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15 pages, 1363 KB  
Article
Tackling Conifer Needle Cast and Ash Dieback with Host-Derived Microbial Antagonists Exhibiting Plant Growth-Promoting Traits
by Milana Šilanskienė, Dorotėja Vaitiekūnaitė and Vaida Sirgedaitė-Polikaitienė
Microorganisms 2025, 13(11), 2517; https://doi.org/10.3390/microorganisms13112517 - 31 Oct 2025
Viewed by 269
Abstract
Needle cast (Lophodermium seditiosum Minter, Staley & Millar) in Scots pine (Pinus sylvestris L.) and European ash (Fraxinus excelsior L.) dieback (Hymenoscyphus fraxineus (T. Kowalski) Baral, Queloz & Hosoya) are among the most destructive forest and tree plantation diseases [...] Read more.
Needle cast (Lophodermium seditiosum Minter, Staley & Millar) in Scots pine (Pinus sylvestris L.) and European ash (Fraxinus excelsior L.) dieback (Hymenoscyphus fraxineus (T. Kowalski) Baral, Queloz & Hosoya) are among the most destructive forest and tree plantation diseases in Europe, threatening not only targeted plant species but also the whole ecosystem. While considerable research effort has focused on microbial antagonists against ash dieback, comparable investigations into needle cast biocontrol remain virtually absent from the literature. Here, isolated microbial antagonists from European ash and Scots pine were evaluated for their efficacy against respective pathogens. In vitro dual-culture assays revealed bacteria with strong inhibitory effects on pathogen growth, as well as multiple plant growth-promoting traits (PGPTs). It was found that bacteria from the genera of Pantoea, Erwinia, Priestia, and Pseudomonas inhibited the growth of H. fraxineus by ≥70%. Most significantly, our investigation revealed that bacteria isolated from Scots pine, belonging to the genera Pseudomonas, Bacillus, and Priestia, inhibited the growth of L. seditiosum by 50% to 80%, representing one of the first reported bacterial antagonisms for this neglected pathogen. All isolates were positive for at least two PGPTs, primarily due to mineralization of organic phosphate and the production of siderophores. The dual functional traits of isolated bacteria highlight their potential application in integrated forest protection strategies, particularly for the previously overlooked L. seditiosum pathosystem. Full article
(This article belongs to the Special Issue Plant Growth-Promoting Bacteria)
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19 pages, 6095 KB  
Article
Comparative Analysis of Potential Fire Behavior Among Three Typical Tree Species Fuel Loads in Central Yunnan Region
by Mingxing Liu, Yuanbing Yu, Weiming Chen, Ming Zhou, Jiaming Zhao, Biao Ye, Xilong Zhu, Shiying Xu, Chunyi He, Weili Kou and Qiuhua Wang
Forests 2025, 16(10), 1509; https://doi.org/10.3390/f16101509 - 24 Sep 2025
Viewed by 396
Abstract
Potential fire behavior varied significantly among tree species, directly influencing forest fire intensity and spread. To quantify these differences and evaluate species-specific fuel traits for fire management applications, this study conducted field surveys and sample collection in the Jin Dian Yuanbaoshan Forest Area, [...] Read more.
