Species Diversity With Comprehensive Annotations of Wood-Inhabiting Poroid and Corticioid Fungi in Uzbekistan

Uzbekistan, located in Central Asia, harbors high diversity of woody plants. Diversity of wood-inhabiting fungi in the country, however, remained poorly known. This study summarizes the wood-inhabiting basidiomycte fungi (poroid and corticoid fungi plus similar taxa such as Merismodes, Phellodon, and Sarcodon) (Agaricomycetes, Basidiomycota) that have been found in Uzbekistan from 1950 to 2020. This work is based on 790 fungal occurrence records: 185 from recently collected specimens, 101 from herbarium specimens made by earlier collectors, and 504 from literature-based records. All data were deposited as a species occurrence record dataset in the Global Biodiversity Information Facility and also summarized in the form of an annotated checklist in this paper. All 286 available specimens were morphologically examined. For 138 specimens, the 114 ITS and 85 LSU nrDNA sequences were newly sequenced and used for phylogenetic analysis. In total, we confirm the presence of 153 species of wood-inhabiting poroid and corticioid fungi in Uzbekistan, of which 31 species are reported for the first time in Uzbekistan, including 19 that are also new to Central Asia. These 153 fungal species inhabit 100 host species from 42 genera of 23 families. Polyporales and Hymenochaetales are the most recorded fungal orders and are most widely distributed around the study area. This study provides the first comprehensively updated and annotated the checklist of wood-inhabiting poroid and corticioid fungi in Uzbekistan. Such study should be expanded to other countries to further clarify species diversity of wood-inhabiting fungi around Central Asia.


