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Phellinus noxius, the cause of brown root-rot disease, is an invasive fungal pathogen that causes a white rot among woody plants in Asia, Oceania, and Africa. Because the origin and diversity of this pathogen are unknown, it is difficult to predict its behavior and invasive capacity, especially under future climate-change scenarios. We characterized genetic relationships and ecological differences among P. noxius lineages across eastern Asia and Oceania to better understand evolutionary responses of the pathogen to environmental changes. Sequences of four loci (nuclear large subunit, internal transcribed spacers, partial RNA polymerase II, and partial translation elongation factor – 1 alpha) from 95 P. noxius isolates were used for genetic analyses. Our analyses revealed three genetically distinct lineages of P. noxius: 1) eastern Asia (Japan, Taiwan, Hong Kong, and Malaysia); 2) western Oceania/Japan/Taiwan (including Australia, Palau, Guam, Saipan, Yap, Pohnpei, and Kosrae) with some isolates from Japan and Taiwan; and 3) a distinct group from American Samoa. Population genetic analyses highlighted admixture and migration among the three lineages. Climate-based, species distribution models were used to predict ecological patterns of P. noxius for two genetic lineages: eastern Asia and western Oceania/Japan/Taiwan. Contemporary bioclimatic models depicted potential areas at high risk for P. noxius invasion, and predicted that suitable climate space (potential distribution) is lineage specific. Trade of important economic crops worldwide coupled with changing climates could exacerbate the spread of P. noxius into new geographic areas with suitable habitats for brown root-rot disease.

Some Amanita specimens collected from Malaysia are critically investigated by morphological examination and molecular analysis of two gene fragments, the nuc rDNA partial 28S (28S) gene and the internal transcriber spacer (ITS1-5.8S-ITS2 = ITS) regions. Six phylogenetic species of Amanita section Caesareae are recognized among the studied collections. One of them is described as new, A. malayensis. Four of the phylogenetic species correspond with existing morphology-based taxa: A. aporema, A. javanica, A. princeps, and A. similis. The remaining species is not described because of the paucity of material. Detailed descriptions and the distribution of these southeastern Asian species are provided, along with a key to the species of section Caesareae from Malaysia.

Hydnum is a fungal genus proposed by Linnaeus in the early time of modern taxonomy. It contains several ectomycorrhizal species which are commonly consumed worldwide. However, Hydnum is one of the most understudied fungal genera, especially from a molecular phylogenetic view. In this study, we extensively gathered specimens of Hydnum from Asia, Europe, America and Australasia, and analyzed them by using sequences of four gene fragments (ITS, nrLSU, tef1α and rpb1). Our phylogenetic analyses recognized at least 31 phylogenetic species within Hydnum, 15 of which were reported for the first time. Most Australasian species were recognized as strongly divergent old relics, but recent migration between Australasia and the Northern Hemisphere was also detected. Within the Northern Hemisphere, frequent historical biota exchanges between the Old World and the New World via both the North Atlantic Land Bridge and the Bering Land Bridge could be elucidated. Our study also revealed that most Hydnum species found in subalpine areas of the Hengduan Mountains in southwestern China occur in northeastern/northern China and Europe, indicating that the composition of the mycobiota in the Hengduan Mountains reigion is more complicated than what we have known before.

We present a taxonomic study of ‘group Favolus’ and related species in Polyporus. Phylogenetic analyses of nurLSU and ITS regions revealed that the infrageneric ‘group Favolus’ is divided into two main clades. Fungi within the group share laterally stipitate basidiocarps, with non-crustose stipe surfaces, and are distinguishable by the morphology of the pileus surface. One clade is characterized by species with hyaline to brown cutis, composed of hyaline to brown agglutinated generative hyphae. The other clade accommodates species with radially striate pileus, and lacks any distinct cutis of agglutinated hyphae. We propose Neofavolus gen. nov., typified by N. alveolaris, for the former clade, and revise the genus Favolus, typified by F. brasiliensis, for the latter clade. Neofavolus includes N. mikawai and N. cremeoalbidus sp. nov., known only from temperate eastern Asia, in addition to N. alveolaris. Favolus includes members of the Polyporus grammocephalus complex, the P. tenuiculus complex, and P. pseudobetulinus. We reveal that the polypore known as ‘P. grammocephalus’ in Asia includes F. acervatus and F. emerici (= P. grammocephalus), whereas ‘P. tenuiculus’ includes three distinct species; F. brasiliensis from tropical America, and F. spathulatus and F. roseus from tropical Asia. Detailed descriptions and illustrations are provided for the accepted species in Favolus and Neofavolus.

