Pooja Negi is currently working as a scientific officer in the Nuclear Agriculture and Biotechnology Division at Bhabha Atomic Research Centre (BARC), Mumbai, India. She completed her post-graduation at the Dept. of plant molecular biology, University of Delhi in 2014, wherein she characterized the respective roles of novel ethylene response factors in tomato fruit ripening. During this time, she was the recipient of the Monsanto scholarship for academic merit and qualified for several research fellowships from major national funding agencies, including CSIR, DBT, ICMR and GATE. In 2015, she was awarded the Homi Bhabha gold medal for academic merit (Biosciences). Since joining BARC, she has actively worked towards the characterization of radiation-induced sugarcane mutants, at both lab and field levels. She is also interested in understanding the complex processes of crop-environment interaction and abiotic stress responses, in view of current and future climatic scenarios. Her continued interest in these areas has morphed into an ongoing doctoral thesis on investigating the inducible salt tolerance of a sugarcane mutant, through an omics-assisted approach. Till date, she has five peer-reviewed articles and two book-chapters to her credit.
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Sugarcane mutant M4209 retains heat-induced growth enhancement under salt stress
P. NEGI, M. PANDEY, R. K. PALADI, R. DEVARUMATH, V. T. BARVKAR, A. K. SRIVASTAVA
Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Mumbai-400085, India; Homi Bhabha National Institute, Mumbai-400094, India.
The progressively increasing climatic extremes are detrimental to global crop production and food security. Sugarcane (Saccharum officinarum L.) is an economically important long-duration crop, that faces continual climatic variations, including heat waves. Earlier, an inducible salt-tolerant mutant M4209 was developed from its elite parent cultivar Co 86032, using radiation-induced mutagenesis. In the present study, a comparative evaluation of M4209’s performance was conducted under the combined stress scenario of heat (42/28 °C; day/ night) and NaCl (200 mM) stress conditions (HS). Heat-stress increased plant biomass in both the genotypes; however, this beneficial impact was partially diminished in Co 86032 under HS conditions, which coincided with higher Na-accumulation. In addition, improved photosynthetic efficiency and preferential upregulation of photosynthesis-related genes, including SoRCA, SoRBSC and SoPSBS, was observed in M4209 relative to Co 86032, under all stress conditions. LC-MS based metabolome profiling indicated active metabolic reprogramming in M4209 compared with Co 86032 under HS, with greater percentage of shared metabolites with heat stress. Under HS condition, M4209’s novel signature consisted of both shared (e.g. chlorogenic acid) and specific (alpha-linolenic acid) metabolites, highlighting the role of antioxidants. Taken together, M4209’s physio-biochemical adaptations and metabolic reprogramming facilitate its superior growth and vigor under combined stress.