%0 Journal Article
%@ 0931-1785
%A Kishore, G K
%A Pande, S
%A Podile, A R
%D 2005
%F icrisat:3200
%I Blackwell Publishing
%J Journal of Phytopathology
%K Arachis hypogaea L., biological control, chitinolysis, peanut, Pseudomonas aeruginosa
%N 3
%P 169-173
%T Chitin-supplemented foliar application of Serratia marcescens GPS 5 improves control of late leaf spot disease of groundnut by activating defence-related enzymes  
%U http://oar.icrisat.org/3200/
%V 153
%X Chitinolytic Serratia marcescens GPS 5 and non-chitinolytic Pseudomonas aeruginosa GSE 18, with and without supplementation of chitin, were tested for their ability to activate defence-related enzymes in groundnut leaves. Thirty-day-old groundnut (cv. TMV 2) plants pretreated with GPS 5 and GSE 18 (with and without supplementation of 1% colloidal chitin) were challenge inoculated after 24 h with Phaeoisariopsis personata, the causal agent of late leaf spot (LLS) disease of groundnut. GPS 5 and GSE 18, applied as a prophylactic spray, reduced the lesion frequency by 23% and 67%, respectively, compared with control. Chitin supplementation had no effect on the control of LLS by GSE 18, unlike GPS 5, which upon chitin supplementation reduced the lesion frequency by 64%, compared with chitin alone. In a time course study the activities of chitinase, β-1,3- glucanase, peroxidase and phenylalanine ammonia lyase were determined for the different treatments. There was an enhanced activity of the four defence-related enzymes with all the bacterial treatments when compared with phosphate buffer and colloidal chitin-treated controls. In correlation to disease severity in bacterial treatments, chitin-supplemented GSE 18 was similar to GSE 18, whereas chitin-supplemented GPS 5 was much more effective than GPS 5, in activation of the defence-related enzymes. The high levels of enzyme activities following chitin-supplemented GPS 5 application continued up to the measured 13 days after pathogen inoculation