We reviewed the ecological characteristics of wood-inhabiting fungi in Malaysia in relation to the major threats to these fungi; we also examined the forest uses that would help to conserve them. Although wood-inhabiting fungi do not show high host specificity or preference in many tropical areas, several are specific to Dipterocarpaceae trees in Malaysia and some species may preferably inhabit other minor tree species. Tree size and decomposition stage are also important determinants of which fungi are present. Among the polypores described by E. J. H. Corner, 41 and 26 species have been recorded only from Malaysian lowland rainforest and montane forest, respectively. Evidence suggests that both of these forest types in Malaysia are home to unique fungal communities. More than 30 polypore species described by Corner are known only from their type localities. These species are likely rare and may be restricted to old-growth forests. Logging decreases species richness of wood-inhabiting fungi because the number of natural treefalls is decreased in logged forests, and the decline of old-growth forests is a major threat to conservation of Malaysian fungi. However, species richness of wood-inhabiting fungi is relatively high in old secondary forests and forests undergoing reduced-impact logging. The diversity of wood-inhabiting fungi is extremely low in oil palm plantations, whereas several species inhabit rubber-tree and acacia plantations. Preservation of old-growth forest is essential for conserving rare wood-inhabiting fungi in Malaysia, but old secondary forests, reduced-impact logged forests, and matured tree plantations may have some importance for the conservation of some species.

Batai (Falcataria moluccana) is a valuable tree species for forest plantations in Malaysia and Indonesia. Since 1993, a gall rust disease has caused severe damage to all growth stages, from seedlings in the nursery to mature trees in the field. To identify the fungus causing gall rust disease on F. moluccana in Malaysia and Indonesia, study of the mode of infection and changes in the anatomy of infected cells were carried out in the anatomy laboratory. The disease in Malaysia and Indonesia is caused by Uromycladium tepperianum. The fungus produces three longitudinally ridged teliospores on each head, with spores measuring 13–20 μm wide and 17–28 μm long. The fungus is microcyclic, completing its entire life cycle on F. moluccana. This study confirmed that the teliospores themselves cannot infect the host. Under favorable conditions, about 10 h after inoculation, teliospores germinate to produce basidiospores that form penetration pegs about 6 h later, and it is this peg which penetrates the host cells directly through the epidermis. Pycnia, recognized as small brown pustules, break through the epidermis about 7 days after inoculation.

The genus Amanita is well represented in tropical Africa, but most previous taxonomic studies were largely based only on morphology. In this study, we used both morphological and molecular data (nLSU sequences) to infer the phylogenetic relationships of ten species of Amanita sect. Vaginatae s.l. from tropical Africa. It was found that all five species with both an annulus and commonly present clamp connections in the basidioma were clustered in the sect. Caesareae. One species with neither an annulus nor clamp connections was placed in sect. Vaginatae s.s. The remaining four taxa with an annulus, but without clamp connections were interestingly also grouped into sect. Vaginatae s.s. with strong statistical support. Consequently, the section Vaginatae s.s. should be slightly modified to include tropical species with an annulus. As a new species, A. madagascariensis was described and illustrated. Amanita tanzanica was treated as a synonym of A. mafingensis.

Fungi play major roles in ecosystem processes, but the determinants of fungal diversity and biogeographic patterns remain poorly understood. Using DNA metabarcoding data from hundreds of globally distributed soil samples, we demonstrate that fungal richness is decoupled from plant diversity. The plant-to-fungus richness ratio declines exponentially toward the poles. Climatic factors, followed by edaphic and spatial variables, constitute the best predictors of fungal richness and community composition at the global scale. Fungi show similar latitudinal diversity gradients to other organisms, with several notable exceptions. These findings advance our understanding of global fungal diversity patterns and permit integration of fungi into a general macroecological framework.

