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An indigenous betabaculovirus (PapyGV) of the Pandemis leafroller, Pandemis pyrusana (Kearfott), was studied in the laboratory and greenhouse to determine how the virus affected leafroller mortality and foliar damage. Probability of mortality increased with virus concentration as observed after 7 and 10 days of feeding on virus treated diet in neonates and second instar larvae. LC50 estimates for neonates at 7 and 10 days was 2743 and 389 occlusion bodies (OBs)/mm2. For second instars, LC50 was 139,487 and 813 OBs/mm2 at 7 and 10 days. There was no biologically significant mortality response to increasing virus concentrations by fourth instar larvae; however, when fourth instar larvae were infected with virus on diet and then fed apple leaves, the leaf area consumed declined up to 50% with higher virus concentrations. In a greenhouse study, neonate larvae that fed on seedlings treated with water showed >90% survival and 80% pupation rate of larvae after being transferred to diet. In contrast, larvae that fed on apple seedlings sprayed with 3×106 OBs/ml showed poor survival when transferred to diet after acquiring the virus and failed to reach the pupal stage. This virus shows promise for population regulation and can produce reduction in feeding damage. [ABSTRACT FROM AUTHOR]

The article reports on the evaluation of Tetramesa romana, Rhizaspidiotus and cryptonevra ssp. as the potential biological control agents in Austin, Texas. The research shows that adventive populations in Texas are identical but differ slightly from any of the populations collected in Europe. The research emphasizes that Tetramesa romana influence the formation of galls of Arundo donax L., since it oviposits into growing stems and lateral shoots.

The article reports that a hymenopteran parasitoid from silverleaf whitefly, also known as Bemisia tabaci, was submitted for identification on May 6, 2008 at the Systematic Entomology Laboratory in Texas. It states that the specimen has been identified by Gregory Evans as Encarsia sophia, which represents a new state record for the parasitoid/host association. It emphasizes that the silverleaf whitefly has been the target of a biological control program in the U.S. in the 1990s.

Culicoides biting midges (Diptera: Ceratopogonidae) are biological vectors of two important viruses impacting North American ruminants--bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV). These viruses have been identified for over 60 years in North America, but we still lack an adequate understanding of the basic biology and ecology of the confirmed vector, Culicoides sonorensis, and know even less about other putative Culicoides vector species. The major gaps in our knowledge of the biology of Culicoides midges are broad and include an understanding of the ecology of juveniles, the identity of potential alternate vector species, interactions of midges with both pathogens and vertebrates, and the effectiveness of potential control measures. Due to these broad and numerous fundamental knowledge gaps, vector biologists and livestock producers are left with few options to respond to or understand outbreaks of EHD or BT in North America, or respond to emerging or exotic Culicoides-transmitted pathogens. Here we outline current knowledge of vector ecology and control tactics for North American Culicoides species, and delineate research recommendations aimed to fill knowledge gaps.