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Pomological and vegetative changes during transition from flood irrigation to drip irrigation: Starkrimson Delicious apple variety
Scientia Horticulturae 136 (2012) 17–23
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Pomological and vegetative changes during transition from flood irrigation to drip irrigation: Starkrimson Delicious apple variety Cenk Küc¸ükyumuk a,∗ , Emel Kac¸al a , Ahmet Ertek b , Gökhan Öztürk a , Yasemin S. Kukul Kurttas¸ c a
E˘girdir Fruit Growing Research Station, 32500 Isparta, Turkey Süleyman Demirel University, Faculty of Agriculture, Department of Agricultural Structures and Irrigation, Isparta, Turkey c Ege University, Faculty of Agriculture, Department of Agricultural Structures and Irrigation, 35100 I˙ zmir, Turkey b
a r t i c l e
i n f o
Article history: Received 5 September 2011 Received in revised form 4 December 2011 Accepted 8 December 2011 Keywords: Apple Drip irrigation Flood irrigation Fruit quality Vegetative growth
a b s t r a c t Considering that apple growers have commonly used flood irrigation method instead of drip irrigation for many decades, this study aims to determine the effects of transition from flood irrigation to drip irrigation on vegetative growth and fruit quality (fruit diameter, length, weight, colour, firmness and classification). An apple orchard which had been irrigated by flood irrigation for many years was used for the study, during which flood irrigation was continued in one section as a control treatment, while drip irrigation was applied for rest of the apple orchard. Two different irrigation intervals (4 and 7 days) and four different pan coefficients (0.50, 0.75, 1.0, 1.25) were applied during drip irrigation treatments. Flood irrigation included only one treatment (20 days irrigation interval). Transition to drip irrigation method for apple trees indicated positive consequences on vegetative growth and fruit quality. Fruit diameter, length and weight values were the highest in Kcp3 (1.0) treatments in drip irrigation. Kcp3 treatments also showed the highest red colour density values. Kcp3 and Kcp4 (1.25) represented a more marketable fruit size (extra and class 1) than flood irrigation. Lower amount of irrigation water was consumed with drip irrigation compared to flood irrigation. To obtain the highest quantity of marketable apples, Kcp treatment with 1.0 and irrigation interval with 4 days (I1 Kcp3 treatment) is recommended during transition from flood irrigation to drip irrigation for similar climatic and soil conditions. © 2011 Elsevier B.V. All rights reserved.
1. Introduction Water is consumed plentifully for agricultural purposes in Turkey and in the World (approximately 70%). Nevertheless, the rate of water consumption for industrial and domestic needs is gradually increasing and the rate of water consumption for agricultural irrigation is decreasing (Önder et al., 2005) that necessitate a more efficient use of available water resources. Consequently, irrigation methods with a contribution on saving water (drip irrigation method, etc.) should be used more. Surface irrigation methods (flood irrigation, etc.) have been used extensively in fruit growing, and transition to drip irrigation method has started being preferred more in recent years. Because drip irrigation method offers certain advantages such as fruit quality, decreasing labour costs, saving irrigation water, etc., many fruit growers have adopted this method. The adoption of drip irrigation method has expanded further especially at the regions with limited water resources. However, fruit growers who began to
∗ Corresponding author. Tel.: +90 246 3132420; fax: +90 246 3132425. E-mail address: [email protected] (C. Küc¸ükyumuk). 0304-4238/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.scienta.2011.12.012
employ drip irrigation reported decreasing fruit quality, weak vegetative growth and lower yield. Therefore, the effects of changing the irrigation method on fruit quality, vegetative growth and yield should be examined and an irrigation schedule should be designed. Apple is one of the most important fruits produced in Turkey. Apple production in Turkey is estimated as 3.9% of the world apple production (Anonymous, 2011a). Isparta, Karaman, Ni˘gde, Antalya and Denizli are the leading apple growing areas. Isparta is a very important apple growing region of Turkey with a production accounting for nearly 22% of the country’s total (Anonymous, 2011b). Apple growers have certain problems about growing techniques, especially irrigation. Drip irrigation method has been preferred for irrigating apple orchards in recent years. Albeit, some growers have continued employing flood irrigation as they think that transition to drip irrigation has negative effects on fruit quality and vegetative growth. This study identifies the effects of transition from flood irrigation method to drip irrigation on fruit quality and vegetative growth. At the same time, the study also aims to determine the most suitable irrigation scheduling for high fruit quality and vegetative growth in drip irrigation method.
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2. Materials and methods 2.1. Study area and plant material This study was carried out in E˘girdir Fruit Growing Research Station (37◦ 49 17.97 N, 30◦ 52 22.44 E), Isparta, Turkey during 2008 and 2009 growing seasons. The research area has a transition climate between the Mediterranean and Central Anatolia. The orchard soil was clay loam. Apple trees were planted in 1988 (5 m × 4 m spacing) and Starkrimson Delicious variety grafted onto seedling rootstock was used in the study. 2.2. Irrigation treatments The orchard had been irrigated by flood irrigation method until the beginning of this study (2008). During the study, flood irrigation treatment was considered as a control treatment in order to determine the effects of changing the irrigation method on fruit quality and vegetative growth of apple trees. Flood irrigation treatment was a part of the orchard and different irrigation programmes in drip irrigation were applied on the rest of the orchard. Two different irrigation intervals (I1 = 4 days, I2 = 7 days) and four different pan coefficients (Kcp1 = 0.50, Kcp2 = 0.75, Kcp3 = 1.00, Kcp4 = 1.25) were used for drip irrigation treatments. Only one irrigation interval (20 days) was used for flood irrigation treatment because apple growers commonly use 20 days as irrigation interval in the district. The results of the analysis of the irrigation water used in the study are given in Table 1. Classification was realized according to the US Salinity Laboratory Graphical System. According to this system, the salinity values of the irrigation water, which are in 250–750 EC × 106 range, are included in category C2 , and in category S1 in terms of SAR value (USSL, 1954). Irrigation water was C2 S1 class, which is suitable for irrigation. Irrigation water was supplied from an irrigation canal by a pump. The lateral pipes having 16 mm diameter were laid down on both sides of each row of trees. Emitter spacing on lateral sides was 0.75 m with all emitters having a discharge rate of 4 l h−1 . The plots in flood irrigation treatment were embanked in order to prevent water overflow. Irrigation quantities were based on pan evaporation (Epan ) from class-A pan for drip irrigation treatments. Evapotranspiration was calculated according to the following water balance method (Eq. (1)) (James, 1988) for each treatment of drip irrigation. The moisture of soil was measured before each irrigation and the applied irrigation water amount during each irrigation was noted. During the next irrigation, the soil moisture was measured and the difference was recorded as “plant water consumption” of that treatment. Et = Ir + R + Cr − Dp − Rf ± s
(1)
where Et is the evapotranspiration (mm), Ir is the amount of irrigation water (mm), R is the rainfall (mm), Cr is the capillary rise (mm), Dp is the water loss by deep percolation (mm), Rf is the surface run-off (mm), and s is the change in profile soil water content (mm). Cr values were considered as zero as there were no ground water problems in the area. Dp was ignored since the amount of water applied through irrigation was not above the field capacity. Rf was not taken into account either as the total water amount applied through irrigation was measured for each irrigation. Irrigation quantity in Eq. (1) was calculated for each treatment of drip irrigation according to Eq. (2) (Ertek and Kanber, 2003). Ir = Epan × Kcp × P
(2)
where Ir is the amount of applied irrigation water (mm), Epan is the cumulative evaporation quantity at each irrigation interval (mm), Kcp is the plant-pan coefficient and P is the wetting area (0.60).
