Journal of Plant Nutrition Seed Germination of Basil ...

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Seed Germination of Basil and Cress under NaCl and Boron Stress a

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M. Khayyat , F. Moradinezhad , N. Safari , S. F. Nazari , H. Saeb & A. Samadzadeh

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Department of Horticultural Science, College of Agriculture, University of Birjand, Birjand, Iran b

Department of Agronomy and Plant Breeding, College of Agriculture, University of Birjand, Birjand, Iran Accepted author version posted online: 27 May 2014.

To cite this article: M. Khayyat, F. Moradinezhad, N. Safari, S. F. Nazari, H. Saeb & A. Samadzadeh (2014): Seed Germination of Basil and Cress under NaCl and Boron Stress, Journal of Plant Nutrition, DOI: 10.1080/01904167.2014.920388 To link to this article: http://dx.doi.org/10.1080/01904167.2014.920388

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ACCEPTED MANUSCRIPT Seed Germination of Basil and Cress under NaCl and Boron Stress

M. Khayyat,1 F. Moradinezhad,1 N. Safari,1 S. F. Nazari,1 H. Saeb,1 and A. Samadzadeh2

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Department of Horticultural Science, College of Agriculture, University of Birjand, Birjand, Iran

Downloaded by [New York University] at 09:55 18 August 2014

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Department of Agronomy and Plant Breeding, College of Agriculture, University of Birjand, Birjand, Iran

Address correspondence to M. Khayyat, Email:[email protected]

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ABSTRACT

The present research was conducted to evaluate the effects of salinized water with boron and sodium chloride (NaCl) on seed germination of basil and Cress. Treatments were: boron solution


(25 and 50mM), NaCl solution (25 and 50mM) and distilled water as control. The highest germination percentage and mean daily germination of both plants were obtained in boron 25mM. The highest mean germination time of basil and the day of 50% emergence of basil and cress were found in boron 50mM. Radicle length of basil was reduced by increment of all salinity treatments; however, the highest cress radicle length was observed in 50 mM NaCl. It is concluded that these plants can tolerate salinized water during the germination stage to some extent, however, the cress show more tolerance to these salinities than basil.

Keywords: NaCl, boron, salinity, seed germination, Osimum basilicum, Lepidium sativum

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INTRODUCTION

Basil (Osimum basilicum L.) and Garden-cress (Lepidium sativum L.), belong to Lamiaceae and Brassicaceae families, respectively, and both are vegetables, use strongly as leafy salad and


green crops in Iran. Cress or garden-cress is rich in vitamins A and C, iron, and calcium, also contains arachidic, ascorbic, behenic, erucic, gadoleic, linoleic, miacin, palmitic, sinapic, stearic, and uric acids, carbohydrates, cellulose, fiber, riboflavin, beta-carotene, beta-sitosterol, thiamine, alpha-tocopherol, and d-sylose (Duke, 2001), and its seeds are frequently used medicinally in Asia (Morton, 1976). The essential oil, leaves, seeds, flowers, and roots of basil are used as medicine. Decoction of leaves is used to treat fever, asthma, earache, and ringworm, and it is considered to be digestive and tonic. Seeds are used to remove film and opacity from eyes. Infusion of plant is used to treat cepalalgia, gout, and halitosis (Duke and Ayensu, 1985), colds, headache, gastric pain, abdominal distention, indigestion, ententes, diarrhea, irregular menses, and rheumatoid arthritis, snake and insect bites, eczema, and dermatitis (Lin, 1998). Salinity is one of the most important limiting factors in production of horticultural crops, which affect the germination rate, percentage and seedling growth in different ways depending on the plant species (Murillo-Amador et al., 2000; Almansouri et al., 2001; El-Keblawy and AlRawai, 2005) and/or cultivars, which may lead to uneven stand establishment and reduced crop yields (Foolad and Lin, 1997). Naturally occurring salt stress is generally due to sodium chloride (NaCl) (Levitt, 1972). More than 900 million hectares of land world-wide, approximately 20% of the total agricultural land (FAO, 2007), are affected by salinity, accounting for more than 6% of

