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The seasonal distributions of predatory bugs, specifically species of Orius (Hemiptera: Anthocoridae), and the population dynamics of some sucking pests including aphids, leafhoppers, and thrips in crops plants (i.e. winter and summer vegetables, fruit trees and field crops) in Balcalı, Adana Province, Turkey, were investigated during 2019–2020. A total of four Orius species were identified, which are: Orius laevigatus (Fieber), Orius niger (Wolff), Orius albidipennis (Reuter) and Orius vicinus (Ribaut). The most common species was O. laevigatus, constituting 78.36% of the total adult individual insects. Both O. laevigatus and O. niger were relatively more abundant on broad beans, beans and potatoes compared to fruit trees and open field crops, such as cotton, sesame and soybean. Very few Orius individuals were recorded on fruit trees. Those that were recorded were found mostly on apple trees. Orius and thrips individuals were collected mainly from the flowers of the plants, and their population patterns depended on the flowering phenology patterns of the plants. Significant correlations were detected between the population patterns of Orius individuals and thrips populations in winter and summer vegetables, fruit trees and field crops. This may indicate that thrips are the primary prey of Orius individuals throughout the year in agricultural ecosystems with rich plant diversity. [ABSTRACT FROM AUTHOR]

Reasonably formulating the strawberry harvesting sequence can improve the quality of harvested strawberries and reduce strawberry decay. Growth information based on drone image processing can assist the strawberry harvesting, however, it is still a challenge to develop a reliable method for object identification in drone images. This study proposed a deep learning method, including an improved YOLOv8 model and a new image-processing framework, which could accurately and comprehensively identify mature strawberries, immature strawberries, and strawberry flowers in drone images. The improved YOLOv8 model used the shuffle attention block and the VoV–GSCSP block to enhance identification accuracy and detection speed. The environmental stability-based region segmentation was used to extract the strawberry plant area (including fruits, stems, and leaves). Edge extraction and peak detection were used to estimate the number of strawberry plants. Based on the number of strawberry plants and the distribution of mature strawberries, we draw a growth chart of strawberries (reflecting the urgency of picking in different regions). The experiment showed that the improved YOLOv8 model demonstrated an average accuracy of 82.50% in identifying immature strawberries, 87.40% for mature ones, and 82.90% for strawberry flowers in drone images. The model exhibited an average detection speed of 6.2 ms and a model size of 20.1 MB. The proposed new image-processing technique estimated the number of strawberry plants in a total of 100 images. The bias of the error for images captured at a height of 2 m is 1.1200, and the rmse is 1.3565; The bias of the error for the images captured at a height of 3 m is 2.8400, and the rmse is 3.0199. The assessment of picking priorities for various regions of the strawberry field in this study yielded an average accuracy of 80.53%, based on those provided by 10 experts. By capturing images throughout the entire growth cycle, we can calculate the harvest index for different regions. This means farmers can not only obtain overall ripeness information of strawberries in different regions but also adjust agricultural strategies based on the harvest index to improve both the quantity and quality of fruit set on strawberry plants, as well as plan the harvesting sequence for high-quality strawberry yields. [ABSTRACT FROM AUTHOR]

Sorghum seedling transplanting is an essential agricultural activity in Sub-Saharan Africa. However, conventional manual transplanting of sorghum is a time-consuming, labour-intensive, costly activity with a low transplanting rate, uneven plant distribution, and low degree of accuracy. In order to realize rapid and precise sorghum seedlings transplanting, a duckbill-type mechanism has been designed. This mechanism is a five-bar linkage consisting of two crankshafts, two connecting rods, and a duckbillshaped planter to improve the quality of transplanting operations. The study includes kinematic and synthesis analysis through MATLAB software, parts design, and motion analysis using SolidWorks software. After synthesis analysis using a genetic algorithm, the optimal length between the two cranks is 300 mm, the length of the upper crankshaft is 106 mm, the length of the connecting rod I is 169 mm, the length of the connecting rod II is 222 mm, and the length of the lower crankshaft is 67 mm. Furthermore, the speed and acceleration analysis show that the seedlings are planted with zero-speed operation to obtain a high perpendicularity qualification. The results show that the proposed planting mechanism meets the agronomic requirements of transplanted sorghum with a good transplanting rate. [ABSTRACT FROM AUTHOR]

