Abo El-Fadel, N., Shama, M. (2020). Foliar Application of Glycine Betaine and Potassium Silicate and Its Effect on Growth Performance of Jerusalem Artichoke Grown on Calcareous Soil Under Water Stress Conditions. Journal of the Advances in Agricultural Researches, 25(1), 14-37. doi: 10.21608/jalexu.2020.163749
Nashwa Ibrahim Abo El-Fadel; Mostafa Ahmed Shama. "Foliar Application of Glycine Betaine and Potassium Silicate and Its Effect on Growth Performance of Jerusalem Artichoke Grown on Calcareous Soil Under Water Stress Conditions". Journal of the Advances in Agricultural Researches, 25, 1, 2020, 14-37. doi: 10.21608/jalexu.2020.163749
Abo El-Fadel, N., Shama, M. (2020). 'Foliar Application of Glycine Betaine and Potassium Silicate and Its Effect on Growth Performance of Jerusalem Artichoke Grown on Calcareous Soil Under Water Stress Conditions', Journal of the Advances in Agricultural Researches, 25(1), pp. 14-37. doi: 10.21608/jalexu.2020.163749
Abo El-Fadel, N., Shama, M. Foliar Application of Glycine Betaine and Potassium Silicate and Its Effect on Growth Performance of Jerusalem Artichoke Grown on Calcareous Soil Under Water Stress Conditions. Journal of the Advances in Agricultural Researches, 2020; 25(1): 14-37. doi: 10.21608/jalexu.2020.163749
Foliar Application of Glycine Betaine and Potassium Silicate and Its Effect on Growth Performance of Jerusalem Artichoke Grown on Calcareous Soil Under Water Stress Conditions
1Sabaheya Horticultural Research Station, Horticulture Research Institute, A.R.C., Egypt.
2Soil Salinity Department; Soil, Water, and Environment Research Institute; A.R.C., Egypt.
Abstract
This investigation aims to evaluate the effect of water stress and foliar application of two different antitranspirants on growth, yield, quality and water use efficiency of Jerusalem artichoke grown a calcareous soil using drip irrigation system. For this purpose, two field experiments were carried out at soil salinity lab. Res., Agricultural Research Center, Alexandria Governorate, Egypt during the summer seasons of 2017 and 2018 using the split plot design. Jerusalem artichokeplants were irrigated by 100, 75 or 50% of water requirements (ETC). The antitranspirants included glycine betaine (200 mg/l), potassium silicate (5 cm3/l) and their combination i.e. potassium silicate (P.S) x glycine betain(G.B) in comparison with spraying distilled water as control treatment. The gained results revealed that increasing irrigation water levels from 50% up to 100% significantly (P<0.05) increase, majority of plant vegetative growth characters Jerusalem artichoke tubers yield/feddan, its component parameters and tubers′ quality during both seasons. Foliar application of antitranspirant treatments; increased irrigation efficiency and potassium silicate was more effective than glycine betaine, in particular, upon irrigation with 50% ETC treatment. In general, spraying Jerusalem artichoke plants with potassium silicate; gave rise to the best results for plant height, No. of main stem/plant and plant fresh weight/plant with 100% ETC during both seasons. The dry matter percentage was not affected significantly (P>0.05) by the two independent variables. In addition, potassium silicate at 100% ETc; brought about the highest value for tuber yield in both seasons. Jerusalem artichoke plants irrigated with 75% of water requirements gave insignificant decrease in number of tubers/plant, tuber fresh weight and tuber yield than the treatment received 100% of water requirements. The interaction between irrigation tested levels and foliar application treatments was highly effective on tuber yield character in both seasons. The highest average values for tuber yield/feddan were recorded due to the treatments of water level of 75%ETc with spraying potassium silicate at 5cm3/ l., while the lowest mean values were achieved due to apply at 50 % irrigation level compare with control treatment. Also, the interaction between irrigation levels foliar glycine betaine, potassium silicate, and G.B. x P.S. had a significant (P<0.05) effect on K of tuber content during both seasons. The compositional elements N, P and carbohydrate content in tubers were not significantly affected by this interaction during the two seasons except inulin content during the first season only. The best results were recorded due to apply water irrigation level of 100% ETC and 75%ETC with spraying of potassium silicate at 5cm3 /l.Crop water use efficiency (CWUE) was doubled in the case of 50% ETC compared with consumptive 100% ETC. The water use efficiency increased as the irrigation level reduced.
Jerusalem artichoke (Helianthus tuberosusL.) also called as sunchoke, and belongs to family Compositae (Asteraceae). Studies on nutritive value of Jerusalem artichoke tubers have revealed that they contain many important components( Praznik et al., 1998). It is also a better source for inulin and oligofructose, which are types of fibers that act as potent prebiotics, or food for probiotics. Denoroy (1996) reported that inulin is a soluble fiber that balances blood sugar. Moreover, soluble carbohydrates present beside inulin are its derivatives fructooligosaccharides, which are simple sugars (fructose and glucose) and saccharose. It was considered as a biomass crop for ethanol, also. The production of biogas from biomass is economically viable under certain conditions, and the possibility of increasing the cultivation of Jerusalem artichoke has increased the scientific interest about this crop (Gunnarson et al., 1985).