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ACCEPTED MANUSCRIPT the world’s total land area. Sodium chloride (NaCl) is the predominant salt causing salinization, and it is unsurprising that plants have evolved mechanisms to regulate its accumulation (Munns and Tester, 2008). Boron (B) toxicity also is an important disorder that can limit plant growth on soils of arid and semi-arid environments throughout the world (Nable et al., 1997). It has been recognized the boron toxicity as an important problem limiting crop production in low-rainfall,


highly alkaline and saline soils of Australia, Asia and Africa (Roessner et al., 2006). High concentrations of B may occur naturally in the soil or in groundwater, or be added to the soil from mining, fertilizers, or irrigation water. Of all the potential sources, irrigation water is the most important contributor to high levels of B in soils (Chauhan and Power, 1978). Seed germination is an important and vulnerable stage in the life cycle of terrestrial angiosperms and determines seedling establishment and plant growth. Despite the importance of seed germination under salt stress (Ungar, 1995), the mechanism (s) of salt tolerance in seeds is relatively poorly understood, especially when compared with the amount of information currently available about salt tolerance physiology and biochemistry in vegetative plants (Hester et al., 2001; Hu et al., 2005; Kanai et al., 2007; Khayyat et al., 2009). Salinity affects seed germination through osmotic effects (Bliss et al., 1986), ion toxicity (Hampson and Simpson, 1990) or combination of them (Huang and Redmann, 1995). In plants, salt stress causes reduced cell turgor and depressed rates of root and leaf elongation (Werner and Finkelstein, 1995; Fricke et al., 2006), showing the primary impact of salinity on water uptake. Furthermore, high intracellular concentrations of both sodium (Na+) and chloride (Cl-) ions can inhibit the metabolism of dividing and expanding cells (Neumann, 1997), retarding germination and even leading to seed death. Zahedi et al. (2011) reported that different salts had strong impact on seed germination of basil plants.

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ACCEPTED MANUSCRIPT However, there is no report about the effects of salinized water using boron on seed germination of basil and garden cress, and also using sodium chloride on seed germination of Garden cress. Thus, the present research was carried out to evaluate the effects of salinized water including sodium chloride or boron on seed germination of basil and Garden-cress plants under laboratory


conditions.

MATERIALS AND METHODS

Seed and Petri Dishes Preparation

This laboratory experiment was carried out using basil and Garden-cress seeds in the Department of Horticultural Science, University of Birjand, Iran, during December of 2011. Before starting the experiment, forty petri dishes were prepared and dipped in 70°C distilled-water for about 20 min. The dishes disinfected using spray of 25% ethyl alcohol. Fifty seeds from each species were placed in each petri dish (80 mm) over two filter papers. The dishes were moistened with 5 mL of distilled water (control) or with an equal quantity of the respective solution.

Treatments

The following treatments were used: A) water (H2O)- distilled water (control); B) boron solution [25 and 50 mM; electrical conductivity (EC)= 3.21 and 6.4 ds m-1, respectively]; C) sodium chloride solution (25 and 50 mM; EC= 2.65 and 5.3 ds m-1, respectively). The dishes were placed

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ACCEPTED MANUSCRIPT in an incubation chamber under dark, and temperature of 25 ±1°C. Distilled water or test solutions were added to each petri dish, during the experiment according to their water requirements. The experiment lasted for 23 days.


