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2022 ◽  
Vol 147 (1) ◽  
pp. 62-69
Author(s):  
Phillip A. Wadl ◽  
Timothy A. Rinehart ◽  
Richard T. Olsen ◽  
Benjamin D. Waldo ◽  
Joseph H. Kirkbride

The genus Chionanthus, known as fringetrees, is a member of the olive family (Oleaceae). Chionanthus virginicus is an understory tree or shrub with a wide range in forests of the eastern United States and is used as an ornamental tree that is known to be free of insects and disease in the wild. The species is tolerant of a wide range of environmental conditions, and there is interest in developing new cultivars with improved horticultural traits, such as tree form or upright growth habit and superior flowering display that are widely adapted. To identify genepools in the native range of C. virginicus for use in breeding programs, the genetic diversity and population structure were assessed for 274 individuals from 12 locations in four states (Florida, Maryland, North Carolina, and Texas) using 26 simple sequence repeats (SSRs). An average of 12.54 alleles/locus were detected, allelic richness averaged 2.80. Genetic differentiation was 0.11, indicating moderate differentiation among subpopulations. Despite the high genetic diversity and low population differentiation, Bayesian clustering analysis identified six genetic groups that match the geographic distribution of collection sites. Analysis of molecular variance indicated that most (82%) of the variation is explained within individuals, and 11% and 7% of the variation is due to differences among individuals within populations and among populations. Analysis of isolation by distance across all samples showed a weak positive relationship between geographic distance and genetic distance. The C. virginicus samples analyzed in this study indicate there is sufficient diversity for germplasm collection for use in breeding programs. Given the relatively moderate genetic differentiation, there are not likely to be unique islands of genetic diversity that may be missed when gathering parental materials for a breeding program


2021 ◽  
Vol 12 (1) ◽  
pp. 60
Author(s):  
Samuel Ndichu ◽  
Sangwook Kim ◽  
Seiichi Ozawa ◽  
Tao Ban ◽  
Takeshi Takahashi ◽  
...  

Attacks using Uniform Resource Locators (URLs) and their JavaScript (JS) code content to perpetrate malicious activities on the Internet are rampant and continuously evolving. Methods such as blocklisting, client honeypots, domain reputation inspection, and heuristic and signature-based systems are used to detect these malicious activities. Recently, machine learning approaches have been proposed; however, challenges still exist. First, blocklist systems are easily evaded by new URLs and JS code content, obfuscation, fast-flux, cloaking, and URL shortening. Second, heuristic and signature-based systems do not generalize well to zero-day attacks. Third, the Domain Name System allows cybercriminals to easily migrate their malicious servers to hide their Internet protocol addresses behind domain names. Finally, crafting fully representative features is challenging, even for domain experts. This study proposes a feature selection and classification approach for malicious JS code content using Shapley additive explanations and tree ensemble methods. The JS code features are obtained from the Abstract Syntax Tree form of the JS code, sample JS attack codes, and association rule mining. The malicious and benign JS code datasets obtained from Hynek Petrak and the Majestic Million Service were used for performance evaluation. We compared the performance of the proposed method to those of other feature selection methods in the task of malicious JS code content detection. With a recall of 0.9989, our experimental results show that the proposed approach is a better prediction model.


2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Mirzeta Memišević Hodžić ◽  
Dalibor Ballian