Potential fire behavior varied significantly among tree species, directly influencing forest fire intensity and spread. To quantify these differences and evaluate species-specific fuel traits for fire management applications, this study conducted field surveys and sample collection in the Jin Dian Yuanbaoshan Forest Area, Kunming, Yunnan Province. Using a combustion bed experiment, we simulated the burning behavior of Acacia dealbata, Alnus nepalensis, and Pinus armandii under windless conditions, recording ignition time, extinction time, flame height, spread rate, and calculating fire intensity. Comparative analysis revealed: (1) Fire intensity ranking: P. armandii needles > A. dealbata leaves > P. armandii branches > A. nepalensis leaves > P. armandii bark > A. dealbata branches > A. nepalensis branches > A. dealbata bark > A. nepalensis bark; (2) The biological firebreaks composed of A. nepalensis and A. dealbata in Yuanbaoshan exhibited effective flame-retardant performance; (3) Coarse woody fuels negatively affected prescribed burning intensity and effectiveness. By quantifying fire behavior differences among these species, this study provides scientific support for fuel management and fire-resistant species selection in central Yunnan, while offering practical guidance for prescribed burning strategies in the Jin Dian Yuanbaoshan Forest Area. Full article
(This article belongs to the Special Issue Fire Ecology and Management in Forest—2nd Edition)
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11 pages, 2464 KB  
Article
Needle Structure in Three Juniperus Taxa Indigenous to Slovakia
by Martin Galgóci, Andrej Kormuťák, Dušan Gömöry, Miroslav Klobučník, Peter Turis, Veronika Mistríková and Peter Boleček
Forests 2025, 16(9), 1406; https://doi.org/10.3390/f16091406 - 2 Sep 2025
Viewed by 614
Abstract
Needle structure was analyzed in three Juniperus communis taxa from different localities in central Slovakia. The main aim was to test the hybrid origin hypothesis of J. communis nothovar. intermedia (Schur) Nyman, defined as a cross between J. communis L. ssp. communis and [...] Read more.
Needle structure was analyzed in three Juniperus communis taxa from different localities in central Slovakia. The main aim was to test the hybrid origin hypothesis of J. communis nothovar. intermedia (Schur) Nyman, defined as a cross between J. communis L. ssp. communis and J. communis ssp. nana (Hook.) Syme. While DNA-based analyses remain the most reliable tool for inferring evolutionary history, comparative needle morphology can provide complementary evidence, including diagnostic traits for taxonomic delimitation. In this study, we evaluated three morphometric and sixteen anatomical needle traits, measured via microscopy in ten shrubs per taxon. The analyses indicated that most traits in nothovar. intermedia matched one of the parents, with only two traits proving strongly diagnostic, separating all three taxa: needle length, which showed an intermediate mean phenotype in nothovar. intermedia (R2 = 0.824, p = 0.011; between parents), and vascular bundle height, which displayed a transgressive pattern (R2 = 0.552, p = 0.031; between parents). Although the diagnostic value of individual traits for hybrid detection was generally weak, a phylogenetic network analysis based on six diagnostic traits that separated individuals of the parental taxa provided evidence for reticulate evolution. These results support the hybrid origin of J. communis nothovar. intermedia and highlight needle traits with potential value for distinguishing ssp. communis and ssp. nana in natural populations, which may assist in taxonomic delimitation and inform future conservation assessments. Full article
(This article belongs to the Section Forest Ecophysiology and Biology)
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21 pages, 2752 KB  
Article
Endophytic Bacterial and Fungal Communities of Spruce Picea jezoensis in the Russian Far East
by Nikolay N. Nityagovsky, Alexey A. Ananev, Andrey R. Suprun, Alina A. Dneprovskaya, Konstantin V. Kiselev and Olga A. Aleynova
Plants 2025, 14(16), 2534; https://doi.org/10.3390/plants14162534 - 14 Aug 2025
Viewed by 752
Abstract
A wide range of microorganisms, including endophytes, frequently interact with forest trees. The role of endophytes in industrial conifers has not been fully investigated. The Yezo spruce Picea jezoensis is widely used for logging in Russia and Japan. In this work, the endophytic [...] Read more.
