Radial Growth Research Articles (Page 1)

Tree species mixing has been widely recognized as an effective silvicultural strategy for enhancing both stand productivity and biodiversity. Nevertheless, its effects on branch radial growth and the underlying physiological mechanisms remain inadequately understood. In this study, we measured branch ring widths and 22 functional traits of pure and mixed plantations of Pinus massoniana and Castanopsis hystrix to investigate the effects of species mixing on branch radial growth, to assess potential variations between even- and uneven-aged forest mixtures, and to elucidate the underlying physiological mechanisms. Our results demonstrated that tree species mixing generally promoted branch radial growth, as indicated by the basal area increment for both studied species. The effect of species mixing on branch radial growth was not significantly different between even- and uneven-aged mixtures for C. hystrix; however, it diminished with increasing age of P. massoniana. Our findings indicated that the radial branch growth of P. massoniana was related to larger tracheid radial diameter and higher hydraulic conductance. In contrast, increased branch radial growth of C. hystrix was more related to higher specific leaf area and thinner leaves in mixed plantations, which potentially improved the light capture efficiency and leaf carbon turnover rate. Our results also indicated that tree species mixture is an effective strategy for enhancing branch growth. The positive mixing effect could diminish as P. massoniana reaches an over-mature age in the mixed-species stand, implying that species mixing practices during the early stages of stand development provide more benefit. The findings provide valuable insights for formulating reasonable forest management strategies and improving the understanding of the eco-physiology of species mixing effects on tree growth.

Abstract Background Wildfire size and severity have been increasing in the southwestern US since the mid-1980s as a direct result of anthropogenic climate change and land management practices. Large, high severity wildfire, including reburns, combined with two decades of drought, may result in ecosystem reorganization, as some areas dominated by conifer forest are no longer able to recover, and are replaced or outcompeted by oaks or shrubs. We apply a unifying resilience framework distinguishing post-fire processes of persistence, recovery, and reorganization of mixed conifer and pine-oak forests in two southern Arizona Sky Island mountain ranges. The Santa Catalina and Rincon Mountains experienced multiple wildfires in the early 2000s, followed by a large reburn in the Santa Catalina Mountains in 2020. We evaluated conifer radial tree growth as a measure of individual tree persistence, seedling recruitment as a measure of conifer and oak population recovery, and differences in species importance values in burned and unburned areas, to detect potential ecosystem reorganization, including changes in dominant plant trait groups. Results In our tree growth analysis, we found resilience to both drought and wildfire in three dominant conifer species. Ponderosa pines ( Pinus ponderosa ) and southwestern white pines ( Pinus strobiformis ) that survived both high and low severity fire showed non-significant positive growth trajectories following wildfire exposure in 2003. Douglas-fir ( Pseudotsuga menziesii ) growth was more climate-dependent and adversely affected by fire exposure. In areas that burned only once, post-fire conifer recruitment was found in the majority of burned plots that were sampled 18–19 years after fire, although density varied greatly. We found evidence of incipient community reorganization reflecting plant traits (e.g., resprouting species) especially in mixed-conifer communities. Composition analysis indicated some loss of conifer overstory dominance in areas burned at high severity in higher elevations; in general, these were replaced mainly by aspen ( Populus tremuloides ). Conclusions The study landscapes showed evidence of all three post-fire processes of persistence, recovery, and reorganization in the 18–19 years after the initial fire events. The complex mosaic of fire severity and topography promoted landscape-scale recovery, while some high severity areas show evidence of incipient or transient reorganization. Early (1 year) post-fire vegetation responses following the 2020 reburn were highly variable and dependent on sequences of fire severity and plant traits; these constitute initial conditions for future trajectories of change in southwestern forests under the influence of changing climate and fire regimes.

