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In response to concerns that increment coring with an increment borer might contribute to the dieback of pine trees in Thailand, this research aimed to evaluate the effects of increment coring on the growth of Khasi pine (Pinus kesiya Royle ex Gordon) at Doi Khuntan National Park in northern Thailand. Increment coring is commonly used in dendrochronology, but its impact on tree growth needs to be better understood. This study involved the selection of pine trees of varying diameters, categorizing them into control (uncored) and experimental (cored) groups. Subsequently, data were collected bimonthly from September 2018 to April 2023, except for interruptions from February 2020 to December 2021 due to the COVID-19 pandemic. Tree diameters at breast height were measured, and image analysis was used to monitor the wound healing every two months. A repeated-measures ANOVA was used to compare the growth of cored and uncored groups and the wound healing rates among small-, medium-, and large-tree groups. The growth of cored and uncored Khasi pines within the same and different diameter classes showed no significant differences nor did the wound healing rates. The findings indicated that increment coring had an insignificant impact on the tree growth across all diameter classes, with wounds healing effectively within 14 months. These results support the continued and safe use of increment coring with an increment borer as a non-destructive method for collecting tree-ring and wood samples for climate research and for providing valuable insights into forest management practices. [ABSTRACT FROM AUTHOR]

Communal forests are recognized to be of critical importance for the attainment of sustainable development goals (SDGs) but these are often understudied. Such is the case in Cordillera Central Range with its unique biodiversity and urban biodiversity sites requiring protection like the Alapang Communal Forest in Benguet, Northern Philippines. This study documented the floral diversity, carbon stock and the community perspectives as baseline for conservation. A total of 187 plant species belonging to 145 genera and 70 families were recorded with Pinus kesiya as the most dominant species. The forest exhibited high species richness, evenness, and diversity including indigenous, endemic species and some conservation important species. The total forest carbon was estimated at 6,931.44 t with an average of 192.54 t/ha. An interesting trade off was documented in the study with the pine dominated ridge stations having lower diversity but higher carbon stock while broad-leaf dominated depressed stations have higher diversity but lower carbon stock. Community surveys revealed the willingness to protect the forest due to its crucial role as a water source, highlighting its value and the importance of preservation. These findings offer empirical evidences on the role of communal forest on biodiversity conservation, carbon stock as well as forest goods and services. Locally, these findings offer insights for conservation and sustainable management of the Alapang Communal Forest and other local urban forests. [ABSTRACT FROM AUTHOR]

Phenylalanine ammonia lyase (PAL) is the rate-limiting and pivotal enzyme of the general phenylpropanoid pathway, but few reports have been found on PAL genes in Pinus yunnanensis. In the present study, three PAL genes were cloned and identified from P. yunnanensis seedlings for the first time, namely, PyPAL-1, PyPAL-2, and PyPAL-3. Our results indicated that the open-reading frames of PyPAL genes were 2184, 2157, and 2385 bp. Phylogenetic tree analysis revealed that PyPALs have high homology with other known PAL genes in other plants. In vitro enzymatic analysis showed that all three PyPAL recombinant proteins could catalyze the deamination of L-phenylalanine to form trans-cinnamic acid, but only PAL1 and PAL2 can catalyze the conversion of L-tyrosine to ρ-coumaric acid. Three PyPAL genes were expressed in different tissues in 1-year-old P. yunnanensis, and such genes had different expression patterns. This study lays a foundation for further understanding of the biosynthesis of secondary metabolites in P. yunnanensis. [ABSTRACT FROM AUTHOR]

Southeast Asia (SEA) has seen strong climatic oscillations and fluctuations in sea levels during the Quaternary. The impact of past climate changes on the evolution and distribution of local flora in SEA is still poorly understood. Here we aim to infer how the Quaternary climate change affects the evolutionary process and range shifts in two pine species. We investigated the population genetic structure and diversity using cytoplasmic DNA markers, and performed ecological niche modeling to reconstruct the species past distribution and to project range shift under future climates. We found substantial gene flow across the continuous distribution of the subtropical Pinus yunnanensis. In contrast, the tropical Pinus kesiya showed a strong population structure in accordance with its disjunct distribution across montane islands in Indochina and the Philippines. A broad hybrid zone of the two species occurs in southern Yunnan. Asymmetric introgression from the two species was detected in this zone with dominant mitochondrial gene flow from P. yunnanensis and chloroplast gene flow from P. kesiya. The observed population structure suggests a typical postglaciation expansion in P. yunnanensis, and a glacial expansion and interglacial contraction in P. kesiya. Ecological niche modeling supports the inferred demographic history and predicts a decrease in range size for P. kesiya under future climates. Our results suggest that tropical pine species in SEA have undergone evolutionary trajectories different from high latitude species related to their Quaternary climate histories. We also illustrate the need for urgent conservation actions in this fragmented landscape. [ABSTRACT FROM AUTHOR]

BACKGROUND: Methyl orange (MO) and methylene blue (MB) from aqueous solutions were effectively removed using thermally treated pine (Pinus kesiya) leaves. The influences of solution pH (2–10), contact time (10–240 min) and initial dye concentration (100–500 mg L−1) were found to be significant in the process of dye removal. The experimental data were fitted with four isotherm models (Langmuir, Freundlich, Sips and Temkin) and four kinetic models (Elovich, pseudo‐first‐order, pseudo‐second‐order and intraparticle diffusion). Some mechanisms of the MO and MB adsorption onto the adsorbent material were proposed and discussed. Results: Among the four isotherm models examined, the experimental data gave the best fit with the Langmuir model. The maximum Langmuir adsorption capacities were 136.99 mg g−1 for MO and 140.85 mg g−1 for MB. Kinetic studies illustrated that the biosorption of both dyes onto pine leaves aligns with Elovich, pseudo‐first‐order, pseudo‐second‐order and intraparticle diffusion models. Thermodynamic studies showed that the uptake of the two dyes was regulated by physisorption, and it was spontaneous and endothermic in nature. Electrostatic interactions, as well as other noncovalent forces such as π–π interactions and hydrogen bonds, were mechanisms of dye adsorption on heat‐treated pine leaf biomass. Conclusion: The present study suggests that pine leaves could be a potential biosorbent for wastewater treatment due to their high availability and production, resulting in several environmental advantages. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

