ROLE OF DEFENCE RELATED ENZYMES AND LIGNIN IN HOST RESISTANCE OF DURUM WHEAT CULTIVARS INFECTED BY Bipolaris sorokiniana

K. MALI¹, K.K. MIRAJKAR²*, S. BIRADAR³, S.R. PATIL^4
1Department of Biochemistry, College of Agriculture Sciences, University of Agricultural Sciences, Dharwad, 580 005, Karnataka, India
²Department of Biochemistry, College of Agriculture Sciences, University of Agricultural Sciences, Dharwad, 580 005, Karnataka, India
³Main Agricultural Research Station, University of Agricultural Sciences, Dharwad, 580 005, Karnataka, India
⁴Department of Biochemistry, College of Agriculture Sciences, University of Agricultural Sciences, Dharwad, 580 005, Karnataka, India
* Corresponding Author : mirajkarkk@uasd.in

Received : 24-01-2017     Accepted : 03-02-2017     Published : 18-02-2017
Volume : 9     Issue : 8       Pages : 3886 - 3890
Int J Agr Sci 9.8 (2017):3886-3890

Keywords : Bipolaris sorokiniana, Phenylalanine ammonia lyase, Peroxidase, Lignin, Phenols, Resistance
Academic Editor : Sandeep Kumar Sathua, Labani, Panda Parimal
Conflict of Interest : None declared
Acknowledgements/Funding : We thank Directorate of Research, University of Agricultural Sciences, Dharwad, India for the financial support, the fellowship and AICRP on wheat MARS, Dharwad for providing facilities for field experiments.We extend thanks to Dr. Ashalatha K V and Dr A R S Bhat for their guidance in statistical analysis.
Author Contribution : Kiran Kamalakar Mirajkar: Principle Investigator, who has conceptualized, designed the research programme and arranged for all the infrastructural facilities required for the research programme

Spot blotch, caused by Bipolaris sorokiniana, is a major disease of wheat in humid and warmer regions of the world. Host resistance is the most important trait in the host pathogen interaction. The aim of this research was to elucidate the potential biochemical parameters linked to Bipolaris resistance in the resistant NIDW295, PDW314 and susceptible Bijaga yellow, A-9-301 durum wheat cultivars. Analysis of defence enzymes like the phytochemical precursor enzyme, phenylalanine ammonia lyase (PAL), pathogenesis related proteins like, peroxidase (POX), along with the content of lignin, phenols and total chlorophyll presented significant differences between healthy and inoculated leaves (48 hrs post inoculation). Significant variations in PAL, POX activities, phenolic and lignin content were found between resistant and susceptible cultivars. Strong induction of PAL and POX activities were recorded in resistant cultivars NIDW295 (356.7%, 184.3%), PDW314 (253.6%, 156.6%) whereas minimal response was observed in the susceptible cultivars. The cell walls of NIDW295, PDW314 contained elevated levels of lignin and was observed to be more than 20 times higher with respect to Bijaga Yellow and A-9-301. The total phenolic content was highest for NIDW295, followed by PDW314, Bijaga Yellow and A-9-301. The reduction of total chlorophyll was significantly higher in susceptible genotypes in comparison to resistant genotypes. Our results suggest that these biochemical parameters (induction of PAL, POX enzyme activities, accumulation of lignin and phenols) are related to resistance to Bipolaris sorokiniana infection and indicate the perspective of use of these traits for the selection of resistant wheat genotypes.