INTRODUCTION
Central Asia is a biological crossroads at the most westerly part of the Himalayan range and supports both Palearctic species and others representative of more southerly subtropical latitudes. The peculiarity of fauna and flora is due to its mixed characters: Indo-Himalayan, Mongolian, Eurasian, and Mediterranean species are present (Anonymous, 2001). Uzbekistan in the heart of Central Asia has a diversity of habitats that are globally and regionally important in ecological functions. The varying landscapes of high mountain ranges, wide steppes, deserts, and riparian wetlands in Uzbekistan result in a high diversity of habitats. The mountain areas occupy 15% of the territory of Uzbekistan. Biodiversity of Uzbekistan includes more than 27,000 species, including over 15,000 animal species; plants, algae, and fungi total about 11,000 species (Anonymous, 1998). The flora of Uzbekistan includes 4500 species of vascular plants, of which about 400 species are endemic, rare, and relict. Many of the animals and higher plants are included in the Red List of the International Union for Conservation of Nature (IUCN) and the Red Book of the Republic of Uzbekistan.
In contrast to the great number of publications dealing with the flora, limited studies document the fungi in Uzbekistan and Central Asia in general . Current surveys in areas of high plant endemism, such as tropical and subtropical regions, are actually showing an even higher ratio of fungal to plant diversity and uncovering an extraordinary number of endemic fungi (e.g., Crous et al., 2006;Mueller and Schmit, 2007;Schmit and Mueller, 2007;Aime and Brearley, 2012;Hawksworth, 2012). Mountains of the Central Asia Biodiversity Hotspot consist of two major mountain systems, the Pamir and the Tien Shan. Both belong to the most diverse regions in the world with respect to fauna and flora and are regarded as areas of occurrence of many endemic, relict, and endangered species. Therefore, diverse and regionally limited fungi are expected to exist in the region. However, while knowledge of fungal diversity is developing rapidly in some areas of the world, data on the fungi in Central Asia are severely limited Antonelli et al., 2020;Cheek et al., 2020): the current knowledge of Uzbekistan fungal biodiversity status and even a rough estimate of the number of fungal species in countries of Central Asia is unavailable. This knowledge gap has significantly impeded understanding the role of the region in biogeographic history of Asia and prevented conservation efforts in the region.
Fungi are essential components of ecosystems and are both directly and indirectly important for human cultures. Various fungal species are key symbionts of trees enabling the survival of the latter in the arid areas (Varma, 1995;Stutz et al., 2000). Fungal names used in other regional floras have often been applied to fungi in Uzbekistan. However, the Uzbek fungi often represent new, unrelated species as was shown for Uzbekistan ascomycetous microfungi Gafforov, 2001, 2002;Gafforov and Hoshino, 2015;Gafforov, 2002Gafforov, , 2010Gafforov, , 2015Gafforov, , 2016aGafforov and Rakhimov, 2017;Gafforov et al., 2019;Wanasinghe et al., 2017Wanasinghe et al., , 2018aSamarakoon et al., 2018;Pem et al., 2018Pem et al., , 2019aHyde et al., 2019Hyde et al., , 2020Yuan et al., 2020). Basidiomycetous fungi have received even less attention than ascomycetous microfungi (Gafforov, 2014;Gafforov et al., 2014. Among the basidiomycetous macrofungi, especially those with poroid fertile surface of fruiting bodies (poroid fungi) and corticioid fertile surface (corticioid fungi) play several essential roles in forest ecosystems (Swift, 1982). Most of these fungi are saprobes causing brown or white wood rot, whereas some of them form ectomycorrhizae with woody plants. Therefore, they play an important function in nutrient cycling and soil formation (Soudzilovskaia et al., 2019). Some of them are also known to be serious pathogenic disease agents of ecologically and economically important coniferous and deciduous woody plants. Regardless of the relationship, wood-inhabiting basidiomycetous fungi are often treated as a single research object by both taxonomists and ecologists.
The first mycological investigations on wood-inhabiting fungi in Uzbekistan were started by Sinadskiy and Bondartseva in 1950, who reported 21 polypore species Bodartseva, 1956, 1960;Kleyner, 1958;Panfilova and Gaponenko, 1963;Gaponenko, 1965;). The first study specifically in state reserves of Uzbekistan listed 71 polypore species . In the study of macrofungi of Fergana valley (Andijan, Fergana and Namangan Provinces), Tashkent Province, 25 species of poroid and corticioid fungi were reported . However, the fungal species recorded in these studies were identified solely by morphological characters and no specimen was preserved, which makes the reassessment of taxonomic affiliation of these records impossible.
Recent developments in DNA sequencing have revolutionized identification and systematics of fungi. This has rapidly advanced the mycological communities' ability to document fungal biodiversity, distribution, ecological preferences, and biogeographic history (e.g., Hattori et al., 2012;Ovaskainen et al., 2013;Tsykun et al., 2013;Tedersoo et al., 2014). DNA barcodes can facilitate taxonomic research by increasing the ability to matching individuals regardless of the fruiting body, identifying specimens with morphological diagnostic characters either subtle, difficult to visualize, or absent, as well as reassessing intraspecific polymorphisms. With the aid of DNA sequences, research on the wood-inhabiting basidiomycetous fungi during the last decade has yielded some species previously unknown in Uzbekistan, as well as some species new to science (Gafforov, 2014;Gafforov et al., 2014Yuan et al., 2017Yuan et al., , 2020Kan et al., 2017). Moreover, the first fungal checklist of the corticioid genus Hyphodontia from Central Asia was published . However, despite these steps forward, comprehensive information of the wood-inhabiting poroid and corticioid fungi is still unavailable in Uzbekistan.
On the basis of our own collections, literatures, and herbarium data reassessments, the present study aimed to recognize species diversity of wood-inhabiting poroid and corticioid fungi (plus similar taxa such as Merismodes, Phellodon and Sarcodon) in Uzbekistan from morphological and, where possible, phylogenetic perspectives, and also to provide comprehensive annotations for these species including host, substratum, distribution, and occurring frequency.

Vegetation and Climate of the Study Area
The Uzbekistan territory falls in the flora of Central Asian botanical region within the larger temperate Asia floral geographic region according to the World Geographical Scheme for Recording Plant Distributions' system (Brummitt, 2001). The main ecological forest types in Uzbekistan are mountain, desert, and flood-plain forests (Figure 1). The majority of Uzbekistan forests are xerophytic open woodlands of deciduous trees and shrubs, constituting about 7.3% of the territory (Botman, 2009). These forests play an important role in the protection and prevention from environmental degradation, particularly land degradation and natural disasters, and also in the conservation of biodiversity and preservation of water quality.
Uzbekistan has a continental climate with hot and dry summers and cold winters. Summer temperature often surpasses 40 • C (104 • F), and winter average temperature is about −2 • C (28 • F) but may fall as low as −40 • C (−40 • F). Most parts of the country are arid with average annual rainfall amounting to between 100 and 200 mm (3.9 and 7.9 in) and occurring mostly in winter and spring. Between July and September, little precipitation falls, essentially stopping the growth of vegetation during that period (Klein Tank et al., 2006;Lioubimtseva and Henebry, 2009).

