Infection biology and defence responses in sorghum against Colletotrichum sublineolum

Basavaraju, P. and Shetty, N. P. and Shetty, H. Shekar and Neergaard, E. De and Jorgensen, H. J. L. (2009) Infection biology and defence responses in sorghum against Colletotrichum sublineolum. JOURNAL OF APPLIED MICROBIOLOGY, 107 (2). pp. 404-415.

[img] Text (Full Text)
j.1365-2672.2009.04234.x.pdf - Published Version
Restricted to Registered users only

Download (553Kb) | Request a copy
Official URL: http://dx.doi.org/10.1111/j.1365-2672.2009.04234.x

Abstract

Aims: To investigate the infection biology of Colletotrichum sublineolum (isolate CP2126) and defence responses in leaves of resistant (SC146), intermediately resistant (SC326) and susceptible (BTx623) sorghum genotypes. Methods and Results: Infection biology and defence responses were studied quantitatively by light microscopy, H(2)O(2) accumulation by DAB staining and HRGP accumulation by immunological methods. Inhibition of conidial germination and appressorium formation may represent prepenetration defence responses on the leaf surface. Inducible defence responses in the resistant genotypes included decreases in formation of appressoria as well as accumulation of H(2)O(2), HRGPs and phytoalexins. Concomitant with these inducible responses, fungal growth was stopped during or just after penetration in genotypes SC146 and SC326. High levels of H(2)O(2) accumulating at late infection stages (5 days after inoculation) in the susceptible genotype BTx623 correlated with necrosis and tissue degeneration. Conclusions: The early accumulation of H(2)O(2) and HRGPs indicates roles in defence whereas the late accumulation in genotype BTx623 correlated with successful pathogenesis. Significance and Impact of the Study: The fact that there is a significant correlation between induced accumulation of H(2)O(2), papilla formation and cell wall cross-linking, as evidenced by HRGP accumulation, and cessation of pathogen growth in resistant genotypes may help exploit host resistance in sorghum.

Item Type: Article
Uncontrolled Keywords: Colletotrichum; hemibiotrophy; HRGPs; infection biology; reactive oxygen species; sorghum anthracnose; Sorghum bicolor
Subjects: Agriculture Biological Sciences > Biotechnology
University of Mysore > PG Campuses > Manasagangotri, Mysore > Agriculture Biological Sciences > Biotechnology
Divisions: PG Campuses > Manasagangotri, Mysore > Biotechnology
Depositing User: Users 1 not found.
Date Deposited: 01 Apr 2013 07:51
Last Modified: 07 Aug 2013 07:23
URI: http://eprints.uni-mysore.ac.in/id/eprint/2726

Actions (login required)

View Item View Item