Maize Dwarf Mosaic Virus: Effect of Time of Inoculation and Symptomatology on Performance of Sorghum (Sorghum bicolor). M. M. Jarjees, Department of Plant Pathology, Kansas State University, Manhattan 66506. J. K. Uyemoto, Department of Plant Pathology, Kansas State University, Manhattan 66506. Plant Dis. 67:488-489. Accepted for publication 26 October 1982. Copyright 1983 American Phytopathological Society. DOI: 10.1094/PD-67-488.

Two near-isogenic sorghum (Sorghum bicolor) inbreds, Combine Kafir 60 (CK60) and Kansas line 56 (KS56), were inoculated with maize dwarf mosaic virus strain A at three plant-growth stages. These inbreds differed in their responses to viral infections; under cool temperatures, CK60 developed tissue necrosis (red leaf disease) and KS56 a mosaic symptom. Results showed statistically significant yield losses with all virus treatments compared with their respective controls. At the earliest growth stage, yields of inoculated CK60 and KS56 were reduced 61 and 26%, respectively.