Evaporation quantity between irrigation intervals was measured everyday with a Class-A pan positioned near the plots. The amounts of precipitation were measured after every raining day with a pluviometer positioned near the Class-A pan. Percentage cover was taken into account for calculating the amount of irrigation water since apple trees with wide canopies were used in the study. The percentage cover was calculated as 0.60 (P) for drip irrigation treatments, while it was 1.0 (P) for flood irrigation treatment as the entire soil surface was watered then. Soil moisture was measured at respectively 30, 60, 90 and 120 cm soil depths with a digital tensiometer before each irrigation for both drip and flood irrigation treatments. Scheduled irrigations were initiated on May 20 and 21 in 2008 and 2009, respectively for drip irrigation treatments – at the time when the soil moisture capacity of the field reached 0–120 cm soil depth. Meanwhile, first irrigation for flood irrigation was initiated on June 27 and 24 in 2008 and 2009, respectively. First irrigation time was determined by taking into consideration the farmers’ common practice in the district. 2.3. Measurement of fruit quality and vegetative growth For fruit assessments, samples of 15 fruits in one tree for per replicate were selected. Total 45 fruits per treatment were assessed for quality at the commercial harvest. Physical (fruit diameter, fruit weight, fruit length, flesh firmness, skin colour) and chemical (titratable acidity and soluble solid content) analyses were conducted to determine the fruit quality (Table 2). Fifteen fruits in one tree for each plot were used for the analyses. All fruits picked during commercial harvests were graded. Fruit diameter was used as the prior quality criterion for classification. Fruit was graded on a commercial size grade ranging from 50 to 95 mm. The percentage of fruit in various size categories extra (>75 mm), class 1 (68–75 mm), class 2 (60–68 mm) and other (<60 mm) was determined. During the experiment, phenological stages (bud swelling, bud burst, full bloom, etc.) were recorded (Westwood, 1995). One-year shoots from the main branch were selected for each tree in per replications. Their numbers, lengths (cm) and diameters (mm) were measured every year in February for once in dormancy period. Shoot length and diameter were determined by digital caliper. Shoot diameters were measured from basal parts of the shoots (Köksal et al., 1999). 2.4. Experimental design and statistical analysis The experiment was designed according to completely randomized simple factorial design with tree replications. Each plot consisted of totally eight trees aligned in two rows with 5 m × 4 m tree spacing. Four trees in the middle of each plot were used for measurements. There was an extra row of trees, i.e. replications to separate the irrigation treatments from each other between the embankments. Left and right sides of the trees on the separation row received different amounts of irrigation water according to the closest irrigation treatment in order to reduce interruption between the treatments. About flood irrigation, in order to prevent the overflow of water and its impact on other plots, the perimeter of each tree in the plots was surrounded by 40 cm-high earth embankment to cover 5 m × 4 m area (between the row and in a row). Thus, separate (individual) basins for each tree were constructed. Trees were irrigated by ponding of water in the basins; separately for each tree. During each irrigation, measured amount of water was applied to equalize the missing moisture of 0–120 cm deep soil to the field capacity. So, the measures to prevent leaking of water into deep were taken. In this way, the impact of the water applied for flood irrigation on other subjects was prevented. The analysis of variance (ANOVA) test for the data was conducted with SPSS software program and differences among
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Table 1 Analysis of irrigation water. Class of irrigation water
hos (cm−1 )
Cations (mg l−1 )
pH
C2 S1
408
8.3
Anions (mg l−1 )
Na
K
Ca
Mg
CO3 −
HCO3 −
Cl−
SO4 −
7
4
44.1
46.2
–
20.2
48.6
32.5
+
+
2+
2+
Na (%)
SAR
6.9
1.04
Table 2 Quality parameters and measurements. Parameters
Unit
Measurements
Fruit weight Fruit diameter Fruit length Fruit flesh firmness
g mm mm lb
Fruit skin colour
L* a* b*
Total soluble solids content Titratable acidity
% %
Digital balance (Scaltec, SBA-51) to 0.01 g sensitivity Digital caliper was used with 0.01 mm resolution Digital caliper was used with 0.01 mm resolution Determined on two opposite sides of each fruit, using a hand held penetrometer fitted with a 11 mm diameter probe Measured on the two opposite sides of each fruit with a Minolta Chroma meter model CR-400. The data obtained were evaluated CIELAB colour scale LCD Digital bench refractometer Using a standard titration with 0.1 N sodium hydroxide and was calculated as malic acid
treatments were compared by means of Duncan multiple comparison test (SPSS, 2003).
Table 3 Total irrigation water amount (Ir ), plant water consumption (Et ), evaporation and precipitation (mm) in 2008 and 2009. Treatments
3. Results Scheduling irrigations in drip irrigation treatments were initiated on 20 May and 21 May in 2008 and 2009; the first irrigation in flood irrigation treatment was initiated on 27 June and 24 June in 2008 and 2009, respectively. Results of irrigation water amount, plant water consumption, evaporation and precipitation values are presented in Table 3.
3.1. Vegetative growth Shoot number, shoot length and shoot diameter measurements are presented in Table 4. Four days irrigation interval (I1 ) was identified to yield a higher shoot number and shoot length compared to 7-day irrigation interval (I2 ) and flood irrigation treatment.
2008
2009
Ir (mm)
Et (mm)
Ir (mm)
Et (mm)
I1 Kcp1 I1 Kcp2 I1 Kcp3 I1 Kcp4
349.2 491.9 634.6 777.2
405.6 588.1 761.5 839.6
315.1 445.3 575.5 705.8
437.2 564.2 666.5 799.6
I2 Kcp1 I2 Kcp2 I2 Kcp3 I2 Kcp4
347.7 489.7 631.6 773.6
491.9 626.2 793.2 872.0
313.6 443.0 572.5 702.2
495.7 608.8 723.4 849.9
Flood irrigation Evaporation Precipitation
997.9
1040.9
917.3
969.3 874.8 70.4
956.3 45.0
I1 = 4 days, I2 = 7 days, Kcp1 = 0.50, Kcp2 = 0.75, Kcp3 = 1.00, Kcp4 = 1.25.
Fig. 1. Et –fruit diameter (a), Et –fruit length (b) and Et –fruit weight (c) relationship.
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Table 4 Shoot number, shoot length and shoot diameter in 2008 and 2009. Treatment
Shoot number
Shoot length (cm)
Shoot diameter (mm)
2008
2009
2008
2009
2008
2009
I1 Kcp1 I1 Kcp2 I1 Kcp3 I1 Kcp4
43.7 a* 35.3 a 36.5 a 25.7 ab
50.0 ns 37.3 38.3 22.6
33.42 ab** 34.96 ab 32.06 ab 36.28 ab
59.47 abc** 67.40 a 50.72 bc 52.40 abc
4.68 bc** 5.03 abc 5.56 ab 5.03 abc
6.18 a** 6.15 a 5.48 abc 5.09 bc
I2 Kcp1 I2 Kcp2 I2 Kcp3 I2 Kcp4
34.7 a 33.7 a 33.7 a 24.3 ab
22.0 49.3 53.6 40.6
35.70 ab 35.68 ab 36.53 ab 44.51 a
46.97 bc 59.20 abc 61.80 ab 53.10 abc
5.15 abc 5.62 a 5.38 abc 5.51 abc
5.57 abc 6.17 a 5.78 ab 6.17 a
Flood irrigation
12.0 b
36.3
28.47 b
43.73 c
4.64 c
4.79 c
ns: no significant. Values with common letters do not differ significantly. I1 = 4 days, I2 = 7 days, Kcp1 = 0.50, Kcp2 = 0.75, Kcp3 = 1.00, Kcp4 = 1.25. * p < 0.05. ** p < 0.01. Table 5 Effects of irrigation treatments on some fruit parameters. Treatments
Fruit diameter (mm)
Fruit length (mm)
Fruit weight (g)
2008
2009
2008
2009
2008
2009
I1 Kcp1 I1 Kcp2 I1 Kcp3 I1 Kcp4
69.22 d* 72.83 c 77.27 a 74.78 bc
71.44 bc* 71.99 bc 75.36 a 73.76 ab
68.54 d** 73.10 bc 75.50 ab 72.54 bc
73.64 ab** 73.99 ab 75.23 ab 76.03 ab
159.75c** 189.42 b 221.41 a 194.51 b
184.21 b** 185.36 b 197.48 ab 190.69 ab
I2 Kcp1 I2 Kcp2 I2 Kcp3 I2 Kcp4
66.00 de 67.71 de 75.79 ab 73.72 bc
69.59 c 71.55 bc 74.00 ab 73.86 ab
67.45 de 69.59 cd 76.98 a 73.26 bc
68.78 c 73.91 ab 72.12 bc 77.05 a
150.84 cd 152.43 cd 217.67 a 197.24 b
151.88 c 185.75 b 188.69 b 210.07 a
Flood irrigation
66.73 e
72.10 bc
64.05 e
71.93 bc
136.69 d
183.22 b
I1 = 4 days, I2 = 7 days, Kcp1 = 0.50, Kcp2 = 0.75, Kcp3 = 1.00, Kcp4 = 1.25. Values with common letters do not differ significantly. * p < 0.05. ** p < 0.01.
