Performance of crops growth under low frequency electric and magnetic fields

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PERFORMANCE OF CROPS GROWTH UNDER LOW FREQUENCY ELECTRIC AND MAGNETIC FIELDS

Ossama E. Gouda1, Ghada M. Amer2

1Faculty of engineering, Cairo University High Institute of Technology – Benha University

ABSRACT: The biological effects of extremely low frequency magnetic fields (ELF MFs) on living organisms have been explored in many studies, but few of them investigate the combination effect of both magnetic and electric fields act upon their growth. In this study, the biological effects of electric and magnetic field on the early growth of plants are presented using different beans. The electric and magnetic fields are produced using a specially-made test cell. The results indicate that the electric field has an enhancing effect on the early growth of the tested crops, however some morbid state phenomena were observed on some crops. Also, the effect and morbidity rate increases with electric field intensity.

1. INTRODUCTION

Human beings, animals, plants and our surrounding are under the effects of electromagnetic fields by the use and necessity of electrical current as a result of the development of industrialization and technology. Especially those who live near the electrical transformers or high voltage distribution lines electromagnetic fields are considered one kind of stresses which can affect by direct or indirect ways on human beings, animals and plants. Electromagnetic field, supplied by electricity systems is quite low frequency 50 HZ and can be effective at different intensity depending on the distance to the system and the power carried by the network [1]. It is known that biological systems give different biological responses to applications of electromagnetic fields at different frequencies and intensities [2]. Many researchers working in different fields such as biology, medicine and agriculture have been interested about the influences of electric and magnetic fields in exchanges on the biological structures. In the last few years, some researchers show the effect of magnetic field with human body and biological tissues [3, 4]. However, the very few researches show the effect of electric and magnetic field with plant growing. This paper has

been proposed to study the effect of electric and magnetic fields on some crops growing. Some researchers showed that the low frequency electric field can inhibit the rate of growth of plant root [5]. Also it is observed that [5-7] electric field causes deformation inside grains through compression torsion of particular layers. In this experimental study uniform field is used. Exposure of seeds to magnetic field for a short time was found to help in accelerated sprouting and growth of the seedlings. Such plants also showed deeper roots as well as more vigorous growth compared to those, which have grown out of the untreated seeds. Electric field treatment of seeds leads to acceleration of plants growth and root development [5–10]. The electric field exposure increases germination of seeds and improves their quality. The growth of wheat and corn plantlets in an electric magnetic field was stimulated by means of different exposure protocols [10]. Having in mind the possible application of the magnetic and electric field treatment in agricultural practice and so can be used in bio-foul industries.

2. EXPERIMENTAL SETUP 2.1 Test Cell and Test Arrangement

The purpose of this study is mainly to assess the influence on the early growth of crops exposed to electric and magnetic fields. The test cell design in this experiment is consists of two plates of copper one is fixed and other is movable the maximum distance between the two plates is 50 cm, the test arrangements shown in Fig.1. Two sides of cell are made from wood and other parallel sides are made from fibber.

Fig. 1 Test arrangements

Auto transformer

Supply 50 Hz 220 V

Test cell

µA

Variable resistanc

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The cell is energized from the supply through autotransformer a variable resistance is connected with the copper plates to control the magnetic field. The electric field strength is controlled by varying the distance between the two copper plates. The current flow through the test cell plates is 16 A. Timer is used to control the energized time of testing cell. A group of seeds are taken as control group and other groups are exposed to electrical and magnetic fields to study the effect of EMF on them.

2.2 Exposure Electric Fields

The exposed group to electrical and magnetic fields and the control group are put in the same laboratory area to be on the same environmental parameters. The exposed groups inside the test cell are exposed to the electrical and magnetic fields for about eighteen hours every day. The variable resistance is fixed to feed the cell by a current of 16 A. The exposed groups of the seeds are put inside test cell between two copper plates under the effect of electrical and magnetic fields .The electric field is calculated from the following relation: E= V/ (d*ζ) (1) Where E is the electric field (V/m), V is the supply voltage (volt), ζ is the field utilization factor taken as and d is the distance between the

cell plates (m). The electric field inside the test cell is varied between 1, 1.375 and 1.625 kV/m. The details of magnetic field calculations are given in appendix I. Its calculated value inside the cell is 2.66 A/m.

2.3 Crops under Tests

The corn, wheat, Soya, chick-pea and Fenugreek seeds are used as the test material subject in this study, dishes with cotton pads were used as germinators. Two groups of tests (one under electric and magnetic field, and the other under electric field) are implemented. In each test, seeds of the same weight and similar appearance are selected, and separated into four dishes two plastic and two aluminum, divided them to two groups each group contains one plastic dish and one aluminum dish one group is exposed to field in the test cell (exposed group) and the other is out the cell in the same environmental condition (control group). All groups are fertilized with distilled

water at room temperature. The environmental conditions such as temperature, humidity and illumination of all groups are maintained. Finally the samples under testing can be classified as following: • Group 1: is the control samples dish. • Group 2: is the exposed samples to EMF in

plastic dish • Group 3: is the exposed samples to EMF in

aluminium dish • Group 4: is the exposed samples to electric

field= 1.625 kV/m in plastic dish. • Group 5: is the exposed samples to electric

field= 1.625 kV/m in aluminium dish. • Group 6: is the exposed samples to electric

field= 1 kV/m in plastic dish. • Group 7: is the exposed samples to electric

field= 1 kV/m in aluminium dish. • Group 8: is the exposed samples to electric

field= 1.25 kV/m in plastic dish. • Group 9: is the exposed samples to electric

field= 1.25 kV/m in aluminium dish. • Group 10: is the exposed samples to electric

field= 2.5 kV/m in plastic dish. • Group 11: is the exposed samples to electric

field= 2.5 kV/m in aluminium dish.

