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The fungus Phellinus noxius has a broad host range and causes brown root rot in a variety of tree species of various ages, irrespective of their original health. The fungus is widely distributed in tropical countries of Southeast Asia, the Pacific Islands and Australia, Central America and Caribbean, and Africa. Since 1988, when brown root rot was first found on Ishigaki Island, Okinawa Prefecture, the disease has been reported on several islands in Okinawa and Kagoshima Prefectures, and it has been causing serious problems to shade, windbreak, ornamental and landscape trees in the Ryukyu Islands, located in the subtropical region of southern Japan. Here, we report on the current status of P. noxius-caused brown root rot in the Ryukyu Islands, Japan, including symptoms, occurrence, dispersal, distribution and host tree species of the disease, pathogenicity and/or virulence of the pathogen, and disease management based on our surveys and previously published reports from Japan. Brown root rot has been confirmed in 53 tree species from 32 plant families at different sites on 10 of the 12 islands surveyed. Among the 53 tree species, 34 were first recorded in Japan as host plants of P. noxius. The disease occurs mainly in shade, ornamental and windbreak trees at sightseeing places, parks, roadsides, agricultural land such as sugar cane fields, and around residences or other places associated with human activities. [ABSTRACT FROM AUTHOR]

Summary Distribution, host preference and pathogenicity of Japanese Armillaria species on conifers were investigated on the basis of field collections of 65 isolates. We identified seven Armillaria species from 19 conifer species including six major Japanese plantation conifers using mating tests and sequences of the translation elongation-1 α gene. Armillaria mellea, Armillaria ostoyae, Armillaria cepistipes and Armillaria sinapina were frequently collected, whereas Armillaria nabsnona, Armillaria tabescens and a biological species Nagasawa's E were rare. On the basis of host condition when the isolates were collected, A. mellea, A. ostoyae, A. cepistipes and A. tabescens are considered as moderate to aggressive pathogens of conifers in Japan. [ABSTRACT FROM AUTHOR]

The article examines pathogenicity of colletotrichum dematium (C. dematium) isolated from current-year beech seedlings exhibiting damping-off. The pathogenicity of C. dematium was evaluated as the agent causing post-emergence damping-off of current-year beech seedlings. Current-year beech seedlings inoculated with C. dematium died within 20 days after both wound and non-wound inoculation, indicating that the fungus is pathogenic to current-year seedlings. The incidence of isolation was high and little variation occurred between sites and years. C. dematium was also detected in all litter samples examined although the incidence of detection differed depending on sites and detection methods.

Brown root rot disease (BRRD) is a highly destructive tree disease. Early diagnosis of BRRD has been challenging because the first symptoms and signs are often observed after extensive tissue colonization. Existing molecular detection methods, all based on the internal transcribed spacer (ITS) region, were developed without testing against global Phellinus noxius isolates, other wood-decay fungi, or host plant tissues. This study aimed to develop SYBR Green real-time quantitative PCR (qPCR) assays for P. noxius . The primer pair Pn_ITS_F/Pn_ITS_R targets the ITS, and the primer pair Pn_NLR_F/Pn_NLR_R targets a P. noxius -unique group of homologous genes identified through a comparative genomics analysis. The homologous genes belong to the nucleotide-binding-oligomerization-domain-like receptor (NLR) superfamily. The new primer pairs and a previous primer pair G1F/G1R were optimized for qPCR conditions and tested for specificity using 61 global P. noxius isolates, 5 other Phellinus species, and 22 non- Phellinus wood-decay fungal species. Although all three primer pairs could detect as little as 100 fg (approximately 2.99 copies) of P. noxius genomic DNA, G1F/G1R had the highest specificity and Pn_NLR_F/Pn_NLR_R had the highest efficiency. To avoid false positives, the cutoff quantification cycle values were determined as 34 for G1F/G1R, 29 for Pn_ITS_F/Pn_ITS_R, and 32 for Pn_NLR_F/Pn_NLR_R. We further validated these qPCR assays using Ficus benjamina seedlings artificially inoculated with P. noxius , six tree species naturally infected by P. noxius , rhizosphere soil, and bulk soil. The newly developed qPCR assays provide sensitive detection and quantification of P. noxius , which is useful for long-term monitoring of BRRD status., Competing Interests: The author(s) declare no conflict of interest.