Specimen Assembly
A total of 286 specimens of wood-inhabiting poroid and corticoid were examined. This includes 101 specimens from Mycological Herbarium of Estonian University of Life Sciences, Tartu, Estonia (TAAM); 3 specimens from Tashkent Mycological Herbarium, Institute of Botany of the Academy of Sciences of Uzbekistan, Tashkent (TASM); and 185 specimens from our own field surveys, which are deposited in TASM. Our own specimens were recently collected from Tashkent Botanical Garden (Tashkent city), Tashkent Province (Ugam-Chatkal State Nature National Park in Western Tien Shan Mountain), Jizzakh Province (Zaamin National Nature Park, Zaamin State Reserve in Turkestan range and Nurata State Reserve in Nurata range of Pamir-Alay), Surxondaryo Province (Baysun and Husar ranges in Pamir-Alay Mountains), and Fergana Valley (Namangan Province) (Figure 2). In addition, we reviewed 504 records of Uzbekistan fungi published between 1950 and 2020. FIGURE 2 | Map of (a) Uzbekistan labeled with five principal collecting areas shown in panels (b-f). The background map in panels (b-f) is the combination of bands 1, 4, 3 displays and R, G, B surface reflectance image using 500-m MODIS data (MODS09A1) acquired in July 2019 over Uzbekistan (by Yu Zhou).

Morphological Study
Morphological characters were described based on fresh and dried fruiting bodies. Microscopic characters of fruiting bodies were observed on dried specimens at a magnification up to 1000 × with a Leica DM 1000 (Tokyo, Japan) microscopes in 5% aqueous KOH plus 1% phloxine, Melzer's reagent for amyloid or dextrinoid reactions, cotton blue in lactic acid for cyanophily, and 1% aqueous cresyl blue for metachromatism (Hawksworth et al., 1995). Macromorphological characters of fruiting bodies and hymenophores were observed under a Leica M165 FC stereomicroscope. Scientific names, both of the fungi and the host plants, were checked for potential synonyms in the databases Index Fungorum (2020) and ThePlantList (2013), respectively. Species whose taxonomic placement is not established are listed under incertae sedis.

DNA Extraction, Amplification, and Sequencing
Genomic DNA was extracted from the dried basidiocarps of herbarium materials using DNeasy Plant Mini Kit (Qiagen, Valencia, CA, United States), QIAamp DNA Micro Kit (Qiagen), and the Extract-N-Amp Plant PCR Kit (Sigma-Aldrich, St. Louis, MO, United States), following protocols from the manufacturers, and was diluted as a template for subsequent amplification. PCR amplification targeted the internal transcribed spacer (ITS) region of the ribosomal RNA gene (rRNA), the universal DNA barcode for identification of fungi (Schoch et al., 2012), and the nuclear large ribosomal subunit (nLSU) region. Amplification was carried out using the fungal-specific primer sets ITS1F/ITS4b (Gardes and Bruns, 1996) and ITS1/ITS4 (White et al., 1990) for the ITS region and LR0R and LR5 for the nLSU region (Vilgalys and Hester, 1990;Rehner and Samuels, 1994). Purified PCR products were sequenced using DNA ABI 3730 XL automated sequencers (Applied Biosystems) by Macrogen Inc. (Seoul, Korea), by Eurofins Genomics (Ebersberg, Germany), and by the Beijing Genomics Institute (Beijing, China). All newly generated sequences of poroid and corticoid species from Uzbekistan were submitted to GenBank ( Table 1).

Phylogenetic Analyses
After a preliminary BLAST search, 40 sequences related to those from Uzbekistan specimens were downloaded from GenBank to assist species identification ( Table 1). The datasets of ITS and nLSU regions were separately aligned using MAFFT 7.110 (Katoh and Standley, 2013) under the G-INI-i option (Katoh et al., 2005) and then the two alignments were concatenated. The concatenated alignment, deposited in TreeBASE 1 (accession number S26575), was subjected to an estimation of the bestfit evolutionary model using jModelTest (Guindon and Gascuel, 2003;Posada, 2008) with calculation under Akaike information criterion. Following this model, maximum likelihood (ML) and Bayesian inference (BI) methods were employed for phylogenetic analyses. The ML method was conducted using raxmlGUI 1.2 (Stamatakis, 2006;Silvestro and Michalak, 2012) with calculation of bootstrap (BS) replicates under the auto FC option (Pattengale et al., 2010). The BI method was conducted using MrBayes 3.2 (Ronquist et al., 2012). Two independent runs were employed. Each run had four chains and started from random trees. Trees were sampled every 1000th generation, of which the first 25% were removed and the other 75% were used for constructing a 50% majority consensus tree and calculating Bayesian posterior probabilities (BPPs). Tracer 1.5 2 was used to determine chain convergence. iTOL was used to visualize the tree to a circular form (Letunic and Bork, 2019).