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The data distribution for plant domestication in the various parts of Anatolia is uneven and quite scarce or altogether missing for large tracts of the region. The Southeastern Taurus region and Central Anatolia provide a relatively good Pre-Pottery Neolithic (PPN) archaeobotanical record, which is also the case, to a certain degree, for Central Anatolia. The rest of present-day Turkey, e.g. , the northeast region, Cilicia, the Lake District and major parts of western Anatolia (the Black Sea, Mediterranean coast and Marmara regions) provide mostly Pottery Neolithic (PN) archaeobotanical data. The PN sites in these regions appear to represent Neolithic "pioneer" communities that established new sites based on an agricultural economy, of which none predate the second half of the 8th millennium cal. BC. Evidently, domesticated plants that first appeared in the Southeastern Taurus region ca. 8500 cal. BC spread rapidly to western Syria, Cyprus and Central Anatolia a couple of hundreds of years later (still within the second half of the 9th millennium cal. BC). It took another millennium for domesticates and agriculture to reach western Anatolia. While the growing intensity of Neolithic research throughout Turkey (western Turkey included) in recent years may change the picture, for now, based on the available data, this is the emerging pattern and it deserves thought. Based on evidence from a range of relevant disciplines (geobotany, archaeobotany, agronomy, genetics, archaeology and ethnobotany) we support a "rapid" model for plant domestication in Anatolia (as opposed to the "protracted" model). We reconstruct the diffusion of domesticates and the new economy in Turkey and into Europe via maritime routes and through the inland "Anatolian Corridor." We offer itinerant farming craftsmen ("expert harvesters") as a possible mechanism in the diffusion of agricultural products during the Neolithic. • The "Göbeklitepe Culture" upheavals heralded a new cultural and socio-economic human era. • Domesticated plant agriculture started in the Southeastern Taurus and diffused to Central Anatolia. • The diffusion patterns of NGW and chickpea support a rapid diffusion model. • Expert harvesters may have played a role in the diffusion of Neolithic domesticated plants. • The "Anatolian Corridor": an east–west Neolithic dispersal route within Turkey and into Europe. [ABSTRACT FROM AUTHOR]

The cultural differences caused by rice cultivation between the north and south of China provide a unique perspective to study the local effect on corporate pro-environmental behavior. In this paper, we investigate the relationship between the geographical distribution of agricultural planting and corporate pro-environmental behavior. We manually collected the city-level rice planting data and used A-share listed companies' data from 2010 to 2019 in China and found that rice culture in the external environment in which the company is embedded has a positive association with the corporate reactive pro-environmental behavior, while rice culture in the internal values which CEO provided with is positively related to the corporate proactive pro-environmental behavior. Moreover, we find that environmental policy and migration are two moderators through which rice culture affects corporate pro-environmental behavior. This study not only sheds light on the agricultural drivers behind corporate pro-environmental behavior and extends the theoretical understanding of how cultural differences caused by geographical factors within countries influence corporate decisions but also helps firms, managers, and stakeholders effectively conduct self-reflection, management, and supervision on environmental issues through farming cultural dimensions. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Past land use legacy effects—extinction debts and immigration credits—might be particularly pronounced in regions characterized by complex and dynamic landscape change. The aim of this study was to evaluate how current woody plant species distribution, composition and richness related to historical and present land uses. Location: A smallholder farming landscape in south‐western Ethiopia. Methods: We surveyed woody plants in 72 randomly selected 1‐ha sites in farmland and grouped them into forest specialist, generalist and pioneer species. First, we investigated woody plant composition and distribution using non‐metric multidimensional scaling. Second, we modelled species richness in response to historical and current distance from the forest edge. Third, we examined diameter class distributions of trees in recently converted vs. permanent farmland. Results: Historical distance was a primary driver of woody plant composition and distribution. Generalist and pioneer species richness increased with historical distance. Forest specialists, however, did not respond to historical distance. Only few old individuals of forest specialist species remained in both recently converted and permanent farmlands. Main conclusions: Our findings suggest that any possible extinction debt for forest specialist species in farmland at the landscape scale was rapidly paid off, possibly because farmers cleared large remnant trees. In contrast, we found substantial evidence of immigration credits in farmland for generalist and pioneer species. This suggests that long‐established farmland may have unrecognized conservation values, although apparently not for forest specialist species. We suggest that conservation policies in south‐western Ethiopia should recognize not only forests, but also the complementary value of the agricultural mosaic—similar to the case of European cultural landscapes. A possible future priority could be to better reintegrate forest species in the farmland mosaic. [ABSTRACT FROM AUTHOR]

Secale L. is a small but important genus that includes cultivated rye. Although genetic diversity of cultivated rye is high, patterns of genetic diversity in the whole genus, and potential factors affecting the distribution of genetic diversity remain elusive. The population structure and distribution of genetic variation within Secale, and its correlation with taxonomic delimitation, cultivation status or spatial distribution in relation to geography and climate zones were analyzed in this study. A collection of 726 individual plants derived from 139 different accessions representing Secale cereale, S. vavilovii, S. strictum, and S. sylvestre were investigated using SSR analysis and sequence diversity analysis of a nuclear EST region. Our results indicated that perennial S. strictum subspecies are genetically divergent from annual forms of the genus. Existence of two distinct clusters within the annual taxa was observed, one corresponding to samples from Asia, and a second to those outside of Asia. No clear genetic structure was observed between different annual species/subspecies, indicating introgression between these taxa. The analysis of cultivated rye revealed that landrace populations from the Middle East have the highest genetic diversity, supporting the idea of the area being the center of origin for cultivated rye. Considering high adaptive potential of those populations, Middle Eastern landraces should be regarded as genetic resources reservoirs for new niches and future breeding programs. [ABSTRACT FROM AUTHOR]

