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Plasticity of mycangia in Xylosandrus ambrosia beetles

Insect Science 2019年第4期26卷 732-742页

作者： You Li Yong-Ying Ruan Edward L. Stanley James Skelton Jiri Hulcr School of forest Resources and Conservation University of Florida Gainesville Florida USA School of Applied Chemistry and Biological Technology Postdoctoral Innovation Practice Base Shenzhen Polytechnic Shenzhen. Guangdong. China Florida Museum of Natural History University of Florida Gainesville Florida USA Entomology and Nematology Department University of Florida Gainesville Florida USA

Insects that depend on microbial mutualists evolved a variety of organs to transport the microsymbionts while dispersing. The ontogeny and variability of such organs is rarely studied, and the microsymbiont*s effects on the animal tissue development remain unknown in most cases. Ambrosia beetles (Coleoptera: Curculionidae: Scolytinae or Platypodinae) and their mutualistic fungi are an ideal system to study the animalfungus interactions. While the interspecific diversity of their fungus transport organ一 mycangia—is well-known, their developmental plasticity has been poorly described. To determine the ontogeny of the mycangium and the influence of the symbiotic fungus on the tissue development, we dissected by hand or scanned with micro-CT the mycangia in various developmental stages in five Xylosandrus ambrosia beetle species that possess a large, mesonotal mycangium: Xylosandrus amputatus. Xylosandrus compactus, Xylosandrus crassiusculus, Xylosandrus discolor, and Xylosandrus germanus. We processed 181 beetle samples from the united states and China. All five species displayed three stages of the mycangium development:(1) young teneral adults had an empty, deflated and cryptic mycangium without fungal mass;(2) in fully mature adults during dispersal, the promesonotal membrane was inflated, and most individuals developed a mycangium mostly filled with the symbiont, though size and symmetry varied;and (3) after successful establishment of their new galleries, most females discharged the bulk of the fun gal inoculum and deflated the mycangium. Experimental aposymbiotic individuals demonstrated that the pronotal membrane invaginated independently of the presence of the fungus, but the fungus was required for inflation. Mycangia are more dynamic than previously thought, and their morphological changes correspond to the phases of the symbiosis. Importantly, studies of the fungal symbionts or plant pathogen transmission in ambrosia beetles need to consider which developmen

关键词： callow micro-CT mycangium symbiont-induced symbiosis teneral

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Fitness and physiology of Adelges tsugae （Hemiptera： Adelgidae） in relation to the health of the eastern hemlock

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Insect Science 2016年第6期23卷 843-853页

作者： Anne C. Jones Donald E. Mullins Carlyle Brewster James P. Rhea Scott M. Salom Department of Entomology Pennsylvania State University PA 16801 Department of Entomology Virginia Tech Blacksburg VA 24061 USDA forest service Asheville NC 28804-3454 USA

The hemlock woolly adelgid, Adelges tsugae Annand is an invasive insect that frequently causes hemlock （Tsuga spp.） mortality in the eastern united states. Studies have shown that once healthy hemlocks become infested by the adelgid, nutrients are depleted from the tree, leading to both tree decline and a reduction of the adelgid population. Since A. tsugae is dependent on hemlock for nutrients, feeding on trees in poor health may affect the ability of the insect to obtain necessary nutrients and may consequently affect their physiological and population health. Trees were categorized as lightly or moderately impacted by A. tsugae based on quantitative and qualitative tree health measurements. Population health ofA. tsugae on each tree was determined by measuring insect density and peak mean fecundity; A. tsugae physiological health was determined by measuring insect biomass, total carbon, carbohydrate, total nitrogen, and amino nitrogen levels. Adelges tsugae from moderately impacted trees exhibited significantly greater fecundity than from lightly impacted trees. However, A. tsugae from lightly impacted hemlocks contained significantly greater levels of carbohydrates, total nitrogen, and amino nitrogen. While the results of the physiological analysis generally support our hypothesis that A. tsugae on lightly impacted trees are healthier than those on moderately impacted trees, this was not reflected in the population health measurements. Adelges tsugae egg health in response to tree health should be verified. This study provides the first examination of A. tsugae physiological health in relation to standard A. tsugae population health measures on hemlocks of different health levels.