Stress caused by water is an increasing environmental constraint in agriculture, cause several damage effects on plant growth and metabolic processes, including water relations, photosynthetic assimilation, and nutrient uptake (Stone et al., 2001). The damage caused by water stress is one of the most important environmental stresses that cause heavy loss to the agriculture worldwide (Kumar et al., 2012). Water is essential and the plants should receive at least 1 inch per week to produce better tuber growth. The researchers indicated that vegetables are more sensitive to water stress compared to other crops. Flowering of Jerusalem artichoke begins in August and when the plants begin to brown in September, it’s time to harvest its tubers. The main problem that the agricultural production faces is the shortage of irrigation water. Under these conditions, crop water use efficiency, crop water content are seriously affected, leading to low net photosynthetic rate, growth decline, and storage root yield lack (Van Heeden and Laurie, 2008; Yooyongwech et al., 2016). Therefore, an effective technique and agricultural practices are required urgently to save water for expansion of agricultural area and other purposes.
One of the approaches to reduce the negative effects of water deficiency is the foliar application by potassium silicate which aimed to improve growth and increase productivity under water stress (Kamal, 2013). Potassium silicate promotes the vegetative growth, yield components and mineral nutrient concentrations such as nitrogen, phosphorus and potassium elements in potato crop (Salim et al., 2014). Potassium is very important for both the basic physiological functions of plants, such as the formation of sugars and starch, proteins synthesis, cell division, growth and fruit formation. Potassium, also, affects the synthesis, conversion and storage of carbohydrates as well as the quality of potato tubers (Ebert, 2009; Dkhil etal., 2011).
Glycinebetaine(GB) is a quaternary ammonium compound which found naturally in a wide variety of plants, animals and microorganisms. The accumulation of GB is induced and synthesized in the chloroplasts of higher plants under variety of abiotic stress, such as high salt, water stress and cold (Jagendorf and Takabe,2001;Rontein et al.,2002), and the exogenous GB could enhance the resistance ability to water stress (Mahouachi et al.,2012). Glycinebetaine affords osmoprotection for plants and protects cell components from harsh conditions by functioning as a molecular chaperone (Sakamoto and Murata, 2002). Application an exogenous of GB improves the growth and survival of a wide variety of plants under several of abiotic stress conditions (Ashraf and Foolad 2007; Hoque et al., 2007; Park et al., 2006 and Chen and Murata, 2008). On the other hand, the antitranspirants reduces the water decrease during vegetative growth period and before or after fruits harvesting (Abd El Aal et al., 2008).
This study aims to assess the effect of foliar spraying with potassium silicate, glycine betain as two different antitranspirants and irrigation water stress on growth, yield and tubers' quality of Jerusalem artichoke crop and to determine the actual ET for Jerusalem artichoke plants.
Materials and methods
Field experiments:
Two field experiments were conducted during two successive summer seasons of 2017 and 2018 in the soil salinity lab. Res. Alexandria, Agricultural Research Center. Jerusalem artichoke plant (Helianthus tuberosus L.) cultivar Fuseau was used in this investigation. Planting tubers was done on April, 10th and 9th during growing seasons, respectively. Tuber seeds were planted at 60 cm apart on one side of the ridges within rows of 60 cm width and 4 m length. The physical and chemical properties of the experimental soil used were done and shown in Table (1), which had been determined according to Black (1965).
Soil type
Particle size distribution (%)
Soil Texture
Soil apparent
density (g /cm3)
Soil moisture content (Volumetric %)
pH
EC dS/m
CaCO3
%
O.M.
%
Sand
Silt
Clay
Field capacity
Witling point
Calcareous
55
25
20
sandy clay loam
1.28
29
16
8.1
1.78
32.6
1.45
Table (1). Some physical and chemical properties of the experimental soil (average values of both seasons)
Experimental design and treatments
The experimental design used was a split-plot design with three replicates. Three irrigations levels 50%, 75% and 100% of crop evapotranspiration (ETc) were assigned to main plots. The sub plots were devoted to four foliar applications included sprayed with distilled water as control, liquid potassium silicate (K2SiO3) 10 % K2O and 25% SiO2 and potassium silicate at rate of 5 cm3/l, glycin betain [(Carboxymethyl) trimethyl ammonium inner salt,( C5H11NO2, MW: 117.146 g/mole) at 200 mg/l and their combination i.e., potassium silicate (P.S.) x glycine betain (G.B.) foliar together. Foliar applied was done twice at 60 and 90 days after planting. Tween-20 (0.1%) was used as a wetting agent for each treatment. Each experimental sub plot consisted of two rows. The irrigation treatments started after 20 days of transplanting. During the first 20 days (initial stage), the Jerusalem artichoke plants were irrigated according to the calculated irrigation requirements, while in other stages (development, mid, and end) the plants irrigated by 100, 75 or 50% of water requirements using drip irrigation method. The following fertilizers were added to the soil at preparation before planting: 20 m3 organicmanure/fed. plus calcium super phosphate fertilizer (15.5% P2O5) was base dressed during soil preparations as recommended (150 kg ∕ fed.). Nitrogen fertilizer was added in the form ammonium nitrate (33.5% N) at the rate of 300 kg ∕ fed. at three equal doses ; after four, eight and twelve weeks from planting. Potassium sulphate (48% K2O) was applied at rate of 90 kg ∕ fed. in two equal doses eight and twelve weeks after planting. During the growing seasons, all other recommended agro-managements such as disease pests and weed control were performed whenever they appeared to be necessary.
The crop evapotranspiration (ETc) was determined by using CROPWAT 8.0 a computer program and according to Penman-Montieth equation (Allen et al., 1998). Meteorological data (2017 and 2018) were obtained online from Weather Station (latitude of 31°11′02″ N, longitude of 29°56′54″ E and altitudeof-2 m) in Alexandria-Nouzha Airport, Egypt at 4.5 km from experimental site location (Table 2).
