2011 Annual Report
1a.Objectives (from AD-416)
Investigate the cause(s) of collapse of managed European honey bees, Apis mellifera L. and find appropriate strategies to reduce colony loss. A USDA AFRI Coordinated Agricultural Project (CAP), granted to the University of Georgia, has two objectives that directly relate to the ARS interest:.
1)investigate the epidemiology and pathogenesis of Israeli Acute Paralysis Virus (IAPV), a virus that was found to be strongly associated with Colony Collapse Disorder (CCD, and develop RNA interference (RNAi) therapeutics for the treatment of the viral disease; and.
2)develop diagnostic tools for high-throughput detection and monitoring of honey bee diseases. The cooperator (representing a consortium of researchers on the funded AFRI grant) is interested in the synergistic interactions between honey bee microsproidian parasites, Nosema and viruses. ARS-BRL will work with the cooperators of the grant toward these common objectives.
1b.Approach (from AD-416)
We will use genomic approaches to:.
1)investigate the transmission routes of IAPV in honey bees;.
2)determine the spread and replication of IAPV infection under different host physiological conditions, develop the host genetic markers for diseases;.
3)develop RNAi-based l therapeutics for the treatment of viral diseases; and.
4)develop an economic screening tool and streamlined screening system for high-throughput detection and monitoring of honey bee diseases.
Honey bee colonies are suffering from numerous parasites and pathogens which are significant threats to the health and well-being of honey bees. The parent project objective directly addresses these threats. Among the pathogens attacking honey bees, viruses are probably the least understood because of the lack of information about the dynamics underlying viral disease outbreaks. In the past few years, honey bee colonies across the U.S, and around the world have been devastated by a poorly understood malady labeled Colony Collapse Disorder (CCD). Israeli Acute Paralysis Virus (IAPV) was identified to be strongly associated with CCD and is considered to be a significant marker for CCD. Therefore, gaining knowledge of the transmission and epidemiology of this virus is an integral part of the study of viral disease outbreaks and the development of environmentally friendly disease management strategies. In addition, it is important to develop genetic diagnostics tools for identifying the pathogens and defining disease threats to honey bees.
In FY 2011, progress was made in determining the role of the parasitic mite, Varroa, in IAPV transmission and activation in honey bees, understanding virus pathogenesis via investigation of honey bee virus host specificity and tissue tropism, and developing diagnoses and genetic analyses of viruses implicated in honey bee diseases. The research results from these efforts have been disseminated to state and federal regulators, stakeholders, and other researchers via presentations, diagnostic reports, and publications in trade and research journals.
A second focus was on the genome-wide gene expression in IAPV-challenged and uninfected bees using microarray analysis. Significant progress was made in the identification of host genes involved in specific immunity and pathways that can be exploited to develop RNAi-based strategies this coming year.