No significant effects were identified on phenological stages (bud swelling, bud burst, full bloom, etc.) for either drip or flood irrigation (data not shown). 3.2. Fruit quality 3.2.1. Fruit diameter, length and weight The highest fruit diameter values were obtained from Kcp3 (1.0) treatments for both years. Kcp3 treatments showed the highest fruit length values in 2008, while the fruit length values were the highest in Kcp4 (1.25) treatments in 2009. Kcp3 treatments also indicated the highest fruit weight in the first year while I2 Kcp4 (I2 = 7 days, Kcp4 = 1.25) treatment had the highest fruit weight in the second year. It was identified that fruit diameter, length and weight values increased with increasing amounts of irrigation water in drip irrigation treatments (Table 5). The relations between plant water consumption, fruit diameter, fruit length and fruit weight are shown in Fig. 1 for drip irrigation treatments. 3.2.2. Flesh firmness and total soluble solids content Results of flesh firmness and total soluble solid measurements are presented in Table 6. Flood irrigation treatment indicated higher flesh firmness values in 2008 than those in 2009. The highest values were determined in Kcp1 (0.50) and Kcp2 (0.75) treatments of drip irrigation for both years. Kcp4 (1.25) treatments represented the lowest flesh firmness. As I2 Kcp1 (I2 = 7 days, Kcp4 = 0.50) treatment had the highest total soluble solids content (14.82%), the lowest value was obtained from I2 Kcp4 (I2 = 7 days, Kcp4 = 1.25) (12.41%) in drip irrigation in 2008. There were no statistically significant differences according to results of total soluble solids content in
2009. Flood irrigation showed one of the lowest total soluble solid content for both years. An inverse relationship was identified between flesh firmness and plant water consumption. The relationship is shown in Fig. 2. Flesh firmness values decreased as the amount of plant water consumption increased with both irrigation intervals in drip irrigation treatments during the study. Meanwhile, flesh firmness decreased as fruit diameter increased (Fig. 3). There were significant polynomial relationships for both years. Flesh firmness values of flood irrigation treatment, which were high during the first year, decreased in the second year. According to results of total soluble solids content, there is a statistically significant difference in Table 6 Effect of irrigation treatments on flesh firmness and soluble solid content of the fruit. Treatments
Flesh firmness (lb) 2008
Soluble solids content (%)
2009
2008
2009
I1 Kcp1 I1 Kcp2 I1 Kcp3 I1 Kcp4
18.53 a 18.11 ab 17.31 cd 16.93 d
17.71 a 16.84 bc 15.90 de 15.84 de
14.14 b 14.18 ab 13.27 cd 12.80 de
13.90 ns 13.63 13.03 13.71
I2 Kcp1 I2 Kcp2 I2 Kcp3 I2 Kcp4
18.70 a 18.70 a 17.99 abc 17.57 bcd
17.30 ab 17.06 abc 16.50 cd 15.59 e
14.82 a 13.77 bc 14.06 b 12.41 e
14.28 13.98 13.41 13.25
Flood irrigation
18.38 a
16.51 cd
12.79 de
13.65
**
*
**
ns: no significant. Values with common letters do not differ significantly. I1 = 4 days, I2 = 7 days, Kcp1 = 0.50, Kcp2 = 0.75, Kcp3 = 1.00, Kcp4 = 1.25. * p < 0.05. ** p < 0.01.
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Table 7 Fruit size classification under different irrigation treatments (%). Treatments
2008
2009
Extra
Class 1
Class 2
I1 Kcp1 I1 Kcp2 I1 Kcp3 I1 Kcp4
11.11 28.80 57.78 48.89
51.11 51.10 35.56 37.78
I2 Kcp1 I2 Kcp2 I2 Kcp3 I2 Kcp4
17.78 0.00 46.60 39.00 6.67
Flood irrigation
Other
Extra
Class 1
Class 2
Other
28.89 20.10 6.67 13.33
8.89 0.00 0.00 0.00
24.50 24.44 51.11 44.44
35.50 37.70 44.44 40.00
40.00 37.76 4.44 15.56
0.00 0.00 0.00 0.00
15.56 53.33 35.50 40.22
55.56 46.67 17.90 20.78
11.11 0.00 0.00 0.00
17.78 24.40 42.22 37.70
42.22 42.20 42.22 42.20
37.78 33.40 15.56 20.10
2.22 0.00 0.00 0.00
22.22
64.44
6.67
26.60
35.50
37.90
0.00
Extra (>75 mm), class 1 (68–75 mm), class 2 (60–68 mm), other (<60 mm). I1 = 4 days, I2 = 7 days, Kcp1 = 0.50, Kcp2 = 0.75, Kcp3 = 1.00, Kcp4 = 1.25.
Fig. 2. Plant water consumption–flesh firmness relationship.
the first year (p < 0.05), but not in the second year. Flood irrigation treatment indicated lower total soluble solids values for both years. 3.2.3. Fruit size classification According to fruit size classification, the sum of extra and class 1 fruit ratio increased as the pan coefficient increased, but it decreased after Kcp3 (1.0) pan coefficient for both irrigation intervals in drip irrigation (Table 7). The highest extra and class 1 fruit ratios were obtained with Kcp3 = 1.0 treatments for both irrigation intervals during the study. The highest ratio of class 2 fruits was noted with flood irrigation treatment in the first year, while Kcp1 and flood irrigation treatments indicated the lowest values in the second year. Significant differences in fruit background colour occurred among all treatments (Table 8). “L” (fruit flesh brightness) values decreased down to Kcp3 = 1.0, but they bounced after that level. While “a” (red colour density) values increased up to Kcp3 = 1.0 level as the amount of irrigation water increased; they decreased
after that level (Kcp3 = 1.0) with drip irrigation treatment for both years. The correlation equations in Table 9 elucidate the relationships between the plant’s water consumption (Et ) and the fruit diameter (Fruit diameter), fruit length (Fruit length), fruit weight (Fruit weight) and fruit flesh firmness (Fruit flesh firmness). Similarly, the relationship between the fruit diameter (Fruit diameter) and fruit flesh firmness (Fruit flesh firmness) was also observed. Accordingly, a polynomial relationship was determined between the plant’s water consumption and fruit diameter in both years at 5% level. That is, the fruit size increased by a certain extent as the plant’s water consumption increased. However, fruit diameter values began to decrease after Kcp3 (1.0) level. In other words, the highest fruit diameter values were noted at Kcp3 (1.0) level. A 5% level of polynomial relationship and a 5% level linear relationship were observed between the plant’s water consumption and the fruit length respectively in the first and the second year. A polynomial relationship at 5% level was also determined between the plant’s water consumption and fruit weight in both years. Here also the fruit weight values increased up to Kcp3 (1.0) and began to decrease afterwards. These relationships are shown on a graph in Fig. 1. A significant inverse linear relationship was identified between the plant’s water consumption and fruit flesh firmness in both years at 1% level (Fig. 2). That is, the fruit flesh firmness values decreased as the plant’s water consumption increased. As shown in Fig. 3, a significant inverse linear relationship was also determined between the fruit diameter and fruit flesh firmness.
Table 8 Skin colour as per irrigation treatments. Treatments
2008
2009
L
Fig. 3. Fruit diameter–flesh firmness relationship.
a
L
a
I1 Kcp1 I1 Kcp2 I1 Kcp3 I1 Kcp4
48.98 ab 47.63 ab 44.70 de 46.86 bcd
22.96 bc 23.52 bc 27.31 a 23.36 bc
42.25 a 41.02 ab 40.30 ab 41.29 a
25.50 d** 26.61 cd 29.75 a 26.56 cd
I2 Kcp1 I2 Kcp2 I2 Kcp3 I2 Kcp4
49.53 a 47.79 ab 43.27 e 44.92 cde
22.09 c 23.69 bc 26.41 ab 24.42 abc
41.71 a 42.05 a 40.36 ab 41.09 ab
26.99 bcd 27.12 bcd 28.18 abc 26.58 cd
Flood irrigation
47.10 bc
22.71 c
39.29 b
28.68 ab
*
**
*
I1 = 4 days, I2 = 7 days, Kcp1 = 0.50, Kcp2 = 0.75, Kcp3 = 1.00, Kcp4 = 1.25. Values with common letters do not differ significantly. * p < 0.05. ** p < 0.01.
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Table 9 Correlation equations and coefficients among the examined plant components. Yield components Evapotranspiration (Et ) Fruit diameter Fruit length Fruit weight Fruit flesh firmness Fruit diameter Fruit flesh firmness * **
2008
2009
y = −2E−05x2 + 0.038x + 57.66 R2 = 0.59* y = −5E−05x2 + 0.074x + 44.41 R2 = 0.60* y = 8E−05x2 − 0.027x + 168.4 R2 = 0.49* y = −0.003x + 20.13 R2 = 0.72**
y = −1E−05x2 + 0.032x + 56.16 R2 = 0.56* y = 0.012x + 65.55 R2 = 0.53* y = −0.000x2 + 0.379x + 26.71 R2 = 0.54* y = −0.004x + 19.76 R2 = 0.87**
y = −0.145x + 28.50 R2 = 0.72**
y = −0.339x + 41.23 R2 = 0.68**
p < 0.05. p < 0.01.