Table(2). Average monthly maximum and minimum temperatures(oC), relative humidity (RH%) and wind speed (km/h) in the experimental location during 2017 and 2018 growing seasons
Month
Minimum temperature
( oC )
Maximum temperature
( oC )
Relative humidity
( % )
wind speed (km/h)
Minimum temperature
(oC )
Maximum temperature (oC )
Relative humidity
( % )
wind speed (km/h)
Season 2017
Season 2018
May
22
29
58
16
21
27
70
18
June
23
28
66
15
24
29
68
16
July
25
29
69
17
25
30
71
18
August
26
31
62
15
26
31
68
16
September
24
29
62
16
25
30
64
16
October
22
27
55
17
23
27
59
17
November
18
23
58
15
17
24
65
13
Calculation of irrigation water requirements (IR)
Based on the climate data in Table (2), the ETc values for Jerusalem artichoke were calculated in Table (3). The Crop water consumptive use (CU) is the amount of water equal to what is lost by plant while irrigation requirement (IR) depends on Cu, irrigation method and leaching fraction. Both Cu and IR estimation is derived from crop evapotranspiration (ETc) which can be calculated by the following equation:
ETC = KC. ET0
Where; KC is the crop coefficient. Crop coefficients values used for Jerusalem artichoke were 0.35, 0.60, 1.00, 0.35 for growth stages initial, development, mid, and end, respectivelyas suggested by(Baldini et al., 2011). It is the ratio of the crop ETc to the ET0 (Pereira et al., 2015). The Kc coefficient serves as an aggregation of the physical and physiological differences between crops. The daily reference evapotranspiration (ETo) was estimated using Penman–Monteith’s modified equation (Allen et al., 1998). The ETC and is expressed by the rate of mm/day. The data in Table (3) show the actual evapotranspiration, consumptive water use and irrigation water applied at different water stress during the seasons of 2017 and 2018.
Table (3). Average values of reference evapotranspiration (ETO, mm / day), actual evapotranspiration (ETC, mm), and crop coefficient (kC) at plant growth during of 2017 and 2018 seasons
Months
ETO (mm/day)
KC
ETC (mm/day)
ETc (mm/month)
ETO (mm/day)
KC
ETC (mm/day)
ETC (mm/month)
Season 2017
Season 2018
May
5.57
0.44
2.45
46.27
5.59
0.44
2.46
55.52
June
6.50
0.58
3.78
83.55
6.47
0.51
3.34
100.29
July
7.07
0.99
6.97
217.09
6.59
0.99
6.49
201.29
August
6.82
1.19
8.12
251.95
6.51
1.19
7.75
240.05
September
6.07
1.18
7.18
215.41
6.08
1.18
7.19
215.63
October
5.57
0.79
4.40
138.00
5.37
0.79
4.27
130.43
November
3.99
0.44
1.76
45.97
3.64
0.48
1.75
22.52
ETC mm/season
998.24
965.73
Calculation of water use efficiency
In the drip irrigation treatments, daily consumptive use (CU) of water was worked out based on the crop ET and at the end of the season the seasonal consumptive use of water was calculated and expressed in mm. Crop water use efficiency (CWUE) was calculated using the equation CWUE = Y / CU); where Y equals to the marketable tuber yield (kg/fed.), CU equals to the seasonal actual evapotranspiration ETC (as unit m3/fed.). Irrigation water use efficiency (IWUE) was estimated using the formula (IWUE = Y / IR) according to Bozkurt et al., (2009), whereas, IR irrigation requirement equals to the seasonal water applied to the field (m3/fed.) and calculated according to the equation: IR=CU/ [Ea*(1-LF)], where the application efficiency (Ea) for drip irrigation equal 0.85 and the leaching fraction (LF) was considered as 0.10 of water requirement.
Data recorded:
Vegetative growth characters :
A sample of three plants from each experimental plot was taken, randomly, at flower initiation stage (150 days after planting) to estimate plant height (cm), number of main stems, plant fresh weight (kg) and plant dry matter percentage.
Total tuber yield
Each plant in each experimental unit was taken at harvest time i.e. 180 days after planting to yield measure, number of tubers per plant, average tuber fresh weight (g/plant), total yield per plant( kg/plant) and total tubers' yield (ton / fed.).
Tuber’s quality and mineral content:
Ten tubers per treatment were token randomly, to determine tuber dry matter percentage calculated by drying 100 g of fresh sliced tubers in an electric air – drying oven at 70 °C till constant weight. Inulin content was determined in tubers according to the method of Winton and Winton (1958). Total carbohydrate was determined colorimetrically as gram of glucose /100g dry weight of tubers roots according the methods described by James (1995). In the digested dry matter of tubers nitrogen was determined according to the methods described by Pregl (1945) using micro-kjeldahl apparatus. Meanwhile, phosphorus was determined colorimetrically according to Murphy and Riley (1962). Potassium was determined against a standard using air propane flame photometer according to Chapman and Pratt (1961).
Statistical analysis:
Collected data from the experiments were statistically analyzed, using the analysis of variance method. Comparisons among the means of different treatments were done, using least significant differences (L.S.D) test procedure at p ≤ 0.05 level of probability, as illustrated by Snedecor and Cochran (1980) using Co-Stat software program (2004).