A total of thirty-five wood-rotting fungi were documented from living Pinus kesiya trees, woody debris and cones. Wood-rotting fungi inhabiting P. kesiya were all representatives of the Division Basidiomycota and are distributed under twenty families and twenty-nine genera. The Family Polyporaceae was the most dominant taxa. Two edible wood-rotting fungi: Auricularia auricula-judae and Schizophyllum commune were recorded from the study. Nine species were found growing only on logs, seven on stumps, three on cones and two on living P. kesiya trees. The remaining thirteen species were collected from more than one type of substrata. Seven wood-rotting fungi were host specific and were found growing only on P. kesiya host. It was observed from the study that majority of the species collected from P. kesiya woody debris were also found growing on the dead woody debris of other host tree species present in the forest stands studied. One species, Coltriciella dependens was found growing only at the base of the partially burnt barks of living P. kesiya trees. [ABSTRACT FROM AUTHOR]

In response to concerns that increment coring with an increment borer might contribute to the dieback of pine trees in Thailand, this research aimed to evaluate the effects of increment coring on the growth of Khasi pine (Pinus kesiya Royle ex Gordon) at Doi Khuntan National Park in northern Thailand. Increment coring is commonly used in dendrochronology, but its impact on tree growth needs to be better understood. This study involved the selection of pine trees of varying diameters, categorizing them into control (uncored) and experimental (cored) groups. Subsequently, data were collected bimonthly from September 2018 to April 2023, except for interruptions from February 2020 to December 2021 due to the COVID-19 pandemic. Tree diameters at breast height were measured, and image analysis was used to monitor the wound healing every two months. A repeated-measures ANOVA was used to compare the growth of cored and uncored groups and the wound healing rates among small-, medium-, and large-tree groups. The growth of cored and uncored Khasi pines within the same and different diameter classes showed no significant differences nor did the wound healing rates. The findings indicated that increment coring had an insignificant impact on the tree growth across all diameter classes, with wounds healing effectively within 14 months. These results support the continued and safe use of increment coring with an increment borer as a non-destructive method for collecting tree-ring and wood samples for climate research and for providing valuable insights into forest management practices.

Due to the high uncertainty of tree crown biomass modeling, it is crucial to estimate individual tree crown biomass by incorporating competition factors using mixed effect models. The crown biomass of 128 sampling trees was investigated at three typical sites of the natural Pinus kesiya forest in Pu'er city of Yunnan province, China. Considering the random effects of the site index and incorporating competition factors, the branch and needle biomass models were constructed using the nonlinear mixed effect model. The results showed that: (1) the mixed effects models, including the fixed effect of competition factors, had a better fitting performance than the ordinary mixed model for branch biomass, however, mixed effects models without the fixed effect of competition factors had the best-fit performance for the needle biomass; (2) mixed effect models incorporating competition factors had better prediction ability because of the highest precision. The increase in accuracy varied from 49.87 to 70.27% for branch biomass and from 66.19 to 66.57% for needle biomass. Mixed-effects models, considering site effect and competition factors, may provide a flexible and powerful tool for individual crown biomass estimation. [ABSTRACT FROM AUTHOR]

This study evaluates the structural performance of Pinus sylvestris (Scots Pine) when applied as a structural beam, which focuses on flexure and shear performances. Testing and mathematical evaluation were necessary to determine the properties of this material in order to investigate its performance as a structural beam. Following the prescribed sizes indicated in ASTM D905 and ASTM D198, specimens for shear and flexure were manufactured with the application of polyvinyl acetate adhesive between each lamina within each test sample. These specimens were tested using static bending and shear/delamination tests in accordance with the two standards, and results were analyzed quantitatively using the statistical methods and internationally accepted methods indicated in the Design Standard of Philippine Timber and the National Structural Code of the Philippines (NSCP). The analysis of results has shown that upon investigation of Pinus sylvestris glulam with Polyvinyl acetate (PVAc) adhesive manufactured using the available technology in the Philippines, it is not suitable for construction or any uses that involve load-bearing capabilities. Further investigation is recommended to be conducted in the future in relation to this study. The conclusions made in this study may be used for academic references pertaining to the use of this wood species. [ABSTRACT FROM AUTHOR]

Known for being the City of Pines, Baguio has created a reputation as recreation refuge from the hustle and bustle of Metro Manila and other neighboring urban centers. But because of its cool climate and popularity as a tourist destination, Baguio in itself is deluged with impending problems of urbanity and development. Spaces that were previously green are continuously converted into built areas. A few years ago, an issue arised regarding the conversion of a popular mall's open space planted with the fully grown specimens of Baguio's tree symbol--the Benguet pine or Pinus kesiya. The space was to be converted into an additional building wing, which drew strong reactions from concerned residents and environmental groups. The conversion was conducted and that resulted to mixed reactions regarding the importance of the pine tree in Baguio's remaining open spaces. The research explores the perception of Baguio space users on the state of its urban green open spaces and qualify the importance of the symbolic Benguet pine's presence in urban green, hence this research aimed to know more about this matter. First, some architects and other design professionals were consulted as prequalification to enumerate which Baguio open spaces are perceived as green open space. They were also inquired which of these spaces exhibited the most distinct presence of the iconic pine tree. Ten parks and public spaces were short listed. A survey regarding the 10 prequalified Baguio City open spaces and the Benguet pine was then formulated and disseminated to people who are familiar with Baguio, mostly residents, through an online platform. Results showed which open spaces are popularly visited and perceived green by users. The same survey also indicated that the most popular and green perceived public open spaces are also said to have the most visible presence of the Benguet pine tree, indicating that in the public's perception, the Benguet pine's presence is particularly relevant in the major green spaces around Baguio City. [ABSTRACT FROM AUTHOR]