4. Discussion 4.1. Vegetative growth According to the results of vegetative growth measurements, differences were determined among all treatments, but a clear relationship could not be identified. It is clear that transition from flood irrigation to drip irrigation method has positive effects on vegetative growth of apple trees. Plants spend most of their energies while taking water from the soil by their roots (Kocac¸alıs¸kan, 2005). Because the irrigation interval is long during flood irrigation, and the soil’s water decreases continuously after irrigation; roots of trees spend most of their energies during water intake, and spend less energy for growth and development. In drip irrigation, as the soil is more humid due to frequent irrigation interval, the trees do not spend much energy while taking water from the soil. They spend most of their energies for growth, development, productivity and fruit quality. Therefore the vegetative growth of drip irrigation treatments was positively influenced. Examination of shoot diameter, shoot length and shoot number figures of both years suggests an increase during drip irrigation treatments compared to those of flood irrigation. The reason of the increase in these values is the positive impact on vegetative growth. Similarly, Safran et al. (1975) pointed that fruit trees which had been irrigated for many years with surface irrigation methods did not indicate any reduction in vegetative growth after switching to drip irrigation, and drip irrigation had a positive effect on vegetative growth. Some researchers reported that different irrigation schedules on plum and pistachio trees and different irrigation methods on lemon trees had no effects on vegetative growth (Yıldırım and Yıldırım, 2005; Bilgel et al., 1999; C¸evik et al., 1993). 4.2. Fruit quality Positive effects of transition from flood irrigation to drip irrigation method were identified on fruit quality. Different irrigation programmes had different effects on fruit quality with drip irrigation during the study. Fruit diameter values increased as the pan coefficient increased but they decreased after Kcp3 (1.0) pan coefficient for both irrigation intervals. The lowest fruit diameter was obtained from the treatments with the lowest water (Kcp1 = 0.50) in drip irrigation (Table 5). The results of this study support the conclusions of Lord et al. (1963) and Landsberg and Jones (1981). Bergamini et al. (1990) reported for Golden Delicious apple variety that fruit diameter increased as the irrigation water amount in drip irrigation method increased. C¸ay et al. (2009) identified the highest fruit diameter in Kcp = 1.0 treatments for apple trees with drip irrigation method. Although fruit length values also increased
up to a certain level (Kcp3 = 1.0), they later decreased from that level (Kcp3 = 1.0) during the first year of the study. Nonetheless, an increase in fruit length values was identified with increased pan coefficient (Kcp ) in the second year. As expected, fruit diameter, length and fruit weight were lower in flood irrigation than drip irrigation treatments. With regard to fruit weight, the figures indicated an increase in the first year, up to (Kcp3 = 1.0), but a decrease was observed after that level (Kcp3 = 1.0). As similar curves were also noted in I1 treatments (4 days irrigation interval) during the second year; fruit weight values increased with increasing pan coefficients (Kcp ) in I2 treatments (7 days irrigation interval) (Table 5). An overall decline was observed for all values (fruit diameter, weight and length) as the irrigation intervals increased. Fruit diameter, length and weight values obtained from flood irrigation treatment were generally lower than those obtained from drip irrigation treatments. Flood irrigation treatment represented lower fruit quality figures. Different irrigation methods have different effects on fruit quality. Köksal et al. (1999) obtained the highest fruit diameter from drip irrigation method. Therefore, it is possible to say that drip irrigation method has more positive effects than flood irrigation method. Flesh firmness values decreased as the amount of irrigation water increased for both irrigation intervals of drip irrigation treatments during the study. The amount of irrigation water was noted as critical for fruit flesh firmness. Bonany and Camps (1998) already stated that flesh firmness of apples decreased as the amount of irrigation water increased. In general, total soluble solids values decreased as the amount of irrigation water increased. This result supports the findings of Morris et al. (1962) and Drake et al. (1981) who reported that the figures of total soluble solids content were higher for less irrigated fruits than excessively irrigated fruits. Flood irrigation treatment showed low soluble solid values for both years. The highest extra and class 1 fruit ratios were identified with drip irrigation treatments during the study. Flood irrigation treatment showed the lowest values. It has been identified that transition from flood irrigation method to drip irrigation increases the fruit size, which is an important marketing criterion for apple growing. Besides, obtaining the highest fruit diameter will be possible when Kcp3 (1.0) pan coefficient is used. Increased extra fruit ratio with drip irrigation was also observed by Köksal et al. (1999). An inverse ratio was identified between red colour density and fruit flesh brightness values during the study. An increase in red colour density (a) was identified as the fruit flesh brightness (L) decreased. Increasing irrigation water amounts affected red colour density in both irrigation intervals positively, but red colour density decreased after Kcp3 = 1.0 level. The highest red colour density figures were noted in Kcp3 = 1.0 treatments of drip irrigation.
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5. Conclusion According to the results of the study, it is concluded that transition from flood irrigation to drip irrigation method have positive effects on vegetative growth and fruit quality of apple trees which had previously been irrigated by flood irrigation for many years. An increase in fruit quality (marketable fruit diameter, fruit length, fruit weight, fruit skin colour) has been noted with drip irrigation method. The highest marketable fruit diameter was observed with Kcp3 (1.0) and Kcp4 (1.25) treatments. However, Kcp3 treatments are more preferable as they consume less irrigation water, thus result in saving water. To obtain a high quantity of marketable apples, Kcp treatment with 1.0 and irrigation interval with 4 days are recommended during transition from flood irrigation to drip irrigation for similar climatic and soil conditions. Apple growers should be encouraged to employ drip irrigation method instead of flood irrigation for a higher fruit quality and lower irrigation water consumption. Acknowledgement This study was summarized partially from the research project supported by the General Directorate of Agricultural Research and Policy, Food, Agriculture and Livestock Ministry, Turkey. References Anonymous, 2011a. Food and Agriculture Organization of the United Nations (FAOSTAT)., http://faostat.fao.org/site/291/default.aspx. Anonymous, 2011b. Turkey Republic, Institute of Statistics Prime Ministry, Ankara (official data). Bergamini, A., Angelini, S. and Bigaran, F., 1990. Influence of 4 different rootstocks on the stomal resistance and leaf water potential of Golden Delicious Clone B (Virus T Ree) Subjected to Different Irrigation Regimes. Societa Orticola Italiana, 1988, pp. 533–544 (Hort. Abstr. 60, 2256). Bilgel, L., Da˘gdeviren, I˙ ., Nacar, A.S., 1999. Determining irrigation scheduling and plant water consumption of Pistachio (Siirt variety) in GAP region Harran plain. In: Türkiye III. National Horticultural Congress, Ankara, pp. 252–257.
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Bonany, J., Camps, F., 1998. Effects of different irrigation levels on apple fruit quality. Acta Horticulturae (ISHS) 466, 47–52. C¸ay, S¸., Tarı, A.F., Dinc¸, N., Bitgi, S., Özbahc¸e, A., Palta, C¸., Okur, O., 2009. Effects of different irrigation programmes on yield and quality characteristics of Granny Smith apple variety grafted onto M9 rootstock. Journal of Agriculture Sciences Researches 2 (2), 73–79. C¸evik, B., Tuzcu, Ö., Kaplankıran, M., Yurdakul, O., Tekinel, O., Korkmaz, S., 1993. A study on determining the most suitable irrigation program for lemon trees in C¸ukurova plain. Turkish Journal of Agricultural and Forestry 17, 471–486. Drake., S.R., Proebsting, E.L., Mahan Jr., M.O., Thompson, J.B., 1981. Influence of trickle and sprinkle irrigation on Golden Delicious apple quality. Journal of American Society Horticulture Science 106 (3), 255–258. Ertek, A., Kanber, R., 2003. Effects of different irrigation programs on boll number and abscission percentage of cotton. Agricultural Water Management 60 (1), 1–11. James, L.G., 1988. Principles of Farm Irrigation System Design. John Wiley and Sons, Inc., New York, USA, p. 543. Kocac¸alıs¸kan, I˙ ., 2005. Plant Physiology. Dumlupınar University Faculty of Arts and Science, Department of Biology, Kütahya, 420 pp. Köksal, A.I˙ ., Dumano˘glu, H., Günes¸, N., Yıldırım, O., Kadayıfc¸ı, A., 1999. Effects of different irrigation methods and regimes on vegetative growth, fruit yield and quality of apple trees. Turkish Journal of Agriculture and Forestry 23, 909–920 (Additional press: 4). Landsberg, J.J., Jones, H.G., 1981. Apple orchards. In: Kozlowski, T.T. (Ed.), Water Deficits and Plant Growth, vol. VI. Academic Press, New York, pp. 419–469. Lord, W.J., Michelson, L.F., Field, D.L., 1963. Response to Irrigation and Soil Moisture Use by Mcintosh Apple Trees in Masachusetts. Experiment Station Publication, MA, p. 537. Morris, J.R., Kattan, A.A., Arrington, E.H., 1962. Response of Elberta peaches to the interactive effects of irrigation, pruning and thinning. Proceedings of the American Society for Horticulture Science 80, 177L 189. Önder, S., Kanber, R., Önder, D., Kapur, B., 2005. The differences of possibility of global climate changing on irrigation methods and management techniques. In: GAP IV. Congress of Agriculture, 21–23 September, pp. 1128–1135, S¸ANLIURFA. Safran, B., Bravdo, B., Bernstein, Z., 1975. L’irrigation de la vigue par goutte a gutte. Bulletin de l’OIV 48, 406–429. SPSS, 2003. SPSS 12.0 Copyright, SPSS Inc. USSL, 1954. Diagnosis and improvement of saline and alkali soils. Agriculture Handbook No. 60. USDA. Westwood, M.N., 1995. Temperate-zone Pomology, Physiology and Culture, third ed. Timber Press, Portland, Oregon, ISBN 0-8819-2253-6, 523 pp. Yıldırım, M., Yıldırım, O., 2005. The effects of different irrigation programmes on plum yield and tree growth in drip irrigation method. Uluda˘g University Journal of Agriculture Faculty 19 (1), 37–49.
