Distribution and Multiplication of Western Aster Yellows Mycoplasmalike Organisms inCatharanthus roseusas Determined by DNA Hybridization Analysis

Mycoplasmalike organism (MLO) specific DNA probes derived from chromosomal or plasmid DNA of the severe strain of western aster yellows MLO (SAY) were used to monitor the distribution and multiplication of MLOs in periwinkle plants infected with the SAY or dwarf strain (DAY) of the western AY MLO. Plants were graft-inoculated, and DNA was extracted from different regions of the inoculated plants over a 10-wk period. DNA samples were applied to nitrocellulose membranes and hybridized to cloned, 32 P-labeled, MLO-specific DNA probes (...)