Results and Discussion
1- vegetative growth parameters
The results relevant to this research will be presented and dissection as follows:
The main effect of irrigation levels
Obtained results in Table (4) exhibit clearly that all the studied vegetative growth parameters i.e., plant height, number of main stems per plant, fresh weight of plant were significantly (p≤0.05) affected by irrigation levels treatments during both seasons of the growth. In this respect, decreasing the irrigation levels from 100 % of crop evapotranspiration (ETc) to 50% consistently and continuously; decreased all morphological parameters of plant. However, dry matter percentage of plant foliage did not significantly (p>0.05) affected by irrigation levels treatments during both seasons. Such increment in plant morphological parameters due to the reduction of irrigation levels may be due to the main role of irrigation water for increasing the availability and diffusion as well as the uptake of macro and micronutrients by plant, which affect, greatly, the plant growth. Also, the reduction in plant growth due to the deficiency of irrigation water might be due to the lack of water absorption by plant which in turn effect on the role of photosynthetic assimilation insufficient water condition. Moreover, deficit irrigation as a water stress condition eventually reduces plant growth, chlorophyll content, water potential and transpiration rate as well as the free water in plant tissue, leading to deleterious effect on photosynthetic rate, stomatal conductance and intercellular CO2 (Mingchi et al., 2010). Similar results, more or less, were recorded by (Cooper, 1980; Sharma et al. 1984; Abo-El Magd et al. 2007; Abo-Sedera et al. 2004).
b. The main effect of four foliar application
The results of Table (4) demonstrate foliar application of glycine betain, potassium silicate and interaction of them that exerted significant (p≤0.05) effects on vegetative growth characteristics of Jerusalem artichoke plants except for plant dry matter percentage. It is clear that vegetative growth characteristics, increased significantly i.e., plant height (cm), number of main stems and plant and fresh weight (kg) were recorded when the growing plants sprayed with potassium silicate and the interaction of G.B. x P.S. compared with G.B. and control treatments during both growing seasons. Salim et al. (2014) and Abd El-Gawad et al. (2017) reported that potassium has an effect on photosynthesis, which is positively affect the vegetative growth of potato plant. It could be taken place due to the role of potassium on plant nutrition, i.e. promotion of enzymes activity and enhancing the translocation of assimilates and protein synthesis. Also, Sangakkara et al. (2000) ascribed the increase in the vegetative growth of potato plants to the role of K in biochemical pathways in plants and it amplifies the photosynthetic rates, CO2 assimilation and facilitates carbon movement. Marschner (2012) reported that Potassium is a significant nutrient for numeral of physiological function, counting regulation of water and gas exchange in plants, protein synthesis, enzyme activation, photosynthesis and carbohydrate translocation in plants. Pilon et al. (2013) found that leaf area of potato plants increased because of silicon application. Similarly, silicon application reflected an increase in the leaf area and haulm dry weight readings (Abd El-Gawad et al., 2017). The enhancement effect of silicon on the vegetative growth could be attributed to activating antioxidant defense system or through their protective effect on the photosynthetic pigments in salt stressed plant (Ashraf et al., 2010). Romero-Aranda and Cuartero (2006) found that treating tomato plants with potassium silicate (K2SiO3) as a source of silicon (2.5 mM); improved leaf fresh, weight, area and net photosynthesis rate as well as water storage within plant tissues. Furthermore, Abou-Baker et al . (2012) indicated that spraying faba bean plants with silicon at 300 ppm as potassium silicate; recorded the highest significant average values of plant height, root length, shoot and root dry weight. In this respect, Soja et al., (1990), Mansour et al. (2001), Tawfik et al. (2003) and Abo-El Maged et al. (2007) recorded, more or less, similar results on Jerusalem artichoke.
The application of glycine betaine; produced the highest average values in the most of vegetative growth parameters during both season. However, this increment did not reach the level of statistical significant when compared with foliar application of potassium silicate and interaction of them on plant fresh weight in the first season and plant dry matter percentage both season of the study. In this content, Osman (2009) found that application of 1 mM glycine betaine increased flag leaf area of rice. In addition, Abbas et al. (2010) found also that foliar application of G.B. caused improvement in growth of two eggplant cultivars. The growth improvement could be taken place due to G.B. as enhance for photosynthetic rate and stomatal conductance. In the other words, glycine betaine was effective in stimulating plant growth compared to the control treatment.
Table(4). Average values of some vegetative growth characters as affected by irrigation levels and four foliar applications of glycine betaine, potassium silicate and their interactions on Jerusalem artichoke plant during 2017 and 2018 seasons
Treatments
Vegetative growth characters
Season 2017
Season 2018
Irrigations levels
Foliar application
Plant height (cm)
No. of main stem / plant
Plant
fresh
weight
(kg)
Plant
D.M
(%)
Plant height (cm)
No. of main stem / plant
Plant
fresh
weight
(kg)
Plant D.M
(%)
100% ETc
control
196d
6.9abc
5.22a
10.56a
232d
8.5b
4.78e
11.80a
G.B. (200mg/l)
233b
8.2a
5.41a
10.83a
245bc
9.5a
5.98ab
11.61a
P.S.
(5 cm3/l)
296a
9.8a
5.63a
10.87a
261a
10.9a
6.31a
11.48a
G.B. x P.S.