Abstract Herbivory may offset climate change-driven treeline expansion into the tundra, but the strength of this effect is rarely quantified. This study leverages a unique semi-natural experiment involving Malla Strict Nature Reserve in northernmost Finland, where the reindeer herding regime shifted from being nearly ungrazed for several decades to being heavily grazed for the past two decades. This is contrasted by low grazing pressure in the adjacent herding district in Norway, which is separated by the border fence preventing free reindeer movement between the two countries. We aimed to quantify the effects of reindeer browsing and grazing on mountain birch treeline position and structure on both sides. We measured seedling numbers and the allometry of trees, vegetation composition, nutrient concentrations in soils and birch leaves, and radial tree growth. We found higher numbers of seedlings and saplings in the area with lower reindeer density, indicating that the treeline may be responding to climatic forcing by expanding into the tundra. Contrastingly, we observed almost no recruitment and treeline expansion in the area with high reindeer density. Furthermore, while birch leaves showed signs of nitrogen enrichment under high reindeer density, we found no differences in soil chemical composition or birch tree growth rates. Our results suggest that the high density of reindeer in Malla Strict Nature Reserve keeps the treeline in a browsing trap, thereby preventing climate change-driven forest expansion. These results are highly relevant for land management decisions that aim to preserve mountain tundra.

Crown rot, caused by various fungal pathogens, is a major post-harvest disease of bananas, leading to significant storage losses. Biocontrol by antagonistic microorganisms is a promising alternative to synthetic fungicide application. Trichoderma spp. are well-known biological control agents due to their strong antagonistic properties. Soil samples were collected from banana-cultivated orchards in the districts of Mayurbhanj, Jagatsinghpur, Jajpur and Ganjam. A total of 4 Trichoderma species were isolated using the serial dilution method: T. asperellum (8 isolates), T. atroviride (4 isolates), T. harzianum (5 isolates) and T. hamatum (6 isolates). Based on their micro-morphological and cultural characteristics, bioagents were identified. Trichoderma isolates were selected for in vitro testing against the Fusarium species by conidia germination assay and dual culture assay. Among the tested isolates, T. asperellum showed the highest inhibition of conidial germination (88.24 %) and mycelial radial growth (91.22 %) of F. equiseti. T. atroviride showed the lowest level of inhibition of conidia germination and mycelial radial growth against the F. equiseti. Solid-phase microextraction (SPME) was applied to trap volatiles emitted by T. asperellum. The GC/MS profiling revealed the presence of antifungal compounds, including azetidine, 1-Methylideneindene, phenylethyl alcohol and fluoro(trinitro)methane, which are involved in antifungal activity and the dominant compound was tentatively identified as phenylethyl alcohol (PEA), making up 21.79 % of the peak area with 96.24 % match in 7.15 retention time. This study indicates that T. asperellum is an effective antagonistic biocontrol agent and can produce volatile antifungal compounds that involve major mechanisms against Fusarium spp. in vitro conditions.

Introduction: Hemodynamics and wall biomechanics jointly drive ascending-aortic remodeling in bicuspid aortic valve (BAV) disease, yet most in silico studies model only flow or strain. Manual segmentations yield noisy meshes, impeding strain and computational fluid dynamics (CFD) analyses. We present an end-to-end framework integrating patient-specific CFD and dynamic strain mapping via our Bayesian remeshing algorithm, preserving geometry and eliminating manual mesh edits. Objective: Develop and validate an end-to-end approach to automate mesh generation, quantify surface strain, and enable strain mapping and patient-specific CFD in ascending aortas of normal and bicuspid aortic valves. Methods: We retrospectively analyzed 12 ECG-gated 4D CT datasets from 11 adults in a BAV study. Two observers performed semi-automated segmentation in ITK-SNAP using manual annotation, random forest voxel classification, and contour evolution; interobserver agreement—Dice coefficient, mean surface distance (MSD)—is reported as median [IQR]. Segmentations were converted to surface meshes and remeshed via a Bayesian adaptive algorithm. A reference mesh was propagated across cardiac phases using deformable registration; registration accuracy was assessed by MSD against meshes from manual segmentations. Areal strain was computed as fractional area change from end-diastole (Figure 1). Transient-dynamic CFD was performed on three patients to simulate flow and wall shear stress (WSS); aortic growth, reported in Figure 2, was derived from follow-up CT-based maximum diameters. Results: Table 1 summarizes patient characteristics. Manual segmentations showed strong interobserver agreement (Dice 0.96 [0.95–0.99]; MSD 0.45 mm [0.17–0.70]). Propagated meshes had a median MSD of 0.42 mm [IQR 0.34–0.74] (n = 24) against manual references. Peak areal strain ranged 7–23%, and WSS 2–6 Pa. Figure 2 shows strain and WSS maps for two representative BAV cases. In these cases, lower peak WSS/velocity coincided with faster radial growth over subsequent scans, mirroring inverse WSS-growth trends seen in larger BAV cohorts. Conclusions: Our 4D CT workflow produces spatially aligned WSS and areal-strain maps, without manual mesh edits. Preliminary results suggest higher peak WSS may be negatively associated with aortic growth rate, consistent with prior studies. This proof-of-concept demonstrates technical feasibility and motivates further study of WSS-strain interaction as a predictor of BAV aortic remodeling.

