Hardwood Tree Species Research Articles

Genome sequence resources from three isolates of the apple canker pathogen Neonectria ditissima infecting forest trees

Neonectria ditissima is a generalist ascomycete plant pathogen causing canker diseases on a variety of hardwood tree species and can cross-infect many of them. The fungus enters the plants through wounds throughout the year. N. ditissima is considered a major threat to apple production responsible for the fruit tree canker disease which damages trees and causes rotting of fruits in storage. Nearby forests and shelter belts can serve as source of inoculum for well-managed apple orchards. Thus, knowledge about the N. ditissima isolates infecting different host species is essential for designing integrated pest management strategies. Here, we describe the genomes of three N. ditissima isolates, Nd_iso34, Nd_iso35, and Nd_iso36, infecting European beech, American tulip tree, and American beech, respectively. We obtained genome assemblies of ca. 45 megabases for all isolates, covering 94% of the N. ditissima reference annotation, and 97% of the universal single-copy orthologs (BUSCOs). We conclude that these genome assemblies are a highly relevant resource considering the scarcity of genomic data available for N. ditissima.

Wood Quality of Pendulate Oak on Post-Agricultural Land: A Case Study Based on Physico-Mechanical and Anatomical Properties

Oak is one of the most economically important hardwood tree species in Europe, and its prevalence will increase due to progressing global climate change, according to predictive models. With the increasing demand for timber and with the need for a balance between carbon emissions and sequestration, it is essential to address the afforestation of agricultural land. Therefore, this research aimed to investigate the physico-mechanical properties and anatomical structure of pendulate oak (Quercus robur L.) wood—specifically focusing on the trunk’s cross-section—in post-agricultural areas compared with the forest land in the western part of Poland. Wood density, bending strength, modulus of elasticity, and other parameters were analyzed from 1626 wood samples. The analysis of physico-mechanical properties reveals that, historically, agricultural land use has an almost negligible impact on wood quality. Despite significant differences in small vessel diameter and fiber length favoring trees from post-agricultural land, the physico-mechanical properties remain consistent. Large vessel measurements show comparable diameter and length in both land types. These findings suggest that post-agricultural land can serve as an effective alternative for high-quality pendulate oak wood production for industrial purposes. However, wood from post-agricultural land may exhibit a decrease in modulus of rupture by over 30% and potentially lower density above the trunk’s halfway point. This observation hints at the fact that oak trees in post-agricultural areas could be cultivated in shorter rotation periods compared to forest land.

The outbreak of teak leaf blight disease caused by Alternaria alternata in the semi‐arid Bundelkhand region of India

AbstractTectona grandis is a vital hardwood tree species with substantial industrial and economic importance. From 2020 to 2021, an unusual leaf blight disease was observed in T. grandis saplings planted in the Nursery of the Central Agroforestry Research Institute (CAFRI), Jhansi, India. Disease incidence was recorded as 50%–70% with 40%–82% severity over two consecutive years on over 1000 saplings. The leaf blight disease was extensive, leading to defoliation of young leaves and mortality of teak saplings in the nursery. The pathogen was identified as Alternaria alternata following standard laboratory procedures and sequence analysis of the internal transcribed spacer (ITS) region of the ribosomal RNA (rRNA). The pathogenicity of two isolates, A. alternata TgAa1 and TgAa2, was proven under greenhouse conditions. Phylogenetic analysis revealed the close association of TgAa1 and TgAa2 with other pathogenic A. alternata strains in the NCBI database. A. alternata is considered a severe foliar pathogen, known to cause leaf spot and leaf blight diseases in many annual and perennial plant species. Correct diagnosis and prevention are emphasized to contain the spread of teak leaf blight to other regions in India. This is the first report of A. alternata causing Tectona grandis leaf blight in the Bundelkhand region of India.