215c
8.8a
5.49a
10.69a
234d
8.5b
6.03a
11.75a
75% ETc
control
188d
7.1ab
3.23c
10.55a
210e
9.4a
5.21c
11.42a
G.B. 200mg/l
180de
6.6bc
4.03b
11.22a
242b
9.8a
5.47bc
13.40a
P.S5 cm3/l
193d
6.5bc
4.36b
11.52a
266a
10.3a
5.89b
12.94a
G.B x P.S
185de
6.5bc
5.08a
11.56a
256b
9.6a
5.44bc
12.66a
50% ETc
control
164fg
4.7e
3.02c
11.41a
172gh
7.4c
3.54f
14.51a
G.B 200mg/l
169fg
5.2cd
4.22b
12.56a
177g
8.0c
4.45ef
14.66a
P.S5 cm3/l
173f
4.6e
3.52c
13.74a
198f
8.5b
4.65e
14.58a
G.B. x P.S.
175f
4.2ef
3.54c
13.40a
178g
8.8b
4.69e
14.98a
Irrigations levels
100% ETc
210.16a
7.3a
5.84a
10.78a
288.16a
10.3a
5.89a
13.56a
75% ETc
195.12b
5.2b
4.43b
11.56a
259.26b
9.6a
5.22a
13.98a
50% ETc
153.43c
3.6c
3.20c
14.22a
185.33c
7.6b
3.69b
14.33a
Foliar application
control
166.13c
5.5c
4.23c
12.14a
188.23c
7.8c
5.50c
12.45a
G.B.(200mg/l)
185.65b
6.4b
5.56b
12.66a
243.12b
8.4b
6.78b
12.54a
P.S.( 5 cm3/l)
189.62a
7.5a
5.64b
13.51a
274.36a
11.0a
7.94a
13.55a
G.B. x P.S.
195.48a
7.1a
6.88a
12.87a
268.48a
10.4a
7.98a
13.45a
Values followed by the same letter (s) within column are not significantly different (P<0.05)
C. The effect of tested interaction
The given results of Table (4) indicate that the given interactions exerted significant effect (p ≤ 0.05) on plant height, No. of main stem / plant and plant fresh weight/plant. In general, foliar application of Jerusalem artichoke plants with potassium silicate of 5 cm3/l and G.B. x P.S., gave the best results for the characteristics of plant height, No. of main stem/plant and plant fresh weight/plant with 100% of crop evapotranspiration (ETC) of irrigation levels applied during in both seasons. As mentioned -earlier, the characteristic of dry matter percentage was not affected by the two independent variables; this trait was not affected significantly (P> 0.05) by the interaction between these two variables.
2. Yield and yield components
The results outlined in Table (5) indicate that Jerusalem artichoketuber yield and its component characters were significantly affected (p ≤ 0.05) by the two studied independent variables (irrigation water levels and foliar spraying with potassium silicate, glycine betain and G.B x P.S) during both seasons.
a. The main effect of irrigation level
regarding to the irrigation levels as a main effect, the results of Table (5) appeared that there is a clear positive relationship between increasing the irrigation levels and the total tuber yield and its components (number and weight of tuber /plant, average tuber weight as well as total yield/fed.) during the two seasons of the growth. In this respect, the highest average values were recorded for such characters were at 100% ETC followed by75% ETC, while the lowest average values were recorded at 50%ETc. Total yield per plant (kg) was the only character that affected significantly (p ≤ 0.05 by irrigations levels in the first season. On the other hand, the tuber dry matter percentage was not significantly affected during the two seasons. It is known that the total yield and its components were highly correlated with the vigorous of the vegetative growth. These results might be attributed to lack of water absorbed and inhibition of photosynthesis efficiency under insufficient water conditions (Abo- El Maged et al., 2007). Similar results, more or less, were obtained by Smittle et al, (1990) and Abd –El Aal (2011) on sweet potato.
b. The main effect of foliar application
With regard to the main effect of foliar applicants variable, the result of (Table 5) demonstrate that Jerusalem artichoke tuber yield trait and its component characters were significantly (p ≤ 0.05) affected with (glycine betain at 200mg/l, potassium silicate of 5 cm3/l and their interaction compared with control treatment during both seasons. In this respect, No. of tubers per plant, total yield per plant and total yield per fed. were affected significantly(p ≤ 0.05) owing to foliar application of potassium silicate 5cm3 / l and because the interaction G.B. x P.S. during both seasons. Average tuber fresh weight trait was affected significantly (p ≤ 0.05) by four foliar application treatments in the first season only. On the other hand, tuber dry matter percentage was not affected significantly by the four foliar application treatments during the two seasons. In this regard, spraying potassium silicate at 5cm3/l significantly (p ≤ 0.05) gave rise to the highest average values, followed by spraying with the interaction (G.B. x P.S.) then spraying glycine betain at 200 mg/l, and finally control treatment, which significantly (p ≤ 0.05); recorded the lowest average values for the three traits. Abd El-Baky et al. (2010) reported that sweet potato total yield per plant and total yield / feddan illustrate positively response to supplying the potassium. The promising effects of four foliar spraying applications with potassium silicate, glycine betain, interaction (G.B. x P.S.) and control treatment on Jerusalem artichoke increasing yield/fed., and its component characters might be attributed to its profound effects on enhancing vegetative growth traits (Table, 4) and the role of potassium as a macroelement in assimilation and translocation of plant synthetic assimilated molecules from the organs of synthesis to the storage organs (tubers). This result is consistent with the confirmed by Soja et al.( 1990), Mansour et al. (2001), Tawfik et al. (2003) and Abo-El Magde et al. (2007) in their study on Jerusalem artichokecrop.
Table (5). Average values of yield and its components of Jerusalem artichoke as affected by irrigation levels and foliar application of glycine betaine, potassium silicate and their interaction treatments during 2017 and 2018 seasons
Treatments
Season 2017
Season 2018
Irrigations levels
Foliar application
No. of
tubers/
plant
Average
Tuber fresh
weight
(g)
Total
yield/plant
(kg)
Total
Yield/fed.