There is still limited information on how genetic introgression impacts morphological variation and population fitness in long-lived conifer species. Two closely related pine species, Pinus kesiya Royle ex Gordon and Pinus yunnanensis Franch. are widely distributed over Southeast Asia and Yunnan province of China, with a large spatial scale of asymmetric genetic introgression and hybridization, and form a hybrid lineage, P. kesiya var. langbianensis, where their ranges overlap in southeast Yunnan. We compared seed trait variation and germination performance between hybrids and parental species and characterized environmental gradients to investigate the genetic and ecological evolutionary consequences of genetic introgression. We found that seed width (SW) differed significantly among the three pines, and all the seed traits were significantly negatively correlated with latitude and associated with the mean temperatures of the driest and wettest quarters. A higher germination fitness of hybrids was detected at a low temperature, indicating that they had better adaptability to temperature stress than their parental species during the germination process. Our results suggest that environmental factors shape seed phenotypic variation in the pine species and that genetic introgression significantly affects seed germination fitness. Therefore, assisting gene flow in natural forest populations might facilitate their adaptation to climate change. [ABSTRACT FROM AUTHOR]

In order to project the climate fluctuations back to the past and predict the changes in the future, climate variability inducing annual and intra-annual ring formation in Khasi pines (Pinus kesiya) growing in northern Thailand was investigated and the past climate was reconstructed. Annual and intra-annual rings from several Khasi pines were identified using the techniques of cross-matching and cross-dating. All of the 88 wood core samples were successfully cross-dating with a 118-year growing period from AD 1898 to AD 2015. The annual growth was significantly affected by the mean temperature in April (r = -0.423) and total rainfall in March-April (r = 0.371). The equatorial sea surface temperature during August-November of the previous year also significantly stimulated the growth of these pines (r = 0.370). Regression analysis indicated that the maximum temperature influenced the formation of intra-annual rings and could explain 48.1% of the variance in the intra-annual rings. It was also found that the total rainfall during the summer period of March-April declined from 68.1 mm in AD 1898 to 54.1 mm in AD 2015 with the average of total rainfall of 60.4 mm in the period. The rainfall projected in AD 2065 was around 48.1 mm, while the mean temperature in April gradually increased from 30.10 °C in AD 1898 to 30.45 °C in AD 2015 with the average temperature of 30.33 °C and should continuously increase to 30.60 °C in AD 2065 [ABSTRACT FROM AUTHOR]

There is still limited information on how genetic introgression impacts morphological variation and population fitness in long-lived conifer species. Two closely related pine species, Pinus kesiya Royle ex Gordon and Pinus yunnanensis Franch. are widely distributed over Southeast Asia and Yunnan province of China, with a large spatial scale of asymmetric genetic introgression and hybridization, and form a hybrid lineage, P. kesiya var. langbianensis, where their ranges overlap in southeast Yunnan. We compared seed trait variation and germination performance between hybrids and parental species and characterized environmental gradients to investigate the genetic and ecological evolutionary consequences of genetic introgression. We found that seed width (SW) differed significantly among the three pines, and all the seed traits were significantly negatively correlated with latitude and associated with the mean temperatures of the driest and wettest quarters. A higher germination fitness of hybrids was detected at a low temperature, indicating that they had better adaptability to temperature stress than their parental species during the germination process. Our results suggest that environmental factors shape seed phenotypic variation in the pine species and that genetic introgression significantly affects seed germination fitness. Therefore, assisting gene flow in natural forest populations might facilitate their adaptation to climate change.

Coltriciella dependens a new record of wood rotting fungi is being reported on partially burnt bark of living Pinus kesiya from Meghalaya, India. It is the first record of the genus Coltriciella as well. Macro-microscopical features, photographs, distribution patterns and ecology are discussed.

In this work, the central composite design in response surface methodology by the Design-Expert software was used for optimizing the removal of Pb(II) ions from aqueous solution by pine leaves (Pinus kesiya). Effects of pHsolution, adsorption time and initial Pb(II) ions concentration on adsorption capacity were investigated. Experimental data were fitted by using five nonlinear isotherm models including Langmuir, Freundlich, Sips, Temkin and Dubinin-Radushkevich. The maximum Pb(II) adsorption capacity (qmax) estimated from the Langmuir isotherm model was 31.04 mg/g, which is higher than other biomaterials such as barley straw, Cucumis sativus peel, coconut tree sawdust, etc. Kinetic studies indicated that the uptake of Pb(II) occurred on the Elovich model within two stages. Thermodynamic studies at different temperatures showed the biosorption to be endothermic and spontaneous. The study concluded that P. kesiya can be a good adsorbent for removing Pb(II) from aqueous solution. [ABSTRACT FROM AUTHOR]

Aims: Pinus yunnanesis is commercially, culturally and economically important, but there is a lack of ecological data on its role in stand dynamics. Our aims are to clarify the structure, composition, regeneration and growth trends of primary mature P. yunnanensis forests. Study area: The Tianchi National Nature Reserve in the Xuepan Mountains, Yunlong County, northwestern Yunnan, China. Methods: We investigated forests containing P. yunnanensis, measured tree ages and analyzed the data. Results: Six forest types were identified: (1) coniferous forest: Pinus yunnanensis (Type 1); (2) mixed coniferous and evergreen broad-leaved forest: P. yunnanensis-Lithocarpus variolosus (Type 2); (3) mixed coniferous and deciduous broad-leaved forest: P. yunnanensis-Quercus griffithii (Type 3); (4) mixed evergreen broad-leaved and coniferous forest: Castanopsis orthacantha-P. yunnanensis-Schima argentea (Type 4); (5) mixed coniferous, evergreen and deciduous broad-leaved forest: Pinus yunnanensis-Schima argentea-Quercus griffithii (Type 5); (6) mixed coniferous and evergreen broad-leaved forest: Pinus armandii-Quercus rehderiana-Pinus yunnanensis (Type 6). The size- and age-structure and regeneration patterns of P. yunnanensis were highly variable within these six forest types. P. yunnanensis regeneration was well balanced in forest Type 1 as compared to the other five types. All six forest types were identified as rare and old-growth with P. yunnaensis trees reaching ages of more than 105 years (a maximum age of 165 years with a diameter 116 cm at breast height) except for the Type 4 forest (a 90-year-old stand). Growth rates of P. yunnanensis, based upon ring width measurements, were high for the first 10 years, then declined after the 10th year. In contrast, basal area increment (BAI) increased for the first 25 years, plateaued, and only declined as trees became older. Trees in the older age classes grew more quickly than younger trees at the same age, a consequence of either site quality or competitive differences. The BAI of P. yunnanensis in all age classes in the Tianchi National Nature Reserve was much higher than those of the secondary and degraded natural P. yunnanensis forests of other areas. Conclusions: The P. yunnanensis forests of the Tianchi area appear to be some of the last remnants of primeval and old-growth forests of this species. These forests are structurally diverse and contain a rich diversity of overstory, mid-story, and understory species. [ABSTRACT FROM AUTHOR]

