One of the biggest problems of modern world is agriculture. Population of the world is currently growing. Unevenly distributed population and increase in the number of large cities are just a couple of the causes of the world's problems with hunger and bad nutrition. That is one of the reasons why major companies are building skyscrapers where they will cultivate plants which are needed in daily nutrition. As there are so many people living in very small area, these plants need to be cultivated quickly. Plants can not increase their growth speed, so we wanted to find a solution. Genetic therapy was not considered as it is very expensive. We came up with an idea to treat seeds with non-thermal plasma, as it is very easy to produce it. We are participating in #scichallenge2017 in hope to contribute to the development of agricultural engineering with our work. Please like and share!

1. Magda Topić, Dominik Matišin, Filip Kusetić
Mihaela Marceljak Ilić, M.Sc.;Marko Movre, M.Sc.
XV. gimnazija, Zagreb
Project “The star is born”, Institute of Physics, Zagreb

2. Introduction
problems in the modern world:
• hunger and inefficient
agriculture
• increased need for food supplies
solutions:
• increase in the growth speed of
plants
• increase of the number of fruits
• vertical farming

3. Plasma
• electrically neutral, fourth state of matter; ionized gas
• thermal and nonthermal plasma
• nonthermal plasma - used in the research (atmospheric pressure, low
pressure)
• any plasma that is not in thermodynamic equilibrium
• made by high electric charge or strong lasers

4. Plasma agriculture
plasma is effective in various domains:
• sterilization, disinfection
• affecting the structure of large molecules
• surface modification for water uptake
• signaling
⟶ HYPOTHESIS: Plasma can enhance the growth speed of plants.

5. Plants
Garlic (Allium sativum L.)
• bulbous perennial herb
• tall, erect flowering stem
• pink or purple flowers
• garlic seeds - domestic from the
NorthWest region ofCroatia, Sveta
Nedelja
Parsley (Petroselenium crispum L.)
• flowering plant
• native to the central Mediterranean
region
• widely cultivated as a herb, a spice,
and a vegetable

6. How is all of that connected?
• seeds of garlic and parsley ⟶ treated in plasma ⟶ planted
• hydroponics; reverse osmosis (RO) treated water

8. Results
0
5
10
15
20
25
30
35
11 12 13 14 15 16 17 18
numberofplantswithtwoleaves
days
Parsley – growth of two leaves
control group treated
0
5
10
15
20
25
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
numberofgerminatedseeds
days
Parsley – germination
(12/28/2016 - 9 min, 50 seeds, 2nd box)
control group treated

9. treated with plasma
control group

10. Results
0
10
20
30
40
50
60
1 2 3 4 5 6 7 8 9
numberofgreminatedseeds
days
Garlic – germination, 2/14/2017
control group treated
plasma treated → not only germination delay, but rather inhibition!
low-pressure plasma – 12 mbar,
0.2 L/min He flow

11. 0
5
10
15
20
25
30
35
2 4 6 8
averagenumberofrootsperplant
days
Onion root growth in time
control group 3 min 6 min 9 min 12 min
Results

12. Contact angle
plasma affects the surface of the seed → contact angle of a water drop changes
• Tracker - video analysis and modeling tool;Open Source Physics
0.8 mm

13. Contact angle
PTFE – test non-treated
98 ± 5°
360 ± 42’
PTFE – test
plasma treated 10 min
83 ± 5°
290’

14. a mechanism for
contact angle
measurements

15. Contact angle
Static measurements
• the angle decreases with the
plasma treatment
• the effect fades with time

16. Allium test
• a standard test used in toxicology
and envioronmental monitoring
• study of chromosome damage
or disturbance of cell division
Onion (Allium cepa L.)
• vegetable; most widely cultivated species of the genus Allium
• treated in plasma
→ no chromosome damage was detected

17. Conclusions
• atmospheric pressure plasma does not enhance growth speed of garlic or
parsley; low pressure plasma has a similar effect
• it seems that the plant „remembers” that the seed was treated → bigger
leaves (parsley)
• contact angle decreases with the plasma treatment, but that effect fades
with time
• Allium test - there was no obvious damage on the chromosomes
• shorter treatments diminished growth speed of onion roots, longer ones
enhanced it (12 min)

18. Further developments of the project
• plasma activated water
• other plant species
• different plasma conditions

19. Literature
Cold-Plasma treatment of seeds to remove surface materials (J. C.Volin, F. S. Denes, R.A.Young,
S. Manolache)
Effects of Atmospheric-Pressure N2, He, Air and O2, Microplasmas on Mung Bean Seed
Germination and SeedlingGrowth (Re. Zhou, Ru. Zhou, X. Zhang, J. Zhuang, S.Yang, K. Bazaka, K.
Ostrikov)
Gas plasma treatment of plant seeds (S. A. Krapivina, A. K. Filippov,T. N. levitskaya, A. Bakhvalov)
Modification of Seed Germination Performance through Cold Plasma ChemistryTechnology (J. C.
Volin, F. S. Denes, R. A.Young, S. M.T. Park)
Non-Thermal PlasmaTreatment of Agricultural Seeds for Stimulation of Germination, Removal of
Surface Contamination and Other Benefits (L. K. Randeniya, G. J. J .B. de Groot)
Water uptake mechanism and germination of Erythrina velutina seeds treated with atmospheric
plasma (C. Alves Jr., J. O.Vitoriano, D. L. S. da Silva, M. L. Faras, N. B. L. Dantas)
Non-Thermal PlasmaTreatment of Agricultural Seeds for Stimulation of Germination, Removal of
Surface Contamination and Other Benefits (L. K. Randeniya, G. J. J .B. de Groot)

20. Thanks
Luka Čabraja, colleague
dr. sc. Slobodan Milošević, director of the Institute pf physics in Zagreb
Berti Erjavec, prof., associate from the Institute of physics in Zagreb
Dean Popović, prof., associate from the Institute of physics in Zagreb