ORIGINAL SCIENTIFIC PAPER
Effect of partial rootzone drying (PRD) on fruit quality and nutrient contents of ‘Albion’ strawberry Kujtim LEPAJA1, Lavdim LEPAJA1, Endrit KULLAJ1, Naim KRASNIQI2, Maxhun SHEHAJ1 1 2
Agricultural University of Tirana, Koder - Kamëz, 1029 Tirana, Albania, (e-mail:
[email protected]) University of Prishtina, Faculty of Agriculture and Veterinary, Boulevard Bill Clinton N.N., 10000 Prishtina, Kosovo
Abstract The quality and productivity of the trees are the result of continuous interaction of external environmental factors (climate, soil, agro and pomo techniques measures undertaken by man) and internal factors (genetic base of trees). The aim of this research was to determine the content of macro and micro-elements in strawberry fruits after the application of partial rootzone drying (PRD). Using a water budged methodology, four levels of irrigation, specifically 100% of ET (control) standard lateral, with two laterals (TL), side lateral (SL) and without irrigation (WI), were applied for each treatment we use 10 plants. The experiment was conducted in Kosovo during 2014 on a strawberry orchard of 1 ha on the first year of planting using a nested experimental design. Using ANOVA two-way with post hoc testing we found significant changes in P, Ca, Mg, Cu, Mn, Zn, Fe, Cr, Ni and Pb while changes were not significant for K and B. Key words: strawberry, Albion, irrigation, PRD, nutrient contents Introduction Water is the component through which strawberry takes nutrients dissolved in water with the help of the root system. In the absence of water, nutritional elements that found in soil can be used with difficulty from the root system (Zajmi et al., 2014). Controlled alternate partial root-zone irrigation (CAPRI), also called partial root-zone drying (PRD) in other literature, is a new irrigation technique and may improve the water use efficiency of crop production without significant yield reduction (Kang and Zhang, 2004), then PRD is a method for minimizing water use with little or no negative effects on fruit growth but causes a growth inhibition useful shoots (Kullaj, 2008). During the last decade a novel irrigation strategy, PRD, has been developed. The effective use of irrigation water has become a key component in the production of field crops and high-quality fruit crops in arid and semi-arid areas. Irrigation has been the major driving force for agricultural development in these areas for some time. Efficient water use has become an important issue in recent years because the lack of available water resources in some areas is increasingly becoming a serious problem (Kang and Zhang, 2004). PRD is a new irrigation technique that subjects one-half of the root system to a dry or drying phase while the other half is irrigated. The wetted and dried sides of the root system alternate on a 10-14-day cycle. Both RDI and PRD systems require high management skills. Close monitoring of soil water content is recommended. Both practices improve the WUE (water use efficiency) of wine grape production. Micro-irrigation facilitates the application of RDI and PRD. PRD uses biochemical responses of plants to water stress to achieve a balance between vegetative and reproductive development. By doing so, it achieves a secondary goal of significant improvement in production per unit of irrigation water applied. It has been a consistent feature of all trials that, even though the irrigation amount was halved, there was no significant reduction in yield due to PRD treatment. This contrasts with RDI experiments, where savings in irrigation application have often been at the expense of yield (FAO, 2002).
