Assessment of gamma radiation through agro-morphological characters in camellia sinensis L. (O.) kuntze

Abstract

Purpose

To study the effects of gamma radiation on tea seed germination, morphological changes, and genetic variation by using gamma radiation.

Material and Method

Fresh Tea seed material were irradiated with twenty different doses of gamma radiation such as 0, 2, 4, 6, 8, 10, 15, 20, 25, 30, 40, 50, 60, 70, 80 90, 100, 200, 500 and 1000 Gy from Cobalt ⁶⁰Co source from Regional Nuclear Agriculture Research Center, Bidhan Chandra Krishi Viswavidyalaya (BCKV), West Bengal, in between 2019 and 2020.

Result and Conclusion

The growth behavior of tea seedling was recorded under varying levels of gamma radiation and its performance at nursery stages. It was observed seed irradiated with doses from 35 Gy to 100 Gy could germinate but could not survive beyond five (05) months. When treated with higher doses as 200 Gy, 500 Gy and 1000 Gy, no seed germination takes places due to possible damages occur in the DNA structure. Screening of growth characteristics of tea plant generally monitored by the characteristics like plant height, number of leaves, number of primary branches, base diameter, and total leaf area of plants and we found that these characteristics significantly increased with the progress of time and increasing levels of gamma radiation; however, the plant height showed decreasing trend with the increasing levels of gamma radiation, which could be due to the change in chromosomal structure and genetic alteration. After 90 weeks of planting, the plant height, no. of primary branches, the number of leaves, plant base diameter, and total leaf area per plant recorded were 36.42 cm, 1/plant, 7.11/plant, 0.62 c.m, 22.92 cm²/plant respectively under the radiation level 30 Gy, whereas the corresponding figures of the above parameters at the control treatment were 85.32 cm, 1/plant, 18.84/plant, 1.18 c.m and 26.68 cm²/plant, respectively. The total plant height, no. of primary branches, the number of leaves, plant base diameter, and total leaf area per plant were significantly influenced by the rising levels of gamma radiation (up to 100 Gy), finally, after 90 weeks of planting, the maximum no. of branching was observed in the treatment of 8 Gy, 10 Gy and 15 Gy respectively. The study reveals a hitherto open the possibility of using gamma radiation on tea plant for creation of variation in the tea seed planting materials. Further studies on mutation using tea planting materials would give an insight into its mutable gene behavior.

Keywords:

• Characteristics
• gamma radiation
• germination
• radiation
• seed
• tea
• variability

Acknowledgement

The authors wish to acknowledge and express our great appreciation to the Director of the Tocklai Tea Research Institute, Jorhat, Assam. The authors particularly thank Dr. Somnath Bhattacharya, Department of Genetics and Plant Breeding, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, West Bengal for providing radiation facilities. We owe our gratitude to Dr. J. G. Manjaya BRNS, DAE, Trombay, Mumbai for their assistance during the program. The author acknowledges the financial support from the Board of Research and Nuclear Science (BRNS), the Department of Atomic Energy (DAE), and the Government of India.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

Board of Research and Nuclear Science (BRNS), Department of Atomic Energy (DAE), Trombay, Mumbai, Government of India (GOI) (Sanction no.: 35/14/34/2018-BRNS).

Notes on contributors

Shobhit K. Singh

Shobhit Kumar Singh Ph.D (Ag.), is working as Scientist ‘C’ in the Plant Physiology and Breeding Department of Tocklai Tea Research Institute (TTRI), Jorhat, Assam- 785008.

Devajit Borthakur

Devajit Borthakur Ph.D is working as Visiting Scientist in the Plant Physiology and Breeding Department of Tocklai Tea Research Institute (TTRI), Jorhat, Assam- 785008.

Abhijit Tamuly

Abhijit Tamuly, M.Sc. is working as Senior Research Fellow (SRF) under the funded project by BRNS (Board of Research in Nuclear Science, Mumbai) in the Plant Physiology and Breeding Department of Tocklai Tea Research Institute (TTRI), Jorhat, Assam- 785008.

J. G. Manjaya

J. G. Manjaya Ph.D, is working as Scientific Officer 'G.' in Nuclear Agriculture & Biotechnology Division of Bhabha Atomic Research Center, Trombay Mumbai-400 085, India.

Pradeep K. Patel

Pradeep Kumar Patel Ph.D is working as Scientist ‘C’ in the Plant Physiology and Breeding Department of Tocklai Tea Research Institute (TTRI), Jorhat, Assam- 785008.

Boby Gogoi

Boby Gogoi Ph.D is working as Scientist ‘C’ in the Plant Physiology and Breeding Department of Tocklai Tea Research Institute (TTRI), Jorhat, Assam- 785008.

Santanu Sabhapondit

Santanu Sabhapondit Ph.D is working as Scientist ‘C’ in the Biochemistry Department, of Tocklai Tea Research Institute (TTRI), Jorhat, Assam- 785008.

Nabajyoti J. Neog

Nabajyoti Neog B.Sc. is working as the post of Senior Technical Officer in Plant Physiology and Breeding Department of Tocklai Tea Research Institute, Jorhat, Assam- 785008.

A. K. Barooah

Anoop Kumar Barooah Ph.D is the capacity of Director of Tocklai Tea Research Institute, Jorhat, Assam- 785008.