Brown root rot disease (BRRD), caused by Phellinus noxius , is an important tree disease in tropical and subtropical areas. To improve chemical control of BRRD and deter emergence of fungicide resistance in P . noxius , this study investigated control efficacies and systemic activities of fungicides with different modes of action. Fourteen fungicides with 11 different modes of action were tested for inhibitory effects in vitro on 39 P. noxius isolates from Taiwan, Hong Kong, Malaysia, Australia, and Pacific Islands. Cyproconazole, epoxiconazole, and tebuconazole (Fungicide Resistance Action Committee [FRAC] 3, target-site G1) inhibited colony growth of P. noxius by 99.9 to 100% at 10 ppm and 97.7 to 99.8% at 1 ppm. The other effective fungicide was cyprodinil + fludioxonil (FRAC 9 + 12, target-site D1 + E2), which showed growth inhibition of 96.9% at 10 ppm and 88.6% at 1 ppm. Acropetal translocation of six selected fungicides was evaluated in bishop wood ( Bischofia javanica ) seedlings by immersion of the root tips in each fungicide at 100 ppm, followed by liquid or gas chromatography tandem mass spectrometry analyses of consecutive segments of root, stem, and leaf tissues at 7 and 21 days posttreatment. Bidirectional translocation of the fungicides was also evaluated by stem injection of fungicide stock solutions. Cyproconazole and tebuconazole were the most readily absorbed by roots and efficiently transported acropetally. Greenhouse experiments suggested that cyproconazole, tebuconazole, and epoxiconazole have a slightly higher potential for controlling BRRD than mepronil, prochloraz, and cyprodinil + fludioxonil. Because all tested fungicides lacked basipetal translocation, soil drenching should be considered instead of trunk injection for their use in BRRD control., Competing Interests: The author(s) declare no conflict of interest.

Although automated pollen monitoring networks using laser optics are well-established in Japan, it is thought that these methods cannot distinguish between pollen counts when evaluating various pollen taxa. However, a method for distinguishing the pollen counts of two pollen taxa was recently developed. In this study, we applied such a method to field evaluate the data of the two main allergens in Japan, Chamaecyparis obtusa and Cryptomeria japonica. We showed that the method can distinguish between the pollen counts of these two species even when they are simultaneously present in the atmosphere. This result indicates that a method for automated and simple two pollen taxa monitoring with high spatial density can be developed using the existing pollen network., (© 2021. The Author(s).)

Background: In 1986, the Ministry of Health and Welfare started an airborne pollen survey as part of measures against JC pollinosis. We reported the important tree pollen antigens in 2016. We have now estimated the longitudinal investigated results for successful prevention and treatment for allergic symptoms related to grass and weed pollen in Japan., Method: Since July 1986 we have monitored airborne pollen, year- round, using a gravitational pollen sampler (Durham's sampler), at more than 20 locations across Japan. Specimens were mailed to our facility, where they were stained with Calberla solution, counted under an optical microscope, and converted to the number of pollen per square centimeter. For convenience the number of collected pollen were compiled every six months, with the January to June samples classified as spring pollen and the July to December as autumn pollen even same family., Result: Total pollen counts at each location were extremely small compared to tree-pollen, averaging 73~650 pollen grains per year. The Sagamihara location had the greatest count. Unlike cedar and cypress there were no significant annual fluctuations, but grass and Ambrosia pollen counts are increasing in some regions. Spring grass pollen gave the largest count, at 30% of the total collected., Conclusion: This indicated we need to examine the rinoconjuctivitis and oral allergy syndrome related to herbaceous pollen carefully.The importance of airborne pollen surveys for the treatment of the patients with pollen allergies was suggested.