Chemical reagent for detecting tension wood in selected tree species

Reaction wood is a wood defect arising during the growth of the tree in the part of the trunk that is under tension (hardwood tree species) or compression (coniferous tree species). Beech (Fagus sylvatica L.) tension wood has different anatomical and chemical characteristics than normal (opposite) wood. The difference in density is conditioned by the percentage of the gelatinous layer (G-layer). Fibre cells in reaction beech wood have a different cell wall structure and a different chemical composition. Tension wood cannot be detected by the naked eye. It is only possible to assume its occurrence based on the macroscopic characteristics of the logs, such as a woolly surface, taper or eccentric pith, and so forth. However, these are imprecise and unreliable methods that have minimal effectiveness, especially when shortening the length of the log for cut-outs. This study aimed to create a unique chemical reagent for the detection of tension wood in logs and timber and wood products immediately. The present research can contribute to the mitigation of flaws resulting from the reaction of wood in timber production while addressing noticeable constraints in manufacturing, such as energy resources and the availability of wood raw materials. This can be achieved through the efficient identification of reaction wood in materials. The colour change is only temporary and will fade over time. After the chemical reagent has dried on the surface, the surface can be milled. The colour change extends to a depth of approx. of 3 to 5 mm.

CentralBark Image Dataset and Tree Species Classification Using Deep Learning

The task of tree species classification through deep learning has been challenging for the forestry community, and the lack of standardized datasets has hindered further progress. Our work presents a solution in the form of a large bark image dataset called CentralBark, which enhances the deep learning-based tree species classification. Additionally, we have laid out an efficient and repeatable data collection protocol to assist future works in an organized manner. The dataset contains images of 25 central hardwood and Appalachian region tree species, with over 19,000 images of varying diameters, light, and moisture conditions. We tested 25 species: elm, oak, American basswood, American beech, American elm, American sycamore, bitternut hickory, black cherry, black locust, black oak, black walnut, eastern cottonwood, hackberry, honey locust, northern red oak, Ohio buckeye, Osage-orange, pignut hickory, sassafras, shagbark hickory silver maple, slippery elm, sugar maple, sweetgum, white ash, white oak, and yellow poplar. Our experiment involved testing three different models to assess the feasibility of species classification using unaltered and uncropped images during the species-classification training process. We achieved an overall accuracy of 83.21% using the EfficientNet-b3 model, which was the best of the three models (EfficientNet-b3, ResNet-50, and MobileNet-V3-small), and an average accuracy of 80.23%.

Public Attitudes towards Forest Pest Damage Cost and Future Control Extent: A Case Study from Two Cities of Pakistan

Infestations of pests are perhaps an anthropogenic catastrophe for trees. Aeolesthes sarta (Sart longhorned beetle—SLB) is one of the most severe pests that cause serious damage to a number of hardwood tree species, i.e., Populus, Salix, Acer, Juglans, and Malus. To investigate people’s attitudes towards pest damage cost and future control extent of SLB, a door-to-door method was adopted to survey two major cities (Quetta—QU and Peshawar—PE) of the northwestern region of Pakistan where this pest has caused severe damage. Respondents were asked about SLB pest knowledge, pest damage costs, preferences for control choices, and program extent. According to respondents, more trees (181 ± 1.20 trees/ha/annum) were damaged in QU compared to PE. Populus spp. was the dominant tree genre that attacked and damaged the most. Around 85% of respondents from both cities stated the pest damage cost was calculated as high for QU (480,840.80 ± 4716.94$/annum) compared to PE. Respondents in both locations strongly supported (more than 82%) biological control of future SLB outbreaks. They all agreed that protecting ecologically vulnerable places and wildlife habitats should be the primary priority in a future SLB outbreak. Respondents from both cities who preferred to protect more land area in future SLB outbreaks were calculated to be high for QU (61%) compared to PE (58%). However, city variations in opinions regarding forest-type priority that should be protected and control options were observed. Socio-demographic characteristics were discovered to impact pest damage cost positively, as well as preferred SLB control extent. The findings of this study can help policymakers and forest managers develop publicly permissible pest control plans and make more accurate predictions about future pest outbreaks.

Heart Rot Disease of Walnut Caused by Nothophoma juglandis sp. nov. and Its Endophytic Biocontrol Agent.