Pinus yunnanensis var. Tenuifolia is an important species of timber and grease in southern China, but the characteristics of the soil microbial community in P. yunnanensis var. natural secondary forests are still poorly understood. Using a fumigation-extraction method and phospholipid fatty acid (PLFA) analysis, we study microbial biomass and community composition in the topsoil (0-10 cm) of three types of secondary forests (PYI, PYII, PYIII) dominated by P. yunnanensis var. to varing degrees. Microbial biomass carbon and nitrogen, total PLFA, and PLFA contents of bacterial, fungal, and arbuscular mycorrhizal fungi were significantly lower in PYI than PYII or PYIII, and there were significant differences in the monounsaturated/saturated fatty acid ratio among the tested forests. Principal component analysis indicated that the soil microbial community structure of the tested forests differed significantly. The changes in soil microbial biomass and community composition were positively correlated with soil water content, pH, organic matter (SOM), total nitrogen (TN), and total phosphorus. Season did not significantly affect the soil microbial community structure, but significantly affected soil microbial biomass, SOM, and TN, which were higher in the dry season than in the wet season. [ABSTRACT FROM AUTHOR]

Background: Pines are widely distributed in the Northern Hemisphere and have a long evolutionary history. The availability of transcriptome data has facilitated comparative transcriptomics for studying the evolutionary patterns associated with the different geographical distributions of species in the Pinus phylogeny. Results: The transcriptome of Pinus kesiya var. langbianensis was sequenced using the Illumina HiSeq 2000 platform, and a total of 68,881 unigenes were assembled by Trinity. Transcriptome sequences of another 12 conifer species were downloaded from public databases. All of the pairwise orthologues were identified by comparative transcriptome analysis in 13 conifer species, from which the rate of diversification was calculated and a phylogenetic tree inferred. All of the fast-evolving positive selection sequences were identified, and some salt-, drought-, and abscisic acid-resistance genes were discovered. Conclusions: mRNA sequences of P. kesiya var. langbianensis were obtained by transcriptome sequencing, and a large number of simple sequence repeat and short nucleotide polymorphism loci were detected. These data can be used in molecular marker-assisted selected in pine breeding. Divergence times were estimated in the 13 conifer species using comparative transcriptomic analysis. A number of positive selection genes were found to be related to environmental factors. Salt- and abscisic acid-related genes exhibited different selection patterns between coastal and inland Pinus. Our findings help elucidate speciation patterns in the Pinus lineage. [ABSTRACT FROM AUTHOR]

The objective of this study is to map the spatial distribution of the aboveground biomass (AGB, tC/ha) storage of the Pinus kesiya Royle ex Gordon (Benguet pine) forest of Sagada, Mt. Province, Philippines by integrating Landsat image and the forest cover map. The data was obtained from 66 plots that were established in the different Benguet pine stands in Sagada. The AGB was estimated using the Digital Numbers (DN) and Normalized Difference Vegetation Index (NDVI) values (with filter and with no filter). The estimated aboveground biomass (AGB) density of the Benguet pine was determined to be 249.66 tonnes/ha corresponding to 112.35 tonnesC/ha. [ABSTRACT FROM AUTHOR]

Cephalcia chuxiongica Xiao is one of the most dangerous defoliators of Pinus yunnanensis and other pine species in Yunnan province, resulting in serious losses. Its distinguishing characteristics are the females' aggregation oviposition and larvae's aggregation feeding. In order to explore the mechanism of aggregation oviposition in this sawfly, preliminary olfactory bioassay was conducted in laboratory. In in-cage choice tests, on average vast majority gravid females selected the shoots that had been loaded and oviposited by a 'pioneer' female. In one-choice tests in laboratory by a Y-tube olfactometer, the gravid females were attracted by the odors of eggs-carrying shoots (PE), shoots with one delivering female and her eggs (PGE), needles' extract (NE), and fresh eggs' eluent (EL); the virgin females were attracted by odors of fresh needles (P), PE, PGE, and NE, but repelled by odors of virgin and gravid females. In two-choice tests, the odors were tested in pairs for gravid females. When compared with odors of gravid females (G) or P, gravid females showed significantly more tendency to odors of PE or PGE. When given odors EL vs. NE, gravid females preferred the odors of NE, but they did not make obvious selection between G vs. P, and PE vs. PGE. Based on the results, our conjectures were: (1) Delivery female, as a pioneer, can summon her conspecific gravid females to aggregate in the same pine shoot; (2) Pine needles' odors were attractive for both the virgin and gravid females; (3) Gravid females could be attracted by odors released by the pioneer gravid females; (4) The olfactory sensation of the females may be changed by mating. [ABSTRACT FROM AUTHOR]