Climate change is advancing leaf emergence in the spring and delaying leaf senescence in the fall. This extended leafing period may increase tree radial growth, with large potential impacts on wood supply and carbon sequestration, but empirical evidence supporting this remains limited. To address this, we have established the Acadian Phenocam Network (APN), a state-of-the-art monitoring system spanning 24 sites and 12 tree species in the Acadian forest in Nova Scotia, Canada. The APN integrates high-frequency observations of leaf phenology, radial growth, local meteorology and soil dynamics at each site. The APN will enable researchers to 1) quantify the response of leaf phenology and radial growth to seasonal weather regimes for a variety of tree species, 2) explore connections between leaf phenology and radial growth across a range of site and stand conditions, and 3) develop and enhance models to anticipate climate change impacts on phenology and growth. Further, the APN is designed to serve as a long-term observational system for continuously tracking climate impacts. Insights stemming from this network will support climate-focused forest management practices through characterizing the adaptive capacity of tree species and improved projections of forest growth and development.

Deciphering roles of Rad25, Rad3A, Rad3B and Ssl1 in UV damage recovery and insect-pathogenic lifecycle of Beauveria bassiana.

Background/Objective. Sudden death syndrome caused by Fusarium virguliforme (Fv) and White mold caused by Sclerotinia sclerotiorum (Ss) are the most important soybean disease in regards to yield loss in the Northern USA. Few studies have estimated for Fv and Ss isolates from Iowa, the EC50 mycelial growth of the fungicide pydiflumetofen for Fv and Ss; likewise, the EC50 sclerotial production for Ss. Experimental development. Potato dextrose agar (PDA) at 1/3 strength was amended with Saltro(pydiflumetofen 41.7%) at 0.0008, 0.0042, 0.0083, 0.0417, 0.0834, 0.8340, and 834 ppm from serial dilutions. Isolates were incubated in darkness at 25 °C. Fv isolates were evaluated at 7 days and Ss isolates at 48 h after inoculation, measuring the radial growth. The sclerotia number and dried-weight were measured after 21 days of incubation. Results. Pydiflumetofen absolute EC50 values for mycelial growth Fv were 0.045 and 0.048 ppm. The Fv contemporary isolate (FV-RD-0024; collected in year 2024), and the historical isolate (NE205; collected in year 2006—years before pydiflumetofen introduction in the market), both presented EC50 mycelial growth in the range of the baseline (0.04–0.24 ppm) in the USA. EC50 values for the mycelial growth of Ss contemporary isolates ranged from 0.011 to 0.046 ppm, which fall in the baseline from soybean and non-soybean hosts from China. Concentrations of 0.834 and 834 ppm were statistically different (no sclerotia production) than the control, which showed 14.6 sclerotia and 0.066 g. Conclusion. The EC50 mycelial growth of F. virguliforme Iowa isolates fall in the range of previous reported for the USA. The EC50 mycelial growth of S. sclerotiorum Iowa isolates fall in the range previous reported outside the USA. Pydiflumetofen has the potential to diminish the sclerotial production but more studies are needed.