Variation in environmental suitability across the geographic range of a species is common, with consequences for population health and production. Ecological niche modeling (ENM) is an effort to estimate environmental requirements of species based on associations between known geographic occurrences and environmental conditions at those sites, to allow estimation of the potential distribution of the species. We developed an ENM for Hass avocado production fields in Colombia, in which we related the distribution of avocado production lots to environmental information derived from multitemporal MODIS satellite imagery and digital elevation models. Models were calibrated using maximum entropy approaches, using likelihood and information content metrics to optimize model selection; model performance was measured in terms of omission error with respect to independent testing data. Two models were selected that presented best combinations of high information content, significance, and performance based on lower values of Akaike Information Criterion (AICc), partial receiver operating characteristic (partialROC), and low omission of independent testing data records. Suitability values from those models were compared to Hass avocado production; models were able to identify both novel areas with potential for cultivation, and sites where this crop has been planted in relatively unsuitable areas. A statistically significant positive relationship existed between suitability values from the models and avocado production, with different relationships for three technological levels. ENM approaches thus offer a useful and novel tool for exploring and designing sustainable agriculture systems, identifying areas with environmental potential in Colombia and currently not planted with Hass avocado. [ABSTRACT FROM AUTHOR]

The phenotypic and genotypic diversity of natural populations of Lotus corniculatus from three locations in northern Greece was investigated. The collection locations were about 100-140 km apart at altitudes ranging from 50 to 900 m and therefore differed in bioclimatic conditions. The collected plants were transplanted and maintained under the same conditions before their phenotypic and genetic assessment. Plants from high altitudes differed from the low- or moderate-altitude plants in terms of leaf characteristics (smaller leaf area: 1.1 cm2 compared to 1.5 cm2 from the low and moderate altitudes) and internode length (shorter internodes: 2.7 cm compared to 3.2 and 13.1 cm from the low and moderate altitudes respectively). At the genetic level, application of the Inter-Specific Simple Sequence Repeats ( ISSR) molecular markers led to distinct placement of the three populations into different clades of a dendrogram, thus revealing regional diversity. The phytogeographic distinction was also supported by principal components analysis. The results showed that even though phenotypic characters could be close, or even indistinguishable, as in the case of plants from the low and middle altitudes, the genetic background could be different. Therefore, assessment of the natural diversity of L. corniculatus requires a combined and integrative approach involving morphological description and molecular characterization. The natural populations of L. corniculatus constitute valuable germplasm for the development of improved and adapted cultivars. [ABSTRACT FROM AUTHOR]

This study analyzed the characteristics of Korean pine (Pinus koraiensis) functional trait responses to geographic and climatic factors in the eastern region of Northeast China (41°–48°N) and the linear relationships among Korean pine functional traits, to explore this species’ adaptability and ecological regulation strategies under different environmental conditions. Korean pine samples were collected from eight sites located at different latitudes, and the following factors were determined for each site: geographic factors—latitude, longitude, and altitude; temperature factors—mean annual temperature (MAT), growth season mean temperature (GST), and mean temperature of the coldest month (MTCM); and moisture factors—annual precipitation (AP), growth season precipitation (GSP), and potential evapotranspiration (PET). The Korean pine functional traits examined were specific leaf area (SLA), leaf thickness (LT), leaf dry matter content (LDMC), specific root length (SRL), leaf nitrogen content (LNC), leaf phosphorus content (LPC), root nitrogen content (RNC), and root phosphorus content (RPC). The results showed that Korean pine functional traits were significantly correlated to latitude, altitude, GST, MTCM, AP, GSP, and PET. Among the Korean pine functional traits, SLA showed significant linear relationships with LT, LDMC, LNC, LPC, and RPC, and LT showed significant linear relationships with LDMC, SRL, LNC, LPC, RNC, and RPC; the linear relationships between LNC, LPC, RNC, and RPC were also significant. In conclusion, Korean pine functional trait responses to latitude resulted in its adaptation to geographic and climatic factors. The main limiting factors were precipitation and evapotranspiration, followed by altitude, latitude, GST, and MTCM. The impacts of longitude and MAT were not obvious. Changes in precipitation and temperature were most responsible for the close correlation among Korean pine functional traits, reflecting its adaption to habitat variation. [ABSTRACT FROM AUTHOR]

