Skip to main content
ARS Home » Pacific West Area » Riverside, California » National Clonal Germplasm Repository for Citrus » Research » Publications at this Location » Publication #186880

Title: DWEET MOTTLE VIRUS AND CITRUS LEAF BLOTCH VIRUS IN CALIFORNIA

Author
item Krueger, Robert
item BASH, J - UC RIVERSIDE, PLANT PATHO
item Rangel, Benjamin
item Lee, Richard

Submitted to: International Organization of Citrus Virologists Newsletter
Publication Type: Other
Publication Acceptance Date: 3/1/2005
Publication Date: 7/1/2005
Citation: Krueger, R., Bash, J.A., Rangel, B., Lee, R.F. 2005. Dweet mottle virus and citrus leaf virus in california. International Organization of Citrus Virologists Newsletter.

Interpretive Summary: Dweet Mottle Virus (DMV) of citrus was first reported in the early 1960s in California. There have been few reported incidences since the initial report. In the mid- to late-1990s, Spanish researchers at IVIA detected an apparently new virus of citrus that caused bud union incompatibilities in certain scion/rootstock combinations. This virus was given the name Citrus Leaf Blotch Virus (CLBV). Based upon the reaction in indicator plants, they postulated that CLBV was closely related to DMV. Later, sequencing of the two viruses showed over 95 % homology, confirming this speculation. A later report of the Spanish that CLBV is seed-transmitted caused a concern in the nursery industry. Consequently, we surveyed the two sources of pathogen-tested citrus propagative material in California, the Protected Collection of the Citrus Germplasm Repository and the Foundation Block of the Citrus Clonal Protection Program, for the presence of this virus. It was not detected in any trees tested. Furthermore, we have failed to detect it when surveying field trees exhibiting bud union abnormalities for the presence of specific pathogens. We therefore believe that this virus or viruses are present if at all, only at a low incidence in California.

Technical Abstract: Dweet Mottle Virus (DMV) of citrus was first reported in the early 1960s in California. There have been few reported incidences since the initial report. In the mid- to late-1990s, Spanish researchers at IVIA detected an apparently new virus of citrus that caused bud union incompatibilities in certain scion/rootstock combinations. This virus was given the name Citrus Leaf Blotch Virus (CLBV). Based upon the reaction in indicator plants, they postulated that CLBV was closely related to DMV. Later, sequencing of the two viruses showed over 95 % homology, confirming this speculation. A later report of the Spanish that CLBV is seed-transmitted caused a concern in the nursery industry. Consequently, we surveyed the two sources of pathogen-tested citrus propagative material in California, the Protected Collection of the Citrus Germplasm Repository and the Foundation Block of the Citrus Clonal Protection Program, for the presence of this virus. It was not detected in any trees tested. Furthermore, we have failed to detect it when surveying field trees exhibiting bud union abnormalities for the presence of specific pathogens. We therefore believe that this virus or viruses are present if at all, only at a low incidence in California.