(ton)
Tubers dry matter%
No. of
tubers/
plant
Average
tuber
fresh
weight
(g)
Total
yield/plant
(kg)
Total
yield/fed.
(ton)
Tubers dry matter%
100% ETc
control
49.23d
33.12e
2.061d
13.690c
16.45f
52.36e
42.89a
3.189b
13.026b
20.45a
G.B. 200mg/l
65.42b
41.23b
3.556bc
14.813ab
17.72de
66.45c
43.23a
3.838ab
14.254a
20.54a
P.S.5 cm3/l
70.02a
38.69c
3.891b
15.023a
18.23d
73.25a
47.55a
4.431a
14.910a
19.87a
G.B. x P.S.
68.33ab
45.20a
4.030a
15.014a
18.36d
70.45b
46.21a
4.220a
15.451a
20.36a
75% ETc
control
46.22e
40.23bc
2.800
13.012c
17.52de
50.02f
40.12a
3.012b
13.254b
22.63a
G.B. 200mg/l
55.80c
42.33b
3.310c
13.456c
19.14cd
55.63d
43.55a
3.226b
13.894b
22.05a
P.S5 cm3/l
70.41a
45.51a
4.090a
15.353a
21.56b
74.25a
49.12a
4.626a
15.256a
21.53a
G.B. x P.S.
68.21ab
42.36b
3.856b
15.162a
20.32bc
69.66b
48.06a
4.312a
14.963a
20.14a
50% ETc
control
38.54f
39.21c
2.650d
10.456e
22.36b
40.63i
44.54a
2.160c
11.560de
22.58a
G.B. 200mg/l
45.21e
33.65e
2.881d
12.145d
24.63a
45.23h
43.12a
2.485c
12.681bcd
22.36a
P.S 5 cm3/l
49.02d
36.44d
2.764d
12.365d
23.58a
47.21g
45.23a
2.692c
12.873bc
21.45a
G.B. x P.S.
48.33d
32.55ef
2.536d
12.045d
24.12a
46.23g
43.45a
2.518c
12.895bc
20.14a
Irrigations levels
100 % ETc
57.21a
56.32a
4.192a
15.456a
20.56a
66.23a
58.63a
4.828a
16..651a
19.22a
75 % ETc
54.23a
53.21a
3.862b
14.253a
22.14a
64.25a
55.36a
4.520a
16.058a
22.51a
50 % ETc
43.54b
48.45b
2.064c
12.687b
23.56a
49.23b
52.14a
3.548a
13.054b
23.17a
Foliar application
control
50.12c
46.25c
2.300c
12.023d
23.15a
52.63c
48.55a
3.496c
13.526b
20.36a
G.B. (200mg/l)
55.45b
49.89b
3.695b
14.258c
23.52a
58.93b
49.22a
3.842b
14.520a
22.04a
P.S. (5 cm3 / l)
60.90a
53.76a
4.180a
15.265a
23.88a
62.31a
49.56a
4.036a
15.423a
22.14a
G.B x P.S
60.89a
51.66a
4.060a
14.956a
22.51a
65.32a
48.09a
4.146a
15.210a
22.32a
Values followed by the same letter (s) within column are not significantly different (P<0.05)
c. The effect of tested interaction
Regarding the effect of the interaction between the independent variable irrigation levels and the second one, i.e., foliar application treatments on the total yield and its components. The results of Table (5) reveal that most of the studied characters were significantly (p ≤ 0.05) affected. The significantly highest average values for number of tubers/plant, total yield /plant and total yield / fed. were recorded due to the treatments of water level 75% ETC with spraying potassium silicate 5cm3/l. With regard to average values of tuber fresh weight (g), the tabulated results appeared that, irrigation with water level of 75% ETC with spraying potassium silicate 5 cm3/l significantly; gave rise to the highest average values during the first season. While the tubers dry matter percentage was not significantly affected during both seasons. Similar trend, more or less, was reported by Abo-Sedera et al. (2004) on taro and Abo- El Maged et al. (2007) and El-Sharkawy and El-Zohiri (2007) on Jerusalem artichoke.
3. Tubers′ quality traits
a. The maineffect of irrigation level
As for the tested water irrigation levels, the results of Table (6) divulged that the tested tubers′ quality traits (N%, P%, K%, total carbohydrate% and inulin% tuber content) were significantly affected (p ≤ 0.05) with the different levels irrigation water during the both seasons. Such results in Table (6) illustrated that nitrogen, phosphorus andpotassium as well as inulin and total carbohydrate percentage in produced tuber were significantly (p ≤ 0.05) increased with increasing irrigation levels up to 100 % ETc compared with 70 or 50 % ETc during growing season. These findings could be attributed to increasing soil moisture of root zone, which leads to such increments in the concentration of macroelements. Increasing of nutrients solubility and their availability to be absorbed and uptaken by plant and in turn increase their accumulation in produced tubers. The obtained results are, more or less, in agreement with those reported by El- sharkawy and El-Zohiri(2007) and Abo-El Maged et al.(2007) on Jerusalem artichoke and Abo-Sedera et al.(2004) and El-Zohiri and Abd Elal (2014) on taro.