A taxonomic study of poroid Asian species in the Auriculariales was conducted using phylogenetic and morphological methods. Phylogenetic analyses based on the LSU and ITS regions reveal that Elmerina was a polyphyletic genus. Moreover, E. hexagonoides collected from Malaysia and “E. hexagonoides” from Japan formed two distinct clades within a well-supported larger clade with Protomerulius caryae. These taxa comprise a different lineage from the type species of both Protomerulius and Protodaedalea, and we conclude that they are members of the genus Aporpium. The phylogenetic position of E. cladophora (type species of Elmerina) is still unclear, and we retain Aporpium and Protodaedalea as genera distinct from Elmerina. Aporpium strigosum sp. nov. is described to represent Japanese specimens misidentified as E. hexagonoides. Aporpium is characterized by resupinate to sessile basidiocarps, tough-fleshy to leathery context, poroid hymenophore, dimitic hyphal systems with unbranched skeletal hyphae, clavate to pyriform probasidia, and ellipsoid to cylindrical or allantoid basidiospores. Aporpium strigosum is similar to A. hexagonoides, but can be differentiated by the ochraceous to straw-colored basidiocarps, strigose pileus surface with long and stiff hairs, and the larger pores, basidia, and basidiospores.

Trunk rot poses a substantial threat to Sanbu-sugi, one of the most economically important cultivars of Japanese cedar (Cryptomeria japonica). The etiology of this disease, including its main agents, is incompletely known. This trunk rot was attributed to Fomitiporia (Phellinus) hartigii or F. (Phellinus) punctata. Here we phylogenetically analyzed DNA sequences of four markers from a set of strains isolated from trunk-rot symptoms and recovered a single, monophyletic clade, indicating that a single taxon is involved. This clade was identified as Fomitiporia torreyae, a species described from eastern China. This analysis also proved that trunk rot and/or dieback of other conifers and broadleaf trees, including Sawara cypress (Chamaecyparis pisifera), Japanese umbrella pine (Sciadopitys verticillata) and Japanese pear (Pyrus pyrifolia var. culta), were caused by the same species. The phylogenetic approach to Fomitiporia revealed that the F. torreyae clade was closely related to F. bannaensis but clearly distinct from F. punctata, which originally was thought to be the cause of trunk rot in Sanbu-sugi. Fomitiporia torreyae is redescribed on the basis of more than 40 specimens from multiple hosts from Japan and China. Fomitiporia juniperina comb. nov. is proposed.

We describe and illustrate two Strobilomyces species, S. seminudus and S. hongoi sp. nov. These two species have been confused and treated as a single species (i.e. S. seminudus). However recent studies based on population genetics have implied that they are reproductively isolated. In the present study we found that they are phylogenetically and morphologically distinct. The molecular phylogenetic trees inferred from the partial sequences of the largest subunit of RNA polymerase II (RPB1) and the second-largest subunit of RNA polymerase II (RPB2) support the differentiation of these two species as well as their differentiation from other related species. Strobilomyces seminudus is characterized by a stipe with an annular zone, becoming distinctly thickened near the apex and mottled with appressed-tomentose scales near the base. In contrast S. hongoi is characterized by a stipe with a remarkable reticulum at the upper and middle part and with minutely warty scales downward. Stipe characteristics also are useful for distinguishing these two species from other related species. In addition the incompletely reticulated basidiospores of these two species are also distinct from those of related species (i.e. S. foveatus).

One of the fundamental requirements for conducting research is access to and sharing of information. Traditionally, books and journals were the main sources of reference materials, but over the last decade, the Internet and other sources of electronic information have played an increasingly important role, e.g. the recent advent of APAFRI's E-loan and GFIS-ASIA. Electronic access varies tremendously within the ASEAN region. Researchers in Singapore, Malaysia, Brunei and Thailand have excellent to reasonably good access, but many in other ASEAN countries are not so fortunate. Many researchers may not even have access to a computer. However, even with good electronic access, the availability of appropriate information can vary. For example, university libraries in Malaysia with more generous budgets generally have much wider access than small research institutions, such as FRIM. Similarly, because of budget constraints and economies of scale, developing country research institutions find it difficult to subscribe to many international journals either in print or electronically. Close interaction and personal contact between researchers is one of the most important means of information access and exchange for researchers in developing countries. Senior researchers have the advantage over junior researchers who have yet to develop such extensive contacts. [ABSTRACT FROM AUTHOR]

The application of mycorrhizas in afforestation, reforestation and plantation establishment in Malaysia has largely remained in the experimental and trial stages. This has been due to a combination of factors, ranging from frequent changes in the choice of desired plantation tree species and the demand for fast-growing, short-rotation species, to the oversell of so-called “magic” solutions. There also has to be a significant increase in the number of mycorrhizal researchers to tackle the many aspects of mycorrhizal application so that some of the areas where data are lacking or insufficient may be overcome. It is clear that a considerable amount of fundamental as well as integrated-multidisciplinary research needs to be carried out before some of the already well-established biotechnological techniques, such as mycorrhizas, can be usefully applied to assist reforestation and plantation establishment in Malaysia.