Abstract: Sydowia polyspora occurs often as an epiphyte or endophyte of conifers and is widely distributed around the world. It is also reported as a fungus associated with bark beetles. In this study, based on ITS sequence data and morphological characteristics, 14 strains collected from the beetle bodies and galleries of Tomicus minor and Tomicus yunnanensis infesting Pinus yunnanensis in Southwestern China were identified as S. polyspora. To assess the virulence of S. polyspora to P. yunnanensis, pathogenicity tests were conducted by inoculating the fungus in the stems and on needles of P. yunnanensis. The results after 30 days showed that the lesion lengths in the phloem after inoculation with S. polyspora were significantly longer than for the control. In addition, the fungus caused partly distinct chlorisis or discolouration of needles 14 days after inoculation. This suggests that S. polyspora is able to colonize stem phloem and pine needles of P. yunnanensis and thus may cause secondary damages to this host after being spread with bark beetles. [ABSTRACT FROM AUTHOR]

Bark beetles (Scolytidae) are widely distributed in the world. In Yunnan Province, the southwest of China, Yunnan pine (Pinus yunnanensis) has been seriously damaged by bark beetles. Because Yunnan pine is one of the most important afforestation tree species in Yunnan Province, the government has implemented a series of measures to protect Yunnan pine from being damaged by bark beetles. However, it is very difficult to identify the bark beetle pest in the early stage due to the hysteresis symptoms. Based on the hypothesis of delay effect between drought and insect pests, one of the remote sensing drought indices TVDI (temperature vegetation dryness index) was proposed to predict the damage of bark beetles. TVDI was estimated by NDVI (normalized difference vegetation index) and brightness temperature in Shilin County where large area was damaged by drought and bark beetles. NDVI and brightness temperature were derived from long-term Landsat images from 2009 to 2014. The damage rating of Yunnan pine forests attacked by bark beetles was divided into 4 categories, including the healthy forests, lightly damaged forests, moderately damaged forests and severely damaged forests. TVDI was related to different damage ratings, and the relationship between TVDI and the difference of NDVI (dNDVI) before and after the Yunnan pine forest attacked by bark beetles was analyzed to effectively predict the possible occurrence of pests in the future. The dNDVI was used to stand for the real damage degree of Yunnan pine forests. To evaluate the relationship, lightly damaged forest polygons were selected in this study. However, only the pixels with dNDVI greater than 0 were extracted to eliminate those areas without being affected by insects in each polygon, and the larger polygon was split into many small polygons. In order to eliminate the difference of dNDVI range between different years, the maximum and minimum normalization method was used to normalize dNDVI. Results showed that the area and the number of attacked forest patches by beetles were declining from 2010 to 2015. TVDI in the healthy forest patches (0.657±0.114) was higher than that in the pest infected forest patches. Whereas, the value of TVDI (0.530±0.112) of the lightly damaged Yunnan pine forest patches was not significantly higher than that of the moderately damaged Yunnan pine forest patches (0.498±0.097) (P>0.05), but it was significantly higher than that of the severely damaged Yunnan pine forest patches (0.449±0.113) (P<0.05). And no significant difference was found between moderately and severely damaged Yunnan pine forests (P>0.05). Smaller TVDI generally corresponded to more serious degree of pest damages. The time series of TVDI spatial distribution also showed that TVDI was gradually increasing in recent years, while the pest infected area and the mean damage degree declined. Furthermore, TVDI was negatively correlated with dNDVI during the period of 2011, and a linear regression model could successfully express the relationship between them with the R2 of 0.322. The linear model could predict the dNDVI in 2012 with the root mean square error (RMSE) of 0.237. However, the regression line deviated from 1:1 line, and other factors should be considered in the future, including site conditions, stand structure, and forest growth. Overall, the relatively humid areas were more likely to have bark beetle pests during the drought periods. According to the spatial distribution of TVDI, the area with lower TVDI would be prone to be infected by insect pests. However, the prediction of the spatial distribution of bark beetles pest still needs further study. Other than TVDI, the model should involve other factors. This study proposes constructive suggestion on the timely releasing pest monitoring information. [ABSTRACT FROM AUTHOR]

Reforestation has been widely adopted to restore soil fertility and ecosystem service function in the rocky desertification region of southwestern China. However, there has been limited research concerning the stoichiometry of carbon (C), nitrogen (N), and phosphorus (P) and nutrient resorption rate of plantations in karst ecosystems. In this study, we selected plantations of Pinus yunnanensis Franch. (PY) and Eucalyptus maideni F. Muell. (EM) in Yunnan Province. The C, N, and P concentrations and the C:N:P stoichiometry in different soil layers (0-10 cm, 10-20 cm, and 20-30 cm) were examined. The nutrient limitation and nutrient resorption efficiency were also analyzed. The leaf C and N concentrations in the PY plantation were higher than that in the EM plantation; the P concentration demonstrated the opposite trend, both in green and senesced leaves. Soil C, N, and P concentrations in the EM plantation were much greater than in the PY plantation at all three depths and decreased with the depth of the soil. In addition, the high ratios of C:P, N:P, C:Available P, and N:Available P in soil coupled with the ratios of N:P in leaves indicate that the EM plantation has a greater P deficiency than the PY plantation. In the EM plantation, the relatively low P concentrations in senesced leaves indicates efficient TP (Total phosphorus) resorption, which highlights that the high reuse proficiency of P could have favored moderating P limitation in the karst ecosystem. This research aids in understanding the stoichiometric characteristics that mediate forest properties, and provides a basis for management of vegetation in karst ecosystems. [ABSTRACT FROM AUTHOR]

The relationship between biodiversity and biomass is an essential element of the natural ecosystem functioning. Our research aims at assessing the effects of species richness on the aboveground biomass and the ecological driver of this relationship in a primary Pinus kesiya forest. We sampled 112 plots of the primary P. kesiya forests in Yunnan Province. The general linear model and the structural equation model were used to estimate relative effects of multivariate factors among aboveground biomass, species richness and the other explanatory variables, including climate moisture index, soil nutrient regime and stand age. We found a positive linear regression relationship between the species richness and aboveground biomass using ordinary least squares regressions. The species richness and soil nutrient regime had no direct significant effect on aboveground biomass. However, the climate moisture index and stand age had direct effects on aboveground biomass. The climate moisture index could be a better link to mediate the relationship between species richness and aboveground biomass. The species richness affected aboveground biomass which was mediated by the climate moisture index. Stand age had direct and indirect effects on aboveground biomass through the climate moisture index. Our results revealed that climate moisture index had a positive feedback in the relationship between species richness and aboveground biomass, which played an important role in a link between biodiversity maintenance and ecosystem functioning. Meanwhile, climate moisture index not only affected positively on aboveground biomass, but also indirectly through species richness. The information would be helpful in understanding the biodiversity-aboveground biomass relationship of a primary P. kesiya forest and for forest management. [ABSTRACT FROM AUTHOR]