The order Hymenochaetales of white rot fungi contain some of the most aggressive wood decayers causing tree deaths around the world. Despite their ecological importance and the impact of diseases they cause, little is known about the evolution and transmission patterns of these pathogens. Here, we sequenced and undertook comparative genomic analyses of Hymenochaetales genomes using brown root rot fungus Phellinus noxius, wood-decomposing fungus Phellinus lamaensis, laminated root rot fungus Phellinus sulphurascens and trunk pathogen Porodaedalea pini. Many gene families of lignin-degrading enzymes were identified from these fungi, reflecting their ability as white rot fungi. Comparing against distant fungi highlighted the expansion of 1,3-beta-glucan synthases in P. noxius, which may account for its fast-growing attribute. We identified 13 linkage groups conserved within Agaricomycetes, suggesting the evolution of stable karyotypes. We determined that P. noxius has a bipolar heterothallic mating system, with unusual highly expanded ~60 kb A locus as a result of accumulating gene transposition. We investigated the population genomics of 60 P. noxius isolates across multiple islands of the Asia Pacific region. Whole-genome sequencing showed this multinucleate species contains abundant poly-allelic single nucleotide polymorphisms with atypical allele frequencies. Different patterns of intra-isolate polymorphism reflect mono-/heterokaryotic states which are both prevalent in nature. We have shown two genetically separated lineages with one spanning across many islands despite the geographical barriers. Both populations possess extraordinary genetic diversity and show contrasting evolutionary scenarios. These results provide a framework to further investigate the genetic basis underlying the fitness and virulence of white rot fungi., (© 2017 John Wiley & Sons Ltd.)

Rational: In Japan patients with Japanese Cedar (JC) pollinosis have increased nation widely since the latter of 1970's. The Ministry of Health and Welfare of Japanese Governments has begun to take preventive measures against JC pollinosis and airborne pollen monitoring has begun to investigate as a causative agent since 1986. We have estimated the longitudinal investigation result for successful prevention and treatment against pollinosis in Japan., Method: We have monitored airborne pollen all year around since July 1986 by gravitational pollen sampler, Durham's sampler, at more than 20 locations in the Japanese Islands. Pollen samples were sent to our hospital and counted pollen number per cm 2 after stained by Calberla solution and then classified main pollen grains as a causative agent of pollinosis., Result and Discussion: JC pollen number was the most of all, more than 40%, next cypress family, about 20%. They were occupied of more than 60% of all and they increased with the remarkable annual fluctuation as the allergen of JC pollinosis. Beech family pollen counting were also increasing and occupied about 10% of all pollen counts. In Hokkaido the prevalence of birch family pollen count was larger than that in other districts. There is cross-reactivity between beech and birch family which related with oral allergic syndrome.Perspective and Conclusion: In future new occurrences of oral allergy syndrome due to increasing allergic tree pollen grains would be appeared. The contentious pollen research should be important for patients with pollinosis in Japan.

Phellinus noxius is a pathogenic fungus that causes brown root rot disease in a variety of tree species. This fungus is distributed in tropical and sub-tropical regions of Southeast and East Asia, Oceania, Australia, Central America and Africa. In Japan, it was first discovered on Ishigaki Island in Okinawa Prefecture in 1988; since then, it has been found on several of the Ryukyu Islands. Recently, this fungus was identified from the Ogasawara (Bonin) Islands, where it has killed trees, including rare endemic tree species. For effective control or quarantine methods, it is important to clarify whether the Japanese populations of P. noxius are indigenous to the area or if they have been introduced from other areas. We developed 20 microsatellite markers from genome assembly of P. noxius and genotyped 128 isolates from 12 of the Ryukyu Islands and 3 of the Ogasawara Islands. All isolates had unique genotypes, indicating that basidiospore infection is a primary dissemination method for the formation of new disease foci. Genetic structure analyses strongly supported genetic differentiation between the Ryukyu populations and the Ogasawara populations of P. noxius. High polymorphism of microsatellite loci suggests that Japanese populations are indigenous or were introduced a very long time ago. We discuss differences in invasion patterns between the Ryukyu Islands and the Ogasawara Islands.