English walnut (Juglans regia L.) is an economically important hardwood tree species cultivated worldwide. Walnut heart rot disease leading to heartwood decay of trees has been frequently observed in a number of plantations in China. To identify the causal agent, 29 diseased stem samples were collected from walnut plantations in Beijing, and 54 fungal isolates were obtained. Koch's postulates were developed, and the results showed that Nothophoma juglandis, a species new to science, was the causal agent of walnut heart rot disease. Granulobasidium vellereum, a notable biocontrol agent, was coisolated with N. juglandis. An antagonistic assay on dual culture and walnut stems (both in the field and detached branches) proved that G. vellereum acted as a potential biocontrol agent against N. juglandis, as it could significantly inhibit the expansion of N. juglandis. The optimal temperature for mycelial growth and pathogenicity of N. juglandis was 26.6 and 27.0°C, respectively, which frequently occur in the summer of the walnut-growing regions in China.

Functional traits to predict financial value of enrichment planting in degraded tropical forests

Demand for tropical timber is expected to rise due to an increased global need for sustainable renewable materials. However, sustainable tropical timber production remains a challenge for the global wood product supply chain, especially for high-value tropical hardwoods. Restoration of degraded lands through enrichment planting of native hardwood species could provide a solution, but the financial viability of using native tropical tree species remains largely unknown. We evaluated the financial viability of 22 hardwood tree species native to northern Borneo in enrichment plantings of a degraded forest in Sabah, Malaysia. We investigated how the species’ financial value, expressed as an internal rate of return (IRR) based on land expectation value, varied with their functional trait composition. We found that high financial value was positively correlated with trait values associated with a conservative growth strategy, i.e., financial value was negatively correlated with leaf calcium, magnesium, and nitrogen content, as well as with leaf pH and specific leaf area. Trees with these traits showed a high IRR, partly explained by relatively fast growth and high survival rates. For the most economically promising species, Shorea macrophylla, we estimated that enrichment planting for forest restoration could reach IRRs up to 7.8%. Our results showed that enrichment planting for high-value hardwood production in degraded forests can be financially viable, with variation among species, and that various traits associated with a more conservative growth strategy were linked to high financial value.

Environmental Factors Affecting Volume Growth of Yellow Poplar Plantations in South Korea

South Korean forests need hardwood tree species that can produce timber, as global warming progresses and the habitats of conifers dwindle. For the past 30 years, exotic yellow poplar (Liriodendron tulipifera) has been planted to replace some of the pine-dominated forests, as there is a lack of native hardwood tree species that produce large and good quality timber. However, yellow poplar growth has varied among planting sites across the country. We studied how environmental factors affect the growth of 49 stands of yellow poplar trees, with 945 dominant trees across 129 plots. To identify the optimal conditions for yellow poplar growth, we assessed 28 environmental variables, including geographic, climatic, topographic, and soil properties, for their correlation with volume growth. We estimated the optimal conditions for yellow poplar growth by averaging the values of the variables for the top five performing stands. To calculate the relative distance of any stand from the optimal conditions, we divided the difference between the stand’s values for the environmental variables and the optimal conditions by the standard deviation of those variables. We then calculated Spearman rank correlation coefficients between these distances and volume growth rankings. Wind exposure (WE), growing season temperature (GT), Latitude (LN), soil phosphorus pentoxide (P2O5) content, low extreme temperature during January and February (LT), and spring humidity (SH) were the most important environmental factors governing growing sites for yellow poplar in Korea, with WE being the most critical. Some variables showed synergistic effects and correlated slightly more strongly with volume growth when combined with the WE variable. Our study provides crucial insights for optimizing plantation management and site selection in non-native ranges, enhancing overall success in establishing yellow poplar plantations in South Korea.

FirstReportofFusariumsolaniassociatedwithTwigCankerofEnglishWalnut(JuglansregiaL.)inXinjiang, China.