关键词： Adelges tsugae carbohydrates fecundity nitrogen tree health Tsuga canadensis

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Comparative morphometric and chemical analyses of phenotypes of two invasive ambrosia beetles （Euwallacea spp.） in the united states

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Insect Science 2017年第4期24卷 647-662页

作者： Yigen Chen Paul L. Dallara Lori J. Nelson Tom W. Coleman Stacy M. Hishinuma Daniel Carrillo Steven J. Seybold Department of Entomology and Nematology University of California Davis USA USDA forest service Pacific Southwest Research Station Davis USDA forest service Forest Health Protection San Bemardino California USA Tropical Research and Education Center University of Florida Homestead Florida USA

The polyphagous shot hole borer （PSHB）, Euwallacea sp., was first detected in 2003 in Los Angeles County, California, USA. Recently, this invasive species has become a major pest of many hardwood trees in urban and wildland forests throughout southern California. PSHB is nearly identical in morphology and life history to the tea shot hole borer （TSHB）, Euwallaceafornicatus, an invasive pest of hardwoods in Florida, USA and many other parts of the world. However, molecular studies have suggested that the taxa are different species. We conducted morphometric and chemical analyses of the pheno- types of Euwallacea sp. collected in southern California （Los Angeles County） and E. fornicatus collected in Florida （Miami-Dade County）. Our analyses indicated that PSHB has 3 larval instars. The third larval instar was separated from the first 2 instars by head capsule width with 0 probability of misclassification. The body length, head width, and pronotal width of PSHB adult males were significantly less than those of females. Head width and pronotal width of female PSHB were significantly less than those of female TSHB. In contrast, body length, and ratio of body length to pronotal width of female PSHB were significantly greater than those of female TSHB. However, females of these 2 species could not be separated completely by these 4 measurements because of the overlapping ranges. Cuticular hydrocarbons detected in both species were exclusively alkanes （i.e., n-alkanes, monomethylalkanes, dimethylalkanes, and trimethylalkanes）. Cuticular hydro- carbon profiles of PSHB males and females were similar, but they both differed from that of TSHB females. Cuticular hydrocarbons of PSHB were predominantly internally branched dimethylalkanes with backbones of 31 and 33 carbons, whereas cuticular hydro- carbons of TSHB females were dominated by internally branched monomethylalkanes and dimethylalkanes with backbones of 28 and 29 carbons. Multiple compounds within these classes appear

关键词： cuticular hydrocarbons Euwallaceafornicatus larval instars polyphagousshot hole borer Scolytidae tea shot hole borer

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Vegetation Geo-climatic Zonation in the Rocky Mountains, Northern Utah, USA

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Journal of Mountain Science 2014年第3期11卷 656-673页

作者： Antonin KUSBACH Helga VAN MIEGROET Janis L.BOETTINGER James N.LONG Department of Wildland Resources and Ecology Center Utah State University Utah State University Department of forest Botany Dendrology and Geobiocoenology Mendel University in Brno

We developed a vegetation geo-climatic zonation incorporating the zonal concept, gradient and discriminant analysis in Wasatch Range, northern Utah, USA. Mountainous forest ecosystems were sampled and described by vegetation, physiographic features and soil properties. The Snowpack Telemetry and National Weather service Cooperative Observer Program weather station networks were used to approximate the climate of sample plots. We analysed vegetation and environmental data using clustering, ordination, classification, and ANOVA techniques to reveal environmental gradients affecting a broad vegetation pattern and discriminate these gradients. The specific objective was to assess and classify the response of the complex vegetation to those environmental factors operating at a coarse-scale climatic level. Ordination revealed the dominant role of regional, altitude-based climate in the area. Based on vegetation physiognomy, represented by five tree species, climatic data and taxonomic classification of zonal soils, we identified two vegetation geo-climatic zones:(1) a montane zone, with Rocky Mountain juniper and Douglas-fir; and(2) a subalpine zone, with Engelmann spruce and subalpine fir as climatic climax species. Aspen was excluded from the zonation due to its great ecological amplitude. We found significant differences between the zones in regional climate and landformgeomorphology/soils. Regional climate was represented by elevation, precipitation, and air and soil temperatures; and geomorphology by soil types. This coarse-scale vegetation geo-climatic zonation provides a framework for a comprehensive ecosystem survey, which is missing in the central Rocky Mountains of the united states. The vegetation-geoclimatic zonation represents a conceptual improvement on earlier classifications. This framework explicitly accounts for the influence of the physical environment on the distribution of vegetation within a complex landscape typical of the central Rocky Mountains an

