Dissertation for Master's Degree
Agricultural Engineering-Horticultural Orientation (flowers and ornamental plants)
Abstract
Microwave or microwave It is a type of electromagnetic waves with a short wavelength and a very high number of oscillations (frequency) between 300 MHz and several GHz per second. In this research, 2M226 magnetron with a wavelength of 12 cm and 2.45 GHz frequency band radiation with a maximum output power of 1000 watts (W) and a radiation density of 341 kW/m was used as a source of microwave radiation. Licorice plant seeds were exposed to 100 and 500 watt microwaves with a maximum intensity of 4.2 kW/m3 and 321 kW/m3 for 0, 30, 60, and 90 seconds. The results showed that the application of microwaves increases the yield of seeds in the laboratory environment. Germination percentage, germination rate, root length, seedling total length, dry weight, seedling stand index and germination stress index increased significantly compared to the control. During the combined treatment including microwave power and duration, microwave treatment with 100 W power for 30 and 60 seconds showed better results than the control. Also, in the germinating seeds under the influence of microwaves, the amount of chlorophyll and the total content of photosynthetic pigments were significantly higher than the control. By increasing the duration and power of microwaves, the amount of proline and anthocyanin in both root and stem showed significant changes compared to the control.
Key words: microwaves, anthocyanin, proline, seed germination, photosynthetic pigments, sweet expression.
Introduction
Solar energy is one of the major sources of energy in the solar system. Every second, 2.4 million tons of the sun's mass is converted into energy. The temperature in the center of the sun is about 10 to 14 million degrees Celsius, which is spread from its surface with a heat of nearly 5600 degrees and in the form of electromagnetic waves. The earth is located at a distance of 150 million kilometers from the sun and it takes 8 minutes and 18 seconds for the sunlight to reach the earth. Therefore, the earth's share in receiving energy from the sun is a small amount of its total radiant energy. The origin of all the different forms of energy known on the planet includes (fossil fuels stored in the earth, wind energy, waterfalls, sea waves and) from the sun.
The earth is like a permanent magnet. The natural magnetic field of the Earth includes two main components in the range of 50 milliTesla (magnetic flux density) and several influential sub-compositions, including solar activities in the range of 0.03 milliTesla and atmospheric events in the range of 0.5 milliTesla.
, 1950). et al Bullard (
The strength and direction of the earth's magnetism (gravitation of the earth) is different in different places. On the surface of the earth, the vertical magnetic flux has the greatest strength in the axis of the earth's poles and is about 67 millitesla, and it is zero in the equator (latitude zone). The earth's poles are zero. All plants on the earth's surface are affected by electric and magnetic fields. The space between the earth's surface and the ionosphere acts as a conductor in an electric field that occurs at a very low frequency It is the natural induction of energy by lightning current. Williams (
) Visible or natural light belongs to a family of electromagnetic waves called electromagnetic spectrum (EM) Electro Magnetic. Natural light has important roles in the growth and survival of species in plant and animal ecosystems. Each member of the (EM) family is defined in a specific frequency or wavelength. Determining whether other members of the EM (EM) family, in addition to visible light, have an effect on plants and seeds has been the focus of many researchers.By using a favorable external electromagnetic field, activation of plant growth, especially seed germination, can be accelerated. However, achieving the mechanism of beneficial electromagnetic field effects on plants requires conducting various researches in controlled laboratory and farm conditions.) et al., 1988; Morar al., 1988 et ( Xiyao
1-2- Objective
1-2-1- General objective
In this research, the effects of microwave electromagnetic waves on licorice seeds will be investigated with the aim of increasing and improving the parameters of germination and growth, which in turn will improve the yield. and increases the quality of the plant's production materials.
In particular, an increase in seed germination is expected by changing the power and duration of using microwaves. For this purpose, microwaves were used to determine the best time and power effective on licorice seeds.
It was assumed that the parameters of seed germination using microwaves accelerate and increase.
1-2-2- partial objectives
It has been tried to study and evaluate the following objectives as partial objectives, and the results of the investigation are fully described in the next chapter.
a) Using physical methods to influence seed germination.
b) removing some barriers to germination, including seed dormancy.
c) investigating the scope of using the method of microwave radiation on the seeds of other plants.
d) investigating the effectiveness of this method in improving the increase in germination of non-standard seeds.
e) practical evaluation of the results of research on the propagation of ornamental plants using the method Using seeds.
f) producing seed bases for transplanting and multiplying plants.
g) Investigating the reduction of propagation costs due to increasing germination and reducing seed loss.
1-3 - Statement of the main research problem
Vegetative propagation (division of rhizome and root) is a limited, time-consuming and expensive method for propagating licorice, but this plant can also be propagated by seeds (Omid Begi, 2008).
The thick shell of licorice seeds prevents the penetration of weather and air inside the seed, preventing biochemical reactions and seed germination, which can be provided by using microwaves, the germination of licorice seeds and the possibility of timely reproduction on a large and commercial scale.
1-4- General
1-4-1- Electromagnetic waves
Electromagnetic waves or electromagnetic radiation based on wave theory is a type of wave that propagates in space and is made of electric and magnetic fields. In electromagnetic waves, electric and magnetic fields oscillate perpendicular to each other and propagate at the speed of light. Sometimes electromagnetic radiation is called light, but it should be noted that visible light is only a part of the range of electromagnetic waves. Electromagnetic waves have different types according to their frequency, which include: radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays. Electromagnetic waves are transverse waves (KC Kupta.