TheinteractionbetweenricehostanditspathogenXanthomonasoryzaepv.oryzae(Xoo)atcellularlevelwasstudiedbyusingaresistantsomaclonalmutantHX-3anditssusceptabledonorMinghui63.AfterinoculationwithXoostrainZhe173(Chinesepathotype|\).theactivityofsuperoxidedismutase(SOD)andperoxidase(POD)inthecallusofMinghui63wasincreaseddramatically,andtheactiveoxygen(O2^-)wasproducedatahigherrate;Meanwhile,thecallusgrewslowlywiththereductionofproteincontent.ComparedtotheactivityofSODandPOD.theproductionrateofO2^-andthefreshweightinHX-3callusvariedlittleaftertheinoculation.ItcouldbeproposedthatthereweregreatdifferencesbetweentheresistanceofHX-3andMighui63atcellularlevel.TherewasnodifferencedetectedconcerningresistancetobacterialleafblightinHX-3betweentheplantandthecallus.