A wide range of microorganisms, including endophytes, frequently interact with forest trees. The role of endophytes in industrial conifers has not been fully investigated. The Yezo spruce Picea jezoensis is widely used for logging in Russia and Japan. In this work, the endophytic communities of bacteria and fungi in healthy needles, branches, and fresh wood of P. jezoensis from Primorsky Territory were analyzed using metagenomic analysis. The results indicate that the diversity of endophytic communities in P. jezoensis is predominantly influenced by the specific tree parts (for both bacteria and fungi) and by different tree specimens (for fungi). The most abundant bacterial classes were Alphaproteobacteria, Gammaproteobacteria and Actinobacteria. Functional analysis of KEGG orthologs (KOs) in endophytic bacterial community using PICRUSt2 and the PLaBAse PGPT ontology revealed that 59.5% of the 8653 KOs were associated with plant growth-promoting traits (PGPTs), mainly, colonization, stress protection, bio-fertilization, bio-remediation, vitamin production, and competition. Metagenomic analysis identified a high abundance of the genera Pseudomonas and Methylobacterium-Methylorubrum in P. jezoensis, which are known for their potential growth-promoting activity in other coniferous species. The dominant fungal classes in P. jezoensis were Dothideomycetes, Sordariomycetes, and Eurotiomycetes. Notably, the genus Penicillium showed a pronounced increase in relative abundance within the fresh wood and needles of Yezo spruce, while Aspergillus displayed elevated abundance specifically in the fresh wood. It is known that some of these fungi exhibit antagonistic activity against phytopathogenic fungi. Thus, our study describes endophytic communities of the Yezo spruce and provides a basis for the production of biologicals with potential applications in forestry and agriculture. Full article
(This article belongs to the Special Issue Plant-Microbiome Interactions)
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13 pages, 354 KB  
Article
Effects of Feed Supplemented with Fermented Pine Needles (Pinus ponderosa) on Carcass Quality, Meat Quality, and Antioxidant Capacity of Growing–Finishing Pigs
by Wenfeng Ma, Zhuo Ma, Pei Mao, Xiaoli Zhang, Xiaohong Wu, Mengmeng Gao and Qiujue Wu
Foods 2025, 14(12), 2046; https://doi.org/10.3390/foods14122046 - 10 Jun 2025
Viewed by 1193
Abstract
The purpose of this study was to investigate the effects of fermented pine needles on the carcass traits, meat quality, and antioxidant capacity of finishing pigs. In total, 80 Duroc × (Landrace × Large white) crossbred pigs of approximately 4 months of age, [...] Read more.
The purpose of this study was to investigate the effects of fermented pine needles on the carcass traits, meat quality, and antioxidant capacity of finishing pigs. In total, 80 Duroc × (Landrace × Large white) crossbred pigs of approximately 4 months of age, with an initial body weight of 60.5 ± 2.5 kg, were randomly assigned to four experimental treatments, which were then denoted as the control treatment (basal diet), the fermented pine needle (FR) 1 treatment, the FR2 treatment, and the FR3 treatment (the pigs were fed the basal diet supplemented with 1.0, 2.0, and 3.0% fermented pine needles, respectively) for 55 d. The obtained results showed that, compared with the CON group, the fermented pine needle treatments increased the lean meat percentage, total antioxidative capacity, and superoxide dismutase activity in the serum and longissimus dorsi muscle. In addition, the treatments increased the mRNA expression levels of SOD1, catalase, and Nrf2 in the muscle and decreased the malondialdehyde activity in the serum and longissimus dorsi muscle and the Keap1 mRNA expression level. Compared with the CON and FR1 treatment, the FR2 and FR3 treatments increased springiness, serum GSH-Px activity, and longissimus dorsi muscle CAT activity, and decreased hardness, chewiness, gumminess, and cohesiveness. Moreover, compared with the CON treatment and other fermented pine needle treatments, the FR2 treatment not only significantly elevated the carcass weight, dressing percentage, pH24h, a* value (redness), and marbling scores of the finishing pigs, but also remarkably reduced the L* value (lightness), b* value (yellowness), and shear force in the meat quality. In conclusion, the experiment indicated that the addition of fermented pine needles to the diet has no negative impact on the carcass characteristics of finishing pigs and could improve the tenderness and freshness of the meat, as evidenced by the modified antioxidant enzyme activity and mRNA expression levels of antioxidant genes in the muscles of finishing pigs. Full article
(This article belongs to the Section Meat)
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23 pages, 19370 KB  
Article
Unraveling Phenological Dynamics: Exploring Early Springs, Late Autumns, and Climate Drivers Across Different Vegetation Types in Northeast China
by Jiayu Liu, Haifeng Zou, Yinghui Zhao, Xiaochun Wang and Zhen Zhen
Remote Sens. 2025, 17(11), 1853; https://doi.org/10.3390/rs17111853 - 26 May 2025
Cited by 1 | Viewed by 796
Abstract
Understanding plant phenology dynamics is essential for ecosystem health monitoring and climate change impact assessment. This study generated 4-day, 500 m land surface phenology (LSP) in Northeast China (NEC) from 2001 to 2021 using interpolated and Savitzky–Golay filtered kernel normalized difference vegetation index [...] Read more.
