01188nas a2200217 4500008004100000022001400041245009500055210006900150260002900219300001400248490000700262520051900269653001600788653001200804653002300816653002300839653001900862653001700881100001700898856005500915 2008 eng d a1365-305900aThe biosecurity threat to the UK and global environment from international trade in plants0 abiosecurity threat to the UK and global environment from interna bBlackwell Publishing Ltd a792–8080 v573 aNative plant communities, woodlands and landscapes in the UK and across the world are suffering from pathogens introduced by human activities. Many of these pathogens arrive on or with living plants. The potential for damage in the future may be large, but current international regulations aimed at reducing the risks take insufficient account of scientific evidence and, in practice, are often highly inadequate. In this Letter I outline the problems and discuss some possible approaches to reducing the threats.10abiosecurity10aforests10ainvasive pathogens10anatural ecosystems10aPLANT diseases10aplant health1 aBrasier, C M uhttp://dx.doi.org/10.1111/j.1365-3059.2008.01886.x00323nas a2200097 4500008004100000245003900041210003900080300001200119100001500131856007900146 1924 eng d00aBud rot of coconut and other palms0 aBud rot of coconut and other palms a145-1471 aButler, EJ uhttps://forestphytophthoras.org/references/bud-rot-coconut-and-other-palms00524nas a2200109 4500008004100000245013600041210006900177300001200246490000700258100001400265856013500279 1883 eng d00aBeschadigung der Nadelhozsaatbeete durch Phytophthora omnivora (Fagi). (Damage in conifer seed beds by Phytophthora omnivora [Fagi]0 aBeschadigung der Nadelhozsaatbeete durch Phytophthora omnivora F a593-5960 v271 aHartig, R uhttps://forestphytophthoras.org/references/beschadigung-der-nadelhozsaatbeete-durch-phytophthora-omnivora-fagi-damage-conifer-seed02602nas a2200145 4500008004100000022001300041245011600054210006900170260001200239300001200251490000700263520209800270100001202368856007602380 2009 eng d a1437478100aBeech decline in Central Europe driven by the interaction between Phytophthora infections and climatic extremes0 aBeech decline in Central Europe driven by the interaction betwee c04/2009 a73 - 940 v393 a

During the past decade, and in particular after the wet year 2002 and the dry year 2003, an increasing number of trees and stands of European beech (Fagus sylvatica L.) in Bavaria were showing symptoms typical for Phytophthora diseases: increased transparency and crown dieback, small-sized and often yellowish foliage, root and collar rot and aerial bleeding cankers up to stem heights of >20 m. Between 2003 and 2007 134 mature beech stands on a broad range of geological substrates were surveyed, and collar rot and aerial bleeding cankers were found in 116 (86.6%) stands. In most stands the majority of beech trees were declining and scattered or clustered mortality occurred. Bark and soil samples were taken from 314 trees in 112 stands, and 11 Phytophthora species were recovered from 253 trees (80.6%) in 104 stands (92.9%). The most frequent species were P. citricola, P. cambivora and P. cactorum. Primary Phytophthora lesions were soon infected by a series of secondary bark pathogens, including Nectria coccinea, and wood decay fungi. In addition, infected trees were often attacked by several bark and wood boring insects leading to rapid mortality. Bark necroses were examined for their probable age in order to determine whether the onset of the current Phytophthora epidemic was correlated to rainfall rates recorded at 22 Bavarian forest ecosystem monitoring stations. A small-scale survey in nine Bavarian nurseries demonstrated regular infestations of all beech fields with the same range of Phytophthora species. The results indicate that (1) Phytophthora species are regularly associated with beech decline and may also be involved in the complex of ‘Beech Bark Disease’, (2) excessive rainfalls and droughts are triggering the disease, and (3) widespread Phytophthora infestations of nursery stock might endanger current and future silvicultural projects aiming on the replacement of non-natural conifer stands by beech dominated mixed stands.

1 aJung, T uhttp://onlinelibrary.wiley.com/doi/10.1111/efp.2009.39.issue-2/issuetoc02799nas a2200181 4500008004100000022001400041245011500055210006900170260002900239300001200268520220300280100001502483700001502498700001302513700001702526700001902543856005502562 2012 eng d a1439-032900aBehaviour and survival of Phytophthora cambivora inoculum in soil-like substrate under different water regimes0 aBehaviour and survival of Phytophthora cambivora inoculum in soi bBlackwell Publishing Ltd ano–no3 a