关键词： Ecological classification Ecosystemsurvey Land classification Zonal concept Vegetation zone Vegetation geo-dimatic zone Climate change

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Assessment of coastal and mangrove vulnerability in the Andaman Island,Indian Ocean

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Geoscience Frontiers 2024年第5期15卷 47-60页

作者： Biswajit Mondal Rupesh K.Bhomia Ashis Kumar Saha Richard A.MacKenzie Department of Geography Delhi School of EconomicsUniversity of DelhiDelhi 110007India Centre for International forestry Research(CIFOR) Jalan CIFORSitu GedeBogor BaratBogor 16115Indonesia Institute of Pacific Islands forestry Pacific Southwest Research StationUSDA Forest ServiceHiloHI 96720USA

Coastal regions are highly susceptible to the effects of global warming,including rising atmospheric and sea surface temperatures,increased cyclone frequency,and sea level ***,it is imperative to examine coastal vulnerability to minimize the impact of multiple hazards and protect coastal resources,such as *** in India studying the vulnerability of coastal zones of Andaman and Nicobar Islands which fall in seismic zone V is critical for conservation *** conducted a vulnerability analysis of coastal zones impacted by the 2004 earthquake,causing varying degrees of ground upliftment and *** compared coastal vulnerability among sites that experienced uplift,no change,and subsidence(the southern portion).Our analysis utilized the Coastal and Mangrove Vulnerability Index(CVI and MVI)to measure and compare vulnerability in six zones distributed along uplift and subsidence ***-resolution satellite imagery including WorldView-2,3,and GeoEye-1 from year 2022 are utilized on this *** CVI and MVI offers a good way to measure and compare vulnerabilities across sites and offer insights for better *** CVI and MVI results indicate that approximately 34%of coastal grids and over 23%of mangrove grids across all zones are highly to extremely highly *** zones were found to be more vulnerable than uplifted *** findings suggest that large-scale natural disturbances such as tectonic displacement have the potential to impact coastal vegetation and mangrove cover can become even more *** conclusion,our study emphasizes the importance of vulnerability analyses in coastal regions,especially in areas prone to seismic *** findings have direct implications for conservation and restoration efforts and underscore the need for continued monitoring and mitigation efforts to safeguard coastal resources for long-term sustainability.

关键词： Mangroves Coastal vulnerability Mangrove vulnerability 2004 Indian Ocean earthquake Andaman Island

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Two decades of compositional and structural change in deciduous old-growth forests of Indiana,USA

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Journal of Plant Ecology 2016年第3期9卷 256-271页

作者： Christy A.Lowney Bradley D.Graham Martin A.Spetich Stephen R.Shifley Michael R.Saunders Michael A.Jenkins Department of forestry and Natural Resources and Hardwood Tree Improvement and Regeneration Center Purdue University715 West State StreetWest Lafayette IN 47907USA Arkansas forestry Sciences Laboratory USDA Forest ServiceSouthern Research StationP.O.Box 1270Hot SpringsAR 71902USA USDA forest service Northern Research Station202 ABNR BuildingColumbiaMO 65201USA

Aims Using a network of permanent plots,we determined how multiple old-growth forests changed over an 18-19-year period at a state-wide *** examination of change allowed us to assess how the compositional and structural stability of each forest varied with site characteristics(topography,physiography and productivity)and stochastic *** In 2011,we resampled 150 plots distributed across five old-growth hardwood forests in Indiana,USA that were originally sampled in *** each plot,we relocated and remeasured the diameter at breast height(dbh)of all trees(≥10.0 cm)present during the 1992-1993 sample,which allowed us to track their individual fates through time for growth and mortality *** that grew to≥10.0 cm dbh since plot establishment were designated as *** dbh and species of all saplings(stems≥2.0 cm butforest,we calculated density(stems ha^(−1)),basal area(BABA;m^(2)ha^(−1))and importance value(relative density+relative BABA)/2 of trees by *** saplings,density per ha was calculated by species for each *** also calculated annual mortality rate(AMR)for three diameter classes(10-29.9,30-59.9 and≥60 cm)and species richness(S),evenness(E)and Shannon-Weiner diversity(H')for the tree and sapling *** between years were compared for each forest using paired t-tests and Wilcoxon signed rank *** FindingsAlthough we observed commonality in changes across some sites,our results suggest that these forests differ in their rates and trajectories of *** in total stand BABA and density varied across sites and were influenced by past disturbance and mortality *** observed a general increase in the overstory dominance of Acer saccharum coupled with a general decrease in the dominance of Quercus section Lobatae(red oak group)*** of overstory trees present in 1992-1993 ranged from 27%to 49%over the study period(mean AM