Some imported guitars and others made in Zambia exhibit poor sound quality and properties. Zambia grown timbers were evaluated for their suitability as tonewoods. Pinus kesiya was suitable for soundboard as it had brighter appearance and best radiation coefficient 7.3 m4 s-1 kg. Its lower impedance 2733 Nmm2 s m3 gives better sustain. Pterocarpus angolensis was used for the back and sides as it was very stable, volumetric shrinkage 5.4%, and low impedance, 2,298 Nmm2 s m3 which reduced loudness. This species was also used for the neck. Baikiaea plurijuga was employed in fretboard and bridge construction as it was appreciably hard with Brinell hardness rating of 6.05 kN. A guitar made using the selected timbers was tested qualitatively. The Reference and the Experimental guitar attained the same score demonstrating improvements attributable to systematic wood selection. The study established that the quality of locally made guitars could be improved significantly if luthiers adopt appropriate wood selection criteria. [ABSTRACT FROM AUTHOR]

Wood as a renewable engineering material has widely been used for structural purpose for decades, but its static bending modulus of elasticity ( E ) has not been seriously researched in large-scale relative humidity fluctuant environment. This paper presents an experimental and numerical study for the assessment of E of Pinus yunnanensis as a function of moisture content and its distribution in high relative humidity environment. For this, a moisture transfer model based on a multi-phase-type approach and a classical theory of laminated plate was used. The experimental results indicated that the predicted E had good agreement with measured data making it possible for researchers, designers, and industry in the field of wood mechanics and products to directly obtain the wood E by way of calculation. Furthermore, it was also found that there was a decrease in E in the short term when the environment relative humidity increased substantially. This phenomenon reminds designers and industry in the field of wood mechanics and products that using so-called E with equilibrium moisture content as the actual mechanical value of structural-use wood may bear a potential risk. [ABSTRACT FROM AUTHOR]

Research on tree response to pest attacks under drought and heat stress is crucial for predicting the effect of climate change on forest pests and tree health. In this work, we studied the influence of severe water stress on the resistance of Pinus yunnanensis to inoculations of Grosmannia yunnanensis, a pathogenic fungus associated with the aggressive bark beetle, Tomicus yunnanensis. Experiments were performed in two plots, one located at the top of a hill and the other at the foot of a hill, in Xiaojiu, Yunnan, China, from May to September 2010 and March to April 2012. Measurements of soil and needle water content and predawn needle water potentials confirmed that severe droughts occurred during these periods. Maximum water stress intensity even occurred in 2010 during the typical rainy season. Following low-density inoculations, the reaction zone length and fungal growth were measured in the phloem. Sapwood blue staining and total sapwood occlusion were quantified following fungal mass inoculations. Our results suggest that severe water stress has a negative impact on a tree's resistance to G. yunnanensis. By comparing our results to previous work performed from 1997 to 1999 on the same tree species, and in the same locality under mild water stress, we concluded that drought had opposite effects on tree resistance above and below a certain threshold of predawn needle water potential. The threshold, corresponded to maximum efficiency for tree defence mechanisms, was visible in our results, and was estimated to be approximately -1.1 MPa to -1.2 MPa for P. yunnanensis under local conditions. We suggest that the existence of such a threshold of water stress intensity may be viable for any conifer undergoing biotic aggressions and, specifically, bark beetle attacks. [ABSTRACT FROM AUTHOR]

Tree breeders face the problem of negative correlations between wood properties and growth traits. It is necessary to overcome this difficulty in order to obtain promising genotypes. The selection index is one of the helpful tools in this process, because it allows multiple features of interest to be selected. In this study, a multiple trait selection index for Khasi pine (Pinus kesiya Royle ex Gordon) grown in Malawi was developed. Data on wood properties and growth traits were collected from six families of P. kesiya at the age of 30 years. The breeding objective was defined in terms of wood stiffness, wood strength and volume. Selection traits included in the index were wood stiffness (MoE), wood strength (MoR), volume (Vol.), wood density (WD), and diameter at breast height (DBH). The index was termed as IT = -80.36 MoE - 14.60 MoR + 132.07 Vol. + 4858.09 WD - 7.56 DBH. The accuracy of the index was 98.8% and the correlation between the index and the aggregate breeding objective was 0.994. A genetic gain of 16.7% for volume, 14.8% for wood stiffness and 13.2% for wood strength would be expected from a standardized 10% selection intensity. Therefore, application of the developed selection index is necessary in order to increase the efficiency of the Pinus kesiya breeding programme in Malawi. [ABSTRACT FROM AUTHOR]

A layer of shading (50.3 %NS), two layer of shading (15 %NS), three layer of shading (4.2 mNS) and natural light (100 m NS) were set up to 4 different light intensity, in order to research the seedling survival rate and root growth of Pinus yunnanensis var. tenuifolia of one-month seedling and half a year seedling and their response characteristics under different light intensity. The results showed that the seeding growth of one-month and half a year of Pinus yunnanensis var. tenuifolia, survival rate, diameter growth in 100 m light reached maximum and gradually decreased with increasing shading intensity; 50.3 m in the light of Pinus yunnanensis var. tenuifolia from one-month seedling and half a year seedling, the height growth reached the maximum. The different light intensity had significant effects on the root growth of Pinus yunnanensis var. tenuifolia, total root length, total root number, total root surface area and root volume of seedlings which decreased with the light intensity decreased. Natural light (100 m NS) were beneficial to the root growth and development of Pinus yunnanensis var. tenuifolia. [ABSTRACT FROM AUTHOR]