Until now, little attention has been paid to the geographic distribution and evaluation of genetic diversity of durum wheat from the Central Fertile Crescent (modern-day Turkey and Syria). Turkey and Syria are considered as primary centers of wheat diversity, and thousands of locally adapted wheat landraces are still present in the farmers’ small fields. We planned this study to evaluate the genetic diversity of durum wheat landraces from the Central Fertile Crescent by genotyping based on DArTseq and SNP analysis. A total of 39,568 DArTseq and 20,661 SNP markers were used to characterize the genetic characteristic of 91 durum wheat land races. Clustering based on Neighbor joining analysis, principal coordinate as well as Bayesian model implemented in structure, clearly showed that the grouping pattern is not associated with the geographical distribution of the durum wheat due to the mixing of the Turkish and Syrian landraces. Significant correlation between DArTseq and SNP markers was observed in the Mantel test. However, we detected a non-significant relationship between geographical coordinates and DArTseq (r = -0.085) and SNP (r = -0.039) loci. These results showed that unconscious farmer selection and lack of the commercial varieties might have resulted in the exchange of genetic material and this was apparent in the genetic structure of durum wheat in Turkey and Syria. The genomic characterization presented here is an essential step towards a future exploitation of the available durum wheat genetic resources in genomic and breeding programs. The results of this study have also depicted a clear insight about the genetic diversity of wheat accessions from the Central Fertile Crescent. [ABSTRACT FROM AUTHOR]

Phytophthora infestans (Mont.) de Bary, the causal agent of potato late blight, was responsible for the Irish potato famine of the 1840s. Initial disease outbreaks occurred in the US in 1843, two years prior to European outbreaks. We examined the evolutionary relationships and source of the 19th-century outbreaks using herbarium specimens of P. infestans from historic (1846–1970) and more recent isolates (1992–2014) of the pathogen. The same unique SSR multilocus genotype, named here as FAM-1, caused widespread outbreaks in both US and Europe. The FAM-1 lineage shared allelic diversity and grouped with the oldest specimens collected in Colombia and Central America. The FAM-1 lineage of P. infestans formed a genetic group that was distinct from more recent aggressive lineages found in the US. The US-1 lineage formed a second, mid-20th century group. Recent modern US lineages and the oldest Mexican lineages formed a genetic group with recent Mexican lineages, suggesting a Mexican origin of recent US lineages. A survey of mitochondrial haplotypes in a larger set of global herbarium specimens documented the more frequent occurrence of the HERB-1 (type Ia) mitochondrial haplotype in archival collections from 1866–75 and 1906–1915 and the rise of the Ib mitochondrial lineage (US-1) between 1946–1955. The FAM-1 SSR lineage survived for almost 100 years in the US, was geographically widespread, and was displaced first in the mid-20th century by the US-1 lineage and then by distinct new aggressive lineages that migrated from Mexico. [ABSTRACT FROM AUTHOR]

Cytochrome P450 93 family (CYP93) belonging to the cytochrome P450 superfamily plays important roles in diverse plant processes. However, no previous studies have investigated the evolution and expression of the members of this family. In this study, we performed comprehensive genome-wide analysis to identify CYP93 genes in 60 green plants. In all, 214 CYP93 proteins were identified; they were specifically found in flowering plants and could be classified into ten subfamilies—CYP93A–K, with the last two being identified first. CYP93A is the ancestor that was derived in flowering plants, and the remaining showed lineage-specific distribution—CYP93B and CYP93C are present in dicots; CYP93F is distributed only in Poaceae; CYP93G and CYP93J are monocot-specific; CYP93E is unique to legumes; CYP93H and CYP93K are only found in Aquilegia coerulea, and CYP93D is Brassicaceae-specific. Each subfamily generally has conserved gene numbers, structures, and characteristics, indicating functional conservation during evolution. Synonymous nucleotide substitution (dN/dS) analysis showed that CYP93 genes are under strong negative selection. Comparative expression analyses of CYP93 genes in dicots and monocots revealed that they are preferentially expressed in the roots and tend to be induced by biotic and/or abiotic stresses, in accordance with their well-known functions in plant secondary biosynthesis. [ABSTRACT FROM AUTHOR]

Background Grape juice is a beverage derived from Vitis sp genus, mainly V. labrusca, V. vinifera and V. rotundifolia species, in which sales have increased steeply because of the alleged beneficial health effects it exerts when consumed regularly. However, the isolated and interlinked impacts of geographical origin, varietal, and farming system on the juice's chemical composition and functional properties still are not fully comprehended. Scope and approach This paper aims to assess how the producing region, variety, and farming system of grapes (conventional, organic, and biodynamic) affect the quantitative and qualitatively the chemical composition and the functionality ( in vitro , in vivo ) of juices. Key findings and conclusions Data have shown that the effects of botanical and geographical origins of purple grapes on the chemical composition (especially phenolic compounds) and functional properties of juices are remarkable. On the other hand, organic and biodynamic grape juices have very similar composition and functional properties in vitro, while organic and conventional are somewhat different. This evidence is in line with in vivo animal studies and human trials on healthy individuals have shown: differences in functional properties, especially antioxidant effects, between organic and conventional grape juices are negligible from the nutritional and biochemical perspectives. [ABSTRACT FROM AUTHOR]

