Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: November 8, 1998
Publication Date: N/A
Technical Abstract: Transmission rates of MRDV to maize (Zea mays L.) kernels by a standard VPI protocol (a) averaged 44.8 +/- 18.7% and were considered too low and inconsistent for planned studies. This protocol involved soaking kernels 2 1/2 hrs in 30 C water, inoculation on one side of the embryo axis, and incubation of inoculated kernels at 30 C for 2 days on moistened paper towels in a covered Pyrex dish before planting them in soil. To increase transmission rates and consistency, protocol (a) was modified by accommodating the asynchronous germination process with a delay of 4-hr prior to VPI (d), inoculating both sides of the embryo axis to increase the frequency of inoculations of the vascular bundles (b), and maintaining soil temperatures at 30 C for 2 days to enhance seedling emergence (c). In each test of a protocol modification there were four replications of 50 seeds each. Average rates of transmission for protocol combinations (a+b), (a+b+c), and (a+b+d) were 70 +/- 7.0, 81 +/- 4.6, and 91 +/- 7.2%, respectively. The latter modified protocol (a+b+d) offered both adequately high and consistent transmission rates for the planned studies.