The phenotypic diversity indexes of needle Aaits were compared among the diferent stem types of Pinus yunnanensis Franch. . Thestraight stem types and twisted or crooked stem types were collected as the research objects. The results showed that the diversity index anc the coefficient of variation of general in stand were the greatest among general in stand，straight type and twisted/crooked type. The diversity index was the greatest for general in canopy and was the lowest for the twisted/crooked type in canopy，and the coefficient of variation was the greatest for the straight type in canopy. The diversity index and the coefficient variation of regeneration layer in general were the greatest，followed by the twisted/crooked type，and the straight type was the lowest in regeneration layer. The coefficient of variation of canopy was greater than regeneration layer for straight type，but tlie diverity index was the contrar tendency. The diverity index and the coefficient of variation of regeneration layer were greater tlian canopy for the twisted//crooked type. Therefore，the undamaged ways should be given priority tc the germplasmresources preservation of P. yunnanensis. Keeping straight plants and harvesting twisted/crooked plants will be a better relective cutting way. [ABSTRACT FROM AUTHOR]

The bulk of exotic forest plantations and sawmills in Zambia are within the reach of air pollutants from mines on the Copperbelt province. Up to 60% of every cubic meter of the timber processed is waste, of which 0,12 m3 is sawdust. Sawdust is largely used for various surface amendments and as a source of energy, but the dangers it poses to users are not known. Heavy metals assimilated by trees or adsorbed by sawdust from the environment may be a health hazard at certain levels. The amount of heavy metals in Eucalyptus and Pinus sawdust was evaluated on samples from Kitwe and Ndola to establish if the use of sawdust for energy and surface amendments was safe. Composite samples for each wood type were collected from each site and digested. The ensuing solution was filtered and analyzed by flame emission Atomic Absorption Spectroscopy for heavy metals. Smoke from a burning test was trapped on Whateman 41 filter paper and the particulate matter that was trapped was extracted. The extract mixture was centrifuged to obtain a clear solution which was then analyzed for heavy metals by AAS. The heavy metal concentrations in Eucalyptus sawdust were 11,5-61,1 mg Pb/kg; 3,3-7,9 mg Cd/kg; 4,9-56,9 mg Cr/kg and 20,2-43,4 mg Ni/kg while that in Pinus sawdust were 17,1-32,8 mg Pb/kg; 5,1-8,6 mg Cd/kg; 9,9-28,2 mg Cr/kg and 18,7-67,4 mg Ni/kg. The concentrations of chromium and cadmium in both wood types from Kitwe exceeded the limit, and so the sawdust was deemed unsuitable for surface applications. This was the same for nickel in Pinus sawdust. The study showed that sawdust from both wood types was not safe for mulching, composting and animal bedding. The annual exposure limits of 0,2 μg Cr/m3, 180 μg Ni/m3 and 0,2 μg Cd/m3 set by the World Health Organization were not exceeded by the smoke from both wood types. This suggested that heavy metals embedded on particulate matter from Eucalyptus and Pinus sawdust which has been in storage for about two years in conditions found in Kitwe is unlikely to have adverse short-term health effects associated with heavy metals.

Accurate prediction of genetic potential and response to selection in breeding requires knowledge of genetic parameters for important selection traits. In this study, we estimated genetic parameters for wood properties in Khasi pine (Pinus kesiya Royle ex Gordon) grown in Malawi. Data on wood properties and growth traits were collected from six families of Pinus kesiya at the age of 30. The results show that wood density had a higher genetic control (h2 = 0.595 ± 0.055) than wood stiffness (h2 = 0.559 ± 0.038) and wood strength (h2 = 0.542 ± 0.091). The genetic correlation among wood quality traits was significantly moderate (0.464 ± 0.061) to high (0.735 ± 0.025). The predicted genetic response indicated that selection for wood density at 10% selection intensity would increase stiffness and strength by 12.6% and 8.85%, respectively. The genetic correlations between growth and wood quality traits were moderately unfavourable. However, sufficient variation exists within the breeding population to select individuals with both good growth rate and high wood quality traits. It is therefore suggested that all trees with both diameter at breast height (DBH) greater than 32.0 cm and density greater than 0.593 g/cm3 must be selected in order to increase the efficiency of the breeding programme. However, in the long term, it is recommended that the best selection strategy would be to develop a multiple-trait selection index. The selection index should be developed using optimal index weights for the advanced Pinus kesiya breeding programme in Malawi. [ABSTRACT FROM AUTHOR]

Key message : Growth ring study of Pinus kesiya (khasi pine) growing in sub-tropical forest in Manipur, northeast India was performed to understand climate signatures in ring widths and intra-annual density fluctuations. Abstract: The growth rings in khasi pine ( Pinus kesiya Royle ex Gordon) growing in sub-tropical Reserve Forest in Imphal, Manipur, northeast India were analysed to understand environmental signals present in ring-width series and intra-annual density fluctuations (IADFs). For this the growth ring sequences in increment core samples collected from 28 trees were precisely dated and a ring-width chronology spanning AD 1958-2014 developed. The correlation analyses between ring-width chronology and weather data of Imphal revealed that a cool April-May-June favour tree growth. The wood anatomical features of growth rings revealed the occurrence of IADFs in early- and latewoods. The IADFs in earlywood were found to be associated with reduced precipitation in months from April to July. However, the wetter conditions in late growing season, especially August/September triggered the formation of IADFs in latewood. Our findings endorse that the IADF chronologies of khasi pine could emerge as an important proxy of summer monsoon rainfall in long-term perspective in data scarce region of northeast India. [ABSTRACT FROM AUTHOR]