Measurement

Germination percentage (GP), mean daily germination (MDG) and mean germination time (MGT), the day of 50% emergence (G50) and radicle length (RL) were measured in this experiment. The GP was recorded every day, starting from the first day after the seeds were initially placed in the petri dishes. With appearance of cotyledons in each seedling, RL was recorded, then, the respective seedling was removed from the experiment. MDG was assessed using Hartmann et al. (1990) method: MDG=∑ (N1T1+N2T2+…+NxTx)/Total number of seeds germinated Where N values are the number of seeds germinated within consecutive intervals of time; T values indicate the time between the beginning of the test and the end of a particular interval or measurement. MGT was calculated based on Schelin et al. (2003) as followed: MGT= ∑ (fini)/N Where fi is day during germination period (between 0 and 25 day); ni is the number of germinated seeds per day and N is Sum of germinated seeds. G50 was calculated based on Heydecker and Wainwright (1976): G50= [(t2-t1) × 50% + (p2t1-p1t2)]/ (p2-p1)

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ACCEPTED MANUSCRIPT Where t1 is time at which the germination percentage is less than 50%; t2 is time at which the germination percentage is more than 50%; and p1 and p2 are the measurements of germination percentage occurring at t1 and t2, respectively. RL were measured using a ruler. The experiment was arranged in a completely randomized design with 5 treatments and 4 replications, each replication consisted of one petri dish and 50 seeds in each. Data were


analyzed using MSTAT-C software (Michigan State University, East Lansing, MI, USA). Means were separated with least significant difference (LSD) at 1% level of confidence.

RESULTS AND DISCUSSION

Application of boron solution in 25 mM significantly increased germination percentage of both plants, compared with control (data not shown). Using sodium chloride solution as irrigation water led to increment of germination percentage of basil, compared with control (Data not shown). Ramin (2005) reported that basil could be classified as moderately tolerant to salt stress during seed germination and seedling emergence. In comparison with other treatments; the lower level of NaCl solution reduced this variable on cress (data not shown). Figure 1 (1A and B) shows the polynomial relationship (R2=1) between boron and/or NaCl concentrations with germination percentage of both plants. However, cress plant showed more salinity tolerance during germination stage. There was a polynomial relationship between boron and/or NaCl levels with mean daily germination of both plants (Figure 2; R2=1). These data indicated that salinity conditions to some extent and species-dependent, increase germination of these seeds that was in agreement with Zhang et al. (2010), which found that under salt conditions seeds

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ACCEPTED MANUSCRIPT were able to germinate faster and to higher percentages, because of take both salt and water up rapidly. MGT significantly increased in both plants under boron treatments, in which the highest value was obtained by the higher level of boron (Data not shown). There was a linear relationship between boron concentration and mean germination time of both plants (Figure 3A; R2=0.90 and 0.82, respectively). Boron solution in both levels increased the day of 50%


emergence and reduced the radicle length in both plants, compared with control (data not shown). Figure 3B showed the polynomial relationship between NaCl concentrations and mean germination time of both plants (R2=1). Radicle length of basil (R2=0.92) and cress (R2=0.74) plants linearly reduced by increment of boron concentrations (Figure 4A). Increasing the NaCl concentrations led to linear increment and reduction of radicle length of cress (R2=0.91) and basil (R2=0.88), respectively (Figure 4B). In rice, wheat, and barley, salinity has been shown to negatively affect the rate of starch remobilization by causing a decrease in α-amylase activity (Lin and Kao, 1995; Almansouri et al., 2001; Zhang et al., 2010). Plants can be classified into two main groups based on their response to saline stress, salttolerant halophytes and salt-intolerant glycophytes. However, this classification is somewhat artificial as the implied discreteness of response does not exist in reality, with responses occurring along a gradient (Greenway and Munns, 1980). Salinity-induced reduction in the germination of halophytes is mainly due to osmotic effects only, whereas glycophytes are more likely to exhibit additional ion toxicity (Romo and Haferkamp, 1987; Dodd and Donovan, 1999). Furthermore, the seeds of salt-tolerant species tend to have lower osmotic potentials, allowing them to absorb water from the environment. This decrease in osmotic potential can be achieved in two ways: exclusion of salt from the cells while maintaining osmotic potential using organic