Contents lists available at SciVerse ScienceDirect
Scientia Horticulturae journal homepage: www.elsevier.com/locate/scihorti
Pomological and vegetative changes during transition from flood irrigation to drip irrigation: Starkrimson Delicious apple variety Cenk Küc¸ükyumuk a,∗ , Emel Kac¸al a , Ahmet Ertek b , Gökhan Öztürk a , Yasemin S. Kukul Kurttas¸ c a
E˘girdir Fruit Growing Research Station, 32500 Isparta, Turkey Süleyman Demirel University, Faculty of Agriculture, Department of Agricultural Structures and Irrigation, Isparta, Turkey c Ege University, Faculty of Agriculture, Department of Agricultural Structures and Irrigation, 35100 I˙ zmir, Turkey b
a r t i c l e
i n f o
Article history: Received 5 September 2011 Received in revised form 4 December 2011 Accepted 8 December 2011 Keywords: Apple Drip irrigation Flood irrigation Fruit quality Vegetative growth
a b s t r a c t Considering that apple growers have commonly used flood irrigation method instead of drip irrigation for many decades, this study aims to determine the effects of transition from flood irrigation to drip irrigation on vegetative growth and fruit quality (fruit diameter, length, weight, colour, firmness and classification). An apple orchard which had been irrigated by flood irrigation for many years was used for the study, during which flood irrigation was continued in one section as a control treatment, while drip irrigation was applied for rest of the apple orchard. Two different irrigation intervals (4 and 7 days) and four different pan coefficients (0.50, 0.75, 1.0, 1.25) were applied during drip irrigation treatments. Flood irrigation included only one treatment (20 days irrigation interval). Transition to drip irrigation method for apple trees indicated positive consequences on vegetative growth and fruit quality. Fruit diameter, length and weight values were the highest in Kcp3 (1.0) treatments in drip irrigation. Kcp3 treatments also showed the highest red colour density values. Kcp3 and Kcp4 (1.25) represented a more marketable fruit size (extra and class 1) than flood irrigation. Lower amount of irrigation water was consumed with drip irrigation compared to flood irrigation. To obtain the highest quantity of marketable apples, Kcp treatment with 1.0 and irrigation interval with 4 days (I1 Kcp3 treatment) is recommended during transition from flood irrigation to drip irrigation for similar climatic and soil conditions. © 2011 Elsevier B.V. All rights reserved.
1. Introduction Water is consumed plentifully for agricultural purposes in Turkey and in the World (approximately 70%). Nevertheless, the rate of water consumption for industrial and domestic needs is gradually increasing and the rate of water consumption for agricultural irrigation is decreasing (Önder et al., 2005) that necessitate a more efficient use of available water resources. Consequently, irrigation methods with a contribution on saving water (drip irrigation method, etc.) should be used more. Surface irrigation methods (flood irrigation, etc.) have been used extensively in fruit growing, and transition to drip irrigation method has started being preferred more in recent years. Because drip irrigation method offers certain advantages such as fruit quality, decreasing labour costs, saving irrigation water, etc., many fruit growers have adopted this method. The adoption of drip irrigation method has expanded further especially at the regions with limited water resources. However, fruit growers who began to
∗ Corresponding author. Tel.: +90 246 3132420; fax: +90 246 3132425. E-mail address: [email protected] (C. Küc¸ükyumuk). 0304-4238/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.scienta.2011.12.012
employ drip irrigation reported decreasing fruit quality, weak vegetative growth and lower yield. Therefore, the effects of changing the irrigation method on fruit quality, vegetative growth and yield should be examined and an irrigation schedule should be designed. Apple is one of the most important fruits produced in Turkey. Apple production in Turkey is estimated as 3.9% of the world apple production (Anonymous, 2011a). Isparta, Karaman, Ni˘gde, Antalya and Denizli are the leading apple growing areas. Isparta is a very important apple growing region of Turkey with a production accounting for nearly 22% of the country’s total (Anonymous, 2011b). Apple growers have certain problems about growing techniques, especially irrigation. Drip irrigation method has been preferred for irrigating apple orchards in recent years. Albeit, some growers have continued employing flood irrigation as they think that transition to drip irrigation has negative effects on fruit quality and vegetative growth. This study identifies the effects of transition from flood irrigation method to drip irrigation on fruit quality and vegetative growth. At the same time, the study also aims to determine the most suitable irrigation scheduling for high fruit quality and vegetative growth in drip irrigation method.
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2. Materials and methods 2.1. Study area and plant material This study was carried out in E˘girdir Fruit Growing Research Station (37◦ 49 17.97 N, 30◦ 52 22.44 E), Isparta, Turkey during 2008 and 2009 growing seasons. The research area has a transition climate between the Mediterranean and Central Anatolia. The orchard soil was clay loam. Apple trees were planted in 1988 (5 m × 4 m spacing) and Starkrimson Delicious variety grafted onto seedling rootstock was used in the study. 2.2. Irrigation treatments The orchard had been irrigated by flood irrigation method until the beginning of this study (2008). During the study, flood irrigation treatment was considered as a control treatment in order to determine the effects of changing the irrigation method on fruit quality and vegetative growth of apple trees. Flood irrigation treatment was a part of the orchard and different irrigation programmes in drip irrigation were applied on the rest of the orchard. Two different irrigation intervals (I1 = 4 days, I2 = 7 days) and four different pan coefficients (Kcp1 = 0.50, Kcp2 = 0.75, Kcp3 = 1.00, Kcp4 = 1.25) were used for drip irrigation treatments. Only one irrigation interval (20 days) was used for flood irrigation treatment because apple growers commonly use 20 days as irrigation interval in the district. The results of the analysis of the irrigation water used in the study are given in Table 1. Classification was realized according to the US Salinity Laboratory Graphical System. According to this system, the salinity values of the irrigation water, which are in 250–750 EC × 106 range, are included in category C2 , and in category S1 in terms of SAR value (USSL, 1954). Irrigation water was C2 S1 class, which is suitable for irrigation. Irrigation water was supplied from an irrigation canal by a pump. The lateral pipes having 16 mm diameter were laid down on both sides of each row of trees. Emitter spacing on lateral sides was 0.75 m with all emitters having a discharge rate of 4 l h−1 . The plots in flood irrigation treatment were embanked in order to prevent water overflow. Irrigation quantities were based on pan evaporation (Epan ) from class-A pan for drip irrigation treatments. Evapotranspiration was calculated according to the following water balance method (Eq. (1)) (James, 1988) for each treatment of drip irrigation. The moisture of soil was measured before each irrigation and the applied irrigation water amount during each irrigation was noted. During the next irrigation, the soil moisture was measured and the difference was recorded as “plant water consumption” of that treatment. Et = Ir + R + Cr − Dp − Rf ± s
(1)
where Et is the evapotranspiration (mm), Ir is the amount of irrigation water (mm), R is the rainfall (mm), Cr is the capillary rise (mm), Dp is the water loss by deep percolation (mm), Rf is the surface run-off (mm), and s is the change in profile soil water content (mm). Cr values were considered as zero as there were no ground water problems in the area. Dp was ignored since the amount of water applied through irrigation was not above the field capacity. Rf was not taken into account either as the total water amount applied through irrigation was measured for each irrigation. Irrigation quantity in Eq. (1) was calculated for each treatment of drip irrigation according to Eq. (2) (Ertek and Kanber, 2003). Ir = Epan × Kcp × P
(2)
where Ir is the amount of applied irrigation water (mm), Epan is the cumulative evaporation quantity at each irrigation interval (mm), Kcp is the plant-pan coefficient and P is the wetting area (0.60).