Mosquitoes (Diptera: Culicidae) are vectors of important parasites and pathogens causing death, poverty and social disability worldwide, with special reference to tropical and subtropical countries. The overuse of synthetic insecticides to control mosquito vectors lead to resistance, adverse environmental effects and high operational costs. Therefore, the development of eco-friendly control tools is an important public health challenge. In this study, the mosquito larvicidal activity of Pinus kesiya leaf essential oil (EO) was evaluated against the malaria vector Anopheles stephensi, the dengue vector Aedes aegypti and the lymphatic filariasis vector Culex quinquefasciatus . The chemical composition of the EO was analyzed by gas chromatography–mass spectroscopy. GC–MS revealed that the P. kesiya EO contained 18 compounds. Major constituents were α-pinene, β-pinene, myrcene and germacrene D. In acute toxicity assays, the EO showed significant toxicity against early third-stage larvae of An. stephensi, Ae. aegypti and Cx. quinquefasciatus, with LC 50 values of 52, 57, and 62 µg/ml, respectively. Notably, the EO was safer towards several aquatic non-target organisms Anisops bouvieri, Diplonychus indicus and Gambusia affinis , with LC 50 values ranging from 4135 to 8390 µg/ml. Overall, this research adds basic knowledge to develop newer and safer natural larvicides from Pinaceae plants against malaria, dengue and filariasis mosquito vectors. [ABSTRACT FROM AUTHOR]

Successful development of an appropriate tree breeding strategy and wood utilization requires information on wood properties. This study was therefore conducted to assess wood density and mechanical properties of Pinus kesiya Royle ex Gordon grown in Malawi. Wood samples from six families of P. kesiya at the age of 30 years were used for the study. The estimated mean wood density, Modulus of Elasticity (MoE), Modulus of Rupture (MoR) and moisture content were 0.593 ± 0.001 g/cm3, 13.46 ± 0.07 GPa, 113.67 ± 0.57 MPa and 12.08% ± 0.03%, respectively. There were statistically significant (p < 0.001) differences in wood density and mechanical properties along the radial direction and stem height. Wood density and mechanical properties increased from pith to bark and decreased from the butt upwards. There were no significant (p > 0.05) differences in wood density and mechanical properties among the families. This is an indication that any tree among the families can be selected for tree improvement programs if density is considered as a variable. Wood density had a strong positive significant linear relationship with both MoE (r = 0.790; p < 0.001) and MoR (r = 0.793; p < 0.001). This suggests that it has the potential to simultaneously improve the wood density and mechanical properties of this species. Therefore, controlling wood density for the tree improvement program of P. kesiya in Malawi would have a positive impact on mechanical properties. [ABSTRACT FROM AUTHOR]

In this study, microwave plasma was used to treat the surface of Pinus yunnanensis wood under the conditions of 220 V of input voltage, 20 μA of filament current, 8.8 mW of output power, 11 mW of reflected power, 2450 MHz of frequency, and 700 Pa of vacuum. The microwave plasma presented very significant treatment effects on the treated surface, even under weak treatment conditions, for example long treatment distance of 120 mm and short treatment time of 60 s. The treated surface showed better surface wettability, and the contact angles on the treated surface measured from deionized water, glycerin, and diiodomethane decreased sharply, even decreased to 0°. The treated surface also presented higher surface free energy, for example, 61.4-62.8 mJ m, being greatly improved by microwave plasma compared to that of untreated surface of 46.5 mJ m. The bond strength of the treated surface was 7.34 MPa, about 16 % higher than 6.31 MPa for untreated surface. The best treatment effect was obtained for the treatment distance of 120 mm and treatment time of 60-300 s. This technique might be widely used in wood modification and wood processing. [ABSTRACT FROM AUTHOR]

The study was undertaken to evaluate form factors forPinus kesiyagrowing in the three Zambia Forest and Forestry Industries Corporation (ZAFFICO) plantations – the Ndola, Ichimpe and Chati groups – under different rainfall (900–1 500 mm) and soil conditions (pH 4.0–5.5). Trees were sampled from the three plantation groups and 10 sample plots were established in which 10 trees were randomly sampled for cutting. Height and diameter at breast height (dbh) were the main variables that were measured and constituted the collected data. The trees were then felled and cut into segments of 0.5 m from the bottom to the top of the tree and segment diameters over bark were measured at both ends. The form factor for each tree was then calculated by dividing the sum of the volume of the tree segments by the estimated cylindrical volume of the standing tree. The results showed significant differences (p-value<0.05) in form factors among the three plantation groups. The study further showed a significant difference in form factor when the three plantation groups were compared with a fixed form factor (0.4) used by ZAFFICO plantations, indicating that the form factors are site specific. Therefore, for the benefit of customers and plantation owners, it is important that area-specific form factors should be used for each plantation group, as these groups are affected by different factors such as soils characteristics and rainfall, which have a direct effect on the form factor. [ABSTRACT FROM PUBLISHER]

Bursaphelenchus kesiyae n. sp. is described. The new species was isolated from dead wood of Pinus kesiya during a field survey of nematodes associated with dead pine trees (Pinus spp.). The new species is medium- to large-sized for the genus, with males 690-1059 pm and females 837-1122 pm in body length, and has four lateral lines, six male genital papillae (PI ventral single papilla is missing or vestigial), a mitten-shaped spicule with clear dorsal and ventral limbs, an indistinctive small and narrow bursal flap, vulva lacking any flap apparatus, and female tail long, tapering and straight or slightly ventrally curved. Based upon its diagnostic morphological characters, the new species belongs to the B. fungivorus group and is closely related to B. thailandae and B. parathailandae, with which it forms a cryptic species complex. However, the new species is distinguished from these two species by the morphology of the male bursal flap and several morphometric values, i.e., the bursal flap of the new species is inconspicuous, or almost lost in many individuals. Molecular phylogenetic analysis inferred from near-full-length SSU and D2-D3 LSU supported the morphological observations, i.e., the new species is molecularly similar to B. thailandae and B. parathailandae, but could be distinguished phylogenetically. Further, differences in molecular sequences in SSU and D2-D3 LSU between the new species and its close relatives are slightly higher than those between B. xylophilus and B. mucronatus, thus, identification of the species status for B. kesiyae n. sp. is considered warranted. [ABSTRACT FROM AUTHOR]

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