English walnut (Juglans regia L.) is a perennial deciduous fruit tree, and an economically important hardwood tree species cultivated worldwide. As one of the important economic crops, English walnut is also widely cultivated in Xinjiang. In September 2019, twig canker symptoms were observed on English walnut in several orchards, with approximately 15% to 40% disease incidence in southern Xinjiang region (79º95'E, 40º37'N). The branch lesions were long oval, concave, and black to brown. Leaves of the affected branches turned yellow and the branches eventually died. Infected twigs were collected from an infected tree in an orchard. Symptomatic tissue from the margins of cankers was surface disinfested with 75% ethanol for 60 s, rinsed 3 times with sterile water, and then incubated on potato dextrose agar medium (PDA) at 25 ℃ under a 12-hr photoperiod in Light incubator for 7 days. Seven fungal isolates showing similar morphology were obtained from the symptomatic tissue. All the fungal cultures had a pink-white color with loose, cottony mycelium, and the underside of the colonies were light brown. Macroconidia were slightly curved, with one to six septa, both ends were slightly sharp, and they measured 22.8 to 38.5 × 3.5 to 6.7 μm (27.4 ± 0.6 × 4.2 ± 0.3 μm, n=50). Microconidia were oval, hyaline, zero to one septa, measuring 4.5 to 9.6 × 1.8 to 2.3 μm (6.8 ± 0.3 × 2.1 ± 0.1 μm, n=50). According to the morphological characteristics, the seven isolates were identified as a member of the Fusarium solani species complex (Summerell et al. 2003). Genomic DNA was extracted from the representative isolate HSANTUAN2019-1, and the internal transcribed spacer (ITS) region, the translation elongation factor 1-alpha (TEF) were amplified with the primer pairs ITS1/ITS4 (White et al. 1990) and EF1-F/EF2-R (O' Donnell et al. 2010), respectively. The sequences submitted to GenBank (accession nos. OP271472 for ITS, OP293104 for TEF) showed high similarity with the reference sequences of F. solani (ITS, OL691083 [100%]; TEF, HE647960 [99.86%]). Pathogenicity of the seven isolates were assessed on 1-year-old branches of English walnut in the field. Healthy branches (40) were wounded with a sterilized hole punch, and then inoculated with isodiametric mycelial PDA plugs (5 branches per fungal isolate). Five branches were inoculated with sterile PDA plugs as a negative control. The inoculations were performed three times. All treatments were wrapped with fresh film for 3 days. Dark brown necrotic lesions were observed on all inoculated branches 22 days post-inoculation. The controls had no symptoms. The pathogen was reisolated from all the inoculated branches, fulfilling Koch's postulates. To our knowledge, this is the first report of F. solani causing twig canker on English walnut in Xinjiang, China. Twig canker disease often cause a large number of branches to dry out and die. If the disease control and prevention is neglected, the productivity of the English walnut will be seriously affected in the cultivation area. Our finding will provide valuable information for prevention and management of twig canker on English walnut.

The Lateral Growth of Branches into Small Canopy Gaps: Implications for Competition between Canopy Trees

Much research in forest ecology has been devoted to examining the effect of gap formation on regeneration dynamics. However, comparatively little research has examined the process of gap closure, in which larger trees bordering the gap grow laterally to exploit available light. Thus, it remains uncertain whether disturbance disrupts or reinforces the competitive hierarchy established among different species and sizes classes. We quantified the lateral growth of three hardwood tree species with differing autecologies both before and after the formation of small gaps created by single-tree selection. Linear mixed-effect models were employed to link lateral growth to species and stem diameter to examine whether gap formation favors intolerant species and small trees in the canopy. Additional models were also developed to examine the relationship of lateral growth with branch length and tree height. Before gap formation, the mid-tolerant yellow birch grew considerably faster than the tolerant sugar maple and American beech. However, yellow birch was less responsive to gap formation (~16%) than sugar maple or beech, whose lateral growth increased by 42% and 39%, respectively. This suggests that gap formation reinforces the competitive dominance of tolerant species. In contrast, gap formation disrupts the competitive dominance of large trees in the canopy, since the lateral growth of small trees increased five times that of large trees. Thus, small silvicultural gaps bordered by small trees may close too quickly to permit the regeneration of mid-tolerant species. Following the release, small trees also grew faster than their larger counterparts, suggesting that lateral growth declines as the cost of reproduction increases with tree size. However, lateral growth did not vary with tree height or branch length, suggesting that lateral growth does not decline due to increasing support costs or hydraulic limitation.