Abstract As global warming drives plant upward migration, the alpine tundra of Changbai Mountain is experiencing encroachment by Deyeuxia angustifolia (Komarov) Y. L. Chang, a low-elevation herb. However, its impact on native shrubs such as Rhododendron aureum Georgi remains unclear. Here, we analyzed the radial growth trends and climate sensitivity of R. aureum across elevations and encroachment gradients using linear and mixed-effects model methods, and explored the mediating roles of soil properties and plant traits. Our study revealed that R. aureum exhibited stronger positive long-term growth trend at higher elevations compared to lower elevations. Mild and moderate encroachment of D. angustifolia enhanced the positive growth trend of R. aureum, especially at the low elevations. Moreover, R. aureum showed weak climate sensitivity at mid-elevation but stronger responses to winter temperatures at low elevation and to spring–summer temperatures and precipitation at high elevation. D. angustifolia encroachment further intensified this sensitivity, characterized by stronger negative responses to spring, autumn, and winter temperatures but positive responses to summer temperatures and autumn precipitation. Overall, elevation primarily influenced R. aureum growth and its sensitivity to precipitation through soil conditions and plant size traits. Soil conditions and leaf economic traits influence temperature sensitivity. These findings advance understanding of alpine vegetation dynamics and contribute to ecosystem conservation under climate change.

In northeastern North America, episodic eastern spruce budworm (Choristoneura fumiferana) outbreaks extensively defoliate balsam fir (Abies balsamea) and spruces (Picea glauca, P. rubens, P. mariana). We investigated eastern spruce budworm defoliation in eastern hemlock (Tsuga canadensis), a reported alternate host species, during previously documented outbreaks in Maine, USA. We compiled red spruce and hemlock tree-ring series from nine sites, seven of which showed synchronous radial growth reductions in spruce and hemlock during documented budworm outbreaks. Outbreak evidence varied among sites, but growth reductions were observed in six study sites during a 1914 outbreak. Synchronous growth reductions between spruce and hemlock suggest that when budworm defoliation occurred in spruce at a given site, hemlock typically experienced at least some level of defoliation. Relative budbreak synchrony with preferred host species may contribute to hemlock’s suitability as a host. This research is timely given the recent spruce budworm population increase in the region.

The radial growth of temperate forests responds to climate change with remarkable variation across space and between species. However, there is limited understanding of how growing season extension and increasing drought stress contribute to long-term growth trends. Here, we calibrate the VS-Lite growth model using 2013 tree-ring chronologies from ten broadleaved and five coniferous genera in Central-Southeast Europe to predict intra-annual wood formation under four SSP climate scenarios through the 21st century. Results show that forecasted summer drought stress will be temporarily offset by an extended growing season, leading to stable or positive trends in tree-ring widths until a tipping point in the 2040s–2050s. During the second half of the 21st century, high-emission scenarios lead to growth acceleration in humid coniferous forests due to growing season extension and enhanced growth rate. In contrast, forecasted extension of the growing season is insufficient to compensate for declining summer growth rates at drier sites, resulting in significant growth reduction for all genera, particularly during dry years. Our results demonstrate that adjusting intra-annual wood formation to seasonal moisture availability may become crucial for tree survival in warmer climates. Furthermore, we highlight that only low-emission scenarios support non-declining stem growth in dry forests with current species composition.

The morphology, polymorphism transformation, and influencing factors on self-assembly growth of acid-heat-treatment-induced glutenin amyloid fibers (GAFs) were investigated by multiple techniques. The results showed that GAFs were hollow microtubes with thread-like structures on the surface formed by twisting of filaments composed of low-molecular-weight glutenin aggregates (35, 41, and 57 kDa), conforming to the monomer model. β2-type antiparallel sheet plays a critical role in forming GAF cross-β structures. Moderate glutenin concentrations (3-7%) facilitated fibril longitudinal and radial growth, whereas the massive instantaneous nucleation at higher concentrations inhibited further growth. Low pH significantly enhanced energy change dominated by electrostatic repulsion, reducing the twisting angle, and increasing the fiber length and pitch. Salt ions with concentration examined induced protein aggregation through electrostatic shielding, delaying the self-assembly process and hindering the longitudinal growth of fibers. The polymorphism transformation of the fibers from microtubes to ribbons and their moduli can be controlled by solvent polarity.

