TY  - BOOK
AU  - Philip S
AU  - Abraham
AU  - Elias R.S
AU  - Jacob C.K
AU  - Joseph A
AU  - Joseph K
TI  - In vitro evaluation of the antagonistic activity of endophytic bacteria against major leaf pathogens of Hevea Brasiliensis
PY  - 2013///
PB  - Rubber Science
KW  - Antagonists
KW  - Corynespora
KW  - Endophyte
KW  - Phytophthora meadii
N2  - Phytophthora meadii and Corynespora cassiicolo cause severe leaf infection leading to leaf fall in Hevea brasiliensis. At present, growers resort to spraying of chemical fungicides to control these pathogens in rubber plantations. Biocontrol measuresare not yet practised for the management of these diseases in rubber plantations as they were not proved effective. In this study, isolation and selection of endophytic bacteria were made from rubber that exhibit significant antifungal activity against these two fungal pathogens. A total 154 bacterial isolates were collected from leaves, petioles, barks and tender stem of three Hevea clones, viz. RRII 105, GT 1 RRIM 600. These isolates were screened for in vitro antagonistic activity against the two pathogens. Isolates showing more than 3cm inhibition zone on the growth of pathogens in dual culturing were selected. These antagonists produced antipathogenic volatile compound and siderophores. In vitro salicylic acid production by the antagonistic bacteria was also estimated. Seven isolates showing more antagonism and production of antifungal metabolites were selected for further studies. Bioassay using the ditached leaves of endophyte treated plants showed reduction in lesin size upon inoculation with the pathogens. The inoculated plants also showed increase in PR proteins - chitinase, peroxidase and phenylalanine ammonialyase activity that give systemic resistance to plants. Antagonistic isolates were identified as Bacillus spp. by 16S rDNA sequencing
ER  -