Linkage between Maize Dwarf Mosaic Virus Resistance and Endosperm Color in Maize

Abstract

Maize dwarf mosaic is the most widespread virus disease of maize (Zea mays L.) in the USA. The objective of this study was to determine which, if any, of eight maize inbreds with resistance to maize dwarf mosaic virus strain A (MDMV‐A) had a gene or genes for resistance linked to the endosperm color gene (Y1) on Chromosome 6. Resistant inbreds with yellow endosperm AR234, Ark342, E663, N7B, SC54, SC278, and Tx5858 were crossed onto a susceptible inbred, Mp333, which has a white endosperm Resistant inbred KyBll0 with white endosperm was crossed onto the susceptible inbred CI21 that has yellow endosperm. The F2 kernels were separated for kernel color into dark yellow, light yellow, and white kernels. Plants from the dark yellow kernels had a significantly lower proportion of diseased to healthy plants than did plants from white kernels for all F2 populations involving resistant inbreds with yellow endosperm, indicating that each of these inbreds had a gene for resistance linked to Y1. The white inbred, KyB110, also has a gene for resistance linked to Y1 because the proportion of diseased to healthy plants was lower for plants from white kernels than for plants from dark yellow kernels. Resistance to MDMV‐A for the gene(s) linked to Y1 among the resistant parents seemed to be dominant to mostly dominant except for KyBll0. The data indicated that most of the resistant lines have additional genes for resistance to MDMV that are not linked to the Yl gene. However, crossovers between the gene for resistance to MDMV and the Yl gene and/or gene penetrance could have an effect on what conclusions can be made.