Uninoculated dipterocarp seedlings raised in normal field soil in nurseries were always found to have mycorrhizas after a few months. This study set out to determine whether dipterocarp seedlings could continue to grow and develop in the absence of mycorrhizas and also to determine possible sources of mycorrhizal infection of dipterocarp seedlings raised under laboratory conditions using Shorea acuminata as a typical example. Seedlings were planted in capped or uncapped perspex boxes containing sterile or non-sterile field soil and watered daily with sterile water or tap water. Seedling growth and development of mycorrhizas were monitored at monthly intervals for up to seven months. Seedlings grown in sterile soil remained uninfected after seven months while infection was found in some of the seedlings grown in normal soil regardless of whether they had been watered with tap water or sterile water. This showed that field soil (i.e. under grass) far from the forest contained suitable inoculum for forest tree seedlings. Tap water and the air were not important sources of infection. However, mycorrhizal infection was very uneven indicating that the inoculum was probably very unevenly distributed in the soil or that the inoculum density was rather low. Seedlings grown in sterile soil showed better growth than those grown in normal soil and infection of roots by parasitic fungi in the latter was also observed. Key words: Mycorrhizas/Plant pathology/lnfections/Shorea acuminata/Seedlings.

Fungal sporocarps and cultures associated with signs and symptoms of root-rot disease were collected from Acacia mangium and other tropical hardwood species. The collections were identified by either morphological characters and/or by phylogenetic analysis based on DNA sequences as Ganoderma philippii, G. mastoporum, G. aff. steyaertanum, G. australe and Amauroderma rugosum. Phylogenetic analysis unequivocally placed in the G. philippii clade four sequences amplified from A. mangium root and butt tissue showing clear signs of red root-rot disease (roots are covered by a red rhizomorphic skin). Whereas G. philippii was the most frequently encountered fungal species in A. mangium with red root-rot disease, this study indicates that other fungal species related to G. mastoporum may cause root-rot disease with very similar symptoms. An isolate (FRIM 138) that had caused red root-rot disease in artificial inoculations carried out before this study and was presumed to be G. philippii, is here determined to be closely related to G. mastoporum, G. cupreum and G. sinense. A Ganoderma species associated with a yellow-brown root-rot disease killing trees in an A. mangium plantation in Central Java, previously identified as G. lucidum, is shown by phylogenetic analysis to be closely related to G. steyaertanum, though some morphological characters vary from the original description of that species.

Wood decay associated with wounding in 40 trees of Parashorea malaanonan growing in Ulu Segama Forest Reserve, Sabah, Malaysia, was estimated 7 years after logging in compartments where reduced-impact (RIL) or conventional (CL) logging methods were used. Trees of ≥30 cm diameter were felled and dissected to determine the volume of log occupied by decay. Scrapes were the most common types of wounds sampled, followed by basal wounds, broken tops or branches and butt log wounds. All wounded trees examined had decay, whereas only 25% of trees ×30 cm diameter at breast height of this species in the reserve typically had stem decay. Median defect to gross volume of tree was ∼5%, and was similar for trees in RIL and CL areas. However, defect volume per wound was greater in trees from CL areas relative to RIL areas, in particular, mid-bole wounds had greater defect volume in trees in CL areas as opposed to trees in RIL areas. The mean rate of decay was estimated at 68 cm3 of timber per year for each cm2 of wound area. Defect volume was positively correlated with wound size but was unrelated to tree size. P. malaanonan is vulnerable to wood decay following wounding; therefore, in eastern Sabah forests, where this species comprises a large proportion of the commercial volume, efforts to reduce incidental damage to residual stems during harvesting operations are an important component in protecting the growing stock.

This is the first report of basal root rot of teak, caused by Phellinus noxius, in Peninsular Malaysia. The disease aggressively killed its host irrespective of health status. Bark depression at the root collar was a very characteristic symptom of this disease on teak and was visible from a distance. Below ground, infected trees had rotted root systems, mainly at the collar region, brown discoloured wood and irregular golden-brown honeycomb-like pockets of fungal hyphae in the roots. Pathogenicity tests showed that the fungus killed 2-year-old teak saplings gradually, producing below- and above ground-symptoms similar to those in the plantation. The disease killed all the infected hosts within 3 months, irrespective of wounded or unwounded treatments. Additional keywords: forest plantation, root disease, teak, Tectona grandis.