Provenance tests of forest tree species are important experiments in silviculture and tree breeding. Their results provide information about provenances' growth, adaptability, and other features. The research aimed to determine the dynamics of growth and tree shape of common beech plants per provenances in the international provenance test in Bosnia and Herzegovina to choose the best provenances considering wood production and quality. Research was conducted in the provenance test containing eight provenances from Bosnia and Herzegovina, four from Germany, three from Serbia, two each from Croatia, Romania, and Switzerland, and one from Hungary. Provenance test was established in 2007 by planting 2-year-old and 3-year old seedlings. Height and root collar diameter were measured, and tree shape was assessed in 2019. Data were processed in SPSS 26.0. Descriptive statistics, variance analysis, multiple Duncan's test for all traits, and Pearson's coefficient of corelation among morphological traits and tree shape were calculated. Variance for the height and root collar diameter showed statistically significant differences among different ages of plants and among provenances. Provenance from Croatia (Dilj Čaglinski) had the highest, and provenance from Romania (Alba-Iulia) had the lowest average height. The highest average value of root collar diameter had provenance Dilj Čaglinski, and the lowest value had provenance Sihlwald (Switzerland). The highest percentage of category 10 (ideal tree form) had provenance Bad Wildbad (Germany), and categories 1-4 (no silviculture value) had provenance Alba-Iulia (Romania). Pearson's coefficient showed that height, root collar diameter, and tree shape are highly correlated. Considering all the above, when planning forest-breeding works, it is recommended to continue the research and favor provenances with the best growth and tree shape.


2021 ◽  
Vol 918 (1) ◽  
pp. 012015
Author(s):  
L Karlinasari ◽  
U Adzkia ◽  
Y Fredisa ◽  
M M Rahman ◽  
N Nugroho ◽  
...  

Abstract Tree growth comprises diverse tree forms and crown shapes that are influenced by the growing space and are related to biomechanical responses. Due to the complex structures of tree forms and crown architecture, more understanding of their functions is necessary. The study aimed to evaluate the morphometrics of two tree species of contrasting tree forms. Each represents excurrent and decurrent crown architectures located in the Dramaga Campus Landscape, Bogor. Morphometric analysis was conducted on those two species, namely excurrent agathis (n=23 trees) and decurrent mangium (n= 15 trees). The morphometric analysis was carried out for several basic growth variables such as diameter at breast height, total height, and crown height. In addition, other variables and parameters were also assessed, namely live crown ratio, slenderness ratio, crown diameter, crown projection area, crown index, and coefficient of space for growth. The results showed that the average diameters of agathis and mangium trees in this study were 0.49 and 0.48 m, respectively, while the average heights were 24.63 m and 18.23 m, respectively. The live crown ratio of both trees was more than 80%. The average slenderness ratio for agathis trees was 50.66 higher than that of mangium trees (40.64). The crown projection areas for agathis and mangium were 37.60 m2 and 69.69 m2, respectively. On the other hand, the crown index of agathis was 3.20, and mangium was 1.84. The coefficient of space for the growth of agathis and mangium was 0.14. and 0.19. The information related to tree morphometry is important for tree management, especially in evaluating healthy and steady tree stands.


Author(s):  
Igor V. Evdokimov ◽  
◽  
Aleksandr P. Dobrynin ◽  
Nelli A. Armeeva ◽  
◽  
...  

Common juniper (Juniperus communis L.) is one of the most widespread undergrowth species in the forests of Russia. It has not only important silvicultural significance but is also widely used in economic activities. Numerous works of Russian and foreign authors are devoted to its study. The article shows the results of geobotanical and forest inventory studies of a unique area of pine plantation in the Kirillovskiy district of the Vologda region. In the second understorey of which tree-form common juniper grows. The stand was classified as high-density (relative fullness – 0.85) and low quality (quality class – V–IV). The total stock of trunk wood on the site is 280 m3/ha, including the stock of juniper wood – 28 m3/ha. The average diameter of juniper trunks is 14 cm, the average height is 11 m and the age is 180 yrs. This is several times higher than its usual parameters in other forests. A significant number of specimens of juniper (50 pcs/ha) are in the stage of drying out or have already died and represent dead wood of different years. The number of small and medium-sized juniper undergrowth is 1.5 ths pcs/ha or 62.5 % of the growing. Undergrowth of European spruce, downy birch and black alder is also found. The existing undergrowth is assessed as promising, but Scots pine undergrowth is missing. The ground cover is dominated by green and sphagnum mosses as well as shrubs of the Ericaceae and Vacciniaceae families. The study of such objects, extremely rare not only in the north of the European part of Russia, but also everywhere, is of great practical importance. It is also important for understanding the biology of the only representative of the Cupressaceae family that naturally grows here. The tree-form juniper in the pine plantation has survived and reached a size not typical for this species due to the inaccessibility of the site, the lack of fires and forest felling. Such forest areas should be identified, protected, and subjected to stationary research. For citation: Evdokimov I.V., Dobrynin A.P., Armeeva N.A. Tree Form of Juniper (Juniperus communis L.) in the Forests of the Vologda Region. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 5, pp. 201–209. DOI: 10.37482/0536-1036-2021-5-201-209