Evaporation quantity between irrigation intervals was measured everyday with a Class-A pan positioned near the plots. The amounts of precipitation were measured after every raining day with a pluviometer positioned near the Class-A pan. Percentage cover was taken into account for calculating the amount of irrigation water since apple trees with wide canopies were used in the study. The percentage cover was calculated as 0.60 (P) for drip irrigation treatments, while it was 1.0 (P) for flood irrigation treatment as the entire soil surface was watered then. Soil moisture was measured at respectively 30, 60, 90 and 120 cm soil depths with a digital tensiometer before each irrigation for both drip and flood irrigation treatments. Scheduled irrigations were initiated on May 20 and 21 in 2008 and 2009, respectively for drip irrigation treatments – at the time when the soil moisture capacity of the field reached 0–120 cm soil depth. Meanwhile, first irrigation for flood irrigation was initiated on June 27 and 24 in 2008 and 2009, respectively. First irrigation time was determined by taking into consideration the farmers’ common practice in the district. 2.3. Measurement of fruit quality and vegetative growth For fruit assessments, samples of 15 fruits in one tree for per replicate were selected. Total 45 fruits per treatment were assessed for quality at the commercial harvest. Physical (fruit diameter, fruit weight, fruit length, flesh firmness, skin colour) and chemical (titratable acidity and soluble solid content) analyses were conducted to determine the fruit quality (Table 2). Fifteen fruits in one tree for each plot were used for the analyses. All fruits picked during commercial harvests were graded. Fruit diameter was used as the prior quality criterion for classification. Fruit was graded on a commercial size grade ranging from 50 to 95 mm. The percentage of fruit in various size categories extra (>75 mm), class 1 (68–75 mm), class 2 (60–68 mm) and other (<60 mm) was determined. During the experiment, phenological stages (bud swelling, bud burst, full bloom, etc.) were recorded (Westwood, 1995). One-year shoots from the main branch were selected for each tree in per replications. Their numbers, lengths (cm) and diameters (mm) were measured every year in February for once in dormancy period. Shoot length and diameter were determined by digital caliper. Shoot diameters were measured from basal parts of the shoots (Köksal et al., 1999). 2.4. Experimental design and statistical analysis The experiment was designed according to completely randomized simple factorial design with tree replications. Each plot consisted of totally eight trees aligned in two rows with 5 m × 4 m tree spacing. Four trees in the middle of each plot were used for measurements. There was an extra row of trees, i.e. replications to separate the irrigation treatments from each other between the embankments. Left and right sides of the trees on the separation row received different amounts of irrigation water according to the closest irrigation treatment in order to reduce interruption between the treatments. About flood irrigation, in order to prevent the overflow of water and its impact on other plots, the perimeter of each tree in the plots was surrounded by 40 cm-high earth embankment to cover 5 m × 4 m area (between the row and in a row). Thus, separate (individual) basins for each tree were constructed. Trees were irrigated by ponding of water in the basins; separately for each tree. During each irrigation, measured amount of water was applied to equalize the missing moisture of 0–120 cm deep soil to the field capacity. So, the measures to prevent leaking of water into deep were taken. In this way, the impact of the water applied for flood irrigation on other subjects was prevented. The analysis of variance (ANOVA) test for the data was conducted with SPSS software program and differences among
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Table 1 Analysis of irrigation water. Class of irrigation water
hos (cm−1 )
Cations (mg l−1 )
pH
C2 S1
408
8.3
Anions (mg l−1 )
Na
K
Ca
Mg
CO3 −
HCO3 −
Cl−
SO4 −
7
4
44.1
46.2
–
20.2
48.6
32.5
+
+
2+
2+
Na (%)
SAR
6.9
1.04
Table 2 Quality parameters and measurements. Parameters
Unit
Measurements
Fruit weight Fruit diameter Fruit length Fruit flesh firmness
g mm mm lb
Fruit skin colour
L* a* b*
Total soluble solids content Titratable acidity
% %
Digital balance (Scaltec, SBA-51) to 0.01 g sensitivity Digital caliper was used with 0.01 mm resolution Digital caliper was used with 0.01 mm resolution Determined on two opposite sides of each fruit, using a hand held penetrometer fitted with a 11 mm diameter probe Measured on the two opposite sides of each fruit with a Minolta Chroma meter model CR-400. The data obtained were evaluated CIELAB colour scale LCD Digital bench refractometer Using a standard titration with 0.1 N sodium hydroxide and was calculated as malic acid
treatments were compared by means of Duncan multiple comparison test (SPSS, 2003).
Table 3 Total irrigation water amount (Ir ), plant water consumption (Et ), evaporation and precipitation (mm) in 2008 and 2009. Treatments
3. Results Scheduling irrigations in drip irrigation treatments were initiated on 20 May and 21 May in 2008 and 2009; the first irrigation in flood irrigation treatment was initiated on 27 June and 24 June in 2008 and 2009, respectively. Results of irrigation water amount, plant water consumption, evaporation and precipitation values are presented in Table 3.
3.1. Vegetative growth Shoot number, shoot length and shoot diameter measurements are presented in Table 4. Four days irrigation interval (I1 ) was identified to yield a higher shoot number and shoot length compared to 7-day irrigation interval (I2 ) and flood irrigation treatment.
2008
2009
Ir (mm)
Et (mm)
Ir (mm)
Et (mm)
I1 Kcp1 I1 Kcp2 I1 Kcp3 I1 Kcp4
349.2 491.9 634.6 777.2
405.6 588.1 761.5 839.6
315.1 445.3 575.5 705.8
437.2 564.2 666.5 799.6
I2 Kcp1 I2 Kcp2 I2 Kcp3 I2 Kcp4
347.7 489.7 631.6 773.6
491.9 626.2 793.2 872.0
313.6 443.0 572.5 702.2
495.7 608.8 723.4 849.9
Flood irrigation Evaporation Precipitation
997.9
1040.9
917.3
969.3 874.8 70.4
956.3 45.0
I1 = 4 days, I2 = 7 days, Kcp1 = 0.50, Kcp2 = 0.75, Kcp3 = 1.00, Kcp4 = 1.25.
Fig. 1. Et –fruit diameter (a), Et –fruit length (b) and Et –fruit weight (c) relationship.
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Table 4 Shoot number, shoot length and shoot diameter in 2008 and 2009. Treatment
Shoot number
Shoot length (cm)
Shoot diameter (mm)
2008
2009
2008
2009
2008
2009
I1 Kcp1 I1 Kcp2 I1 Kcp3 I1 Kcp4
43.7 a* 35.3 a 36.5 a 25.7 ab
50.0 ns 37.3 38.3 22.6
33.42 ab** 34.96 ab 32.06 ab 36.28 ab
59.47 abc** 67.40 a 50.72 bc 52.40 abc
4.68 bc** 5.03 abc 5.56 ab 5.03 abc
6.18 a** 6.15 a 5.48 abc 5.09 bc
I2 Kcp1 I2 Kcp2 I2 Kcp3 I2 Kcp4
34.7 a 33.7 a 33.7 a 24.3 ab
22.0 49.3 53.6 40.6
35.70 ab 35.68 ab 36.53 ab 44.51 a
46.97 bc 59.20 abc 61.80 ab 53.10 abc
5.15 abc 5.62 a 5.38 abc 5.51 abc
5.57 abc 6.17 a 5.78 ab 6.17 a
Flood irrigation
12.0 b
36.3
28.47 b
43.73 c
4.64 c
4.79 c
ns: no significant. Values with common letters do not differ significantly. I1 = 4 days, I2 = 7 days, Kcp1 = 0.50, Kcp2 = 0.75, Kcp3 = 1.00, Kcp4 = 1.25. * p < 0.05. ** p < 0.01. Table 5 Effects of irrigation treatments on some fruit parameters. Treatments
Fruit diameter (mm)
Fruit length (mm)
Fruit weight (g)
2008
2009
2008
2009
2008
2009
I1 Kcp1 I1 Kcp2 I1 Kcp3 I1 Kcp4
69.22 d* 72.83 c 77.27 a 74.78 bc
71.44 bc* 71.99 bc 75.36 a 73.76 ab
68.54 d** 73.10 bc 75.50 ab 72.54 bc
73.64 ab** 73.99 ab 75.23 ab 76.03 ab
159.75c** 189.42 b 221.41 a 194.51 b
184.21 b** 185.36 b 197.48 ab 190.69 ab
I2 Kcp1 I2 Kcp2 I2 Kcp3 I2 Kcp4
66.00 de 67.71 de 75.79 ab 73.72 bc
69.59 c 71.55 bc 74.00 ab 73.86 ab
67.45 de 69.59 cd 76.98 a 73.26 bc
68.78 c 73.91 ab 72.12 bc 77.05 a
150.84 cd 152.43 cd 217.67 a 197.24 b
151.88 c 185.75 b 188.69 b 210.07 a
Flood irrigation
66.73 e
72.10 bc
64.05 e
71.93 bc
136.69 d
183.22 b
I1 = 4 days, I2 = 7 days, Kcp1 = 0.50, Kcp2 = 0.75, Kcp3 = 1.00, Kcp4 = 1.25. Values with common letters do not differ significantly. * p < 0.05. ** p < 0.01.