The wide distribution of many seagrasses may be attributable to exploitation of currents. However, many species have seeds heavier than seawater, limiting surface floating, and thus, deep water becomes a potential barrier between suitable habitats. In this investigation, we studied the dispersal potential of various life history stages of two species of seagrasses, Thalassia hemprichii and Halophila ovalis, at Dongsha Atoll and Penghu Islands in Taiwan Strait, west Pacific. The adult plants of both species, often dislodged naturally from substrate by waves, could float, but only that of T. hemprichii could float for months and still remain alive and potentially able to colonize new territories. The seedlings of T. hemprichii could also float for about a month once failing to anchor to substrate of coral sand, but that of H. ovalis could not. The fruits and seeds of T. hemprichii could both float, but for too short a duration to enable long distance travel; those seeds released from long floating fruits had low germination rates in our tests. Obviously, their seeds are not adaptive for long distance dispersal. Fruits and seeds of H. ovalis do not float. The potential of animals as vectors was tested by feeding fruits and seeds of both species to a goose, a duck, and two fish in the laboratory. The fruits and seeds of T. hemprichii were digested and could no longer germinate; those of H. ovalis could pass through the digestive tracts and have a much higher germination rates than uningested controls. Therefore, birds could be important vectors for long distance dispersal of H. ovalis. The two seagrasses adopted very different dispersal mechanisms for long distance travel, and both exploited traits originally adaptive for other purposes. [ABSTRACT FROM AUTHOR]

A long-term assumption in ecology is that species distributions correspond with their niche requirements, but evidence that species can persist in unsuitable habitat for centuries undermines the link between species and habitat. Moreover, species may be more dependent on mutualist partners than specific habitats. Most evidence connecting indigenous cultures with plant dispersal is anecdotal, but historical records suggest that Native Americans transported and cultivated many species, including Gleditsia triacanthos ("Honey locust"). Gleditsia triacanthos was an important medicinal/culinary (e.g., sugar), cultural (e.g., game sticks) and spiritual tree for the Cherokee (southeastern U.S. Native Americans). This study tests the hypothesis that a Cherokee cultivation legacy drives current regional G. triacanthos distribution patterns. Gleditsia triacanthos occurs in rocky uplands and xeric fields, but inexplicably also occurs in mesic riverine corridors and floodplains where Cherokee once settled and farmed. I combined field experiments and surveys in the Southern Appalachian Mountain region (U.S.) to investigate G. triacanthos recruitment requirements and distribution patterns to determine whether there is a quantifiable G. triacanthos association with former Cherokee settlements. Moreover, I also investigated alternate dispersal mechanisms, such as stream transport and domestic cattle. The results indicate that a centuries-old legacy of Native American cultivation remains intact as G. triacanthos' current southern Appalachian distribution appears better explained Cherokee settlement patterns than habitat. The data indicate that the tree is severely dispersal limited in the region, only moving appreciable distances from former Cherokee settlements where cattle grazing is prevalent. Human land use legacy may play a long-term role in shaping species distributions, and pre-European settlement activity appears underrated as a factor influencing modern tree species distributions. [ABSTRACT FROM AUTHOR]

Background: The distribution of genetic variability from the interior towards the periphery of a species’ range is of great interest to evolutionary biologists. Although it has been long presumed that population genetic variation should decrease as a species’ range is approached, results of empirical investigations still remain ambiguous. Knowledge regarding patterns of genetic variability as well as affected factors is particularly not conclusive in plants. Methodology/Principal Findings: To determine genetic divergence in peripheral populations of the wild rice Oryza rufipogon Griff. from China, genetic diversity and population structure were studied in five northern & northeastern peripheral and 16 central populations using six microsatellite loci. We found that populations resided at peripheries of the species possessed markedly decreased microsatellite diversity than those located in its center. Population size was observed to be positively correlated with microsatellite diversity. Moreover, there are significantly positive correlations between levels of microsatellite diversity and distances from the northern and northeastern periphery of this species. To investigate genetic structure and heterozygosity variation between generations of O. rufipogon, a total of 2382 progeny seeds from 186 maternal families were further assayed from three peripheral and central populations, respectively. Peripheral populations exhibited significantly lower levels of heterozygosities than central populations for both seed and maternal generations. In comparisons with maternal samples, significantly low observed heterozygosity (HO) and high heterozygote deficit within populations (FIS) values were detected in seed samples from both peripheral and central populations. Significantly lower observed heterozygosity (HO) and higher FIS values were further observed in peripheral populations than those in central populations for seed samples. The results indicate an excess of homozygotes and thus high inbreeding depression in peripheral populations. Conclusions/Significance: Our results together suggest that historical contraction of geographical range, demographic changes, and environmental conditions near the northern and northeastern margins of O. rufipogon favor inbreeding and possibly selfing, leading to the rapidly decreased effective population size. Genetic drift, reduced gene flow, and possible local selection, consequently lead to lowered gene diversity, accelerated genetic divergence and increased inbreeding depression found in peripheral populations of O. rufipogon. Given these characteristics observed, northern and northeastern peripheral populations deserve relatively different conservation strategies for either germplasm sampling of ex situ conservation or setting in situ reserves for the adaptation to possible environmental changes and the future germplasm utilization of wild rice. [ABSTRACT FROM AUTHOR]

