Submitted to: International Congress of Plant Pathology Abstracts and Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 8/9/1998
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: A disease of maize (Zea mays) and wheat (Triticum aestivum) with virus- like symptoms has been widespread in the High Plains of the central and western USA. The high plains pathogen (HPP) and wheat streak mosaic virus (WSMV) often are found together in the same plant. Both HPP and WSMV are transmitted by Aceria tosichella, but no pure culture of HPP has yet been continuously maintained by mite transmission. Mixed infections of WSMV and HPP in field grown and inoculated plants have confounded research efforts to determine the etiology and pathogenic effects of the disease. Vascular puncture inoculation (VPI) of seeds successfully transmitted maize viruses that were previously obligately transmitted by vectors. Recently we reported the transmission of HPP by VPI. The objective of this study was to improve the transmission rates of HPP with VPI and to isolate and maintain a pure culture of HPP. The isolate was confirmed as HPP by positive reactions in enzyme-linked immunosorbent assay (ELISA) and Western blot with antiserum to HPP and sodium dodecyl sulfate- polyacrylamide gel electrophoresis (SDS-PAGE) protein analysis for HPP. The absence of WSMV was confirmed by an absence of symptoms in rub- noculated maize (Oh28), wheat (var. Monon), and sorghum (Sorghum bicolor var. Atlas) and a negative reaction in ELISA and Western blot. High rates of transmission (90-100%) were achieved from extracts of infected, physiologically young tissues (ca 21 days after inoculation), from the supernatant or pellet of low and high speed differential centrifugation. Lower rates of transmission (ca 75%) were obtained from the pellets after CsSO4 equilibrium density-gradient centrifugation. A culture of HPP has been maintained free of WSMV contamination in over 25 serial transfers.