3. EXPERIMENTAL RESULTS AND ANALYSIS 3.1 Effect of Combined Electric and

Magnetic Field on Seeds Germination

Corn and wheat seeds are put in four dishes two plastic and two aluminum, the seeds are divided to two groups each group contains one plastic dish and one aluminum dish one group is exposed to field in the test cell (exposed group) and one is out the cell in the same environmental condition (control group). The distance between the two plates in the test cell is controlled to give electric field 1.625 kV/m. In the first stage the wheat and corn seeds are exposed to electric and magnetic field for 7 days, with electric field E=1.6253 kV/m and magnetic field intensity 2.66 A/m. Then new seeds of wheat and corn are exposed to electric field only with the values 1.625 kV/m for 7 days. In the two cases the wheat and corn seeds have germinated in all dishes but at the first sight we could observe significant differences in the

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average stem length value which are obtained by the relation as shown in Fig. 2. (2)

(a)

(b)

Fig. 2 Effect of electric and magnetic field in stem length (a) for corn seeds and (b) for wheat seeds.

From this figure it’s noticed that in the control dish corn 80% of seeds have germinated and maximum of the average stem length is 8 mm. In case of the exposed group to electric and magnetic field in plastic dish the measured average length is 16 mm. In aluminum dish 20 mm, in the case of group exposed to electric field only in plastic dish the measured average length was 137 mm and in aluminum dish 163 mm. Testing samples under electric field are shown in Fig 3. Table 1, Fig. 4 and Fig. 5 show the arithmetic standard deviations of the corn stems length which is calculated by the following relation:

(3)

From this analysis it is noticed that the test samples standard deviation for corn with electric and magnetic fields is higher than of the control group’s standard deviation. And the lengths of stems with applied electric field are longer than of those with electric and magnetic fields. In the two groups of tests the standard deviation in aluminum dish is higher than those in plastic dish. It’s noticed that the corn is more affected by the electric field than wheat.

Fig. 3 Effect of electric and magnetic fields on the

corn seeds Table 1 Results of statistical analysis of the height

of the corn & wheat stems. Standard deviation for corn stem growth

Group 1 Group 2 Group 3 Group 4 Group 5

Day2 0 0 0 0 0

Day 4 0 0 0 22.6275 18.3848

Day 6 2.82842 4.94975 7.07107 36.7696 34.6482

Day 8 2.82843 6.36396 7.77817 37.4767 49.4975

Standard deviation for wheat stem growth

Group 1 Group 2 Group 3 Group 4 Group 5

Day2 0.35355 0.35355 0.49498 3.53553 14.14214

Day 4 6.3952 11.5668 12.1324 23.2843 17.76955

Day 6 11.3137 16.5061 19.799 24.7487 19.79899

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Day 8 14.8492 22.6274 25.8701 217.2132 24.48528

3.2 Effect of Electric Field Intensities on Seeds Germination

In this experiment effect of electric field intensities on some crops germination such as corn, soya, chick-pea and Fenugreek seeds is studied. The distance between the two plates in the test cell is to obtained field intensities 1.625kV/m and 1 kV/m respectively .Fig. 6 shows the effect of the electric field intensity in the seeds germination. Table 2 shows the arithmetic standard deviations of the length of chick-pea stems for different field intensities. From Fig. 6 it’s noticed that the stem length increases with the increasing of the field intensities. Table 3 shows the results of statistical analysis of the height of the stem for chick-pea. The chick-pea seeds affect more than fenugreek and soya seeds by the change of electric field intensities as shown Fig. 6.

(a) Corn

(b) Wheat

Fig. 4 the standard deviation of the stem length for (a) corn and (b) wheat

Fig. 5 experimental results standard deviation, maximum, minimum and average for the stem

length for corn after 7 days for group 5

Table 3 Results of statistical analysis of the height of the stem for chick-pea

Standard deviation for chick-pea Group 1 Group 2 Group 3 Group 4 Group 5

Day2 2.121320 12.72792 9.899495 0.707107 2.121320 Day4 2.828421 4.242640 6.363961 3.535534 3.535544 Day6 4.242641 4.949747 5.656854 5.657 7.778175 Day8 2.1213203 2.82842 8.48524 7.0718 7.7782

(a)

(b)

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(c)

Fig. 6 Effect of electric field intensities on (a) Chick-pea, (b) Soya and (c) fenugreek seeds.