Nymphaea loriana Wiersema, Hellq. & Borsch (Lori's Water-lily) is a newly described, Canadian endemic species that has been found in central Manitoba and east-central Saskatchewan. To assess the status of a species, data regarding its distribution, population size, habitat, and search effort are needed. The purpose of this paper is to document these factors for this species. The extent of occurrence of N. loriana is approximately 15 100 km2 but the known area of occupancy is a mere 20 km2. The estimated population size of N. loriana is about 750 individual plants, although more may exist on poorly explored rivers and lakes within the extent of occurrence and possibly in northeastern Ontario. Nymphaea loriana occurs in fresh, stagnant, or slowly moving water in boreal lakes and rivers and is typically associated with N. leibergii (Dwarf Water-lily), Schoenoplectus tabemaemontani (Soft-stemmed Bulrush), Potamogeton natans (Floating-leaved Pondweed) and Nuphar variegata (Variegated Pondlily). Potential threats to the persistence of this species include low water quality resulting from mining, forestry, and agriculture, and changes to water flow because of dam construction and climate change. Monitoring known populations and searching for additional ones may be needed to assess the status of this species. [ABSTRACT FROM AUTHOR]

The urban site of Caesarea Maritima located on the Mediterranean coast of modern Israel was founded by King Herod and dedicated to emperor Caesar Augustus between 22 and 10 bce. The site subsequently went through many phases of occupation generally classified as Roman, Late Roman (Byzantine), Early Islamic, Crusader and Mamluk in which cultural and settlement size transitions occurred. This paper offers an analysis from this culturally significant site of the plant remains recovered from three specific areas of Caesarea (Arabic-Qaysariyya) during the Islamic period of occupation from 640 to 1101 ce under the Umayyad, Abbasid and Fatimid dynasties. The Combined Caesarea Expeditions, or CCE, devoted significant attention to archaeobotanical research and recovered samples from several excavation sectors across the site, specifically for the present study areas TP, the Temple Platform; and LL, a warehouse quarter. Although the goals of CCE's project were to study monuments of the Roman and Late Roman (Byzantine) city, a dense Early Islamic domestic occupation was identified that had succeeded the ancient occupation. From these contexts 203 sediment samples were processed by water flotation, 106 of which contained plant remains. There were 9,972 specimens examined from 63 different taxa. The archaeobotanical and supplementary documentary evidence examined clearly demonstrates that the population of Islamic Caesarea put significant investments into local agriculture, carrying on a tradition of practices that likely pre-dated Islam by many centuries. [ABSTRACT FROM AUTHOR]

Abstract: Early stress detection in crop plants is highly relevant, but hard to achieve. We hypothesize that close range hyperspectral imaging is able to uncover stress related processes non-destructively in the early stages which are invisible to the human eye. We propose an approach which combines unsupervised and supervised methods in order to identify several stages of progressive stress development from series of hyperspectral images. Stress of an entire plant is detected by stress response levels at pixel scale. The focus is on drought stress in barley (Hordeum vulgare). Unsupervised learning is used to separate hyperspectral signatures into clusters related to different stages of stress response and progressive senescence. Whereas all such signatures may be found in both, well watered and drought stressed plants, their respective distributions differ. Ordinal classification with Support Vector Machines (SVM) is used to quantify and visualize the distribution of progressive stages of senescence and to separate well watered from drought stressed plants. For each senescence stage a distinctive set of most relevant Vegetation Indices (VIs) is identified. The method has been applied on two experiments involving potted barley plants under well watered and drought stress conditions in a greenhouse. Drought stress is detected up to ten days earlier than using NDVI. Furthermore, it is shown that some VIs have overall relevance, while others are specific to particular senescence stages. The transferability of the method to the field is illustrated by an experiment on maize (Zea mays). [Copyright &y& Elsevier]

