Initial Effects of Plasma Treatment on Maize Seeds: A Laboratory Study

Planning and modeling seed processing activities necessitate an understanding of the variances and relationships between the physical characteristics of seeds. The goal of this study is to establish the differences in fundamental physical features of selected maize seeds (Ganga Safed-2) and to find connections between these qualities following cold glow discharge plasma treatment. The effects of non-thermal plasma treatment of maize seeds on the rate of the seed’s physical properties like fresh weight, length, and dry weight have been investigated using a radiofrequency glow discharge plasma system. A cylindrical reactor is used for seed treatment. The treatment of maize seeds at 240 seconds and 30 watts has a great impact on their physical properties. We have used various types of gases for plasma treatment such as Nitrogen, Oxygen, Argon, hydrogen, and helium under atmospheric pressure and room temperature.


Introduction
Maize is a common grain crop that belongs to the Poaceae family.It is widely grown all over the world, not only because of its large yield but also for its excellent nutritional content.Maize is an important source of nutrition for around 70% of the nation's people, and most farmers cultivate it as a stand-alone crop on their farms [1].Traditional reproduction methods with long cycles and low productivity are used in the development of traditional crops, particularly vegetables.Physical technology is now widely employed in agriculture, particularly in the last decade.Plasma treatment of seeds is a novel technique that activates endogenous chemicals in seeds, allowing crops to enhance stress tolerance and productivity.Plasma seed treatment is the use of physical processes in agriculture, which is less expensive than using biological or chemical treatments to treat seeds and does not contaminate the environment.Plasma technology's implementation in agriculture offers a lot of potential.There are now various techniques that enhance crop establishment, including chemical sanitizers [2], organic and inorganic compounds, anti-biotics, biological control bacteria, and genetic alteration of seeds [3].This treatment, although, may not always be effective in lowering pathogens.They could also be hazardous or costly.As a result, a nontoxic, low-cost option for effective seed decontamination is needed.The use of plasma treatment to help seedlings germinate and survive is a novel strategy that has been proposed [4].Plasma pretreatment of seeds of essential crops is an excellent strategy for improving fertilization, root, and shoot development, according to preliminary research [5].Chemical, physical, and biological treatments are being developed to improve seed germination and development in the dynamic world [6].Physical invigoration treatments in seeds, on the other hand, can cause changes in seed shape, gene expression, and protein levels in the context of seed biotechnology [7].Increased germination and growth enhancement may arise from these physical alterations.The plasma treatments had strong antifungal and antibacterial effects, as well as enhanced water porosity via surface coat erosion and seedling development stimulation [8].The subsequent research, on the other hand, found that the seed's radicle length and weight had grown significantly [9].Plasma treatment has recently been shown to generate desirable traits in seeds by altering the surface of the seeds through surface functionalization by energetic particles and neutral radicals created inside the plasma [10].Experiments on the seeds of radishes, peas, tomatoes, carrots, and wheat in plasma agriculture have previously shown a significant increase in germination rate and seeding duration following plasma treatment [11].
The study looks at the use of low-temperature plasma as an alternative ecological technique for seed treatment, intending to overcome the shortcomings of the traditional methods and examine the physical features of seeds and determine what changes occur following plasma treatment of maize seeds and which radical is formed during plasma treatment.

Maize seeds
The seeds considered in this work were also unidirectional maize seeds in their natural state.Good-quality hybrid variety maize seeds (Ganga safed-2) were selected for the experimental purpose.The Ganga safed-2 variety seeds were purchased from Indore seed agency.Sound and healthy seeds were used for both laboratory experiments as well as field experiments.To these seeds, plasma treatment was given at a certain energy level and time.

Cold Glow Discharge Plasma
Shri Vaishnav Vidyapeeth Vishwavidyalaya, Indore's Center of Excellence for Plasma Research, developed, built, and deployed a system for creating glow-discharge plasma using RF and DC power supplies.In the Plasma system, a cylindrical stainless steel vacuum chamber (stainless steel material (SS304)) with a capacity of 33 liters, a height of 30cm, and a diameter of 36cm, as well as a cathode assembly electrode For RF electric discharge of gas, an RF power source with 13.56 MHz, 600 watts, and an automated matching network is used.Different gases are used to create glow-discharge plasma.The reactor creates a vacuum of 1x10 -3 mbar by a rotary pump.Gas supply lines are pumped across areas using a rotary pump.All inter-space lines to the gas cylinders, flow controllers, and vacuum chamber are separated by independent gas valves.A digital Pirani device is used to measure the vacuum within the chamber from atmospheric pressure to 10 -3 mbar, A mass flow controller is a device that regulates the rate of gas flow with precision [12].