Gnomoniopsis smithogilvyi is the causal agent of brown rot, one of the main diseases of chestnuts that is threatening the sustainability of the global market. Michigan is the leading producer of commercial chestnuts in the United States. After the first isolation of G. smithogilvyi in 2016, chestnut brown rot was identified in 80% of Michigan orchards. The pathogen infects the flowers in the field, with symptoms affecting nut quality at harvest time and during storage. For this reason, fungicide treatments are crucial to prevent infection in the flowers and later in the kernels. This study aims to compare the in vitro efficacy of fifteen different chemical and biologically based fungicides against G. smithogilvyi. The fungicide potential of each product was evaluated for mycelial radial growth and conidial germination by calculating the EC50. FRAC (Fungicide Resistance Action Committee) group 3 fungicides showed the best fungicide activity for both mycelial growth and conidial germination. However, biologically-based fungicides containing Bacillus spp. had no significant differences from FRAC 3, 7, and 11 fungicides. Phosphonates had a statistically lower fungicide activity on conidial germination compared to FRAC 3, 7, 11 and BM02, but same activity against mycelial radial growth. Further investigations should be done to evaluate the potential efficacy of these products in the orchard, considering that there is not always a correlation between in vitro and in planta activity. Our findings will help chestnut growers select chemical and biologically-based fungicides to complement their field practices for chestnut brown rot control, encouraging the rotation between different active ingredients.

Sclerotium rolfsii is a significant soil borne phytopathogenic fungus that leads to considerable yield losses in economically important crops. This study assessed the impact of temperature and culture media on the mycelial growth, sclerotial production, and germination of S. rolfsii. In this present study six different cultural solid media viz. V-8 juice agar, Czapek Dox agar, Potato dextrose agar, Oat meal agar, Cluster bean stem extract agar and water agar were analyzed for in vitro mycelium growth were observed the best radial growth found in Oat meal agar (88.29 mm) followed by Potato dextrose agar media (85.28 mm), Czapek agar (72.24 mm), Cluster bean stem extract agar (70.23 mm) and V-8 juice agar (68.23 mm). Maximum diameter (89.40 mm) and sclerotia count (571.00 per plate) were recorded on Potato dextrose agar (Hi-media) at 30 0C and 20 days after inoculation respectively, followed by 32ºC (77.74 mm) and sclerotia count (471.00 per plate).

Anthracnose caused by Colletotrichum truncatum is a major constraint in soybean production, affecting leaves, stems, pods, and seeds. In the present study, ten isolates of C. truncatum were collected from ten locations across nine districts and seven agro-climatic zones of Madhya Pradesh. Their cultural and morphological characteristics were evaluated on five different media: Potato Dextrose Agar (PDA), Oatmeal Agar (OMA), Corn Meal Agar (CMA), Czapek’s Dox Agar (CDA) and Richard’s Agar (RA). Colony morphology, mycelial density, sporulation, and radial growth were recorded at 2nd, 5th, 8th, and 11th days post-inoculation. Significant variability was observed among isolates and media in terms of colony texture, colour, mycelial density, and sporulation. PDA supported the fastest early growth and maximum final radial expansion, while OMA and CDA promoted vigorous sporulation. Corn Meal Agar also supported good growth and sporulation for most isolates. Richard’s Agar consistently exhibited the lowest radial growth and sparse sporulation. These findings indicate that PDA, OMA, and CMA are the most suitable media for studying growth and reproductive potential of C. truncatum, and the observed isolate-specific differences highlight considerable intraspecific variability, which may have implications for disease management and inoculum production.