2021 ◽  
pp. 148-154
Author(s):  
Yuni Indah Lestari ◽  
Sarjon Defit ◽  
Y Yuhandri

Online service is a service that uses the help of the internet. This service can solve various types of business without having to meet directly with employees. This can be done quickly and on time. Especially when we are currently experiencing the Covid-19 pandemic, all existing services are carried out online and this is increasingly being done by many parties, because they can maximize in helping people's affairs online. This service makes it easier for the public to register which will be done online during this pandemic. The data that will be processed in this online service from 2019 to 2020 is about data about people who do not understand online services, negative community responses, positive community expectations. The method used in this study is the method with the C4.5 algorithm where this is one of the algorithms that will be used to determine a classification or group of data and will be predictive. The advantage of this algorithm is that it can produce a decision tree which will make it easier to implement and will have an acceptable level of accuracy. The results of this study are able to predict a value or determine the level of community satisfaction in 2021 appropriately. Therefore, this study can be used as a reference to determine the level of satisfaction at the Padang City Population and Civil Registration Office. The method used in this study is the prediction method using the C4.5 algorithm by using as many as 14 attributes. The data used in this study is sourced from data from online questionnaires and stored in the Disdukcapil database which has as many as 50 community data which have been presented in a CSV file. The analysis in this study uses the help of tools in the form of rapid miner software version 5.3,000. The results of this study are that there are 3 rules from the data processing process using the C4.5 algorithm where the rule is the final result of the decision tree form.


2021 ◽  
Vol 51 (3) ◽  
pp. 181-190
Author(s):  
Rafael Gonçalves de OLIVEIRA ◽  
Alex Soares de SOUZA ◽  
Victor Alexandre Hardt Ferreira dos SANTOS ◽  
Roberval Monteiro Bezerra de LIMA ◽  
Marciel José FERREIRA

ABSTRACT Plant spacing is a potential driver of tree form and yield in forest plantations. However, its effects on the productivity of tree plantations in the Amazon are still little known. This study examined the effects of six spacing regimes (3 x 4, 4 x 4, 4 x 5, 5 x 5, 5 x 6, and 6 x 6 m) on the growth and morphometry of a 20-year-old plantation of Bertholletia excelsa. We observed high, spacing-independent survival (> 70%). For timber production purposes, intermediate and two large spacing regimes tended to higher values of yield components, mainly diameter, biomass, and volume, although some did not differ significantly from the smallest spacing. One of the intermediate spacings (5 x 5 m) tended to higher commercial height. Tree crowns tended to be wider and longer in the larger spacings, which indicates the potential of these regimes for fruit production. Tree crowns exceeded the vital growth space in all spacing regimes, which suggests the need for thinning before the age of 20 years in all spacings to reduce intraspecific competition and increase yield. We estimated that a density of 84 remaining trees per hectare would be necessary to reach an average diameter of 40 cm at the age of 20 years. Thus, B. excelsa had high survival in the tested range of spacing regimes, while the intermediate and the largest spacing regimes led to better tree growth and morphometry.


Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1594
Author(s):  
Amy L. Klocko ◽  
Amanda L. Goddard ◽  
Jeremy R. Jacobson ◽  
Anna C. Magnuson ◽  
Steven H. Strauss

The central floral development gene LEAFY (LFY), whose mutation leads to striking changes in flowering and often sterility, is commonly expressed in non-floral structures; however, its role in vegetative development is poorly understood. Sterility associated with suppression of LFY expression is an attractive means for mitigating gene flow by both seeds and pollen in vegetatively propagated forest trees, but the consequences of its suppression for tree form and wood production are unclear. To study the vegetative effects of RNAi suppression of LFY, we created a randomized, multiple-year field study with 30–40 trees (ramets) in each of two sterile gene insertion events, three transgenic control events, and a wild-type control population. We found that floral knock-down phenotypes were stable across years and propagation cycles, but that several leaf morphology and productivity traits were statistically and often substantially different in sterile vs. normal flowering RNAi-LFY trees. Though trees with suppressed LEAFY expression looked visibly normal, they appear to have reduced growth and altered leaf traits. LFY appears to have a significant role in vegetative meristem development, and evaluation of vegetative impacts from LFY suppression would be prudent prior to large-scale use for genetic containment.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Greg S. Goralogia ◽  
Glenn T. Howe ◽  
Amy M. Brunner ◽  
Emily Helliwell ◽  
Michael F. Nagle ◽  
...  

AbstractThe spread of transgenes and exotic germplasm from planted crops into wild or feral species is a difficult problem for public and regulatory acceptance of genetically engineered plants, particularly for wind-pollinated trees such as poplar. We report that overexpression of a poplar homolog of the floral repressor SHORT VEGETATIVE PHASE-LIKE (SVL), a homolog of the Arabidopsis MADS-box repressor SHORT VEGETATIVE PHASE (SVP), delayed the onset of flowering several years in three genotypes of field-grown transgenic poplars. Higher expression of SVL correlated with a delay in flowering onset and lower floral abundance, and did not cause morphologically obvious or statistically significant effects on leaf characteristics, tree form, or stem volume. Overexpression effects on reproductive and vegetative phenology in spring was modest and genotype-specific. Our results suggest that use of SVL and related floral repressors can be useful tools to enable a high level of containment for vegetatively propagated short-rotation woody energy or pulp crops.


Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 951
Author(s):  
Chunping Xie ◽  
Guowu Zhang ◽  
Chiyung Jim ◽  
Xuefeng Liu ◽  
Peijian Zhang ◽  
...  

Jacaranda mimosifolia is regarded as a prized ornamental tree in the urban landscape with attractive, abundant and long-lasting violet-colored flowers and graceful tree form. It has been widely cultivated in recent years in many Chinese cities. However, the lack of scientific and practical guidance to cultivate the exotic species has brought about planting failures in some areas, incurring substantial economic losses and landscape decline. A comprehensive understanding of the current spatial pattern and climatic conditions of J. mimosifolia in China can inform species choice, planting and management. We collected data on the geographical coordinates of 257 planting cities and acquired additional information from the literature and field surveys. The limiting factors for cultivation were investigated using principal component analysis (PCA) of 19 bioclimatic parameters of the sampled sites. The potentially suitable habitats were predicted by BIOCLIM modeling using eight selected ecological-important climatic parameters. We found that the present cultivated areas were focused in the low-altitude parts of the subtropical zone, mainly covering the provinces of Yunnan, Sichuan, Guangxi, Guangdong and Fujian. The PCA results indicated that temperature was the clinching determinant of the current cultivation patterns, especially annual mean temperature, the minimum temperature of the coldest month and the mean temperature of the warmest quarter. Moisture was a necessary but not critical secondary factor. The predicting model for potential habitats was graded as “excellent” by objective validation measures. The findings can provide science-based evidence to plan the expansion of the biogeographical range of cultivation into hitherto unplanted cities and rationalize urban tree introduction and management practices.


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