The field intensities are changed to 1.25, 1.625 and 2.5 kV/m by changing the distance between plates, wheat and corn seeds are tested. The average stem lengths are given in Fig. 7. In case of corn there is a big difference between the exposed seeds and unexposed seeds in the stem length. The ranges of the length of the exposed seeds are from 102 mm to 179mm but in control samples the maximum length of the stem is 8 mm, also the effect of using aluminum dish in the plant germination is also appear in all experimental results. For wheat and corn the length of the stem is increasing with increased the field intensities. The standard deviation for the stem length increase with increasing the electric field intensity. Fig. 8 shows the relation between the electric field and the average stem length of exposed to electric filed and recorded after two days, four days, six days and eight days from this group of curves it can be found that the average stem length of the eight days. Fig. 9 shows the comparison of the height of stems between with and without electric field. It is measured for 6 days after plant.

(a)

(b)

Fig. 7 Effect of electric field intensities on (a) Corn and (b) Wheat seeds.

Fig. 8 experimental results standard deviation, maximum, minimum and average for the stem

length for corn and wheat for group 11

3.3 Induced Current Induced current is recorded in tested seeds in aluminum dish. The current is measured by means of microampere . The measured current is ranged between 1 to 1.2 mA. In tested seeds in plastic dish circulating current lesser current is produced but not measured. Such these currents produce electrochemical attentions in components of the

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cell membrane surface. The current sends signal across the cell membrane barrier that produce alternations in intracellular biochemical and physiological functions [12]. Also it is noticed that this current increases the content of free radicals in seeds [5].

Fig. 9 Comparison of the height of stems between with and without electric field. It is measured for 6

days after plant.

4. CONCLOSION From the so many tests carried out on plants such as corn, heat, Soya, chick-pea and Fenugreek it is concluded that:

1. The induced current produces by low frequency magnetic and electric fields played an important role in the plant growth because this current send signals across the cell

membrane barrier that produce changes in biochemical and physiological functions. Therefore the magnetic and electric fields are considered pollutants to environment.

2. The plant growth length in samples under testing in the test cell depends on the field intensity, the combination of electric and magnetic fields and the growing medium of the plants if it is connected to earth or isolated.

3. The stems length of the exposed samples is longer than the samples that do not exposed to electric fields.

5. REFERNCE 1) V.Prasad Kodali, “Engineering

Electromagnetic Compatibility Principles, Measurements and Technologies”, IEEE PRESS, 1996, pp 11.

2) Charles Polk and Elliot Postow, “Handbook of Biological Effects of Electromagnetic Fields”; CRC Press; 1995

3) Noriyuki Hirota, Jun Nakagawa, Koichi Kitazawa “Effects of a magnetic field on the germination of plants”, Journal of applied physics, 1999, vol. 85, no 8, pp. 5717-5719.

4) Masafumi Muraji, Masao Nishimura, Wataru Tatebe and Tomoo Fujii “Effect of Alternating Magnetic Field on the Growth of the Primary Root of Corn”, IEEE Transactions on magnetic, 1992, vol. 28, no. 4, pp. 1996-2000.

5) Magda S. Hanafy & other “Effect of Low Frequency Electric Field on Growth Characteristics and Protein Molecular Structure of Wheat Plant” Romanian J. BIOPHYS., Vol. 16, No. 4, P. 253–271, BUCHAREST, 2006

6) L. Chao, D. R. Walker, Effect of a magnetic field on the germination of apple, apricot, and peach seeds, Hort. Sci., 2, 152–153, 1967.

7) G. H. Gubbels, Seedling growth and yield response of flax, buckwheat, sunflower and field pea after preceding magnetic treatment, Can. J. Plant Sci., 62, 61–64, 1982.

8) P. S. Phirke, S. P. Umbarkar, Influence of magnetic treatment of oilseed on yield and dry matter, PKV Research Journal, 22(1), 130–132, 1998.

9) A. Aladjadjiyan, Study on the effect of some physical factors on the biological habits of

Exposed group

Control group

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vegetable and other crops, DSc Thesis, Plovdiv, 2002.

10) A. Aladjadjiyan, Study of the influence of magnetic field on some biological characteristics of Zea mais, Journal of Central European Agriculture, 3(2), 89-94, 2002.

11) E. Martinez, M. V. Carbonell, M. Florez, Magnetic Stimulation of Initial Growth Stages of Wheat (Triticum aestivum L.), Electromagnetic Biology and Medicine, 21(2), 43–53, 2002.

12) Hanafy M.S., G. Husien, E. Abdelmo’ty, Effect of 50 Hz 6 kV/m electric field on the protein molecular structure and the growth

characteristics of the Broad bean (Vicia faba), Physics of the Alive, 2005, 13 (2), 41–54.

Appendix I

When current passes through plate or sheet Fig. A-1 can be obtained as the following:

(A/m) (1)

Where R the distance of direction from the current element to point at which dH is to be determined.

Fig A-1

Let sheet consist of infinite number of wires from (-0.3 to 0.3) in y direction

= (2)

From symmetric , Then

Let ,

Then ,

= , So

(3)

H is calculated by Eq. (4) from x=-0.15 to 0.15.

IdL (x, y, 0)

(0, 0, R 20

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