Abstract Background Blue mold rot of onion is one of the most damaging diseases, reported in Pakistan during the current studies, and is responsible for losses at a considerable level in onion growing areas, during transportation, and in storages. The aim of the present study is to evaluate the antifungal potential of four Trichoderma species against Penicillium expansum; the causal agent of blue mold rot of onion in Pakistan. Results Efficacy of in vitro findings exhibited that T. harzianum and T. viride inhibited the growth of the test fungus by about 63%, whereas T. virion, followed by T. hamentum, inhibited the radial mycelial colony growth of P. expansum by 46%, followed by 33%; moreover, control Petri plates showed the maximum radial mycelial colony growth of test fungus. Efficacy of in vivo study exhibited that T. harzianum was found most potential antagonist with the highest antagonistic impact on onion against blue mold rot severity %, followed by T. viride. The antifungal potential against disease and blue mold rot of onion disease caused by P. expansum was efficient and the rot severity % on onion was recorded 37.3% followed by 51.0% treated with T. viride followed by T. harzianum, respectively, whereas control group showed 86.7% rottening in the onions. Conclusion Based on the findings of the present study, the Trichoderma species showed antifungal potential to reduce the mycelial growth of P. expansum in vitro condition and against the blue mold rot severity % on onion. T. harzianum reduced rot severity by 64% and T. viride by 41% indicating promising potential to control the blue mold rot of onion and are recommended for application as postharvest biocontrol agents in Pakistan for management of blue mold rot of onion. Future studies should focus on formulation development and commercial-scale validation.

The present study was undertaken to assess the influence of different culture media on the mycelial growth and cultural characteristics of Sclerotium rolfsii, an important soil-borne pathogen responsible for collar rot in several crops. Eight culture media, namely Potato Dextrose Agar (PDA), Sabouraud Maltose Agar, Oat Meal Agar, Coon’s Agar, Corn Meal Agar, Ashby’s Mannitol Agar, Czapek’s Dox Agar, and Richard’s Agar were evaluated under in vitro conditions. Significant variation in radial growth, colony morphology and pigmentation were recorded among the tested media. Maximum mycelial growth was observed on Potato Dextrose Agar (90.00 mm), which was statistically at par with Sabouraud Maltose Agar (89.68 mm) and Oat Meal Agar (89.65 mm). Minimum growth was recorded on Czapek’s Dox Agar (67.86 mm). The colony characters ranged from cottony, fluffy, irregular to compact mycelium, while pigmentation varied from pure white to creamy and yellowish white depending on the medium. These results clearly indicate that PDA, Sabouraud Maltose Agar and Oat Meal Agar are the most suitable media for luxuriant growth and sporulation of S. rolfsii, and can be recommended for cultural variability studies, pathogenicity assays and further research on this pathogen.