GBIF Occurrence Dataset and Checklist Preparation
The occurrence data of wood-inhabiting poroid and corticioid fungi was extracted from 504 records in 19 publications as well as 185 records of our own recent collections in field surveys and 101 herbarium specimens from TAAM and TASM. All but collection data from TAAM (which are already displayed in GBIF) were formatted according to the Darwin Core Standard 3 and published as an occurrence dataset (Gafforov and Ordynets, 2020, 4 alternative identifier 5 ). When compiling the annotated species checklist for this paper, for the sake of conciseness, all occurrence records were linked to 50 localities that are listed in the study.

GIS Data Processing
A point distribution map of fungal orders was produced using the ArcGIS 10.7 desktop software (ArcGISDesktop,2020).
A GPS navigation device and Google Earth software 6 (2020) were used for geo-referencing all available occurrence data of wood-inhabiting poroid and corticioid fungi in the study sites. A WGS84 geographic coordinate system was used as a reference datum. The land cover data were adapted from the 500m Moderate Resolution Imaging Spectroradiometer (MODIS) land cover product (MCD12Q1; Friedl et al., 2002) which has 17 IGBP classes, including water, evergreen needleleaf forests (ENF), evergreen broadleaf forests (EBF), deciduous needleleaf forests (DNF), deciduous broadleaf forests (DBF), mixed forests (MF), closed shrublands (CSH), open shrublands (OSH), woody savannas (WSA), savannas (SAV), grasslands (GRA), permanent wetlands, cropland (CRO), urban and built-up, cropland and natural vegetation mosaics (CNM), snow and ice, and barren. Considering the spatial distribution of irrigated and cultivated croplands, we further integrated these two classes from Klein et al. (2012). Data for roads, rivers, lake centerlines, and country boundaries were downloaded from the Natural Earth database (Natural Earth, 2020).

Phylogenetic Placement of Collections of Poroid and Corticoid Fungi From Uzbekistan
In addition to morphological characters, DNA sequences were used to identify certain specimens. A total of 114 ITS and 85 LSU sequences from 138 specimens representing 40 species were newly generated for this study, and submitted to GenBank ( Table 1). The alignment used for phylogenetic analysis included 178 collections ( Table 1). The best-fit evolutionary model for this alignment was estimated as GTR + I + G. In the ML method, the BS search stopped after 250 replicates. In the BI method, all chains were converged after 6 million generations, where the average standard deviation of split frequencies is 0.006815, the estimated sample sizes of all parameters are above 700, and the potential scale reduction factor approaches 1.0. Both phylogenetic methods generated congruent topologies in main lineages, and thus only the topology from the ML method is visualized in a circle form with BS and BPP at the nodes (Figure 3). From a phylogenetic perspective, 36 species were recovered and four potential new lineages representing members of Hyphoderma, Neoantrodiella, Phlebia, and Vuilleminia were identified from the newly sequenced specimens.

Species Diversity of Wood-Inhabiting Poroid and Corticoid Fungi in Uzbekistan
Taking literature information and morphological and phylogenetic evidence into consideration, we report 153 species of wood-inhabiting poroid and corticoid fungi including 149 described species and four single-specimen undescribed lineages belonging to 10 orders (Agaricales, Atheliales, Cantharellales, Corticiales, Gloeophyllales, Hymenochaetales, Russulales,     64 species or 41.8%, and the other genera have one to two species ( Table 2).