关键词： forest remnants forest structure long-term data mortality species diversity stand development.

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Measuring tree stem diameters and straightness with depth-image computer vision

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Journal of forestry Research 2023年第5期34卷 1395-1405页

作者： Hoang Tran Keith Woeste Bowen Li Akshat Verma Guofan Shao Department of Computer Science Purdue University305 N University StWest LafayetteIN 47907USA Hardwood Tree Improvement and Regeneration Center USDA Forest ServiceNorthern Research Station715 West State StreetWest LafayetteIN 47907USA Department of forestry and Natural Resources Purdue University715 West State StreetWest LafayetteIN 47907USA School of Electrical and Computer Engineering Purdue University610 Purdue MallWest LafayetteIN 47907USA

Current techniques of forest inventory rely on manual measurements and are slow and labor *** developments in computer vision and depth sensing can produce accurate measurement data at significantly reduced time and labor *** developed the ForSense system to measure the diameters of trees at various points along the stem as well as stem *** use,mean absolute error(MAE),and root mean squared error(RMSE)metrics were used to compare the system against manual methods,and to compare the system against itself(reproducibility).Depth-derived diameter measurements of the stems at the heights of 0.3,1.4,and 2.7 m achieved RMSE of 1.7,1.5,and 2.7 cm,*** ForSense system produced straightness measurement data that was highly correlated with straightness ratings by trained *** ForSense system was also consistent,achieving sub-centimeter diameter difference with subsequent measures and less than 4%difference in straightness value between *** method of forest inventory,which is based on depth-image computer vision,is time efficient compared to manual methods and less computationally and technologically intensive compared to Structure-from-Motion(SFM)photogrammetry and ground-based LiDAR or terrestrial laser scanning(TLS).

关键词： forest inventory Depth sensing Computer vision Tree diameter Stem straightness Trunk volume

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Machine learning-based spectral and spatial analysis of hyper-and multi-spectral leaf images for Dutch elm disease detection and resistance screening

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Artificial Intelligence in Agriculture 2023年第4期10卷 26-34页

作者： Xing Wei Jinnuo Zhang Anna O.Conrad Charles E.Flower Cornelia C.Pinchot Nancy Hayes-Plazolles Ziling Chen Zhihang Song Songlin Fei Jian Jin Department of Agricultural and Biological Engineering Purdue UniversityWest LafayetteIN 47907United States USDA forest service Northern Research StationHardwood Tree Improvement and Regeneration CenterWest LafayetteIN 47906United States USDA forest service Northern Research StationDelawareOH 43015United States Department of forestry and Natural Resources Purdue UniversityWest LafayetteIN 47907United States

Diseases caused by invasive pathogens are an increasing threat to forest health,and early and accurate disease detection is essential for timely and precision forest *** recent technological advancements in spectral imaging and artificial intelligence have opened up new possibilities for plant disease detection in both crops and *** this study,Dutch elm disease(DED;caused by Ophiostoma novo-ulmi,)and American elm(Ulmus americana)was used as example pathosystem to evaluate the accuracy of two in-house developed high-precision portable hyper-and multi-spectral leaf imagers combined with machine learning as new tools for forest disease ***-and multi-spectral images were collected from leaves of American elm geno-types with varied disease susceptibilities after mock-inoculation and inoculation with ***-ulmi under green-house *** traditional machine learning and state-of-art deep learning models were built upon derived spectra and directly upon spectral image *** learning models that incorporate both spectral and spatial features of high-resolution spectral leaf images have better performance than traditional machine learning models built upon spectral features alone in detecting *** and symptomatic spots on the leaves were highlighted in the deep learning model as important spatial features to distinguish leaves from inoculated and mock-inoculated *** addition,spectral and spatial feature patterns identified in the machine learning-based models were found relative to the DED susceptibility of elm *** further studies are needed to assess applications in other pathosystems,hyper-and multi-spectral leaf imagers combined with machine learning show potential as new tools for disease phenotyping in trees.