Understanding plant phenology dynamics is essential for ecosystem health monitoring and climate change impact assessment. This study generated 4-day, 500 m land surface phenology (LSP) in Northeast China (NEC) from 2001 to 2021 using interpolated and Savitzky–Golay filtered kernel normalized difference vegetation index (kNDVI) derived from MODIS. Spatial patterns, trends, and climate responses of phenology were analyzed across ecoregions and vegetation. Marked spatial heterogeneity was noted: forests showed the earliest start of season (SOS, ~125th day) and longest growing season (LOS, ~130 days), while shrublands had the latest SOS (~150th day) and shortest LOS (~96 days). Grasslands exhibited strong east–west gradients in SOS and EOS. From 2001 to 2021, SOS of natural vegetations in NEC advanced by 0.23 d/a, EOS delayed by 0.12 d/a, and LOS extended by 0.38 d/a. Coniferous forests, especially evergreen needle-leaved forests, exhibited opposite trends due to cold-resistant traits and an earlier EOS to avoid leaf cell freezing. Temperature was the main driver of SOS, with spring and winter temperatures influencing 48.8% and 24.2% of the NEC region, respectively. Precipitation mainly affected EOS, especially in grasslands. Drought strongly influences SOS, while precipitation affects EOS. This study integrates high-resolution phenology utilizing the kNDVI with various seasonal climate drivers, offering novel insights into vegetation-specific and ecoregion-based phenological dynamics in the context of climate change. Full article
(This article belongs to the Section Ecological Remote Sensing)
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15 pages, 2524 KB  
Article
Morpho-Anatomical Properties and Terpene Composition of Picea Omorika (Pančić) Purk. Needles from Bosnia and Herzegovina
by Biljana M. Nikolić, Zorica S. Mitić, Dalibor Ballian, Marina M. Todosijević, Jelena S. Nikolić, Stefan Ivanović and Vele V. Tešević
Forests 2025, 16(5), 791; https://doi.org/10.3390/f16050791 - 8 May 2025
Viewed by 834
Abstract
Picea omorika (Pančić) Purk., (Serbian spruce) is a relic, endemic, and vulnerable conifer that remains insufficiently studied to date. To the best of our knowledge, this is the first report on the morpho-anatomical and phytochemical diversity of needles from three populations in Bosnia [...] Read more.
Picea omorika (Pančić) Purk., (Serbian spruce) is a relic, endemic, and vulnerable conifer that remains insufficiently studied to date. To the best of our knowledge, this is the first report on the morpho-anatomical and phytochemical diversity of needles from three populations in Bosnia and Herzegovina. The length of two-year-old needles was measured with a digital caliper. The next six properties were measured based on cross-sections of the needles using a light microscope. An analysis of volatile compounds was carried out using gas chromatography coupled with mass spectrometry (GC-MS) and flame ionization detection (GC-FID). The highest values of needle traits were found in the Viogor population, with the lowest in the Tisovljak population, which was statistically confirmed. There was also a significant difference between needles from Bosnia and Herzegovina and those from Serbia. Bornyl acetate, camphene, limonene, and α-pinene were identified as the major terpene compounds. Multivariate analyses also suggested a tendency toward the separation of the Tisovljak population. A statistical comparison of three Bosnian and Herzegovinian and four Serbian populations (previously studied and published) revealed two distinct groups: (1) three Bosnian populations and the Vranjak population from Serbia, and (2) three populations from Serbia—Štula, Zmajevački Potok, and Mileševka Canyon. The general conclusions are that divergence in needle morpho-anatomy aligns with divergence in needle chemistry and that Bosnian and Herzegovinian populations are distinct from nearly all Serbian populations. Full article
(This article belongs to the Special Issue Specialized Metabolites and Structure of Woody Plants)
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22 pages, 1379 KB  
Review
Genetic and Genomic Tools in Breeding for Resistance to Fusarium Stalk Rot in Maize (Zea mays L.)
