied in 4-6 days intervals depending on evaporation amounts by drip irrigation system. Class A Pan was located at the experiment area.
Irrigation numbers, evaporation values and irrigation requirements with respect to irrigation applications were given in Table 1.
In drip irrigation system, laterals were laid on each plant row and droppers of 4 L h -1 capacity were arranged in 75 cm intervals on lateral lines.
The soil properties, based on 0-30 and 30-60 cm depths were Shown in Table 2. Only in 2002 year 50 kg N ha-1 as urea and 15 kg P2O5 ha-1 as phosphoric acid were applied to the experiment area as fertilizer.
The following parameters were examined to compare applications: Bud-break and ripening dates, yield (g vine-1), cluster weight (g), berry weight (g), berry volume (mL), total soluble solids (TSS, %), acidity (g 100 mL juice-1) (Anonymous, 1997). Fifteen vines were examined for each application in five replications. Variance analyses were done according to the ANOVA Randomized Complete Blocks for evaluation of data and the differences between average values were determined with LSD test.
RESULTS AND DISCUSSION
As can be seen in Table 3, bud-break dates varied from season to season due to alteration in responses of cultivars to climatic conditions. Different irrigation levels applied in greenhouse both in cultivars and years had no significant effect on bud-break and ripening date. Trakya Ilkeren and Early Cardinal were earlier than the others in both ripening and bud break dates ( Table 3).
On the other hand, cluster and berry weights with yield were affected from
applications ( Table 4 and 5). In general
kp2 level were slightly increased these characteristics. Differences were evident
between cultivars. The biggest and the smallest clusters were obtained with
Ergin cekirdeksizi and Trakya ilkeren, respectively. By the determination of
grape yields, kp1 and kp2 gave higher results with all cultivars. Differences
among the different cultivars affected the general mean value. Early Cardinal
surpassed the others significantly about the yield. With the evaluation of about
6000 vines per hectare with density of 1.5x1.0 m, grape yields were 10470 kg
ha-1 with Trakya ilkeren; 17904 kg ha-1 with Ergin cekirdeksizi
and 22398 kg ha-1 with Yalova Incisi, while Early C ardinal had the
yield as high as 24918 kg ha-1. Considering the mean grape production
value of Turkiye (6792 kg ha-1) (Celik et al., 2005) with
its important regions Aegean (8924 kg ha-1) and Mediterranean (6844
kg ha-1) (Celik et al., 2005) and some leading cities (Izmir,
8260 kg ha-1) (Nevsehir, 8130 kg ha-1), these yield values
of the study were fairly high.
| Table 3: | Effects of different applications on bud break and ripening dates (day month) |
| 1kp1 = 1.0; kp2 = 1.3; kp3 = 1.6 | |
| Table 4: | Effects of different applications on cluster weight and grape yield of cultivars |
| 1kp1=1.0; kp2=1.3; kp3=1.6; 2NS, Not Significant; **p<0.01; *p<0.05; differences between means in the same column indicated by the same letter (s) are not statistically significant | |
As the irrigation applications commenced in 2002 was earlier (16th March, twenty days after bud break) than the other experimental years, increases in yield, cluster weight and berry size were recorded ( Table 4 and 5). These increases possible were due to much more water applications per vines during 2002 period ( Table 1).
Evaluation results of application on 100 berry weight (g) and volume (mL) were
presented in Table 5. The biggest berries (5.47 g and 5.18
mL) were obtained with Early cardinal with respect to mean value of 3 year study.
Significant differences in TSS and acidity grades were found between Irrigation
treatments and cultivars ( Table 6). Irrigation applications
had slight influence on TSS and acid content of berry must. By the investigation
of general mean values regarding to effect of irrigation applications, it could
be shown that kp2 level provided better results than kp1 and kp3 level.
| Table 5: | Effects of different applications levels on berry weight and volume of cultivars |
| 1kp1=1.0; kp2=1.3; kp3=1.6; 2 NS, Not Significant; **p<0.01; *p<0.05; differences between means in the same column indicated by the same letter (s) are not statistically significant | |
| Table 6: | Effects of different applications on TSS and acidity characteristics of cultivars |
| 1kp1=1.0; kp2=1.3; kp3=1.6; 2NS, Not Significant; **p<0.01; *p<0.05; differences between means in the same column indicated by the same letters are not statistically significant | |
CONCLUSIONS
At the end of the study, by going through the observed ripening dates of especially Trakya ilkeren and Early Cardinal grown under the greenhouse conditions, these cultivars could be recommended for early table grape production.
Upon the results of this study, it can be concluded that it is useful to maintain viticulture researches about this subject by using different cultivars and conditions and to disclose the best applications with other researches comparatively. It is considered that there is an existence of linear relationship between vine age and effectiveness of irrigation. It is also suggested that the lower coefficient factor than kp = 1.6 in irrigation levels and the irrigation must start prior or at the bud break with the consideration of early covering. Different irrigation times and intervals also must be examined in greenhouse viticulture.