Taphrina fungi are biotrophic plant pathogens that cause plant deformity diseases. We sequenced the genomes of four Taphrina species-Taphrina wiesneri, T. deformans, T. flavorubra, and T. populina-which parasitize Prunus, Cerasus, and Populus hosts with varying severity of disease symptoms. High levels of gene synteny within Taphrina species were observed, and our comparative analysis further revealed that these fungi may utilize multiple strategies in coping with the host environment that are also found in some specialized dimorphic species. These include species-specific aneuploidy and clusters of highly diverged secreted proteins located at subtelomeres. We also identified species differences in plant hormone biosynthesis pathways, which may contribute to varying degree of disease symptoms. The genomes provide a rich resource for investigation into Taphrina biology and evolutionary studies across the basal ascomycetes clade.

Pine wilt disease is one of the most serious epidemic tree diseases in Japan, and resistant pine trees have been developed through a breeding program. To evaluate resistance of resistant families of Japanese black pine, Pinus thunbergii, to the pinewood nematode, Bursaphelenchus xylophilus, isolated from the field, and to determine whether differentiation of pathogenicity to resistant pine families appears in the nematode isolates, seedlings of five resistant pine families were inoculated with 25 nematode isolates. Disease incidence 18 weeks after inoculation was significantly different among nematode isolates and among pine families but there was no interaction effect between nematode isolate and pine family. This indicates that nematode isolates did not have differential host specificity to resistant families of P. thunbergii. Isolate Shimabara, a test isolate of the breeding program, showed the same degree of virulence as the highly virulent isolates frequently used in experiments. However, more virulent isolates than Shimabara were found among the isolates collected from natural pine forest. This indicated that B. xylophilus populations with higher virulence than Shimabara exist in the natural population. These findings are important in development of more efficient breeding procedures for resistant pine trees.

Bursaphelenchus xylophilus is the nematode responsible for a devastating epidemic of pine wilt disease in Asia and Europe, and represents a recent, independent origin of plant parasitism in nematodes, ecologically and taxonomically distinct from other nematodes for which genomic data is available. As well as being an important pathogen, the B. xylophilus genome thus provides a unique opportunity to study the evolution and mechanism of plant parasitism. Here, we present a high-quality draft genome sequence from an inbred line of B. xylophilus, and use this to investigate the biological basis of its complex ecology which combines fungal feeding, plant parasitic and insect-associated stages. We focus particularly on putative parasitism genes as well as those linked to other key biological processes and demonstrate that B. xylophilus is well endowed with RNA interference effectors, peptidergic neurotransmitters (including the first description of ins genes in a parasite) stress response and developmental genes and has a contracted set of chemosensory receptors. B. xylophilus has the largest number of digestive proteases known for any nematode and displays expanded families of lysosome pathway genes, ABC transporters and cytochrome P450 pathway genes. This expansion in digestive and detoxification proteins may reflect the unusual diversity in foods it exploits and environments it encounters during its life cycle. In addition, B. xylophilus possesses a unique complement of plant cell wall modifying proteins acquired by horizontal gene transfer, underscoring the impact of this process on the evolution of plant parasitism by nematodes. Together with the lack of proteins homologous to effectors from other plant parasitic nematodes, this confirms the distinctive molecular basis of plant parasitism in the Bursaphelenchus lineage. The genome sequence of B. xylophilus adds to the diversity of genomic data for nematodes, and will be an important resource in understanding the biology of this unusual parasite.

Brown root rot, caused by Phellinus noxius, leads to problems in management of shade, ornamental, and windbreak trees in subtropical regions of the world, and it has been causing serious problems in Japan since 1988. To identify the pathogenicity, host specialization, and virulence of the pathogen, cross inoculation tests were carried out using isolates of the fungus obtained from nine different tree species. P. noxius was pathogenic to all of the nine tree species tested, and it killed inoculated seedlings. Among the 810 trees inoculated with the fungus, a total of 141 trees (17.4%), including all nine species, were dead within 110 days after inoculation. The first symptom of infection was rapid wilt with discoloration of leaves 20 to 30 days after inoculation, and then the plants quickly declined. Only one isolate of P. noxius that was tested caused significantly higher mortality in its original host than in other species, suggesting that the pathogen has little to no host specificity. However, the fungus did show variation in virulence, with the isolates originating in Bischofia javanica and Casuarina equisetifolia causing significantly higher mortality than those collected from other host species. More isolates of P. noxius from the same host species and/or from various countries should be studied to understand host specialization and virulence of the pathogen.