Diversity of acarine fauna (Acari: Parasitiformes, Acariformes) inhabiting ornamental trees and shrubs in Hungary: A review

AbstractThis paper reviews of the recent progress in the acarological researches and knowledge on mites occurring in the canopy of ornamental trees and shrubs. The inventory of Acari includes 444 mite species belonging to 33 families which were recorded from 283 hardwood tree and shrub species of 45 plant families. The highest number of mite families and species were reported from the families Rosaceae (21 mite families), Salicaceae (20) and Oleaceae (17), and Salicaceae (99 mite species), Rosaceae (98) and Fagaceae (63), respectively. The most diverse acarine fauna was found on Acer campestre (37 mite species), Prunus spinosa (37), Acer pseudoplatanus (33), Tilia cordata (33) and Salix alba (31). The most frequently occurring mite species were Euseius finlandicus (on 78 host species), Tydeus californicus (64) and Zetzellia mali (60).

Effects of root litter traits on soil organic matter dynamics depend on decay stage and root branching order

Decaying roots contribute disproportionately to soil organic carbon (SOC) stocks in many ecosystems, yet few studies have examined the afterlife effects of root trait variability on the formation, stability and mineralization of SOC. In order to assess how root functional class (absorptive vs. transport) and mycorrhizal association (ectomycorrhizal vs. arbuscular mycorrhizal fungi) affect both formation and loss of SOC, we decayed lower-order absorptive (orders 1–2) and higher-order transport (orders 3–4) roots from six arbuscular mycorrhizal (AM) and six ectomycorrhizal (EcM) associated hardwood tree species in an isotopically distinct soil under laboratory conditions. We found that root litter effects on SOC differed significantly among root functional classes and mycorrhizal types. AM absorptive and transport roots (high in nitrogen and soluble compounds) contributed more to the formation of new mineral-associated organic carbon (MAOC), but also contributed to higher mineralization of native SOC (via priming effects). Moreover, absorptive AM roots formed MAOC gradually and rates saturated, whereas ECM roots formed MAOC more quickly, despite slower decay (via greater formation efficiency). Together, these findings demonstrate how different combinations of root traits might contribute to soil C balance, and that failure to account for the chemical and morphological heterogeneity of roots, as well their interactions with microbes over time, may lead to incorrect projections of SOC stocks and turnover.

Compressive Properties of Cross-Laminated Timber Panels Made of Hardwood Tree Species from the Appalachian Region

Cross-laminated timber (CLT) panels are an innovative wooden product that has gained popularity in recent years because it has a high strength-to-weight ratio, improves construction efficiency, and it is a natural and renewable material. Therefore, the recently released 2021 International Building Code (IBC) include guidelines for CLT panels for the construction of buildings of up to 18 stories. The construction applications of CLT panels as well as the research initiatives have largely centered on softwood tree species such as laminates, and the application of hardwood species has yet to be investigated. This paper documents the structural behavior of several hardwood species abundant in the Appalachian region and demonstrates the promising feasibility of using these species in the construction industry with CLT panels considering the architectural and structural behavior and economic aspects. The hardwood tree species selected are abundant in the Appalachian region and this paper highlights their potential as a construction material and provides an insight for future development. Three hardwood species including red maple, sweetgum, and sycamore are considered for this study, and three- and five-ply panels are fabricated to evaluate their behavior. The samples are tested in three directions for compression to understand the orthotropic behavior. Considering the softwood species including southern yellow pine and Douglas fir as a baseline for comparison, a total of 120 samples are tested and evaluated based on ASTM standards. The results show an average higher compressive strength from sweetgum panels followed by red maple, sycamore, Douglas fir, and southern yellow pine in the main directions used for structural walls. The findings imply a potential market for the underutilized hardwood species in Appalachia, which may lead to future economic development in the region.

