Induced variations by gamma radiation and EMS on the agronomic traits, essential oil yield with its quality and their exploitation in Java citronella (Cymbopogon winterianus Jowitt)

Abstract

Purpose

The slips of Cymbopogon winterianus (Java citronella) are used to propagate this industrially important crop. It does not have a mating system that allows it to create new variability or develop superior progenies, which could be addressed by using induced mutation caused by physical or chemical agents. Physical treatments, rather than chemical treatments, are believed to be the most incredible alternative for mutation breeding. As a result, this study aims to assess the effects of gamma radiation and EMS treatment on the development of better C. winterianus progenies.

Materials and methods

The three superior lines, i.e. JC-62 (IC-0627007), JC-55 (IC-0627000), and JC-71 (IC-0627018) based on high herbage, essential oil yield and citronellal content were selected through clonal selection during three-year evaluation. These were then irradiated with ⁶⁰Co gamma rays (50 Gy, 100 Gy, 150 Gy, 200 Gy, 250 Gy, and 300 Gy) and treated with EMS dose (0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 and 1%) separately. Ten plants of each dose were mutated and planted in the experimental field to obtain the MV₂ progenies. After 4 months, the plants were harvested, and the slips were prepared and planted to get the MV₃ and subsequently MV₄ progenies. All morphological and essential oil data have been recorded and analyzed statistically. The essential oil was extracted through the Clevenger apparatus for all the progenies, followed by GC and GC-MS analysis.

Results

The morpho-chemical study of the 112 healthy mutants has led to the identification of six superior progenies in MV₄ progenies, M17, M63, M77, M179, M233, and M392. In terms of the economic yield, it was observed that mutant M77 treated with 0.20% EMS dose increased the herbage yield and citronellal content tremendously. In contrast, the progeny M17 irradiated with γ-100Gy increased essential oil yield from 1.32% to 1.50%. The EMS treatment at 0.10% and 0.20% doses showed an increasing trend in plant height, leaf length, tillers/bush, leaves/bush, herbage yield, and citronellal content compared to the base variety. The LD₅₀ value of C. winterianus for gamma radiation and EMS treatment was averaged at 173 Gy and 0.72%, respectively.

Conclusion

In C. winterianus, both gamma rays and EMS treatment successfully created superior progenies with desired characteristics. The 0.20 percent EMS treatment significantly improved economic features, including herbage yield and citronellal content. Simultaneously, gamma radiation at 100 Gy produced the highest essential oil yield, which is a highly desirable characteristic in C. winterianus breeding.

Keywords:

• Cobalt⁶⁰
• C. winterianus
• EMS
• essential oil
• gamma radiation
• mutation breeding

Acknowledgements

The authors are thankful to the Director, CSIR-NEIST, Jorhat, India for providing the necessary lab facilities and experimental field for smooth conducting of the experiment. We further acknowledge CSIR for funding in the form of network project Aroma Mission (HCP-007) as well as SERB (YSS/2014/000314).

Disclosure statement

The authors declare no conflict of interest.

Additional information

Funding

This work was supported by the Council of Scientific and Industrial Research; Science and Engineering Research Board.

Notes on contributors

Sunita Munda

Sunita Munda, PhD, is a Senior Project Associate at CSIR-NEIST, Jorhat, Assam, India. She has published 25 research papers and one book chapter. Her area of research includes- plant biotechnology, molecular biology, plant selection and mutation breeding.

Twahira Begum

Twahira Begum is a Research Scholar at CSIR-NEIST, Jorhat, Assam, India. She has published 21 research papers and three book chapters. Her area of research includes- plant breeding and genetics, molecular biology and plant biochemistry.

Ankita Gogoi

Ankita Gogoi is a Project Associate at CSIR-NEIST, Jorhat, Assam, India. Her area of interest includes molecular biology and genetics, plant breeding and research on chronic and acute toxicity.

Sudin Kr. Pandey

Sudin Kr. Pandey is a Research Scholar at CSIR-NEIST, Jorhat, Assam, India. He has published 34 research papers and areas of interest are medicinal and aromatic plants, plant breeding, mutation breeding and essential oil analysis.

Neelav Sarma

Neelav Sarma is a Research Scholar at CSIR-NEIST, Jorhat, Assam, India. He has published 19 research papers and areas of interest are plant breeding, biochemistry and microbiology.

Mohan Lal

Mohan Lal, PhD, is a Senior Scientist, Plant Breeding and Genetics at CSIR-NEIST, Jorhat, Assam, India. He has published more than 100 research articles, 36 book chapters and is a recipient of prestigious Dr E.R. Ekbote award. His area of expertise includes genetic improvement and varietal development of medicinal and aromatic plants.