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ACCEPTED MANUSCRIPT solutes, or by allowing sodium (Na+) and chlorine (Cl-) to enter the cells and using them as osmolites while having mechanisms for mitigating the toxic effects of salt within the cell (Zhang et al., 2010). Data show the highest germination percentage of both plants by boron 25mM, although this value is not significantly different from control (Table 1). The highest mean daily germination of basil was obtained by the lower levels of both boron and NaCl salts, which was


not significant compared with control (Table 1). The highest value for mean daily germination of cress (Table 1) and the highest mean germination time of basil (Table 2) was found in boron 25mM and the higher level of boron treatments, respectively. The mean germination time for cress significantly increased under all levels of boron and also under lower levels of NaCl (Table 2). The day of 50% emergence for basil, significantly increased by 50 mM boron, compared with other treatments (Table 2). This variable for cress also increased by the application of the highest level of boron (Table 2), but there was not significant differences among control, NaCl concentrations and the lower level of boron (Table 2). The radicle length of basil significantly reduced under salinized solution, compared with control (Table 2). In comparison with control, the highest radicle length of cress was found under NaCl treatments (Table 2). Using salt as an osmoticum in saline environments appears to allow seeds to germinate more rapidly, and at lower osmotic potentials than they might otherwise be able to (Zhang et al., 2010). This may have functional ecological effects, increasing these plants’ ability to compete temporally with other species, germinating faster and shading seedlings, which do not germinate as rapidly (Zhang et al., 2010). Salt has been shown to be an order of magnitude metabolically ‘cheaper’ than sugars for generating osmotic potential in vegetative plants (Raven, 1985), and may be similarly used in

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ACCEPTED MANUSCRIPT seeds, provided toxicity issues can be resolved. In vegetative plant cells, toxicity is resolved by vacuolar compartmentalization (Qiu et al., 2007), and recent reports suggest that Na+ can be bound in starch granules (Kanai et al., 2007). In seeds, however, this compartmentalization would be energy intensive, while binding sodium to starch would prevent the starch from being used to provide energy for germination. Thus, it would seem metabolic tolerance to salt would be


more important in seeds than at other life stages, due to their limited carbohydrate reserves (Zhang et al., 2010). From the present results it is concluded that the cress is more tolerant to salt stress than basil. It is advised to study and find more tolerant vegetable plants for cultivation in areas where salinized water are used for irrigation.

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ACCEPTED MANUSCRIPT REFERENCES Almansouri, M., J.M. Kinet, S. Lutts. 2001. Effect of salt and osmotic stresses on germination in durum wheat (Triticum durum Desf.). Plant and Soil 231: 243-254. Bliss, R.D., K.A. Plattaloia, W.W. Thomson. 1986. Osmotic sensitivity in relation to salt sensitivity in germinating barley seeds. Plant Cell and Environment 9: 721–725.


Chauhan, R.P.S., and S.L. Power. 1978. Tolerance of wheat and pea to boron in irrigation water. Plant and Soil 50: 145–149. Dodd G.L., L.A. Donovan. 1999. Water potential and ionic effects on germination and seedling growth of two cold desert shrubs. American Journal of Botany 86: 1146–1153. Duke, J.A. 2001. Handbook of phytochemical constituents of GRAS herbs and other economic plants. CRC Press: Boca Raton, FL. Duke, J.A., and E.S. Ayensu. 1985. Medicinal plants of China. 2 vols. Reference Publications: Algonac, MI. El-Keblawy, A., A. Al-Rawai. 2005. Effects of salinity, temperature and light on germination of invasive Prosopis juliflora (Sw.) D.C. Journal of Arid Environment 61: 555-565. FAO. 2007. FAO Agristat, www.fao.org (accessed on 10 June 2010). Foolad, M.R. and G.Y. Lin, 1997. Genetic potential for salt tolerance during germination in Lycopersicon species. HortScience 32(2): 296-300. Fricke, W., G. Akhiyarova, W.X. Wei, E. Alexandersson, A. Miller, P.O. Kjellbom, A. Richardson, T. Wojciechowski, L. Schreiber, D. Veselov, G. Kudoyarova, V. Volkov. 2006. The short-term growth response to salt of the developing barley leaf. Journal of Experimental Botany 57: 1079–1095.