Proceedings . 50th Croatian and 10th International Symposium on Agriculture . Opatija . Croatia (600–604)
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50th Croatian and 10th International Symposium on Agriculture
Effect of partial rootzone drying (PRD) on fruit quality and nutrient contents of ‘Albion’ strawberry
According (Liu et al., 2007) in their study PRD had no advantage so they cannot be recommended under similar conditions. It is suggested that plants under PRD performs better than under deficit irrigation (DI) when the same amount of water was applied (Kirda et al., 2004; Davies and Hartung, 2004) cit. Liu et al., 2007. These authors proposed that PRD could stimulate root growth and maintain a constant ABA signaling to regulate shoot physiology; whereas plants under DI, some of the roots in dry soils for long period may die and signaling may diminish and shoot water deficits may occur. Accordingly, it is plausible to suggest that PRD maybe promising for strawberries. The objective of this study was to determine the impact of PRD on the nutrient elements where water resources are limited. Material and methods The experimental set up was a nested design, with plant of cv. ‘Albion’ strawberry. Four levels of irrigation were applied, 100% of evapotranspiration (ET) as control standard lateral (one lateral), with two laterals, side lateral and without irrigation. Orchard is planted on March 2014. Drip distance in the lateral pipe was 0.30 m while drip irrigation spend 1.28 liters of water/h per drip. A total of 9 irrigations (one irrigation is made per two hours) were applied. Partial rootzone drying (PRD) is started to applied from July until end of the August. For each treatment we used 10 plant (5/m2), totalling 40 plants for the entire experiment. Two fruits from each plant were sent to the laboratory where the following quality indicators were analysed: Ca, K, Fe, Cu, Mg, Zn, P, B, Mn, Cr, Ni and Pb. Data from the measurements were analysed using ANOVA two–way with post hoc testing. Table 1. Meteorological data for a multi-year period and 2014 Rainfall (mm)
Temp °C avg
Rainfall (mm)
Temp °C avg
Rainfall (mm)
Temp °C avg
Kosovo
Kosovo
Prishtina
Prishtina
Prishtina
Prishtina
30-year-avg
30-year-avg
30-year-avg
30-year- avg
2014
2014
January
61.8
-0.9
36.7
-1.2
10.8
3.5
February
53.0
1.7
36.8
1.3
21
6.7
March
51.0
5.3
35.3
4.8
50
8.4
April
56.5
10.0
51.4
9.8
228
10.4
May
75.9
14.8
75.3
14.4
71.0
14.5
June
60.4
18.3
56.9
18.0
88.4
18.5
July
53.0
20.1
48.6
19.7
75.6
20.8
August
45.8
19.9
46.2
19.8
9.0
21.9
September
55.1
16.0
47.5
15.8
152
16.0
October
70.1
10.6
56.1
10.5
-
-
November
87.1
6.1
64.2
5.8
-
-
Month
December
75.1
1.2
53.5
0.7
-
-
Total
744.8
10.3
608.0
10.2
-
-
Avg. veg.
346.7
16.5
325.9
16.3
-
-
Kosovo has a moderate continental climate with a coastal impact which penetrates through the valley of the Drini i bardhë moderating markedly continental climate elements (Lepaja et al., 2013). In Kosovo (Table 1) average temperature multiyear (1951-1980) is 10.3 °C, that of vegetation 16.5 °C, the coldest month is January (-0.9 °C) while the hottest month is July with 20.1 °C. Regarding the annual rainfall is 744.8 mm, and during vegetation is 346.7 mm which shows the need to intervene with supplementary irrigation. In Prishtina average temperature multiyear is 10.2 °C, that of vegetation 16.5 °C. Regarding the annual rainfall is 608 mm, and during vegetation is 325.9 mm which shows the need to intervene with supplementary irrigation (Zajmi, 1996). In Pristina in 2014 when the experiment was conducted are presented only data up to September and as seen
Section 9 . Pomology
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Kujtim LEPAJA, Lavdim LEPAJA, Endrit KULLAJ, Naim KRASNIQI, Maxhun SHEHAJ