No significant effects were identified on phenological stages (bud swelling, bud burst, full bloom, etc.) for either drip or flood irrigation (data not shown). 3.2. Fruit quality 3.2.1. Fruit diameter, length and weight The highest fruit diameter values were obtained from Kcp3 (1.0) treatments for both years. Kcp3 treatments showed the highest fruit length values in 2008, while the fruit length values were the highest in Kcp4 (1.25) treatments in 2009. Kcp3 treatments also indicated the highest fruit weight in the first year while I2 Kcp4 (I2 = 7 days, Kcp4 = 1.25) treatment had the highest fruit weight in the second year. It was identified that fruit diameter, length and weight values increased with increasing amounts of irrigation water in drip irrigation treatments (Table 5). The relations between plant water consumption, fruit diameter, fruit length and fruit weight are shown in Fig. 1 for drip irrigation treatments. 3.2.2. Flesh firmness and total soluble solids content Results of flesh firmness and total soluble solid measurements are presented in Table 6. Flood irrigation treatment indicated higher flesh firmness values in 2008 than those in 2009. The highest values were determined in Kcp1 (0.50) and Kcp2 (0.75) treatments of drip irrigation for both years. Kcp4 (1.25) treatments represented the lowest flesh firmness. As I2 Kcp1 (I2 = 7 days, Kcp4 = 0.50) treatment had the highest total soluble solids content (14.82%), the lowest value was obtained from I2 Kcp4 (I2 = 7 days, Kcp4 = 1.25) (12.41%) in drip irrigation in 2008. There were no statistically significant differences according to results of total soluble solids content in
2009. Flood irrigation showed one of the lowest total soluble solid content for both years. An inverse relationship was identified between flesh firmness and plant water consumption. The relationship is shown in Fig. 2. Flesh firmness values decreased as the amount of plant water consumption increased with both irrigation intervals in drip irrigation treatments during the study. Meanwhile, flesh firmness decreased as fruit diameter increased (Fig. 3). There were significant polynomial relationships for both years. Flesh firmness values of flood irrigation treatment, which were high during the first year, decreased in the second year. According to results of total soluble solids content, there is a statistically significant difference in Table 6 Effect of irrigation treatments on flesh firmness and soluble solid content of the fruit. Treatments
Flesh firmness (lb) 2008
Soluble solids content (%)
2009
2008
2009
I1 Kcp1 I1 Kcp2 I1 Kcp3 I1 Kcp4
18.53 a 18.11 ab 17.31 cd 16.93 d
17.71 a 16.84 bc 15.90 de 15.84 de
14.14 b 14.18 ab 13.27 cd 12.80 de
13.90 ns 13.63 13.03 13.71
I2 Kcp1 I2 Kcp2 I2 Kcp3 I2 Kcp4
18.70 a 18.70 a 17.99 abc 17.57 bcd
17.30 ab 17.06 abc 16.50 cd 15.59 e
14.82 a 13.77 bc 14.06 b 12.41 e
14.28 13.98 13.41 13.25
Flood irrigation
18.38 a
16.51 cd
12.79 de
13.65
**
*
**
ns: no significant. Values with common letters do not differ significantly. I1 = 4 days, I2 = 7 days, Kcp1 = 0.50, Kcp2 = 0.75, Kcp3 = 1.00, Kcp4 = 1.25. * p < 0.05. ** p < 0.01.
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Table 7 Fruit size classification under different irrigation treatments (%). Treatments
2008
2009
Extra
Class 1
Class 2
I1 Kcp1 I1 Kcp2 I1 Kcp3 I1 Kcp4
11.11 28.80 57.78 48.89
51.11 51.10 35.56 37.78
I2 Kcp1 I2 Kcp2 I2 Kcp3 I2 Kcp4
17.78 0.00 46.60 39.00 6.67
Flood irrigation
Other
Extra
Class 1
Class 2
Other
28.89 20.10 6.67 13.33
8.89 0.00 0.00 0.00
24.50 24.44 51.11 44.44
35.50 37.70 44.44 40.00
40.00 37.76 4.44 15.56
0.00 0.00 0.00 0.00
15.56 53.33 35.50 40.22
55.56 46.67 17.90 20.78
11.11 0.00 0.00 0.00
17.78 24.40 42.22 37.70
42.22 42.20 42.22 42.20
37.78 33.40 15.56 20.10
2.22 0.00 0.00 0.00
22.22
64.44
6.67
26.60
35.50
37.90
0.00
Extra (>75 mm), class 1 (68–75 mm), class 2 (60–68 mm), other (<60 mm). I1 = 4 days, I2 = 7 days, Kcp1 = 0.50, Kcp2 = 0.75, Kcp3 = 1.00, Kcp4 = 1.25.
Fig. 2. Plant water consumption–flesh firmness relationship.
the first year (p < 0.05), but not in the second year. Flood irrigation treatment indicated lower total soluble solids values for both years. 3.2.3. Fruit size classification According to fruit size classification, the sum of extra and class 1 fruit ratio increased as the pan coefficient increased, but it decreased after Kcp3 (1.0) pan coefficient for both irrigation intervals in drip irrigation (Table 7). The highest extra and class 1 fruit ratios were obtained with Kcp3 = 1.0 treatments for both irrigation intervals during the study. The highest ratio of class 2 fruits was noted with flood irrigation treatment in the first year, while Kcp1 and flood irrigation treatments indicated the lowest values in the second year. Significant differences in fruit background colour occurred among all treatments (Table 8). “L” (fruit flesh brightness) values decreased down to Kcp3 = 1.0, but they bounced after that level. While “a” (red colour density) values increased up to Kcp3 = 1.0 level as the amount of irrigation water increased; they decreased
after that level (Kcp3 = 1.0) with drip irrigation treatment for both years. The correlation equations in Table 9 elucidate the relationships between the plant’s water consumption (Et ) and the fruit diameter (Fruit diameter), fruit length (Fruit length), fruit weight (Fruit weight) and fruit flesh firmness (Fruit flesh firmness). Similarly, the relationship between the fruit diameter (Fruit diameter) and fruit flesh firmness (Fruit flesh firmness) was also observed. Accordingly, a polynomial relationship was determined between the plant’s water consumption and fruit diameter in both years at 5% level. That is, the fruit size increased by a certain extent as the plant’s water consumption increased. However, fruit diameter values began to decrease after Kcp3 (1.0) level. In other words, the highest fruit diameter values were noted at Kcp3 (1.0) level. A 5% level of polynomial relationship and a 5% level linear relationship were observed between the plant’s water consumption and the fruit length respectively in the first and the second year. A polynomial relationship at 5% level was also determined between the plant’s water consumption and fruit weight in both years. Here also the fruit weight values increased up to Kcp3 (1.0) and began to decrease afterwards. These relationships are shown on a graph in Fig. 1. A significant inverse linear relationship was identified between the plant’s water consumption and fruit flesh firmness in both years at 1% level (Fig. 2). That is, the fruit flesh firmness values decreased as the plant’s water consumption increased. As shown in Fig. 3, a significant inverse linear relationship was also determined between the fruit diameter and fruit flesh firmness.
Table 8 Skin colour as per irrigation treatments. Treatments
2008
2009
L
Fig. 3. Fruit diameter–flesh firmness relationship.
a
L
a
I1 Kcp1 I1 Kcp2 I1 Kcp3 I1 Kcp4
48.98 ab 47.63 ab 44.70 de 46.86 bcd
22.96 bc 23.52 bc 27.31 a 23.36 bc
42.25 a 41.02 ab 40.30 ab 41.29 a
25.50 d** 26.61 cd 29.75 a 26.56 cd
I2 Kcp1 I2 Kcp2 I2 Kcp3 I2 Kcp4
49.53 a 47.79 ab 43.27 e 44.92 cde
22.09 c 23.69 bc 26.41 ab 24.42 abc
41.71 a 42.05 a 40.36 ab 41.09 ab
26.99 bcd 27.12 bcd 28.18 abc 26.58 cd
Flood irrigation
47.10 bc
22.71 c
39.29 b
28.68 ab
*
**
*
I1 = 4 days, I2 = 7 days, Kcp1 = 0.50, Kcp2 = 0.75, Kcp3 = 1.00, Kcp4 = 1.25. Values with common letters do not differ significantly. * p < 0.05. ** p < 0.01.
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C. Küc¸ükyumuk et al. / Scientia Horticulturae 136 (2012) 17–23
Table 9 Correlation equations and coefficients among the examined plant components. Yield components Evapotranspiration (Et ) Fruit diameter Fruit length Fruit weight Fruit flesh firmness Fruit diameter Fruit flesh firmness * **
2008
2009
y = −2E−05x2 + 0.038x + 57.66 R2 = 0.59* y = −5E−05x2 + 0.074x + 44.41 R2 = 0.60* y = 8E−05x2 − 0.027x + 168.4 R2 = 0.49* y = −0.003x + 20.13 R2 = 0.72**
y = −1E−05x2 + 0.032x + 56.16 R2 = 0.56* y = 0.012x + 65.55 R2 = 0.53* y = −0.000x2 + 0.379x + 26.71 R2 = 0.54* y = −0.004x + 19.76 R2 = 0.87**
y = −0.145x + 28.50 R2 = 0.72**
y = −0.339x + 41.23 R2 = 0.68**
p < 0.05. p < 0.01.