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ACCEPTED MANUSCRIPT Greenway, H., R. Munns. 1980. Mechanisms of salt tolerance in nonhalophytes. Annual Review of Plant Physiology and Plant Molecular Biology 31: 149–190. Hampson, C.R., G.M. Simpson. 1990. Effects of temperature, salt, and osmotic potential on early growth of wheat (Triticum aestivum). 1. Germination. Canadian Journal of Botany-Revue Canadienne De Botanique 68: 524–528.


Hartmann, H.T., D.E. Kester, Jr, F.T. Davies. 1990. Plant propagation, Principles and Practices. Prentice-Hall International, Inc.: Inglewood Cliffs. New Jersey, USA. Hester, M.W., I.A. Mendelssohn, K.L. McKee. 2001. Species and population variation to salinity stress in Panicum hemitomon, Spartina patens, and Spartina alterniflora: morphological and physiological constraints. Environmental and Experimental Botany 46: 277–297. Heydecker, W., H. Wainwright. 1976. More rapid uniform germination of Cyclamen persicum L. Scientia Horticulturae 5: 183–189. Hu, L., H. Lu, Q.L. Liu, X.M. Chen, X.N. Jiang. 2005. Overexpression of mtlD gene in transgenic Populus tomentosa improves salt tolerance through accumulation of mannitol. Tree Physiology 25: 1273–1281. Huang, J., R.E. Redmann. 1995. Salt tolerance of Hordeum and Brassica species during germination and early seedling growth. Canadian Journal of Plant Science 75: 815–819. Kanai, M., K. Higuchi, T. Hagihara, T. Konishi, T. Ishii, N. Fujita, Y. Nakamura, Y. Maeda, M. Yoshiba, T. Tadano. 2007. Common reed produces starch granules at the shoot base in response to salt stress. New Phytologist 176: 572–580.

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ACCEPTED MANUSCRIPT Khayyat, M., E. Tafazoli, S. Rajaee, M. Vazifeshenas, M.R. Mahmoodabadi, A. Sajjadinia. 2009. Effects of NaCl and supplementary potassium on gas exchange, ionic content, and growth of salt-stressed strawberry plants. Journal of Plant Nutrition 32: 907-918. Levitt, J., 1972. Salt and Ion Stresses. In: Physiological ecology: a series of monographs texts and treatises. Academic Press: London. pp: 489-530.


Lin, K. H. 1998. Chinese medicinal herbs of Taiwan. Vol. 3. How Xiong Di Publishing: Taipei, Taiwan. Lin, C.C., C.H. Kao. 1995. NaCl stress in rice seedlings – starch mobilization and the influence of gibberellic acid on seedling growth. Botanical Bulletin of Academia Sinica 36: 169–173. Morton, J. F. 1976. Herbs and spices. Golden Press: New York. Munns, R., M. Tester. 2008. Mechanisms of salinity tolerance. Annual Review of Plant Biology 59: 651–681. Murillo-Amador, B., E. Troyo-Dieguez, H.G. Jones, F. Ayala-Chairez, C.L. Tinoco-Ojanguren, A. Lopez-Cortes. 2000. Screening and classification of cowpea genotypes for salt tolerance during germination. Phyton-International Journal of Experimental Botany 67: 71-84. Nable, R.O., G.S. Banuelos, J.G. Paull. 1997. Boron toxicity. Plant and Soil 193: 181-198. Neumann, P. 1997. Salinity resistance and plant growth revisited. Plant Cell and Environment 20: 1193–1198. Qiu, N.W., M. Chen, J.R. Guo, H.Y. Bao, X.L. Ma, B.S. Wang. 2007. Coordinate up-regulation of V-H+-ATPase and vacuolar Na+/H+ antiporter as a response to NaCl treatment in a C-3 halophyte Suaeda salsa. Plant Science 172: 1218–1225.

