Agrotechnology

Functional analysis of Cyanobacterial groEL2 in tobacco plants for abiotic stress tolerance

2^nd International Conference on Agricultural & Horticultural Sciences

Radisson Blu Plaza Hotel, Hyderabad, India February 03-05, 2014

Ch Jyotsna, Prakash J S S, Reddy Attipalli R, and Kirti P B

Posters: Agrotechnol

Abstract:

In order to improve the abiotic stress tolerance in plants, we attempted gene transfer methodology using molecular chaperone like groEL 2 from Synechocystis PCC6803 and chloroplast transit peptide (CTP) of the small subunit of the Rubisco complex from Brassica juncea . Transgenic tobacco plants were generated with and without chloroplast targeting of groEL2 and they were able to tolerate abiotic stresses induced by sodium chloride, mannitol, cadmium chloride, and methyl viologen. To better understand the role of chloroplast targeting of groEL 2 (CTP-groEL2) over the normal transgenic groEL 2 and the non transformed tobacco plants, we compared the performance by subjecting the plants to drought stress and measured their photosynthetic efficiency using Handy Pea. Seedling assays showed that CTP- groEL 2 plants exhibited enhanced tolerance to abiotic stresses. Damage caused by the induced stress was lower in CTP- groEL 2 expressing tobacco transgenic plants compared to the groEL 2 expressing transgenic plants and the wild type as assessed by their higher relative water content, higher total chlorophyll content, lower MDA, reduced super oxide and H 2 O 2 accumulation. Enhanced levels of different antioxidant enzymes and molecules were present in the CTP- groEL 2 plants when compared to the wild type under similar stress. Analysis of chlorophyll a fluorescence using specific energy fluxes, quantum yields and efficiencies along with performance index etc showed that CTP- groEL 2 plants tolerated drought conditions more efficiently, when compare to other plants. These attributes in transgenic tobacco ultimately prove the importance of chloroplast targeting of groEL 2 as a potential approach in alleviating abiotic stress tolerance.

Biography :

Ch Jyotsna is pursuing Ph.D. in Plant Biotechnology under the supervision of Prof P B Kirti from Department of Plant Sciences, University of Hyderabad, Hyderabad. She has completed masters degree in Environmental Biotechnology from Jawaharlal Nehru Technological University, Hyderabad, India.