4. Discussion 4.1. Vegetative growth According to the results of vegetative growth measurements, differences were determined among all treatments, but a clear relationship could not be identified. It is clear that transition from flood irrigation to drip irrigation method has positive effects on vegetative growth of apple trees. Plants spend most of their energies while taking water from the soil by their roots (Kocac¸alıs¸kan, 2005). Because the irrigation interval is long during flood irrigation, and the soil’s water decreases continuously after irrigation; roots of trees spend most of their energies during water intake, and spend less energy for growth and development. In drip irrigation, as the soil is more humid due to frequent irrigation interval, the trees do not spend much energy while taking water from the soil. They spend most of their energies for growth, development, productivity and fruit quality. Therefore the vegetative growth of drip irrigation treatments was positively influenced. Examination of shoot diameter, shoot length and shoot number figures of both years suggests an increase during drip irrigation treatments compared to those of flood irrigation. The reason of the increase in these values is the positive impact on vegetative growth. Similarly, Safran et al. (1975) pointed that fruit trees which had been irrigated for many years with surface irrigation methods did not indicate any reduction in vegetative growth after switching to drip irrigation, and drip irrigation had a positive effect on vegetative growth. Some researchers reported that different irrigation schedules on plum and pistachio trees and different irrigation methods on lemon trees had no effects on vegetative growth (Yıldırım and Yıldırım, 2005; Bilgel et al., 1999; C¸evik et al., 1993). 4.2. Fruit quality Positive effects of transition from flood irrigation to drip irrigation method were identified on fruit quality. Different irrigation programmes had different effects on fruit quality with drip irrigation during the study. Fruit diameter values increased as the pan coefficient increased but they decreased after Kcp3 (1.0) pan coefficient for both irrigation intervals. The lowest fruit diameter was obtained from the treatments with the lowest water (Kcp1 = 0.50) in drip irrigation (Table 5). The results of this study support the conclusions of Lord et al. (1963) and Landsberg and Jones (1981). Bergamini et al. (1990) reported for Golden Delicious apple variety that fruit diameter increased as the irrigation water amount in drip irrigation method increased. C¸ay et al. (2009) identified the highest fruit diameter in Kcp = 1.0 treatments for apple trees with drip irrigation method. Although fruit length values also increased
up to a certain level (Kcp3 = 1.0), they later decreased from that level (Kcp3 = 1.0) during the first year of the study. Nonetheless, an increase in fruit length values was identified with increased pan coefficient (Kcp ) in the second year. As expected, fruit diameter, length and fruit weight were lower in flood irrigation than drip irrigation treatments. With regard to fruit weight, the figures indicated an increase in the first year, up to (Kcp3 = 1.0), but a decrease was observed after that level (Kcp3 = 1.0). As similar curves were also noted in I1 treatments (4 days irrigation interval) during the second year; fruit weight values increased with increasing pan coefficients (Kcp ) in I2 treatments (7 days irrigation interval) (Table 5). An overall decline was observed for all values (fruit diameter, weight and length) as the irrigation intervals increased. Fruit diameter, length and weight values obtained from flood irrigation treatment were generally lower than those obtained from drip irrigation treatments. Flood irrigation treatment represented lower fruit quality figures. Different irrigation methods have different effects on fruit quality. Köksal et al. (1999) obtained the highest fruit diameter from drip irrigation method. Therefore, it is possible to say that drip irrigation method has more positive effects than flood irrigation method. Flesh firmness values decreased as the amount of irrigation water increased for both irrigation intervals of drip irrigation treatments during the study. The amount of irrigation water was noted as critical for fruit flesh firmness. Bonany and Camps (1998) already stated that flesh firmness of apples decreased as the amount of irrigation water increased. In general, total soluble solids values decreased as the amount of irrigation water increased. This result supports the findings of Morris et al. (1962) and Drake et al. (1981) who reported that the figures of total soluble solids content were higher for less irrigated fruits than excessively irrigated fruits. Flood irrigation treatment showed low soluble solid values for both years. The highest extra and class 1 fruit ratios were identified with drip irrigation treatments during the study. Flood irrigation treatment showed the lowest values. It has been identified that transition from flood irrigation method to drip irrigation increases the fruit size, which is an important marketing criterion for apple growing. Besides, obtaining the highest fruit diameter will be possible when Kcp3 (1.0) pan coefficient is used. Increased extra fruit ratio with drip irrigation was also observed by Köksal et al. (1999). An inverse ratio was identified between red colour density and fruit flesh brightness values during the study. An increase in red colour density (a) was identified as the fruit flesh brightness (L) decreased. Increasing irrigation water amounts affected red colour density in both irrigation intervals positively, but red colour density decreased after Kcp3 = 1.0 level. The highest red colour density figures were noted in Kcp3 = 1.0 treatments of drip irrigation.
C. Küc¸ükyumuk et al. / Scientia Horticulturae 136 (2012) 17–23
5. Conclusion According to the results of the study, it is concluded that transition from flood irrigation to drip irrigation method have positive effects on vegetative growth and fruit quality of apple trees which had previously been irrigated by flood irrigation for many years. An increase in fruit quality (marketable fruit diameter, fruit length, fruit weight, fruit skin colour) has been noted with drip irrigation method. The highest marketable fruit diameter was observed with Kcp3 (1.0) and Kcp4 (1.25) treatments. However, Kcp3 treatments are more preferable as they consume less irrigation water, thus result in saving water. To obtain a high quantity of marketable apples, Kcp treatment with 1.0 and irrigation interval with 4 days are recommended during transition from flood irrigation to drip irrigation for similar climatic and soil conditions. Apple growers should be encouraged to employ drip irrigation method instead of flood irrigation for a higher fruit quality and lower irrigation water consumption. Acknowledgement This study was summarized partially from the research project supported by the General Directorate of Agricultural Research and Policy, Food, Agriculture and Livestock Ministry, Turkey. References Anonymous, 2011a. Food and Agriculture Organization of the United Nations (FAOSTAT)., http://faostat.fao.org/site/291/default.aspx. Anonymous, 2011b. Turkey Republic, Institute of Statistics Prime Ministry, Ankara (official data). Bergamini, A., Angelini, S. and Bigaran, F., 1990. Influence of 4 different rootstocks on the stomal resistance and leaf water potential of Golden Delicious Clone B (Virus T Ree) Subjected to Different Irrigation Regimes. Societa Orticola Italiana, 1988, pp. 533–544 (Hort. Abstr. 60, 2256). Bilgel, L., Da˘gdeviren, I˙ ., Nacar, A.S., 1999. Determining irrigation scheduling and plant water consumption of Pistachio (Siirt variety) in GAP region Harran plain. In: Türkiye III. National Horticultural Congress, Ankara, pp. 252–257.
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Bonany, J., Camps, F., 1998. Effects of different irrigation levels on apple fruit quality. Acta Horticulturae (ISHS) 466, 47–52. C¸ay, S¸., Tarı, A.F., Dinc¸, N., Bitgi, S., Özbahc¸e, A., Palta, C¸., Okur, O., 2009. Effects of different irrigation programmes on yield and quality characteristics of Granny Smith apple variety grafted onto M9 rootstock. Journal of Agriculture Sciences Researches 2 (2), 73–79. C¸evik, B., Tuzcu, Ö., Kaplankıran, M., Yurdakul, O., Tekinel, O., Korkmaz, S., 1993. A study on determining the most suitable irrigation program for lemon trees in C¸ukurova plain. Turkish Journal of Agricultural and Forestry 17, 471–486. Drake., S.R., Proebsting, E.L., Mahan Jr., M.O., Thompson, J.B., 1981. Influence of trickle and sprinkle irrigation on Golden Delicious apple quality. Journal of American Society Horticulture Science 106 (3), 255–258. Ertek, A., Kanber, R., 2003. Effects of different irrigation programs on boll number and abscission percentage of cotton. Agricultural Water Management 60 (1), 1–11. James, L.G., 1988. Principles of Farm Irrigation System Design. John Wiley and Sons, Inc., New York, USA, p. 543. Kocac¸alıs¸kan, I˙ ., 2005. Plant Physiology. Dumlupınar University Faculty of Arts and Science, Department of Biology, Kütahya, 420 pp. Köksal, A.I˙ ., Dumano˘glu, H., Günes¸, N., Yıldırım, O., Kadayıfc¸ı, A., 1999. Effects of different irrigation methods and regimes on vegetative growth, fruit yield and quality of apple trees. Turkish Journal of Agriculture and Forestry 23, 909–920 (Additional press: 4). Landsberg, J.J., Jones, H.G., 1981. Apple orchards. In: Kozlowski, T.T. (Ed.), Water Deficits and Plant Growth, vol. VI. Academic Press, New York, pp. 419–469. Lord, W.J., Michelson, L.F., Field, D.L., 1963. Response to Irrigation and Soil Moisture Use by Mcintosh Apple Trees in Masachusetts. Experiment Station Publication, MA, p. 537. Morris, J.R., Kattan, A.A., Arrington, E.H., 1962. Response of Elberta peaches to the interactive effects of irrigation, pruning and thinning. Proceedings of the American Society for Horticulture Science 80, 177L 189. Önder, S., Kanber, R., Önder, D., Kapur, B., 2005. The differences of possibility of global climate changing on irrigation methods and management techniques. In: GAP IV. Congress of Agriculture, 21–23 September, pp. 1128–1135, S¸ANLIURFA. Safran, B., Bravdo, B., Bernstein, Z., 1975. L’irrigation de la vigue par goutte a gutte. Bulletin de l’OIV 48, 406–429. SPSS, 2003. SPSS 12.0 Copyright, SPSS Inc. USSL, 1954. Diagnosis and improvement of saline and alkali soils. Agriculture Handbook No. 60. USDA. Westwood, M.N., 1995. Temperate-zone Pomology, Physiology and Culture, third ed. Timber Press, Portland, Oregon, ISBN 0-8819-2253-6, 523 pp. Yıldırım, M., Yıldırım, O., 2005. The effects of different irrigation programmes on plum yield and tree growth in drip irrigation method. Uluda˘g University Journal of Agriculture Faculty 19 (1), 37–49.