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ACCEPTED MANUSCRIPT Ramin, A.A. 2005. Effects of salinity and temperature on germination and seedling establishment of sweet basil (Ocimum basilicum L.). Journal of Herbs, Spices and Medicinal Plants 11 (4): 81-89. Raven, J.A. 1985. Regulation of pH and generation of osmolarity in vascular plants – A cost– benefit analysis in relation to efficiency of use of energy, nitrogen and water. New


Phytologist 101: 25–77. Roessner, U., J.H. Patterson, M.G. Forbes, G.B. Fincher, P. Langridge, A. Bacic. 2006. An investigation of boron toxicity in barley using metabolomics. Plant Physiology 142: 10871101. Romo, J.T., M.R. Haferkamp. 1987. Effects of osmotic potential, potassium chloride and sodium chloride on germination of greasewood (Sarcobatus vermiculatus). Great Basin Naturalist 47: 110–116. Schelin, M., M. Tigabu, I. Eriksson, L. Swadago, and P.C. Oden. 2003. Effect of scarification, gibberllic acid and dry heat treatments on the germination of Balanties Egyptian seed from the Sudanian savanna in Burkina Faso. Seed Science and Technology 31: 605–617. Ungar, I.A. 1995. Seed germination and seed-bank ecology of halophytes. In: Kigel J, Galili G. eds. Seed development and germination. Marcel Dekker: New York, NY. 599–627. Werner, J.E., R.R. Finkelstein. 1995. Arabidopsis mutants with reduced response to NaCl and osmotic stress. Physiologia Plantarum 93: 659–666. Zahedi, S.M., M. Nabipour, M. Azizi, H. Gheisary, M. Jalali, Z. Amini. 2011. Effects of kinds of salt and its different levels on seed germination and growth of basil plants. World Applied Science Journal 15 (7): 1039-1045.

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ACCEPTED MANUSCRIPT Zhang, H., L.J. Irving, C. McGill, C. Matthew, D. Zhou, P. Kemp. 2010. The effects of salinity and osmotic stress on barley germination rate: sodium as an osmotic regulator. Annals of


Botany 106: 1027-1035.

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ACCEPTED MANUSCRIPT Table 1 Effects of boron and NaCl salinity on germination percentage and mean daily germination of Basil and Cress seeds Germination percentage (%) Mean daily germination Basil Cress Basil Cress Control (0mM) 83.00ab 98.50ab 3.75ab 4.42ab H3BO3 (25mM) 89.00a 100.00a 4.00a 4.50a H3BO3 (50mM) 81.00b 99.00ab 3.65b 4.45ab NaCl (25mM) 87.00ab 95.00c 3.92a 4.25c NaCl (50mM) 85.50ab 97.00bc 3.85ab 4.35bc Within each column, same letter indicates no significant difference between treatments at 1% Downloaded by [New York University] at 09:55 18 August 2014

Treatments

levels.

Table 2 Effects of boron and NaCl salinity on mean germination time, the day of 50% emergence and radicle length of Basil and Cress seeds Treatments

Mean germination time Basil 7.03b

Cress 3.94b

The day of 50% emergence Basil Cress 7.00b 3.25b

Radicle length (mm) Basil 22.85a

Cress 23.89b

Control (0mM) H3BO3 8.01b 5.33a 5.75b 4.00ab 3.69c 14.39c (25mM) H3BO3 11.35a 5.46a 22.00a 4.50a 3.84c 11.05c (50mM) NaCl 6.88b 4.85a 6.50b 4.00ab 22.24ab 25.08ab (25mM) NaCl 7.05b 4.12b 6.50b 4.00ab 19.52b 29.03a (50mM) Within each column, same letter indicates no significant difference between treatments at 1% levels.

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FIGURE 1 Effects of Boron (A) and NaCl (B) concentrations on germination percentage of Basil and Cress seeds.

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FIGURE 2 Effects of Boron (A) and NaCl (B) concentrations on mean daily germination of Basil and Cress seeds.

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FIGURE 3 Effects of Boron (A) and NaCl (B) concentrations on mean germination time of Basil and Cress seeds.

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FIGURE 4 Effects of Boron (A) and NaCl (B) concentrations on radicle length of Basil and Cress seeds.

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