We determined pollen specific IgE in tears and compared these results to the concentration of specific IgE in serum samples. We obtained tears (using Schirmer strips) and serum samples from subjects with Japanese cedar (Cryptomeria japonica) pollinosis, and tested for C. japonica pollen specific IgE using a quantitative ELISA. Time kinetic analyses through the pollen season showed that specific IgE levels in tears were found to increase earlier than those in sera and reached their maximum at the end of or after the pollen season, from March to early June. In the C. japonica pollen free season, July to December, the specific IgE levels in tears decreased, although the serum levels remained relatively high. These results indicate that the quantitative assay for specific IgE in tears might be useful to identify specific eye allergens.

Glucagon, a key regulatory element of glycogen metabolism, is known to be effective in the clinical treatment of hypoglycemia and the maintenance of normal circulating glucose levels in patients with total pancreatectomy, however the clinical use of this gut hormone has been restricted to parenteral administration. In this investigation, we prepared dry powder dosage forms of glucagon, which were formulated by mixing micronized glucagon particles and excipients with larger carrier particles. To achieve alveolar deposition for subsequent systemic absorption, a dry powder inhalant (DPI) of glucagon was size-reduced to a mass median diameter between 1 and 6 microm, as measured by laser diffraction analysis. The use of erythritol as both excipient and carrier in DPI of glucagon resulted in high and reproducible flowability and dispersibility of the powder mixtures, and therefore it provided a low dosing of the active substances. Distinct transpulmonary absorption of glucagon was confirmed after intratracheal administration of the glucagon dry powder to anesthetized rats, as evidenced by the increase in the blood glucagon and blood sugar levels. These results suggested the usefulness of an erythritol-based powder form of glucagon for systemic administration.

It is very important to predict and disseminate information about the total pollen counts of both Cryptomeria japonica and Cupressaceae for patients with pollinosis. In Okayama Prefecture, we have reported that the pollen counts of both Cryptomeria japonica and Cupressaceae are influenced by the meteorological conditions in the previous July. We predicted the area supplying Okayama Prefecture with Cryptomeria japonica and Cupressaceae pollen, and also the route of airborne pollen from the meteorological conditions and a topographical map of Okayama and four neighboring prefectures. It was found that Cryptomeria japonica and Cupressaceae pollen counts at the four observation sites correlated very well with the meteorological conditions at Tsuyama weather station in Okayama prefecture. Therefore, we considered that the areas supplying Okayama prefecture with Cryptomeria japonica and Cupressaceae pollen were the central northern areas including Tsuyama, 85.7% of whose plantation areas contained Cryptomeria japonica and Chamaecyparis obtusa, and that their pollen was carried along the routes of three major rivers, R. Takahashi, R. Asahi and R. Yoshii.

Objective: To investigate the prevalence of Orchard Pollinosis in China., Method: From 1995 to 1998, an epidemiological survey on orchard pollinosis was carried on among 1,660 primary and middle school students and 2,167 university students, including questionnaire investigation, nasal inspection and scratch test. From April to June of 1998, a clinical investigation of orchard pollinosis was adopted among 30 patients of allergic rhinitis including scratch test and nasal mucosa test., Result: 1. The total positive rate of orchard pollen scratch test was 6.7%, and the prevalence of orchard pollinosis was 0.37%. 2. 5 cases (16.7%) were hypersensitive to orchard pollen clinically in allergen test., Conclusion: Orchard pollinosis is one kind of important pollinosis and should be paid high attention to.