Both climatic and edaphic conditions determine plant distribution, however many species distribution models do not include edaphic variables especially over large geographical extent. Using an exceptional database of vegetation plots (n = 4839) covering an extent of ∼55000 km2, we tested whether the inclusion of fine scale edaphic variables would improve model predictions of plant distribution compared to models using only climate predictors. We also tested how well these edaphic variables could predict distribution on their own, to evaluate the assumption that at large extents, distribution is governed largely by climate. We also hypothesized that the relative contribution of edaphic and climatic data would vary among species depending on their growth forms and biogeographical attributes within the study area. We modelled 128 native plant species from diverse taxa using four statistical model types and three sets of abiotic predictors: climate, edaphic, and edaphic-climate. Model predictive accuracy and variable importance were compared among these models and for species' characteristics describing growth form, range boundaries within the study area, and prevalence. For many species both the climate-only and edaphic-only models performed well, however the edaphic-climate models generally performed best. The three sets of predictors differed in the spatial information provided about habitat suitability, with climate models able to distinguish range edges, but edaphic models able to better distinguish within-range variation. Model predictive accuracy was generally lower for species without a range boundary within the study area and for common species, but these effects were buffered by including both edaphic and climatic predictors. The relative importance of edaphic and climatic variables varied with growth forms, with trees being more related to climate whereas lower growth forms were more related to edaphic conditions. Our study identifies the potential for non-climate aspects of the environment to pose a constraint to range expansion under climate change. [ABSTRACT FROM AUTHOR]

Geographic barriers and Quaternary climate changes are two major forces driving the evolution, speciation, and genetic structuring of extant organisms. In this study, we used Pinus armandii and eleven other Asian white pines (subsection Strobus, subgenus Pinus) to explore the influences of geographic factors and Pleistocene climatic oscillations on species in South China, a region known to be centers of plant endemism and biodiversity hotspots. Range-wide patterns of genetic variation were investigated using chloroplast and mitochondrial DNA markers, with extensive sampling throughout the entire range of P. armandii. Both cpDNA and mtDNA revealed that P. armandii exhibits high levels of genetic diversity and significant population differentiation. Three geographically distinct subdivisions corresponding to the Qinling-Daba Mountains (QDM), Himalaya-Hengduan Mountains (HHM) and Yungui Plateau (YGP) were revealed in mainland China by cpDNA. Their break zone was located in the southeastern margin of the Qinghai-Tibetan Plateau (QTP). A series of massive mountains, induced by the QTP uplift, imposed significant geographic barriers to genetic exchange. The disjunct distribution patterns of ancestral haplotypes suggest that a large continuous population of the white pines may have existed from southwest to subtropical China. Repeated range shifts in response to the Pleistocene glaciations led to the isolation and diversification of the subtropical species. The two Taiwanese white pines share a common ancestor with the species in mainland China and obtain their chloroplasts via long-distance pollen dispersal from North Asian pines. Distinct genetic patterns were detected in populations from the Qinling-Daba Mountains, Yungui Plateau, Himalaya-Hengduan Mountains, and subtropical China, indicating significant contributions of geographic factors to the genetic differentiation in white pines. Our study depicts a clear picture of the evolutionary history of Chinese white pines and highlights the heterogeneous contributions of geography and Pleistocene climatic fluctuations to the extremely high plant species diversity and endemism in South China. [ABSTRACT FROM AUTHOR]

Autochthonous germoplasm of the olive with 156 accessions, (O europaea L. ssp. Sativa Hoffm, ssp. O. Oleaster Hoffm, and ssp. Sylvestris), has been analyzed with biological valences of the species (catminate code) and D-GIS (Bioclim / Domain, to identify diversity and suitability of the territory for olive cultivation. Cartography with spatial analysis detects areas of different height diversity levels. (a lot of estimators and variability). In the explored space, 20-37% of the territory resulted excellent for olive cultivation. In the analysis of spatial density, the area of Albania has two major hearths: the Ionian and Adriatic Hearth. In general, 21 genotypes resulted synonyms of 7 standard cv, whereas 21 genotypes resulted homonymous. PCA between correlation matrices of all variables, classified 16 unrelated variables explaining >95 % of total variance. PCoA indexes eigevectors positioned genotypes and their characters according to their degree of variability in negative or positive space. (Axes, x, y and z). [ABSTRACT FROM AUTHOR]

• Proposing a rapid detection model of green pepper based on Yolov4_tiny under complex background. • Improving the Yolov4_tiny network by modifying multi-scale detection, adaptive feature fusion and attention mechanism. • Realizing the rapid detection of green peppers under the conditions of large target scale span, severe occlusion and overlap. • The average precision is 95.11%, the model size is 30.9 MB, and the frame rate is 89 FPS. • The proposed model contributes to monitor the growth of green peppers and automatic picking. In agricultural production, the branches and leaves of green peppers are severely blocked due to the dense plant distribution. This makes the identification of green peppers difficult. Traditional green pepper detection methods entail the problems of low accuracy and poor robustness. This paper introduces a deep learning target detection algorithm based on Yolov4_tiny for green pepper detection. The backbone network in the classic target detection algorithm model is used to ensure classification accuracy. This paper introduces an adaptive spatial feature pyramid method that combines an attention mechanism and the idea of multi-scale prediction to improve the recognition effect of occluded and small-target green peppers. Finally, the method was applied to a test set of 145 images (the target number of green peppers was 602). The AP value of green peppers reached 95.11%; the precision rate was 96.91%, and the recall rate was 93.85%. In order to verify the effectiveness of the module in improving detection performance, we conducted independent combined experiments on the improved module and compared the results with five classic target detection algorithms: SSD, Faster-RCNN, Yolov3, Yolov3_tiny, and Yolov4_tiny. The comparisons verified that the detection rate of the model reached that of the current state-of-the-art technology (SOTA) green pepper detection models. In addition, this green pepper detection model is suitable for real-time detection and embedded development needs of agricultural robots. Such new methods are key components of the technology for predicting green pepper parameters and intelligent picking in unmanned farms. [ABSTRACT FROM AUTHOR]