The main effect of foliar application
Results obtained in Table (6) indicate that the foliar applicants besides exhibited significant positive effects (p ≤ 0.05) on increasing the concentration of the estimated elements as N and K tubers contents during the two seasons. While, the phosphorus and inulin contents in Jerusalem artichoke tubers was not significantly (p > 0.05) affected during both seasons. Carbohydrate tubers content was positively affected by the four foliar applicants in the first season only. Generally, the maximum increments of nitrogen, phosphorus, potassium total carbohydrates and inulin percentage content were detected for the foliar application of potassium silicate at 5 cm3 /l and G.B. x P.S. foliar application during both seasons. However, this increment did not reach the level of statistical significant when compared with them except for phosphorus and inulin percentage contents during both season. Shaaban and Abou El-Nour (2014) reported that foliar fertilization of potassium silicate may be more beneficial for silica deposition in the required key points which keep very healthy hairy roots allowing better water, macro- and micronutrient absorption. In this regard, Bhattarai and Swarnima (2016) explained that sugar content in potato tubers increases with the addition of potassium element to a certain level, and then starts to decrease. Low doses of potassium convert starch into sugar and vice versa at high doses. Khan et al. (2010) pointed out that increasing the concentration of potassium element has a positive effect on increasing tubers content of both sugars and starch. The recorded results are similar, more or less, to those reported by Abo-El Maged et al.(2007) on Jerusalem artichoke and Sameh and Shama, (2019) on potato. Abd El-Baky et al. (2010), reported that total yield of sweet potato per plant and total yield per feddan declared a positive response to supply with potassium. The promising effects of four foliar spraying applications with potassium silicate, glycine betain, interaction G.B. x P.S. and control (without spraying) on Jerusalem artichoke increasing yield/fed and its component characters, and these finding might be attributed to its positive effects on enhancing vegetative growth traits (Table 5) and the role of potassium as a macroelement in assimilation and translocation of plant synthetic assimilated molecules from the organs of synthesis to the storage organs (tubers). This result is consistent with those of Soja et al., (1990); Mansour et al. (2001); Tawfik et al. (2003) and Abo-El Maged et al. (2007) in their study on Jerusalem artichokecrop.
C. The effect of the interactions
Results of Table (6) indicate the interaction between irrigation levels and foliar applications of glycine betaine, potassium silicate, G.B. x P.S. and control, had a significant (p ≤ 0.05) effect on tubers K content during both seasons. The remaining estimated elements N, P and carbohydrate contents in tubers were not significantly (p > 0.05) affected by this interaction during both seasons except inulin content during the first season only. Generally, the best results were achieved when irrigation water level was 75%ETC with spraying of potassium silicate at 5 cm3/l, followed by irrigations water level at 100% ETC, while the lowest average values were at irrigation water level of 50% ETC. It could be indicated that spraying the growing Jerusalem artichoke plants with potassium silicate solution at the rate of 5 cm3/l significantly (p ≤ 0.05) alleviated the adverse effects of decreasing irrigation water levels through improving the vegetative growth characters; resulting in increases in total tubers yield, and tubers′ quality characteristic
Table (6). Average values of Jerusalem artichoke tubers chemicals components as affected by irrigation levels and foliar application of glycine betaine, potassium silicate and their interaction during 2017 and 2018 seasons
Treatments
Season 2017
Season 2018
Irrigation levels
Foliar application
N%
P%
K%
Total carbohydrates %
Inulin (%)
N%
P%
K%
Total carbohydrates %
Inulin
(%)
100% ETc
control
1.622a
0.213a
2.341e
59.54a
17.22a
1.541a
0.205a
2.331f
58.31a
20.14c
G.B. 5cm3/l
1.736a
0.275a
2.670g
56.41a
17.85a
1.687a
0.376a
2.154g
59.41a
20.56c
P.S. 200 mg/l
1.891a
0.307a
2.764h
62.12a
18.40a
1.932a
0.339a
2.631d
59.66a
21.78b
G.B. x P.S.
1.842a
0.241a
3.456e
60.20a
18.63a
1.684a
0.366a
2.632d
59.87a
21.22b
75% ETc
control
1.488a
0.292a
2.026d
54.22a
16.58a
1.890a
0.217a
2.548e
52.71a
19.54e
G.B. 5cm3/l
1.548a
0.244a
3.750c
58.63a
16.45a
1.871a
0.275a
3.451b
56.28a
22.14a
P.S 200 mg/l
1.893a
0.316a
4.691a
64.99a
17.66a
1.843a
0.325a
4.810a
59.63a
22.31a
G.B. x P.S.
1.365a
0.238a
4.573a
57.36a
17.56a
1.756a
0.345a
4.320a
53.69a
22.01a
50% ETc
control
1.122a
0.215a
2.077d
51.21a
15.78a
1.465a
0.267a
2.856c
53.69a
18.45f
G.B. 5cm3/l
1.045a
0.206a
2.522f
52.12a
16.32a
1.590a
0.268a
2.104g
54.21a
18.54f
PS 200 mg/l
1.225a
0.245a
3.448c
53.25a
16.54a
1.690a
0.298a
3.156b
56.32a
19.03e
GB x PS
1.258a
0.285a
3.821c
54.12a
16.84a
1.554a
0.264a
2.876c
55.41a
20.56c
Irrigations levels
100% ETc
1.961a
0.324a
4.014a
64.23a
20.02a
1.514a
0.248a
4.247a
59.33a
22.61a
75% ETc
1.782b
0.307b
3.226b
62.54b
19.22b
1.357b
0.217b
3.661b
56.87b
22.04b
50% ETc
1.325c
0.259c
2.451c
60.48c
18.11c
1.265c
0.186c
3.098c
51.63c
20.31c
Foliar application
control
1.461c
0.315a
3.487d
55.23a
17.22a
1.870b
0.26a
2.960c
58.65c
21.36a
G.B. (5cm3/l)
1.693b
0.335a
3.023c
54.12a
18.65a
1.638b
0.28a
3.126b
59.89b
21.42a
P.S. (200 mg/l)
1.846a
0.365a
4.221a
59.78a
19.22a
2.014a
0.31a
4.235a
62.55a
21.83a
G.B. x P.S.