by Desmond Darko Asiedu and Thomas Miedaner
Plants 2025, 14(5), 819; https://doi.org/10.3390/plants14050819 - 5 Mar 2025
Cited by 3 | Viewed by 4987
Abstract
Maize (Zea mays L.) is the world’s most productive cereal crop, yet it is threatened by several diseases. Among them, Fusarium stalk rot (FSR) causes an average global yield loss of 4.5%. The mycotoxins deoxynivalenol, zearalenone, fumonisins, and moniliformin persist in grain and [...] Read more.
Maize (Zea mays L.) is the world’s most productive cereal crop, yet it is threatened by several diseases. Among them, Fusarium stalk rot (FSR) causes an average global yield loss of 4.5%. The mycotoxins deoxynivalenol, zearalenone, fumonisins, and moniliformin persist in grain and silage after harvest and pose a risk to human and animal health. This review describes the lifestyle of the fungal pathogens that cause FSR, studies how to optimize resistance evaluation, identifies quantitative trait loci (QTLs) and candidate genes (CGs), and, finally, considers the methods for selecting FSR resistance, especially through genomic selection. To screen maize genotypes for FSR resistance, several artificial inoculation methods have been employed in most studies, including toothpick insertion, ball-bearing pellets, root infection, and the oat kernel method. However, these methods have several limitations in effectively inducing FSR disease infection. Needle injection of inoculum into the stem is recommended, especially when combined with a quantitative or percentage scale because it effectively phenotypes maize populations for FSR resistance. Nine studies with larger populations (≥150 progenies) investigated the genetic architecture of FSR resistance. The inheritance is clearly quantitative. Four major QTLs and several minor QTLs are reported to confer resistance to FSR pathogens, and a few CGs have been identified. Genomic selection is recommended as an effective method for developing routinely FSR-resistant maize, but only two studies have explored this area. An omics analysis (proteomics, transcriptomics, and metabolomics) of the expression of candidate genes should validate their role in FSR resistance, and their use might accelerate selection. Full article
(This article belongs to the Special Issue Disease Resistance Breeding of Field Crops)
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23 pages, 8322 KB  
Article
Effects of Larch Woolly Adelgid Infestation on Morphological, Histological and Allelochemical Traits of European Larch Needles
by Katarzyna Dancewicz, Bożena Kordan, Marta Damszel, Iwona Sergiel, Magdalena Biesaga, Joanna Mroczek and Beata Gabryś
Insects 2024, 15(12), 938; https://doi.org/10.3390/insects15120938 - 28 Nov 2024
Viewed by 1490
Abstract
The study was carried out to assess the effect of the larch wooly adelgid Adelges laricis Vallot (Hemiptera: Adelgidae) infestation on its secondary host, the European larch Larix decidua Mill. Morphology and anatomy of adelgid-infested needles, and content of defense phenolic compounds including [...] Read more.
The study was carried out to assess the effect of the larch wooly adelgid Adelges laricis Vallot (Hemiptera: Adelgidae) infestation on its secondary host, the European larch Larix decidua Mill. Morphology and anatomy of adelgid-infested needles, and content of defense phenolic compounds including individual flavonoids isorhamnetin, kaempferol, quercetin, rutin, catechin, epicatechin, apigenin, ampelopsin and taxifolin, were analyzed. The amount of total phenols in needles from adelgid-infested twigs of L. decidua increased following the development of the A. laricis population, from the end of April until the end of June. The most abundant among flavonoids were the flavanols, mainly catechin and epicatechin, which predominated in the larch needles during the whole period of adelgid infestation. The content of catechin and epicatechin increased following the increase in the adelgid population number. An increase in content occurred also in flavanonols ampelopsin and taxifolin, while the content of the flavonol kaempferol decreased as the population number of A. laricis increased. The analysis of the anatomical structure of needles showed changes in the shape of the needles, the presence of a thicker layer of epicuticular waxes, and a higher number of mesophyll layers as a result of adelgid feeding. Full article
(This article belongs to the Section Insect Ecology, Diversity and Conservation)
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19 pages, 603 KB  
Article
Navigating Toward a Gender-Balanced Culture in Leadership Roles in Higher Tertiary Institutions (HTIs)
by Maria Krambia Kapardis and George Spanoudis
Adm. Sci. 2024, 14(11), 277; https://doi.org/10.3390/admsci14110277 - 26 Oct 2024
Cited by 1 | Viewed by 1868
Abstract
The European Commission (EC) and the United Nations advocate the importance of gender equality in their agendas and goals. More specifically, the EC has highlighted the importance of increasing women’s representation in leadership positions, yet in a minority of universities around the globe, [...] Read more.
