VIEW ARTICLE

Vector Relations

Maize Bushy Stunt and Corn Stunt: A Comparison of Disease Symptoms, Pathogen Host Ranges, and Vectors. L. R. Nault, Professor, Department of Entomology, Ohio Agricultural Research and Development Center (OARDC), Wooster 44691; Phytopathology 70:659-662. Accepted for publication 10 December 1979. Copyright 1980 The American Phytopathological Society. DOI: 10.1094/Phyto-70-659.

The corn stunt spiroplasma (CSS) and maize bushy stunt mycoplasma (MBSM) are transmitted by Dalbulus maidis, D. elimatus, and Graminella nigrifrons; however, CSS is, but MBSM is not, transmitted by Exitianus exitiosus and Stirellus bicolor. The mean latent period for MBSM in D. maidis is 24.2 ± 1.9 days and for CSS 19.0 ± 2.0 days both at 27 ± 2 C. Teosinte (Zea mays mexicana) is a host for both CSS and MBSM, but Z. perennis and Z. diploperennis are hosts only for CSS. The mean latent period for MBSM in sweet corn is one-third to one-half the latent period for CSS. Maize bushy stunt mycoplasma causes more severe stunting and proliferation of axillary and basal shoots than does CSS. At high temperatures, CSS (but not MBSM) causes chlorotic spots and stripes on leaves. At low temperatures chlorotic spots and stripes may not develop, and CSS may produce symptoms resembling those caused by MBSM. Evidence suggests that MBSM is similar, if not identical, to the “Mesa Central” and “Louisiana” strains of corn stunt.