Phytophthora cambivora is a soil-borne pathogen responsible for root and collar rot of woody species including Castanea spp., on which it causes Ink disease. P. cambivora does not produce chlamydospores, and the prevalence of a single mating type in nature limits the production of oogonia and oospores. Thus, survival of P. cambivora, in the absence of suitable hosts, relies mainly on sporangia, zoospores and mycelium. However, inoculum survival in soils or substrates represents a major factor in disease epidemics and is probably dependant on environmental factors. The aim of this article was to study the behaviour of P. cambivora in a peat-based substrate (PbS) in the absence of a host, under controlled conditions, and by varying the substrate water regimes. Total inoculum in the substrate was quantified by qPCR, using customized rDNA primer sets, whilst zoospores were quantified after elution, and their vitality was determined by a specific staining procedure. Inoculum infectivity was assessed using chestnut root baits. Results indicated that during the initial 48 h after infestation (matric potential, pF 1.2; 70% water content), the inoculum level increased producing microsporangia and mycelium before decreasing, regardless of the water regime applied. The number of free zoospores increased over a period of (maximum) 7 days after substrate inoculation. Vitality of zoospores declined to 45% at day 18, with no statistical differences amongst water regime treatments. Both rDNA and zoospore number increased in flooded samples at day 23, illustrating the vitality of the inoculum. Inoculum was able to infect chestnut root baits up to 45 days at pF 1.2 and 3.5, before and after flooding, but at pF 6.3, only in the absence of flooding. Although based on experiments carried out in microcosms, these results highlight an unexpected resistance of P. cambivora zoospores to environmental constraints. Furthermore, the infectivity ability of the inoculum to survive in PbS over time even in the absence of the host adds relevance to the risk of movement of soil and substrates associated with plant trading worldwide.

1 aVannini, A1 aBreccia, M1 aBruni, N1 aTomassini, A1 aVettraino, A M uhttp://dx.doi.org/10.1111/j.1439-0329.2012.00768.x00535nas a2200145 4500008004100000022001400041245006400055210006000119260008700179300001200266490000700278100001300285700001400298856007700312 1987 eng d a0066-428600aThe biology of Phytophthora cinnamomi in Australian forests0 abiology of Phytophthora cinnamomi in Australian forests a{4139 EL CAMINO WAY, PO BOX 10139, PALO ALTO, CA 94303-0139}b{ANNUAL REVIEWS INC} a207-2290 v251 aWeste, G1 aMarks, CG uhttp://www.annualreviews.org/doi/abs/10.1146/annurev.py.25.090187.00123101781nas a2200157 4500008004100000022001400041245010300055210006900158260001600227300001600243490000700259520124500266100002401511700002301535856006501558 2015 eng d a0191-291700aBioassay Conditions for Infection of Pinus radiata Seedlings with Phytophthora pinifolia Zoospores0 aBioassay Conditions for Infection of Pinus radiata Seedlings wit cJan-09-2015 a1204 - 12090 v993 a

Phytophthora pinifolia is known to cause a devastating disease on Monterey pine in Chile. Although this pathogen is not yet present in the United States, there is reason for concern. The main source of Monterey pine genetic material is found in California and there is potential for other important tree species to be hosts. The study presented here was conducted to develop a method to produce zoospores and determine optimal conditions for infection to be used in future host range studies. Abundant zoospores were produced when agar plugs containing P. pinifolia mycelia were ground into suspension prior to transfer in a solution of carrot broth. These zoospores then were used to inoculate Monterey pine seedlings under various conditions. Infected plants displayed necrotic crowns and stems, often resulting in wilting of the seedling. Consistent infection occurred when seedlings were wounded by trimming needles prior to inoculation and exposure of inoculated seedlings to constant dew for 5 days. Dew chamber temperature (15, 20, or 25°C) did not affect the infection rate. Information obtained from this study will be useful in screening other hosts for susceptibility to P. pinifolia infection.

1 aWidmer, Timothy, L.1 aDodge, Stephen, C. uhttp://apsjournals.apsnet.org/doi/10.1094/PDIS-12-14-1306-RE00985nas a2200145 4500008004100000022001300041245008900054210006900143260001600212300000800228490000700236520052700243100002700770856004200797 1971 eng d a0031949X00aBlack-Butt Disease of Black Wattle Caused by Phytophthora nicotianae var. parasitica0 aBlackButt Disease of Black Wattle Caused by Phytophthora nicotia cJan-01-1971 a1440 v613 a

Inoculation experiments show that the black-butt disease of Black Wattle (Acacia mearnsii), cultivated for the high-quality tannins in its bark, appears to be caused by Phytophthora nicotianae var. parasitica. Two syndromes of the disease can be distinguished. The first takes the form of spreading mottled lesions, possibly related to infection by zoospores, and the second of tongues of diseased bark, originating from the penetration of mycelium.

1 aZeijlemaker, F., C. J. uhttps://doi.org/10.1094/phyto-61-144