The European Commission (EC) and the United Nations advocate the importance of gender equality in their agendas and goals. More specifically, the EC has highlighted the importance of increasing women’s representation in leadership positions, yet in a minority of universities around the globe, there is a gender imbalance. By excluding women from key academic leadership roles, a culture that superficially accepts women into roles that do not challenge the hierarchy is normalized, and a rubber stamp to hegemonic masculinity is established as typical conduct. This study utilizes data from a national survey distributed across all full-time academic and administrative staff in Cyprus’s 13 universities to examine the presence of gender disparities in leadership. The survey was designed based on a comprehensive review of the literature and pilot tested by experts in the field. It was then distributed by university rectors, reaching a total of 337 respondents. The data were analyzed to confirm that the characteristics of an extremely gendered environment, as established by researchers, are found in higher tertiary institutions (HTIs). Secondly, the authors found that the disparities between the leadership skills and traits held most prominently by women in HTIs, as opposed to their male counterparts, enhance the arguments put forward toward gender balance in leadership. Thirdly, the barriers holding women back from voicing their wishes to seek leadership roles in HTIs were identified. Finally, recommendations are made on how to overcome the androgenic environment, to move the needle and have more women seek leadership positions in a culture which preserves hegemonic masculinity. Changing this culture will navigate towards a more balanced working environment for staff and students, and can thus address ethical issues in a more inclusive and gender-balanced environment. Full article
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14 pages, 4597 KB  
Article
Needle and Branch Trait Variation Analysis and Associated SNP Loci Mining in Larix olgensis
by Ying Cui, Jiawei Yan, Luping Jiang, Junhui Wang, Manman Huang, Xiyang Zhao and Shengqing Shi
Int. J. Mol. Sci. 2024, 25(18), 10212; https://doi.org/10.3390/ijms251810212 - 23 Sep 2024
Viewed by 1426
Abstract
Needles play key roles in photosynthesis and branch growth in Larix olgensis. However, genetic variation and SNP marker mining associated with needle and branch-related traits have not been reported yet. In this study, we examined 131 samples of unrelated genotypes from L. [...] Read more.
Needles play key roles in photosynthesis and branch growth in Larix olgensis. However, genetic variation and SNP marker mining associated with needle and branch-related traits have not been reported yet. In this study, we examined 131 samples of unrelated genotypes from L. olgensis provenance trails. We investigated phenotypic data for seven needle and one branch-related traits before whole genome resequencing (WGRS) was employed to perform a genome-wide association study (GWAS). Subsequently, the results were used to screen single nucleotide polymorphism (SNP) loci that were significantly correlated with the studied traits. We identified a total of 243,090,868 SNP loci, and among them, we discovered a total of 161 SNP loci that were significantly associated with these traits using a general linear model (GLM). Based on the GWAS results, Kompetitive Allele-Specific PCR (KASP), designed based on the DNA of population samples, were used to validate the loci associated with L. olgensis phenotypes. In total, 20 KASP markers were selected from the 161 SNPs loci, and BSBM01000635.1_4693780, BSBM01000114.1_5114757, and BSBM01000114.1_5128586 were successfully amplified, were polymorphic, and were associated with the phenotypic variation. These developed KASP markers could be used for the genetic improvement of needle and branch-related traits in L. olgensis. Full article
(This article belongs to the Section Molecular Plant Sciences)
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15 pages, 2773 KB  
Article
Monitoring Eastern White Pine Health by Using Field-Measured Foliar Traits and Hyperspectral Data
by Sudan Timalsina, Parinaz Rahimzadeh-Bajgiran, Pulakesh Das, José Eduardo Meireles and Rajeev Bhattarai
Sensors 2024, 24(18), 6129; https://doi.org/10.3390/s24186129 - 23 Sep 2024
Cited by 2 | Viewed by 1574
Abstract
Canopy foliar traits serve as crucial indicators of plant health and productivity, forming a vital link between plant conditions and ecosystem dynamics. In this study, the use of hyperspectral data and foliar traits for white pine needle damage (WPND) detection was investigated for [...] Read more.