during these months there were numerous rainfalls (especially on April to 228 mm) which has not happened in Kosovo that the amount of rainfalls during the vegetation exceed the total amount of rainfall throughout the year. Results and discussion At present and more so in the future, irrigated agriculture will take place under water scarcity. Insufficient water supply for irrigation will be the norm rather than the exception, and irrigation management will shift from emphasizing production per unit area towards maximizing the production per unit of water consumed, the water productivity (Fereres and Soriano, 2007). Table 2 summarises the results of the application of PRD on the quality parameters of Albion strawberry we found significant changes in P, Ca, Mg, Cu, Mn, Zn, Fe, Cr, Ni and Pb while changes were not significant for K and B. Statistical differences were at the level 0.01, where for seven elements differences between treatments were the same as seen in the graph 1. (for Cu, Cr, Pb, Ni, Mn, Mg and Fe) while for Ca and Zn differences were only between without irrigation treatments with all other treatments. However, until now PRD has not been studied in strawberry under field conditions (Liu et al., 2007), but these result refer in agro-ecological conditions in which it is conducted experiment. The use of the four different levels of irrigation (normal irrigation, two laterals, side lateral and without irrigation) increases our understanding of the effects of regulated water deficit practices, respectively PRD practices. Table 2. Means of mineral contents in fruit at harvest
602
Elements
Normal irrigation (standard lateral)
Two laterals
Side lateral
Without irrigation
Ca
234.35
255.47
244.95
330.39
K
1642.32
1825.11
1601.30
1690.02
Fe
22.93
28.61
32.25
39.05
Cu
1.08
1.44
2.93
2.21
Mg
120.67
114.30
119.87
135.14
Zn
4.13
4.56
4.23
5.24
P
187.98
148.03
142.02
291.23
B
37.91
43.79
54.46
60.67
Mn
2.98
4.12
3.78
3.36
Cr
0.09
0.10
0.08
0.11
Ni
0.09
0.10
0.06
0.10
Pb
0.13
0.16
0.14
0.17
50th Croatian and 10th International Symposium on Agriculture
Effect of partial rootzone drying (PRD) on fruit quality and nutrient contents of ‘Albion’ strawberry
Graph 1. Differences between treatments according LSD testing
Section 9 . Pomology
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Kujtim LEPAJA, Lavdim LEPAJA, Endrit KULLAJ, Naim KRASNIQI, Maxhun SHEHAJ
Conclusions Based on our investigations on the partial rootzone drying under the agroecological conditions of Kosovo, and Vushtrria in particular under an intensive strawberry growing technology, the following conclusions can be drawn: Based on the analysis of variances all statistical differences were observed in the level 0,01 per these elements (Cu, Cr, Pb, Ni, Mn, Mg, P and Fe) for which the differences between treatments were the same, for Ca and Zn differences were only between without irrigation treatments with all other treatments while for B and K are not found differences. These results can be obtained primarily as a result of weather conditions: temperature and rainfall during the time the experiment. Long-term effects of deficit irrigation, together with climatic conditions and crop techniques variations, must be considered, because the long-term plant responses to PRD may be different from short-term responses. References Davies, W.J., Hartung, W., 2004. Has extrapolation from biochemistry to crop functioning worked to sustain plant production under water scarcity? In: Proceeding of the Fourth International Crop Science Congress, 26 September–1 October, 2004, at Brisbane, Australia. FAO 2002. Deficit irrigation practices. Water report. Rome. pp. 79-87. Fereres E., Soriano Maria. 2007. Deficit irrigation for reducing agricultural water use. Journal of Experimental Botany. Vol. 58, No. 2, pp. 147-159. Kang, S., Zhang, J. 2004. Controlled alternate partial root-zone irrigation: its physiological consequences and impact on water use efficiency. J. Exp. Bot. 55 (407), 2437–2446. Kirda, C., Cetin, M., Dasgan, Y., Topcu, S., Kaman, H., Ekici, B., Derici, M.R., Ozguven, A.I. 2004. Yield response of greenhouse grown tomato to partial root drying and conventional deficit irrigation. Agric. Water Manage. 69, 191–201. Kullaj, E. 2008. Ekofiziologjia e drufrutorëve. FBM. UBT. Tiranë. pp. 314. Lepaja L., Kullaj E., Lepaja K., Shehaj M., Zajmi A. (2013). Fruit quality parameters of five pear cultivars in western Kosovo. Journal of International Scientific. Vol. 2:245-250 Liu F., Savić S., Jensen C.R., Shahnazari A., Jacobsen S.E., Stikić R., Andersen M.N. 2007. Water relations and yield of lysimeter-grown strawberries under limited irrigation. Scientia Horticulturae 111 (2007) 128–132. Zajmi A. (1996). Mundësitë e shfrytëzimit të potencialeve natyrore dhe biologjike në prodhimtarinë bujqësore në Kosovë. Konferencë shkencore. Seksioni i shkencave të natyrës. ASHAK. Prishtinë. pp. 201-220. Zajmi A., Lepaja K., Lepaja L. (2014). Kultivimi i dredhëzës. Dija. Prishtinë. pp 43-102. sa2015_p0910
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