Prevalence rate of allergy to Japanese cedar pollen was investigated by means of questionnaires and immunological examinations in residents of 3 regions in Tokyo (Akiruno city, Chofu city, and Ota ward). The results were as follows: 1) the prevalence rate of allergy to Japanese cedar pollen in Tokyo was 25.7% in Akiruno city, 21.1% in Chofu city, and 17.7% in Ota ward in 1996; 2) stratification by the age reveal that the prevalence rate was the highest in the age group of 30 to 44, and the group showed prevalence rate of above 40% in Akiruno city; 3) overall prevalence rate of Tokyo was 19.4% in 1996, which was approximately twice as much as that in 1985; 4) increase in prevalence rate in the recent decade was most significant in Akiruno city where the largest number of Japanese cedar pollen was detected in the air, and prevalence rate tended to rise in the young group of 14 or less.

It is important to forecast the beginning day of Japanese cedar pollen release for taking the preventive medical measure. We analyzed the relation between the beginning day of pollen release and the changing pattern of daily air temperature. A simple and practical method for forecasting the beginning day of pollen release is suggested. Polynomial of degree three was applied to represent the general variation pattern of air temperature. Multiple correlation coefficients between parameters of the polynomial and the beginning days of pollen release were 0.88 for the difference by year, and 0.81 for the difference by place. It was shown that the minimum value and the date of the fitted polynomial curve were related closely to the difference in the beginning day of pollen release by year. The minimum value and the date of the original series of air temperature showed high correlation with the difference in the beginning day of pollen release by place. We propose to use the minimum value and the date of original series and fitted curve of air temperature for forecasting the beginning day of cedar pollen release.

Background: There have been no detailed long-term observations of the relationship between specific IgE production and stimulation by various naturally occurring allergens., Objective: This study was conducted to elucidate the yearly and seasonal changes of specific IgE antibody production to Japanese cedar pollen, an allergen of Japanese cedar pollinosis, in young adults., Methods: The number of Japanese cedar pollen were counted over a period of 9 years. Changes in the percentages of antibody carriers to Japanese cedar pollen and mite were examined during these years. Changes in Japanese cedar pollen-specific IgE levels between a low exposure year and a high exposure year in individual subjects were also investigated., Results: From 1987 to 1995, the percentages of Japanese cedar pollen-IgE carriers varied from about 30% to 50% with the intensity of pollen stimulation, and carriers tended to increase yearly. The rates of anti-mite IgE carriers changed little. In the spring which is the pollen season, Japanese cedar pollen-IgE levels in low exposure years were weaker than those in high exposure years in individual subjects. Levels in autumn, which is not the pollen season, showed equivalent levels in both high and low exposure years. Anti-mite IgE levels in individual subjects varied little during these years., Conclusions: A long-term follow-up study supported that Japanese cedar pollen-IgE production is mainly associated with the degree of allergen exposure.

Allergic conjunctivitis caused by sugi pollen is considered to be strictly a "spring disease". However, a recent report indicated that sugi pollen is scattered not only in spring but in all seasons, especially in the autumn. We retrospectively determined the number of patients with allergic conjunctivitis caused by sugi pollen during each month for 3 consecutive years, and also investigated the growth of sugi male cones in November for four years. Diagnosis of allergic conjunctivitis was based on symptomatic complaints, clinical findings, and serum sugi pollen specific IgE measured by the Multiple Antigen Simultaneous Test 16. The annual incidence of allergic conjunctivitis peaked twice, once in spring and again in autumn. Scattering of sugi pollen occurred mostly in March and October, whilst the growth of sugi male cones was highest in November. Thus, allergy to sugi pollen can cause allergic conjunctivitis both in the spring and late autumn.

A map of pollen fronts of Cryptomeria japonica was compiled from pollen counts taken at 28 airborne sampling sites in Japan in 1986. Thereafter, the number of sites was increased, reaching 80 in 1991. In this way an accurate and complete map of the C. japonica pollen fronts was compiled annually. We used the results obtained from mapping the pollen fronts to draw up a map of the average locations of the front, from which the beginning of the pollen season can be predicted. A close correlation was found between the latitude of the airborne sampling sites and the mean interval between January 1 and the day pollen release began during these 6 years.