Canopy foliar traits serve as crucial indicators of plant health and productivity, forming a vital link between plant conditions and ecosystem dynamics. In this study, the use of hyperspectral data and foliar traits for white pine needle damage (WPND) detection was investigated for the first time. Eastern White Pine (Pinus strobus L., EWP), a species of ecological and economic significance in the Northeastern USA, faces a growing threat from WPND. We used field-measured leaf traits and hyperspectral remote sensing data using parametric and non-parametric methods for WPND detection in the green stage. Results indicated that the random forest (RF) model based solely on remotely sensed spectral vegetation indices (SVIs) demonstrated the highest accuracy of nearly 87% and Kappa coefficient (K) of 0.68 for disease classification into asymptomatic and symptomatic classes. The combination of field-measured traits and remote sensing data indicated an overall accuracy of 77% with a Kappa coefficient (K) of 0.46. These findings contribute valuable insights and highlight the potential of both field-derived foliar and remote sensing data for WPND detection in EWP. With an exponential rise in forest pests and pathogens in recent years, remote sensing techniques can prove beneficial for the timely and accurate detection of disease and improved forest management practices. Full article
(This article belongs to the Section Sensing and Imaging)
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15 pages, 10476 KB  
Article
Effects of Cold Acclimation on Morpho-Anatomical Traits of Heteroblastic Foliage in Pinus massoniana (Lamb.) Seedlings
by Yingying Xu, Haoyun Wang, Hongyang He and Feng Wu
Forests 2024, 15(9), 1560; https://doi.org/10.3390/f15091560 - 5 Sep 2024
Cited by 1 | Viewed by 1196
Abstract
Cold acclimation before winter has been shown to enhance the cold tolerance of evergreen conifers, including Pinus massoniana Lamb., a characteristic heteroblastic foliage tree in the conifer. In the initial growing season of P. massoniana, both primary needle seedlings (PNSs) and secondary [...] Read more.
Cold acclimation before winter has been shown to enhance the cold tolerance of evergreen conifers, including Pinus massoniana Lamb., a characteristic heteroblastic foliage tree in the conifer. In the initial growing season of P. massoniana, both primary needle seedlings (PNSs) and secondary needle seedlings (SNSs) are generated. While previous research has highlighted differences in the morphological structure and photosynthetic physiological functions of primary and secondary needles, their response to cold acclimation remains poorly understood. This study aimed to investigate the changes in morpho-anatomical structure, starch grain accumulation, and lignin deposition in the roots, stems, and leaves of PNSs and SNSs during cold acclimation using solid potassium iodide and hydrochloric acid phloroglucinol double-staining techniques. The results revealed that, during cold acclimation, the leaves and stems of PNSs exhibited sensitivity to low-temperature stress, resulting in noticeable shrinkage and fracture of mesophyll and cortical parenchyma cells. Furthermore, the early stages of cold acclimation promoted the accumulation of starch grains and lignin in the seedling tissues. In contrast to PNSs, the leaves and stems of SNSs exhibited a shorter cold acclimation period, attributed to the hydrolysis of starch grains in the epidermal cell walls and the transformation of xylem lignin, which supports cell structure stability and enhances cold resistance. In conclusion, these findings suggest that SNSs displayed a superior cold resistance potential compared to PNSs following cold acclimation, providing a significant theoretical basis for the further screening of cold-tolerant germplasm resources of P. massoniana and the analysis of cold resistance traits in heteroblastic foliage. Full article
(This article belongs to the Section Forest Ecophysiology and Biology)
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12 pages, 4904 KB  
Article
The Process of Winter Reddening Does Not Enhance Cold Resistance in Pinus massoniana Lamb. Seedlings
by Hongyang He, Yingying Xu, Shuangqin Xie, Xueying Li, Haoyun Wang, Yuanxiang Zhao and Feng Wu
Forests 2024, 15(9), 1527; https://doi.org/10.3390/f15091527 - 30 Aug 2024
Viewed by 1090
Abstract
Pinus massoniana Lamb. is an evergreen conifer; however, some current-year seedlings exhibit “winter reddening” at the onset of winter. The biological significance of this reddening is unclear. We examine the physiological responses of needles during the reddening process and explore the relationships between [...] Read more.