Oil palm (Elaeis guineensis) yields 4–6 t oil/ha/year, but basal stem rot (BSR), mainly due to Ganoderma spp., can reduce yield by up to 69% (Vijay et al., 2016). No prior Indian reports exist beyond G. lucidum and G. applanatum (Mandal et al., 2003). In Aug 2023, 18% BSR incidence was recorded in 10-year-old Dura palms at ICAR-IIOPR, Andhra Pradesh, showing leaf drooping, necrosis, basal basidiocarps, and internal rot. The basidiome was perennial, sessile, non-laccate, woody, applanate, flabelliform (18 × 12 × 3.5 cm), with a hard, concentrically sulcate upper surface and tuberculate bumps, greyish to yellowish brown. Hymenophore was white to yellowish white, pores round to sub-circular, turning brownish yellow. Basidiospores (n=20) were brownish-orange, double-walled, ellipsoidal (7.6–9.9 × 5.3–7.1 μm), with hyaline myxosporium and finely echinulate eusporium. Pileipellis was yellowish to brownish yellow, with dextrinoid, acanthus-like branched apical cells. Hyphal system was trimitic (n=20): thin-walled generative hyphae (5.2 μm), thick-walled skeletal hyphae (5.8 μm), and greyish-orange binding hyphae (2.3 μm). Five isolates were obtained on Ganoderma selective medium (Ariffin and Idris, 1991) from 10 samples. Cultures produced dense white mycelium with filamentous margins and concentric rings, reaching 4.5 cm radial growth on PDA and 0.87 g dry biomass in PDB within 10 days at 25 ± 2 °C. DNA extracted using HiPurA fungal kit was prescreened with GB4 primers (Hilmi et al., 2022). The internal transcribed spacer (ITS, primers ITS4/ITS5), partial sequences of the translation elongation factor 1-alpha (tef1-α, primers 983F/1567R) and RNA polymerase II second largest subunit (rpb2; primers 5F/7CR) regions were PCR-amplified, with their sequences deposited in GenBank (PP159047, PQ530059, PQ583322), and BLAST searches showed 99–100% identity to JFL 14080966 (ITS, MH106867), MFLU 19-2221 (tef1-α, MN423157), and Dai 20544 (rpb2, MZ245400). Maximum likelihood analysis with 1,000 bootstrap replicates using MEGA X (Kumar et al., 2018) grouped isolates within the G. ellipsoideum clade. A representative culture was deposited in ITCC (Accession No. ITCC9346). Pathogenicity was confirmed by inoculating 4-month-old seedlings (ICAR IIOPR accession IOPPVDD000001) via root immersion in 100 mL of 10⁵ mycelial fragments/mL (T1) and T1 plus 20 mL soil inoculation (T2). Controls included sterile water, PDB, and untreated seedlings (n=10 per treatment). Inoculated seedlings showed stunting, chlorosis, necrosis, mycelial mats, and basidiocarps after 15 days; controls remained asymptomatic. Re-isolated fungus matched original identity, completing Koch’s postulates. This first report of G. ellipsoideum causing BSR in Indian oil palm signals emergence of a more aggressive pathogen. Its presence threatens long-term productivity and highlights the need for improved surveillance, resistant cultivars, and region-specific management strategies.

Abstract The combined contribution of CO2 fertilization and climate variability to arid and semi‐arid forest growth remains unclear. To disentangle these multiple influences, we used a preexisting process‐based ecophysiological model (MAIDENiso) to simulate tree growth changes during 1956–2010 in arid and semi‐arid regions of China. Results revealed that simulated tree growth was more dependent on climate trends than on atmospheric CO2 concentration. Mechanistic analysis showed that the regulation of stomatal conductance under water stress positively affected tree growth in the arid region, but had an opposite pattern in the semi‐arid region. Intrinsic water‐use efficiency (iWUE, measured from tree‐ring δ13C) has increased by 29% and 44% since 1900 CE in the arid and semi‐arid regions, respectively, but did not stimulate radial tree growth. This suggests that there will possibly be a continued increase (decrease) of radial forest growth in arid (semi‐arid) areas of northern China if the current climate trends remain in the next decades.

This study was focused on addressing the performance degradation in core microstructures of ultra-heavy steel plates (thickness ≥ 50 mm) caused by non-uniform cooling during thermo-mechanical controlled processing. Using microalloyed DH36 steel as the research subject, we systematically investigated the effects of cooling rate on the nucleation and growth of acicular ferrite and its consequent microstructure-property relationships through an integrated approach combining in situ observation via high-temperature laser scanning confocal microscopy with multiscale characterization techniques. Results demonstrate that the cooling rate significantly affects acicular ferrite formation, with the range of 3–7 °C/s being most conducive to acicular ferrite formation. At 5 °C/s, the acicular ferrite volume fraction reached a maximum of 74% with an optimal aspect ratio (5.97). Characterization confirmed that TiOx-Al2O3·SiO2-MnO-MnS complex inclusions act as effective nucleation sites for acicular ferrite, where the MnS outer layer plays a key role in reducing interfacial energy and promoting acicular ferrite radial growth. Furthermore, the interlocking acicular ferrite structure was shown to enhance microhardness by 14% (HV0.1 = 212.5) compared to conventional ferrite through grain refinement strengthening and dislocation strengthening (with a dislocation density of 2 × 108 dislocations/mm2). These results provide crucial theoretical insights and a practical processing window for strengthening-toughening control of heavy plate core microstructures, offering a viable pathway for improving the comprehensive performance of ultra-heavy plates.