1.698b
0.354a
4.012b
60.02a
18.96a
2.331a
0.32a
4.215a
59.25b
21.65a
Values followed by the same letter (s) within column are not significantly different (P<0.05)
4. Water use efficiency
Irrigation water use efficiency is defined as marketable yield per unit of irrigation water applied of growing plants, and is expressed as kg / m3. Results of Table (7) express that the estimated 100% ETc values were 998 and 965 mm in 2017 and 2018, respectively. The water consumptive use (CU) values were 4193 and 4056 m3 fed−1 while the irrigation requirement (IR) were 5426 and 5249 m3 fed−1; during the two growth seasons of 2017 and 2018, respectively (the application efficiency for drip irrigation equal 85% and the leaching fraction was considered as 10% of water requirement).
Table (7). Consumptive water use efficiency (CWUE) and irrigation water use efficiency (IWUE) by Jerusalem artichoke plant at 2017 and 2018 seasons
Treatment
Tuber yield (kg/fed)
Crop water consumptive use, CU (m3/fed)
Consumptive water use efficiency, CWUE (kg/m3)
Irrigation requirement, IR (m3/fed)
Irrigation water use efficiency, IWUE (kg/m3)
Tuber yield (kg/fed
Crop water consumptive use, CU (m3/fed)
Consumptive water use efficiency, CWUE (kg/m3)
Irrigation requirement, IR (m3/fed)
Irrigation water use efficiency, IWUE (kg/m3)
Irrigation
Season 2017
Season 2018
100% ETC
15456
4193
3.69
5480
2.82
16651
4056
4.11
5301
3.14
75% ETC
14253
3144
4.53
4110
3.47
16058
3042
5.28
3976
4.04
50% ETC
12687
2096
6.05
2740
4.63
13054
2028
6.44
2651
4.92
Irrigation levels
Foliar application
100% ETC
control
13690
4193
3.27
5480
2.50
13026
4056
3.21
5301
2.46
G.B
14813
4193
3.53
5480
2.70
14254
4056
3.51
5301
2.69
P.S
15023
4193
3.58
5480
2.74
14910
4056
3.68
5301
2.81
G.B x P.S
15014
4193
3.58
5480
2.74
15451
4056
3.81
5301
2.91
75% ETC
control
13012
3144
4.14
4110
3.17
13254
3042
4.36
3976
3.33
G.B
13456
3144
4.28
4110
3.27
13894
3042
4.57
3976
3.49
P.S
15253
3144
4.85
4110
3.71
15256
3042
5.02
3976
3.84
G.B x P.S
15362
3144
4.89
4110
3.74
14963
3042
4.92
3976
3.76
50% ETC
control
10456
2096
4.99
2740
3.82
11560
2028
5.70
2651
4.36
G.B
12145
2096
5.79
2740
4.43
12681
2028
6.25
2651
4.78
P.S
12365
2096
5.90
2740
4.51
12873
2028
6.35
2651
4.86
G.B x P.S
12045
2096
5.75
2740
4.40
12895
2028
6.36
2651
4.86
The results of Table (7) demonstrate the effects of irrigation water regime and foliar antitranspirants on the irrigation water use efficiency. Irrigation water use efficiency was significantly decreased when plants were irrigated with 100% and 75% ETc compared to 50% ETc both seasons. Foliar antitranspirants application caused an increase in irrigation efficiency; never the less, potassium silicate was more effective than glycine betaine especially at 50% ETC treatment. Karam et al. (2002) found the impact of deficit irrigation regimes on lettuce yield and water savings. They illustrate that water stress caused by the deficit irrigation; significantly reduced leaf number, leaf area index and dry matter accumulation. They also observed that applying 80 and 60% of ETC reduced final fresh weight by 20% to 30% with comparison to the control treatment irrigated at 100% of ETC. Bozkurt et al. (2009) reported that water deficit produced significant effect on yield and yield components except for plant dry weight.
Irrigation treatments affected significantly both the CWUE and IWUE during the two growth seasons. Under water stress, water was used efficiently more than normal irrigation. The higher values of water use efficiency observed under water stress treatment as compared to regular irrigation; was mainly due to less water applied for these treatments and the high obtained grain yield. These results are in agreement, more or less, with those reported by Mansour et al. (2001) and Bozkurt et al. (2009). Zhang et al. (2004) found that it is feasible to reduce irrigation amount in a certain growing stage of plant to maximize the irrigation water productivity.
Conclusion
An experimental investigation for two years was conducted to evaluate the response of drip irrigated Jerusalem artichoke to water stress. Increasing the irrigation water to 100%; increased the plant growth, nutrients uptake, and biological yield of plant. The tuber yield of Jerusalem artichoke plants irrigated with 75% of water requirements was lower by about 8% than that received 100% of water requirements. Irrigation Jerusalem artichoke by 100% of water requirements; increased the vegetative growth and lead to a slightly increasing in the tuber yield. Under drip irrigation system Jerusalem artichoke plants can be irrigated by only 75% of water requirements without any loss in the tuber yield.
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