ABSTRACT Bande, M. R., Nester. S. E... Khayat. A., Smilanick, J. L.. Frederick, R. D.. and Schaad. N. W. 1999. Comparison of efi‘ects of acidic electrolyzed water and NaOCl on fluen'a indica telio. spore germìnation. Plant Dis. 83:627-632. Definitive identification of free teliospores of filletia indica. causal agent of Karnal bum of wheat. requines polymerase chain reamion (PCRHaased diagnostic tests. Since direct PCR am- plification from teliospores has not been reliable. teliospores first must be germinated in order to obtain adequate DNA. We have routinely surfaoe-sterilìzed teliospores for 2 min with 0.4% (vollvol) sodium hypochlorite (NaOCl) to stimulate germination and produce axenìc cultmes. However. we observed that some spores were killed even with a 2-min NaOCl treatment, the shonest feasible duration. Decreasing the NaOCl concentration in our study from 0.4% to 0.3 and 0.2%. nespectively. increased teliospore germination, but treatment times longer than 2 min still progressively reduced the germination percentages. In testing alternative methods, we found “acidic electrolyzed water” (AEW). generated by electmlysis of a weak solution of so- dium chloride, also surface-sterilized and increased the rate of T. indica teliospore germìnation. In a representative experiment comparing the two methods, NaOCl (0.4%) for 2 min and AEW for 30 min increased germination fmm 19% (oontnol) to 41 and 54%. respectively. by 7 days afier treatment. Because teliospones can be tneated with AEW for up to 2 h with little, ìf any. loss of viability. compared with l to 2 min for NaOCl. treatment with AEW has certaìn advan- tages over NaOCl far surface sterilizing and increasing germination of teliospones of suspect T. indica. Additional keywords: disinfestant, supemxidized water. surface sterilization