Pinus massoniana Lamb. is an evergreen conifer; however, some current-year seedlings exhibit “winter reddening” at the onset of winter. The biological significance of this reddening is unclear. We examine the physiological responses of needles during the reddening process and explore the relationships between physiological traits and seeding cold resistance. Based on needle color, we recognize non-reddened, partially reddened, and fully reddened needle stages. As reddening progresses, chlorophyll fluorescence parameters (maximum light energy conversion efficiency of photosystem II (PSII) photochemistry, PSII potential activity, effective photosynthetic quantum yield, non-photochemical and photochemical quenching coefficients, and actual quantum yield of PSII photochemistry) decrease, reducing photosynthetic efficiency. Concurrently, the proportion of regulated energy dissipation in quantum yield of PSII decreases, and that of PSII non-regulated energy dissipation increases. Antioxidant enzyme activities (catalase and peroxidase) and osmoregulatory substances (soluble sugars and proteins and proline) increase, and malondialdehyde levels and relative cell damage at 4 °C and −10 °C gradually increase. Although P. massoniana seedlings adapt to low-temperature environments as their needles redden by increasing antioxidant enzyme activities and osmoregulatory substances and by adjusting photosynthetic efficiency and light energy distribution, cell membrane damage persists. Cold resistance in P. massoniana seedlings is not fully established during winter reddening. Full article
(This article belongs to the Section Forest Ecophysiology and Biology)
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16 pages, 6716 KB  
Article
Effects of Low-Temperature Stress on Physiological Characteristics and Microstructure of Stems and Leaves of Pinus massoniana L.
by Hu Chen, Xingxing Liang and Zhangqi Yang
Plants 2024, 13(16), 2229; https://doi.org/10.3390/plants13162229 - 11 Aug 2024
Cited by 6 | Viewed by 2277
Abstract
Pinus massoniana L. is one of the most important conifer species in southern China and is the mainstay of the forest ecosystem and timber production, yet low temperatures limit its growth and geographical distribution. This study used 30-day-old seedlings from families of varying [...] Read more.
Pinus massoniana L. is one of the most important conifer species in southern China and is the mainstay of the forest ecosystem and timber production, yet low temperatures limit its growth and geographical distribution. This study used 30-day-old seedlings from families of varying cold-tolerance to examine the morphological traits of needles and stems, chlorophyll fluorescence characteristics, protective enzymes, and changes in starch and lignin under different low-temperature stresses in an artificial climate chamber. The results showed that the seedlings of Pinus massoniana exhibited changes in phenotypic morphology and tissue structure under low-temperature stress. Physiological and biochemical indexes such as protective enzymes, osmoregulatory substances, starch, and lignin responded to low-temperature stress. The cold-tolerant family increased soluble sugars, starch grain, and lignin content as well as peroxidase activity, and decreased malondialdehyde content by increasing the levels of actual photochemical efficiency (ΦPSII), electron transport rate (ETR), and photochemical quenching (qP) to improve the cold tolerance ability. This study provides a reference for the selection and breeding of cold-tolerant genetic resources of Pinus massoniana and the mechanism of cold-tolerance, as well as the analysis of the mechanism of adaptation of Pinus massoniana in different climatic regions of China. Full article
(This article belongs to the Special Issue Molecular Mechanisms of Rare Tree Species Response to Abiotic Stress)
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