Annotated Checklist of Wood-Inhabiting Poroid and Corticioid Species in Uzbekistan
The checklist of 153 species of wood-inhabiting poroid and corticioid fungi is arranged alphabetically by orders, family, and species. The currency sign (¤) indicates potentially new species to science and asterisk ( * ) denotes new fungal records to Central Asia and thus to Uzbekistan, while the new fungal records to Uzbekistan but not to Central Asia is indicated by a number sign (#). A filled circle (•) means identification was DNA-assisted. Short notes are provided for some taxa. Photos of basidiocarps in situ are shown for some species (Figures 5-7).
Note: In TAAM, this specimen was originally labeled as Phlebia aurea.
Note: This species is widespread and causes damage to Acer tataricum subsp. semenovii trees in Tien Shan Mountain.

Substrate Preferences of Wood-Inhabiting Poroid and Corticioid Species in Uzbekistan
In this study, poroid and corticoid fungal species were found on 100 woody plant species belonging to 23 families and 42 genera. One hundred wood-inhabiting species (accounting for 65.3% of the total wood-inhabiting poroid and corticoid species of Uzbekistan) were recorded exclusively on deciduous wood, 33 species (21.6%) were found exclusively on coniferous wood, and 5 species were recorded as inhabiting both groups of woody plants (Figure 8). The hosts were not determined for the remaining 15 species. These wood-inhabiting fungi were most frequently found on hosts belonging to Salicaceae (72 fungal species), Pinaceae (51), Rosaceae (48), Fagaceae (31), Juglandaceae (30), Betulaceae (25), Cupressaceae (16), Sapindaceae (16), and Ulmaceae and Oleaceae (each 11). Collectively, these families host about 70% of fungal species present in the study area; other plant families host one to nine species ( Table 3).

The Distribution Range and Niches of Wood-Inhabiting Poroid and Corticioid Fungi in Uzbekistan
By importing all known records of wood-inhabiting poroid and corticioid fungi in Uzbekistan into ArcGIS, a distribution GIS map of wood-inhabiting poroid and corticoid species in Uzbekistan was produced (Figure 11). The distribution of all records in the whole study area was first mapped (Figure 11a), and then five subareas where fungal records are relatively dense were presented (Figures 11b-f). Fungal species were most commonly collected in subarea f with 445 records in Western Tien Shan Mountains in Tashkent province, followed by subarea b with 142 records in Pamir-Alay Mountain in Samarkand, Qashqadaryo, and Surkhandaryo Provinces of Central and Southern Uzbekistan. Subareas c, e, and d have 58, 51, and 46 records, respectively, in Turkestan, Nurata, Kurama, and Fergana ranges in Pamir Alay and Western Tien Shan Mountains in Navoi, Jizzakh, and Fergana valley of Uzbekistan (Figures 11c-e).

