Agrotechnology

Impact of salicylic acid on salinity tolerance in field pea (Pisum sativum L.) through intensified antioxidant defense system, physiological and biochemical attributes

3^rd International Conference on Agriculture & Horticulture

October 27-29, 2014 Hyderabad International Convention Centre, India

A Hemantaranjan, R Singh, P K Patel, D K Yadav and A Nishant Bhanu

Scientific Tracks Abstracts: Agrotechnol

Abstract:

Salinity is one of the major abiotic stresses, and high concentrations of salts in irrigation water are a common environmental problem affecting plant growth, induces reduction in chlorophyll and photosynthetic activity and yield. Investigations were done in the last two years with a view to improve the antioxidant system and protect the biochemical attributes including nitrate reductase (NR) activity of two Field pea genotypes (DDR 61 and HUDP 15) by adopting the innovative seed priming and foliar applied techniques with salicylic acid (SA) under salinity stress conditions. For priming, seeds were soaked and hardened in aerated solutions of SA@ 1.5 mM. Salinity stress was imposed by NaCl @ 50, 100 and 150 mM with their corresponding EC 4.0, 8.2 and 10.6 dSm-1 respectively. Results showed that saline stress significantly reduced dry weight and water content of root and shoot. Photosynthetic rate and chlorophyll content were reduced by the NaCl while malondialdehyde (MDA) content and free proline content intensified. MDA, a decomposition product of polyunsaturated fatty acids, have been utilized as a biomarker for lipid peroxidation, hence estimated. SA priming and foliar application alleviated salt-induced oxidative stress by reducing malondialdehyde (MDA) content and increasing SOD activity. Interestingly, SA treated plants had greater shoot and root dry weights compared to untreated plants when exposed to salt stress. Result showed that 1.5mM SA application significantly increased photosynthetic rates, relative water content, total chlorophyll (a+b) content and leaf area in salt stressed plants. It was concluded that SA treatment could alleviate the adverse effects of salinity in pea (Pisum sativum L.) varieties. Further, nitrate reductase (NR) activity was significantly reduced under stress at the reproductive (i.e. post anthesis) stage of growth but was maintained higher in 1.5 mM SA treated plants up to the level of 100 mM NaCl in the genotypes studied. In addition to NR, membrane stability index (MSI) also decreased significantly under salinity stress. DDR 61 has the maximum MSI than HUDP 15. On the other hand, activities of antioxidant enzymes superoxide dismutase (SOD), ascorbate peroxidase (APX) and catalase (CAT) were up-regulated by salinity stress and further enhanced remarkably by 1.5 mM SA treatment. The response of SA (1.5 mM) was relatively more in DDR 61 than HUDP 15 genotype of field pea. As far as growth phase is concerned, the pre-anthesis phase was found to be more damaging than the post-anthesis phase of development. The results signify the role of SA in protecting vital physiological and biochemical attributes, on the one hand, and intensified antioxidant defense system, on the other hand. In addition, SA regulated plants through improved uptake of the micronutrient zinc, the significance of which is tremendous with a view to improved tolerance against salinity stress.

Biography :

A Hemantaranjan is Professor of Plant Physiology, Institute of Agricultural Sciences, Banaras Hindu University, India; Formerly University Head of the Department. He had done his PhD (1982) with First Class University career; 35 years Research and 30 years Post-graduate Teaching Experiences; Guided and produced 08 PhD and 37 MSc(Ag) Research Theses; Completed vital research projects. His research specializations are: Physiology of Plant Abiotic Stresses; Micronutrients; PGR in crop plants. He had published 105 international/national research and review papers - recurrently cited in world journals; Edited 21 Books. He is the recipient of UGC and CSIR prestigious Fellowships and Honours that also include "Research Scientist" Award. Also, he is Editor-in-Chief, International Treatise Series on Advances in Plant Physiology (edited over 15 Volumes, indexed in Current Book Contents, USA); Consulting Editor, Indian Journal of Plant Physiology (Springer), Legume Research; Member, Editorial Board, Indian Journal of Agricultural Research. He is delivering Invited/Guest Lectures for ICAR, UGC and USAID programmes; chairing technical sessions besides presenting research papers in scientific gatherings in India and abroad (UNM, Albuquerque, USA.; UHFI, Hungary; University of Wien, Austria etc. on special invitations). Additionally, he is Fellow, ISPP; Formerly Vice-President, Indian Society for Plant Physiology; Coordinator, UGC Refresher Courses (Agriculture). He is expert member: Selection Committees; Policy Planning Committee; Peer Reviewer - high impact international journals; Expert Member: ASRB (ICAR Selections; Examinations) and PhD theses evaluation of Indian Universities. He is the Organizing Secretary & Member of Committees, National & International Conferences respectively. Recently honoured with "Agricultural Excellence Award", MRF (2013); "Shiksha Rattan Award" (2010). Above all, Life Member of Indian and overseas Learned Bodies in Biology and Agriculture. Profound love for Nature!