关键词： American elm Dutch elm disease Hyperspectral imaging Multispectral imaging Support vector machine Convolution neural network Disease phenotyping Digital forestry

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Application of remote sensing,an artificial neural network leaf area model,and a process-based simulation model to estimate carbon storage in Florida slash pine plantations.

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Journal of forestry Research 2010年第2期21卷 171-176,I0005页

作者： Douglas A.Shoemaker Wendell P.Cropper Jr The Center for Applied Geographical Information Science McEniry 320University of North Carolina-Charlotte9201 University City Blvd.Charlotte School of forest Resources and Conservation Box 110410University of Florida

Carbon sequestration in forests is of great interest due to concerns about global climate *** storage rates depend on ecosystem fluxes（photosynthesis and ecosystem respiration）,typically quantified as net ecosystem exchange（NEE）.Methods to estimate forest NEE without intensive site sampling are needed to accurately assess rates of carbon sequestration at stand-level and larger *** produced spatially-explicit estimates of NEE for 9 770 ha of slash pine（Pinus elliottii） plantations in North-Central Florida for a single year by coupling remote sensing-based estimates of leaf area index（LAI） with a process-based growth simulation *** estimates produced from a neural-network modeling of ground plot and Landsat TM satellite data had a mean of 1.06（range 0-3.93,including forest edges）.Using the neural network LAI values as inputs,the slash pine simulation model（SPM2） estimates of NEE ranged from-5.52 to 11.06 Mg·ha^-1·a^-1with a mean of 3.47 Mg·ha^-1·a^-1Total carbon storage for the year was 33920 t,or about 3.5 tons per *** estimated LAI and NEE were highly sensitive to fertilization.

关键词： artificial neural network leaf area carbon exchange slash pine NEE forest carbon

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An approximate point-based alternative for the estimation of variance under big BAF sampling

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forest Ecosystems 2021年第3期8卷 439-457页

作者： Thomas B.Lynch Jeffrey H.Gove Timothy G.Gregoire Mark J.Ducey Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater 74078OKUSA USDA forest service Northern Research Station271 Mast RoadDurham 03824NHUSA Yale School of Environment Yale University360 Prospect StNew Haven 06511CTUSA Department of Natural Resources and the Environment University of New Hampshire114 James HallDurham 03824NHUSA

Background:A new variance estimator is derived and tested for big BAF(Basal Area Factor)sampling which is a forest inventory system that utilizes Bitterlich sampling(point sampling)with two BAF sizes,a small BAF for tree counts and a larger BAF on which tree measurements are made usually including DBHs and heights needed for volume ***:The new estimator is derived using the Delta method from an existing formulation of the big BAF estimator as consisting of three sample *** new formula is compared to existing big BAF estimators including a popular estimator based on Bruce’s ***:Several computer simulation studies were conducted comparing the new variance estimator to all known variance estimators for big BAF currently in the forest inventory *** simulations the new estimator performed well and comparably to existing variance ***:A possible advantage of the new estimator is that it does not require the assumption of negligible correlation between basal area counts on the small BAF factor and volume-basal area ratios based on the large BAF factor selection trees,an assumption required by all previous big BAF variance estimation *** this correlation was negligible on the simulation stands used in this study,it is conceivable that the correlation could be significant in some forest types,such as those in which the DBH-height relationship can be affected substantially by density perhaps through *** derived a formula that can be used to estimate the covariance between estimates of mean basal area and the ratio of estimates of mean volume and mean basal *** also mathematically derived expressions for bias in the big BAF estimator that can be used to show the bias approaches zero in large samples on the order of 1n where n is the number of sample points.

关键词： Bitterlich sampling Delta method Double sampling Estimator bias forest inventory Horizontal point sampling Variance of a product Volume basal area ratio Covariance estimation

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