Treatment of Maize Seeds
30 best Healthy seeds of Ganga Safed-2 were chosen by physical inspection.These seeds were kept in a stand and put between the electrodes within the vacuum chamber.The chamber was then pumped to a vacuum of 3x10 -2 millibars using a rotary pump.Then nitrogen gas was pumped into the chamber through a dosing valve at a flow rate of 100 mbar lit/s until the vacuum reached approximately 1x10 -1 millibars, and then RF power was delivered to the electrodes.After taking several shots with various parameters such as power, flow rate, and treatment time, we were able to optimize the process at 30 watts for 240 sec.At higher wattages above 50 watts and lower wattages below 30 watts, the seeds were not responding.At a range of 30 to 50 watts, the treatment time was also varying; for shorter and longer treatment durations, the seeds did not show any improvement.This process was repeated with a variety of gases, including oxygen, argon, hydrogen, and helium.After treatment, the gas flow was maintained for another 5 minutes to eliminate any undesirable reactive products.After being removed from the holder, the treated seeds were kept in a vacuum-sealed envelope for further analysis.

Seed Germination and Seedling Initial Growth
After taking out the seeds from the vacuum envelope, the seeds were disinfected with 0.1% Hgcl2.The seeds were kept for 10 minutes and then washed thoughtfully with distilled water.The seeds were spread in the Petri dishes covered with Whatman filter paper no.1 with 12 ml distilled water in it.An equal number of seeds were spread in every petri dish.(15 cm diameter Petri dishes were used).The seeds were kept in the seed germinator at 25°c.Maize seeds were grown for 8 days in laboratory conditions and 30 days in pots, after which data was collected.The seedling's length, fresh weight, and dry weight were measured.The controlled and treated seeds were given under similar lab conditions, and the temperature was maintained at room temperature.For each gas, 30 seeds were kept in a Petri dish with three sets and left untreated.-Fresh weight of maize plant after Thirty days 3. Result and discussion RF glow discharge plasma was used to treat maize seeds (Ganga Safed-2) using low-temperature plasma with oxygen, nitrogen, argon, helium, and hydrogen gases.The results were made into how the oxygen and nitrogen plasma treatment affected with the power of 30w and the time of 240s growth characteristics such as length, fresh weight, and dry weight in percentages of 28.10% and 23.90%, 38% and 34.75%, and dry weight marginally affected 10-25% as compared to control seeds.But if we discuss the treatment of argon plasma, it is a little bit higher, and the treatment of hydrogen and helium plasma is lower than the control.Talking about the 30-day data on germination length and fresh weight, it showed an increase of 27.90% and 31.40% in oxygen plasma treatment, 24.80% and 28.90% in nitrogen plasma treatment, 16.60% and 8.50% in argon plasma treatment, 7.60% and 4.50% in hydrogen plasma treatment, and 2.10% and 2.80% in helium plasma treatment as compared to control plants.

Conclusion
This study is unique in that it compares the effects of cold plasma discharges on maize seeds and shows how important it is to optimize process parameters for each kind of seed independently.We looked at how maize seedlings responded to plasma treatment in a surface discharge at standard temperature and pressure.For all treatment durations examined, it was discovered that the length, fresh weight, and dry weight of the oxygen and nitrogen plasma-treated samples were larger and heavier than those of the

Cold glow discharge plasma treatment with 30w and 240s
Oxygen Nitrogen Argon Hydrogen Helium Different Plasma Gases Plant weight % untreated seeds.It's concluded that the plasma treatment leads to an increase in the plant's length, fresh weight, and dry weight of seeds.The field data for two years will be examined at a later stage.

Figure 1 .
Figure 1.Experimental Setup for Producing Cold Glow Discharge Plasma