DISCUSSION
In this study, we compiled for the first time the species diversity of wood-inhabiting poroid and corticioid fungi in Uzbekistan. Comprehensive information of these species is provided, including taxonomic diversity, substrate preference, and distribution of geographic and landscape position, on the basis of 790 fungal records collected from 1950 to 2020.
A total of 153 wood-inhabiting poroid and corticioid species, belonging to 10 orders, 26 families, and 97 genera, were confirmed to be present mainly based on literature references, morphological examinations, and also on phylogenetic analysis wherever possible. Of these 153 species, 19 are new for mycobiota to Central Asia and 31 are reported for the first time in Uzbekistan. In addition, four taxa that may be new to science were discovered and must be examined further. The fungal diversity reported here for Uzbekistan is much lower than that in other regions where the diversity of wood-inhabiting poroid and corticoid fungi is well explored. For example, 1210 woodinhabiting poroid and corticioid species, including ecologically similar hydnoid fungi, are recorded in China (Dai, 2011(Dai, , 2012. Also, the number of wood-inhabiting poroid fungi recorded is 492 and 394 in North America and Europe, respectively (Ryvarden and Melo, 2014;Zhou et al., 2016). The low species number in Uzbekistan is partly due to the relatively small area, but also due to the lack of systematic field surveys and thorough identification with the aid of molecular sequencing. Few scientists   study the ecologically important fungi of Uzbekistan. Although this report is the most comprehensive study of diversity of woodinhabiting poroid and corticiod fungi in Uzbekistan today, it must be considered provisional. In contrast, tens of taxonomists have jointly contributed records of hundreds of (mainly new) wood-inhabiting poroid and corticioid species in China since the publications of Dai (2011Dai ( , 2012. Therefore, even if we have reported the most comprehensive diversity of woodinhabiting poroid and corticioid fungi in Uzbekistan to date, the current knowledge has to be considered as a provisional species checklist to be complemented. It is known that higher diversity of plant species results in a higher diversity of associated fungal species (Küffer and Senn-Irlet, 2005;Yamashita et al., 2010;Hawksworth and Lücking, 2017). Uzbekistan, with its mountainous landscape, is characterized by a high diversity of trees and shrubs, perhaps 500-600 species (Eastwood et al., 2009). Therefore, maybe more taxa of wood-inhabiting poroid and corticioid species, including new and even endemic species, still await to be revealed from Uzbekistan Yuan et al., 2020).
Most of the reported wood-inhabiting poroid and corticioid fungi in Uzbekistan are wood decomposers, FIGURE 11 | Spatial pattern of wood-inhabiting poroid and corticioid fungi at an order level based on 790 fungal records in (a) our study area, and five principal collecting areas shown zoom-in views in panels (b-f).
which release matter and energy to the ecological system. These saprophytic species possess powerful enzymes, which can effectively degrade lignocellulose (Riley et al., 2014). In the current Uzbekistan mycota, several species in Trametes are considered to have potential biotechnological applications (Kneževič et al., 2013;Wang and Chen, 2019;Yang et al., 2020).
Although the resource recycling functions are generally considered beneficial to trees, forests, and humans, some of the wood-inhabiting poroid and corticioid fungi studied inhabit living trees as forest pathogens. According to previous studies (Kleyner, 1958;Sinadskiy and Bodartseva, 1960;Panfilova and Gaponenko, 1963;Gafforov, 2014;Gafforov et al., 2014) and our field observations, Inonotus hispidus, Bjerkandera adusta, Cerrena unicolor, Lentinus tigrinus, Fomes fomentarius, Laetiporus sulphureus, Phylloporia yuchengii and Ganoderma applanatum, Aurantiporus fissilis, and some species from the genera Trametes and Phellinus can cause root rot disease. In addition, moreover, Cerrena unicolor also produces a stem canker of living Acer semenovii, Juglans regia, Crataegus pseudoheterophylla subsp. Turkestanica, and Celtis australis subsp. caucasica. Noteworthily, Inonotus hispidus is widespread in the walnut-fruit forests of Uzbekistan and damages up to 4% of the trees of Juglans regia and Malus sieversii trees in Baysun and Turkestan ranges of Pamir Alay Mountains (unpublished data Gafforov); Phellinus igniarius was observed both as a parasite and saprophyte of deciduous trees from the genera Juglans, Salix, and Acer in Ugam-Chatkal Natural State Park and Zaamin and Hissar State Reserve. The forest diseases caused by these wood-inhabiting poroid and corticioid fungi and the corresponding economic loss should be considered by relevant management departments.
In addition, some macrofungi including wood-inhabiting poroid and corticioid species are important edible and medicinal fungi (Wu et al., 2019;Zhou et al., 2020). Some poroid species known from Uzbekistan are recognized as valuable medicinal fungi, while Grifola frondosa, Laetiporus sulphureus, and Sarcodon imbricatus are important edible fungi. Cultivation of wood-inhabiting fungi is an important agricultural industry worldwide, especially in East Asia. Several medicinal and edible species, like Ganoderma spp. and Auricularia spp. in mainland China, Taiwanofungus in Taiwan, China, and Sanghuangporus spp. in South Korea, have huge economic value. In China, edible and medicinal fungi are the fifth largest crop industry (Dong et al., 2017). Industrial development of suitable endemic woodinhabiting poroid and corticioid fungi will undoubtfully benefit the Uzbekistan economy. Uzbekistan materials must be directly studied for utilization of these fungal resources. For this purpose, strains of wood-inhabiting poroid and corticioid fungi firstly need to be isolated and preserved in public organizations.