Competitive interactions under current climate allow temperate tree species to grow and survive in boreal mixedwood forest

With climate change, climatic optima are shifting poleward more rapidly than tree migration processes, resulting in a mismatch between species distributions and bioclimatic envelopes. Temperate hardwood tree species may take advantage of the release of climate constraints and forest management to migrate into the boreal forest. Here, we use the SORTIE‐ND forest simulation model to determine the potential for the persistence of three temperate species (sugar maple, red maple and yellow birch) when introduced at seedling stage in typical balsam fir–paper birch (BF–PB) bioclimatic domain stands of eastern Canada, quantifying the consequences on the native species composition. SORTIE‐ND is a spatially explicit, individual‐based forest stand model that simulates tree growth, regeneration and mortality. We performed a novel parameterization of the SORTIE‐ND tree growth equation allowing for the inclusion of climate modifiers on tree growth. After validating our model with data from permanent forest inventory plots, we modeled the dynamics of unharvested stands at different successional stages, as well as post‐harvest stands, after the addition of sugar maple, red maple and yellow birch seedlings at different densities. Our results show that current BF–PB domain climate conditions do not limit growth and survival of temperate species in boreal stands. Of the temperate species introduced, sugar maple had the lowest ability to grow and survive by the end of the simulation. Species assemblages of host stands were impacted by the presence of temperate species when the addition of seedlings was above 5000 temperate seedlings per hectare at the beginning of the simulation. For stands that were recently clear cut, temperate seedlings were unable to grow due to intense competition from aspen regeneration. Our results suggest that both current climate and competitive interactions between temperate species and boreal species should not impede the ability of temperate species to grow and survive in the BF–PB domain.

Xerophytic hardwood retention promotes competition over facilitation in longleaf pine woodlands in the absence of fire

Recent reports of xerophytic hardwood facilitation of longleaf pine seedlings challenge the traditional paradigm that co-occurring hardwood tree species constrain longleaf pine (Pinus palustris Mill.) regeneration. To better understand this dynamic, we established an experiment examining the effects of hardwood retention duration (no retention, one-year retention, four-year retention), overstory basal area (2-to-41 m2 ha−1), and understory vegetation cover on microclimatic conditions and longleaf pine seedling survival, development, physiological performance, and brownspot needle blight (Mycosphaerella dearnessii) infection in the Sandhills Ecoregion of North Carolina, USA. Light availability (μmol m−2 s−1) at the forest floor (∼20 cm) was reduced by 27% in the four-year retention treatment which significantly exceeded reductions found in the one-year (<1%) and no retention (<1%) treatments, respectively, post midstory removal. However, midstory treatment had little effect on soil moisture and temperature at 15 and 30 cm depth. Longleaf pine seedling survival (85%), aboveground biomass (7.51 g dry weight), and root collar size (1.53 cm) were significantly highest in the no retention treatment compared to the four-year retention treatment. Between treatments with midstory retention (one-year vs. four-year retention), longleaf pine seedlings were statistically larger in the one-year retention treatment (5.37 g dry weight) compared to the four-year retention treatment (4.84 g dry weight). Seedling brownspot infection did not statistically vary among midstory retention treatments. Across all midstory treatments, overstory basal area had a stronger negative effect on longleaf pine seedling aboveground biomass development, root collar development and brownspot infection compared to midstory hardwood stem density or understory vegetation cover. Moreover, for most measured metrics, overstory basal area had a stronger negative effect on longleaf pine physiological performance compared to midstory hardwood stem density. Collectively, these results indicate that hardwood retention did not facilitate longleaf pine survival and development in the grass stage and that asymmetric competition from the overstory represents a stronger impediment to longleaf pine sapling recruitment than midstory hardwoods.

First report of Macrophomina phaseolina causing leaf blight on Pometia pinnata in Malaysia.

