Incidence of Phytophthora infestans (Mont.) de Bary on potato and tomato in Maine, 2006–2010

Late blight, caused by Phytophthora infestans (Mont.) de Bary, is a devastating disease which is found worldwide. In Maine, United States (US), we recorded late blight on potato and tomato during the 2006-2009 cropping seasons. From 2006 to 2008, over 90% of the diseased samples were collected in potato fields from northern and central Aroostook County in Northern Maine, US. Then, in 2009, an unprecedented influx of inoculum on infected tomato transplants shipped to retail garden centers throughout the Northeast US significantly changed the late blight infection patterns. In 2009, 43% of diseased samples obtained were from tomato, and 57% from potato, and disease was found to occur all over the state. Moran’s index and spatial autocorrelation analysis of disease occurrence, geographical locations, host factors, and infection levels from previous years, were not statistically significant (p > 0.05). Therefore, random distributions of late blight incidences were recorded across locations and years. Nearest neighbor analysis revealed that mean spatial distances for late blight occurrence ranged from 1.51 to 71.4 km from 2006 to 2008, and 7.4 to 126.5 km in 2009. The frequency and locations of late blight outbreaks in 2009 were substantially greater than in 2006, 2007, and 2008, as affected by the influx of inoculum and movement of infected tomato seedlings as well as conducive environmental conditions. All were contributing factors for late blight occurrence in Maine. In 2010, few disease samples were collected, indicating that the influx of inoculum in 2009 did not persist to cause widespread disease in 2010. The reduction of inocula sources, fungicide protection of susceptible hosts, and the removal and destruction of infected tomato seedlings and potato cull piles or volunteer plants, can greatly reduce late blight occurrences and improve potato production. These actions should be considered as an integral part of late blight management programmes in regions where late blight commonly occurs

Late Ordovician (Ashgill) Foliomena fauna brachiopods from northeastern Maine

Foliomena folium (Barrande) and other very small, thin-shelled brachiopods from the Pyle Mountain Argillite in Aroostook County, Maine, provide the only record of the presence of the Foliomena fauna in North America. Associated fossils include numerous small trilobites and a few specimens of other groups. An Ashgill age is established by the presence of graptolites of the Climacograptus spiniferous Zone in the underlying Winterville Formation.Most of the 190 specimens are small strophomenaceans and plectambonitaceans. One of the most numerous is the christianiid Nubialba forbesi n. gen. and sp. that has ribs and elaborately developed internal features. In the absence of evidence to contradict previous interpretations that the Foliomena fauna records cold-water environments, the presence of one or more deep basins along the southeastern margin of the trans-equatorial North American paleoplate occupied by cool peri-Gondwanan waters during a short segment of Ashgill time is implied.