Characterization of The Pathogen Associated With Gummosis Disease Of Guggal Commiphora Wightii

Abstract

Guggal (Commiphora wightii) is an endangered small tree, endemic to newlinewestern India. It yields a medicinally important oleo gum resin upon newlinetapping however, dies thereafter. Hence, involvement of pathogen to gum newlineoozing was investigated. A bacterium was found associated with the gum newlineoozing and plant death. Similar bacteria were isolated from tapped plants newlineat different parts of Gujarat. Physiological, biological and molecular newlinecharacterisation of these bacteria along with different reference bacteria newlinewas done. Forty-three bacterial isolates representing fourteen different newlineguggal tapping locations of Gujarat, India belonging to four major zones newlinewere studied. These were further compared with thirteen other closely newlinerelated bacteria isolated from different crops using different biochemical newlinetests, different carbohydrate and related compound utilization tests, total newlineprotein profiling by SDS-PAGE analysis, ITS PCR analysis and their RFLP newlinestudy, ISSR- and rep-PCR analyses. The isolates showed variability in newlinetheir pehentic characters like different biochemical tests, utilisation of newlinedifferent carbon sources, reaction to organic acids, etc. Among 166 newlinedifferent plant species inoculated, the guggal isolates showed restricted newlinepathogenicity only to four species belonging to Commiphora. SDS-PAGE newlineprotein profiling showed that isolates were more or less homogeneous newlinewith Jaccard s coefficient of 0.769. ITS and ITS-RFLP of the guggal newlinebacteria showed uniform banding pattern. Whereas, BOX , ERIC and newlineREP PCR detected variability within the isolates. ISSR PCR also detected newlinevariability within the guggal bacterial isolates; however, these were newlinehomogeneous compared to other reference strains. The results from newlinevariation martix analysis, principal component analysis and cluster newlineAbstract newlinePage | 2 newlineanalysis based on the band patterns of the isolates from SDS-PAGE, ITSPFLP, newlinerep- and -ISSR PCR experiments explained relationship among the newlineisolates. The isolates DXH-03 and DXL-01 were grouped together with newlinemaximum 96% similarity whereas DXR-01 and DXA-0