Pometia pinnata (family Sapindaceae), locally known as 'Kasai', is a tropical hardwood and fruit tree species grown in Malaysia. The decoction of the bark is used for the treatment of fever, sores and colds, while the fruits are edible (Adema et al. 1996). In May 2021, irregular brown spots and necrotic lesions were observed on 'Kasai' with an incidence and severity of approximately 60% and 10% on 10 plants in a nursery (5°55'30.7"N 116°04'36.2"E) in Penampang, Sabah province. When the disease progressed, the spots coalesced into extended patches, blightening the leaves and, gradually, the entire foliage. Small pieces (5 x 5 mm) of infected leaves were excised from the infected margin, and then surface sterilized according to Khoo et al. (2022b), and plated on potato dextrose agar (PDA), and cultured at 25 °C. for 6 days. Colonies were dark brown in color initially whitish on the PDA. The color of fungal colony was dark as the culture aged. Semi-appressed mycelia were observed on the plates with abundant microsclerotia engrossed in the agar. Aggregation of hyphae formed black and round to oblong or irregular shaped microsclerotia. Thirty sclerotia from a representative isolate measured average 63-171 μM length x 57-128 μM wide. The morphological features matched the description of Macrophomina phaseolina (Abd Rahim et al. 2019). The fungal genomic DNA was extracted based on Khoo et al. (2022a and 2022b). PCR was performed using primer sets ITS1/ITS4 (White et al. 1990), EF1-728/EF2 (O'Donnell et al. 1998; Carbone and Kohn, 1999) and T1/T22 (O'Donnell and Cigelnik 1997) to amplify the internal transcribed spacer (ITS) region of rDNA, translation elongation factor 1-α (TEF-1α) region and partial β-tubulin (TUB) gene. PCR products with positive amplicons were sent to Apical Scientific Sdn. Bhd. in Malaysia for sequencing. According to results (GenBank Accession No. OK465197, OM677767, ON237461), they were 100% identical with the reference sequence of Macrophomina phaseolina containing approximately 537 bp, 438 bp and 659 bp of the presented ITS, TEF-1α and TUB region (GenBank Accession No. MN629245, MN136199 and KF952208, respectively). The pathogen was identified as M. phaseolina based on its morphological and molecular data (Abd Rahim et al. 2019). To confirm the pathogenicity test, three non-wounded and healthy leaves of one-month-old 'Kasai' seedlings were inoculated with mycelium plug (1 x 1 cm) of M. phaseolina. Additional three 'Kasai' seedlings were inoculated with sterile PDA agar plug (1 x 1 cm) to serve as controls. The seedlings were monitored and incubated in a greenhouse at ambient temperature based on Iftikhar et al. (2022). After 6 days of inoculation, all infected leaves exhibited the symptoms as observed in the nursery, while the controls remained asymptomatic. The experiment was repeated twice. Re-isolation was performed from the symptomatic leaves and controls. The reisolated fungal isolates were identical to M. phaseolina morphologically and molecularly. No pathogens were isolated from the mock controls. M. phaseolina has been reported to cause leaf blight on Jasminium multiflorum in India (Mahadevakumar and Janardhana, 2016), and Crinum asiaticum and Hymenocallis littoralis in Malaysia (Abd Rahim et al. 2019). To our knowledge, this is the first report of M. phaseolina causing leaf blight on 'Kasai' in Malaysia and worldwide. Our findings serve as a warning for the authorities and farmers that the disease threat has appeared for 'Kasai' in Malaysia.

Determination on Tree Species Selection for Lingzhi or Reishi Medicinal Mushroom Ganoderma lucidum (Agaricomycetes) Cultivation by Fourier Transform Infrared and Two-Dimensional Infrared Correlation Spectroscopy

As a wood-degrading Agaricomycetes mushroom, Ganoderma lucidum can be cultivated on broad-leaf hardwoods. Generally, producers care about the yield, but not the quality of G. lucidum cultivated by different tree species. In this study, five broad-leaf hardwood tree species-Quercus variabilis Bl. (Qv), Castanea mollissima Bl. (Cm), Liquidambar formosana Hance (Lf), Dalbergia hupeana Hance (Dh), and Platycarya strobilacea Sieb. et Zucc. (Ps)-were selected for cultivating of G. lucidum. The chemical compositions of G. lucidum fruiting bodies produced by these tree species were determined by Fourier transform infrared and two-dimensional infrared correlation spectroscopy in order to select the most suitable tree species for cultivation. The overall spectra showed less discrimination of each peak variation detected and properly kept most of the primary metabolites. The second derivative unfolded the stagnation of the first spectrum and more base peaks were detected especially in the range of the first two sections. The protein content contained in G. lucidum cultivated on Ps was 92%, like that on Dh. On the other hand, only 27% similarity was determined in G. lucidum cultivated on Ps and Qv. Therefore, the correlation of this range for the protein content can help in tree species selection. The active sequence of 2DIR spectral could be determined by the active bonding of the component reacted to the perturbation. The result could provide a scientific basis for the selection of tree species and the comprehensive utilization of broad-leaf tree resources on G. lucidum cultivation.