The proportion of wood-inhabiting poroid and corticioid fungi found on different hosts differs in Uzbekistan from that in comparable temperate and warm temperate forest zones of China (Zhou et al., 2011). Compared with the proportions in temperate and warm temperate forest zone (Zhou et al., 2011), the proportion of wood-inhabiting poroid and corticioid species in Uzbekistan found on deciduous wood (72.46%) is similar, but the proportion on coniferous wood is much higher (23.91%) and that on both groups of wood is much lower (3.62%). The differences in the proportions on coniferous wood and both groups of wood compared to the Chinese case may be either the real status in Uzbekistan or a misleading failure to observe that some species recorded exclusively on coniferous wood do actually occur also on deciduous wood. Many more field surveys are needed to clarify this issue.
Among the 100 woody plant species belonging to 23 families and 42 genera recorded as hosts for wood-inhabiting poroid and corticioid species, Salicaceae, Pinaceae, and Rosaceae are the most favored, and Populus, Quercus, Juglans, and Salix are the most favored host genera.
To well understand the spatial patterns of wood-inhabiting poroid and corticioid fungi, their distributions associated with geography and landscapes were visualized using GIS maps (Figure 11). Wood-inhabiting poroid and corticioid species in Uzbekistan are distributed mostly in the regions of open shrublands and grasslands, and rarely in various kinds of forests. This distribution pattern is opposite to the natural habitats of such fungi as reported in previous studies. For example, Zhou and Dai (2012) reported that reserved forest with amounts of woody substrates for the growth of wood-inhabiting poroid fungi has significantly higher polypore diversity than unprotected forest. Moreover, normally, forests have higher species diversity of woody plants, which result in higher diversity of wood-inhabiting poroid fungi . This unusual phenomenon in Uzbekistan might be caused by a lower proportion of field surveys carried out in virginal forests due to difficult access. Therefore, more efforts should be made to reveal the diversity of wood-inhabiting poroid and corticioid fungi in the most primeval forests.
The two fungal orders with highest record diversity, viz., Polyporales and Hymenochaetales, are common in the whole studied area (Figure 11a). This reflects that geography and landscape factors do not have significant effects on the distribution of these two fungal orders. These two fungal orders have high species diversity ( Table 2), resulting from a wide adaption to the environment. Species diversity of these two orders are also highest in other regions of the world (Dai, 2012;Ryvarden and Melo, 2014;Zhou et al., 2016). Russulales, the order with the third highest recorded diversity, also occurs in all five subareas, but mainly in the subarea f, viz., Western Tien Shan Mountains in Tashkent region (Figure 11f). Other orders and the species without a confirmed position at the order level are present only in small areas. Such species may be sensitive to environmental changes. So, to sustain species diversity of wood-inhabiting poroid and corticioid fungi, special attention should be paid to protecting their habitats. Using the GIS data, the potential future distribution of certain important (biotechnological, pathogenic, medicinal, and edible) woodinhabiting poroid and corticioid species could be predicted. Similar studies have been performed on some wood-inhabiting poroid and corticioid species worldwide (Yuan et al., 2015;Elias et al., 2020). Generally, knowledge of species diversity and occurrence in an area is a baseline for benefiting from ecosystem services, monitoring environmental changes, and implementing conservation actions Hibbett et al., 2007Hibbett et al., , 2011Brock et al., 2009;Hyde et al., 2013;Osmundson et al., 2013;Truong et al., 2017). Therefore, the current GIS data are important for management and utilization of wood-inhabiting poroid and corticioid fungi in Uzbekistan.
In conclusion, this study provides the first comprehensive, thoroughly annotated checklist of species diversity of woodinhabiting poroid and corticioid fungi in Uzbekistan. These species are ecologically and economically important as decomposers, pathogens, and sources of food and medicines. Beyond local scale, these data are also crucial as a supplement of the global knowledge of wood-inhabiting poroid and corticioid fungi and for elucidating the evolutionary history of wood-inhabiting poroid and corticioid fungi worldwide. More importantly, the current project exploring wood-inhabiting poroid and corticioid fungi in a less studied country may initiate similar explorations in other Central Asian countries and also other regions worldwide, which will largely fulfill the knowledge gap of wood-inhabiting poroid and corticioid fungi in certain rarely studied regions.

DATA AVAILABILITY STATEMENT
The datasets presented in this study can be found in online repositories. The names of the repository/repositories and accession number(s) can be found in the article/ supplementary material.

AUTHOR CONTRIBUTIONS
YG and MY collected fungal specimens and performed DNA lab work. YG and AO were responsible for morphological identification and management of collection data. L-WZ and YG performed the molecular phylogenetic analyses. YZ mapped the fungal taxa. YG, AO, and L-WZ drafted the manuscript. EL, AG, DS, LP, and LC improved and revised it. All authors have read the final manuscript version and approved it. All authors contributed to the article and approved the submitted version.  (Grant No. 190136/2013-8). L-WZ thanks the financial support from the Youth Innovation Promotion Association of the Chinese Academy of Sciences (No. 2017240).