Abstract
Purpose: Environmental changes generate free radicals and reactive oxygen species (ROS) resulting in abiotic stress in plants. This causes alterations in germination, morphology, growth and development ultimately leading to yield loss. Gamma irradiation was used to experimentally induce oxidative damage in an important pulse crop Vigna radiata (L.) Wilczek or mung bean. Our research was aimed towards augmentation of oxidative stress tolerance through treatment with a group of aliphatic amines known as polyamines.
Materials and methods: We used sub-lethal doses of gamma irradiation to generate oxidative damage which was evaluated using Nitro blue tetrazolium (NBT) staining, total antioxidant activity, 1, 1-Diphenyl-2-picryl hydrazyl (DPPH) radical scavenging assay, proline content and lipid peroxidation. Changes in internal free polyamines and messenger ribonucleic acid (mRNA) expression of key rate-limiting S-adenosylmethionine decarboxylase (SAMDC) enzyme in polyamine biosynthetic pathway was studied using real-time polymerase chain reaction (PCR).
Results: We observed increased oxidative damage with higher irradiation dose which was partially alleviated by putrescine treatment. Internal levels of putrescine and spermidine increased with 1 mM (50 and 100 Gy) and 2 mM putrescine treatment. Expression of SAMDC also increased with putrescine treatment.
Conclusion: This study shows that treatment with putrescine can partially alleviate oxidative damage caused by gamma rays.
Acknowledgements
The first author is grateful to University Grants Commission, New Delhi, India, for awarding the Fellowship (UGC/542/Jr. fellow (Sc.)). The authors are thankful to UGC-DAE Consortium for Scientific research, Kolkata Centre, for providing with gamma irradiation facility.
Notes on contributors
Dr Mandar Sengupta works on the effects of gamma irradiation stress in plant system and its alleviation using polyamines. He is a Ph.D. from the University of Calcutta, Kolkata, India, under the guidance of Professor Sarmistha Raychaudhuri. He has published papers in international journals.
Professor Sarmistha Raychaudhuri has worked on the effect of gamma rays in plants. She has published several original research articles in reputed journals including International Journal of Radiation Biology with her doctoral students as co-authors. This article is a part of the Ph.D. thesis by Dr Mandar Sengupta.
Disclosure statement
The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.