Impacts of short-term feeding by spotted lanternfly (Lycorma delicatula) on ecophysiology of young hardwood trees in a common garden.

Spotted lanternfly (SLF; Lycorma delicatula White; Hemiptera: Fulgoridae) invaded the US from Asia and was first detected in 2014; currently, populations have established in 14 states primarily in the Northeast and Mid-Atlantic. It feeds voraciously on phloem sap from a broad range of host plants, with a preference for tree of heaven (Ailanthus altissima [Sapindales: Simaroubaceae]), grapevines (Vitis spp. [Vitales: Vitaceae]), and several common hardwood tree species. We evaluated the impacts of fourth instars and adults confined to a single branch or whole trees on gas exchange attributes (carbon assimilation [photosynthetic rate], transpiration and stomatal conductance), selected nutrients, and diameter growth using young saplings of four host tree species planted in a common garden. In general, the effects of adults on trees were greater than nymphs, although there was variation depending on tree species, pest density, and time post-infestation. Nymphs on a single branch of red maple (Acer rubrum [Sapindales: Sapindaceae]), or silver maple (Acer saccharinum [Sapindales: Sapindaceae]) at three densities (0, 15, or 30) had no significant effects on gas exchange. In contrast, 40 adults confined to a single branch of red or silver maple rapidly suppressed gas exchange and reduced nitrogen concentration in leaves; soluble sugars in branch wood were reduced in the fall for silver maple and in the following spring for red maple. Fourth instars confined to whole silver maple trees reduced soluble sugars in leaves and branch wood, and reduced tree diameter growth by >50% during the next growing season. In contrast, fourth instars in whole tree enclosures had no effects on black walnut (Juglans nigra [Fagales: Juglandaceae]). SLF enclosed on tree of heaven at 80 adults per tree suppressed gas exchange after two weeks of feeding, but did not alter non-structural carbohydrates, nitrogen concentrations, or tree growth. Results suggest that moderate to heavy feeding by SLF on young maple saplings may impair tree growth, which could have implications for production nurseries and forest managers.

Habitat suitability model and range shift analysis for American Chestnut (Castanea dentata) in the United States

American chestnut (Castanea dentata) was a multifunctional hardwood tree species that provide both economic and ecological benefits in the United States. It was a major source of timber before the chestnut blight (Cryphonectria parasitica) invasion wiped out the stands of this species from the forest between the early 1900s and 1950s. Our study focuses on the estimation of suitable habitat in the eastern US, range shift predictions, and identification of habitat drivers for American chestnut (AMC) in the eastern US to help corroborate the restoration efforts of C. dentata using an ensemble model from five species distribution modeling (SDMs) methods while also projecting the prediction until 2100 in response to the changing climate. 1806 occurrence records were obtained from four sources including the United States Department of Agriculture (USDA) Forest Service. The result from the SDM techniques shows a model accuracy of the true skill statistics (TSS) and Area-Under-the-Curve (AUC) of greater than 0.8 and 0.90 respectively, which were ensembled. The historic suitable habitat of AMC compared to the present habitat suitability prediction in the US shows a significant reduction. The mean temperature of the warmest quarter, precipitation seasonality, and temperature seasonality are the top three variables dictating the distribution of the American chestnut in the US. The future projection also shows up to 100% less suitable habitats by the end of the century under high emissions and high precipitation with a northeast range shift up to 476.9 km. Modeling the American chestnut's habitat suitability is imperative for a successful restoration program and these results highlight the potential need for greater conservation and use of southern genotypes.