Phytophthora ramorum, an invasive plant pathogen of unknown origin, causes considerable and widespread damage in plant industries and natural ecosystems of the USA and Europe. Estimating the potential geographical range of P. ramorum has been complicated by a lack of biological and geographical data with which to calibrate climatic models. Previous attempts to do so, using either invaded range data or surrogate species approaches, have delivered varying results. A simulation model was developed using CLIMEX to estimate the global climate suitability patterns for establishment of P. ramorum. Growth requirements and stress response parameters were derived from ecophysiological laboratory observations and site-level transmission and disease factors related to climate data in the field. Geographical distribution data from the USA (California and Oregon) and Norway were reserved from model-fitting and used to validate the models. The model suggests that the invasion of P. ramorum in both North America and Europe is still in its infancy and that it is presently occupying a small fraction of its potential range. Phytophthora ramorum appears to be climatically suited to large areas of Africa, Australasia and South America, where it could cause biodiversity and economic losses in plant industries and natural ecosystems with susceptible hosts if introduced. [ABSTRACT FROM AUTHOR]

Although human-related disturbance is usually detrimental for biodiversity, in some instances it can simulate natural processes and benefit certain species. Changes in the disturbance regime, both natural and human-driven, can affect species that rely on it. The Apennine yellow-bellied toad Bombina variegata pachypus, an amphibian endemic to peninsular Italy, has declined throughout its range in the last 3 decades. We sought to identify the drivers of the decline in the region of Liguria, at the north-western limit of its distribution. In 2009 and 2010 we surveyed sites where the species occurred until 2005 and related the persistence of breeding activity to the characteristics of sites. Populations had disappeared from 50% of the sites between 2005 and 2009. Current breeding sites have less aquatic and bank vegetation, fewer predators and better insolation. Frequent disturbance events (desiccation and floods) were related to reduced vegetation, which in turn may decrease predator densities and increase insolation. In this region disturbance is provided by natural factors or, in the case of artificial water bodies, by regular maintenance carried out by landowners. The widespread land abandonment in Liguria can disrupt disturbance regimes, interrupting the removal of vegetation, and thus rapidly reduce the suitability of artificial sites. This was confirmed in our study, with most abandoned breeding sites occurring in formerly cultivated areas. Possible short-term conservation actions include creating new ponds, maintaining artificial water bodies and clearing vegetation. However, long-term conservation may be more problematic as the land abandonment process is unlikely to be reversed. [ABSTRACT FROM PUBLISHER]

: Opportunities exist for replacing reduced height (Rht) genes Rht-B1b and Rht-D1b with alternative dwarfing genes, such as the gibberellin-responsive gene Rht12, for bread wheat improvement. However, a comprehensive understanding of the effects and mode of action of Rht12 is lacking. In the present study, the effects of Rht12 were characterized by analyzing its effects on seeding vigour, seedling roots, leaf and stem morphology, spike development and carbohydrate assimilation and distribution. This was carried out in the four genotypes of F2:3 lines derived from a cross between Ningchun45 and Karcagi (12) in two experiments of autumn sowing and spring sowing. Rht12 significantly decreased stem length (43%∼48% for peduncle) and leaf length (25%∼30% for flag leaf) while the thickness of the internode walls and width of the leaves were increased. Though the final plant stature was shortened (40%) by Rht12, the seedling vigour, especially coleoptile length and root traits at the seedling stage, were not affected adversely. Rht12 elongated the duration of the spike development phase, improved the proportion of spike dry weight at anthesis and significantly increased floret fertility (14%) in the autumn sowing experiment. However, Rht12 delayed anthesis date by around 5 days and even the dominant Vrn-B1 allele could not compensate this negative effect. Additionally, grain size was reduced with the ability to support spike development after anthesis decreased in Rht12 lines. Finally, grain yield was similar between the dwarf and tall lines in the autumn sowing experiment. Thus, Rht12 could substantially reduce plant height without altering seeding vigour and significantly increase spikelet fertility in the favourable autumn sowing environment. The successful utilization of Rht12 in breeding programs will require careful selection since it might delay ear emergence. Nonetheless, the potential exists for wheat improvement by using Rht12. [ABSTRACT FROM AUTHOR]

The species composition, distribution, ecological-trophic structure and conservation value of macromycetes in Maglenishki Rid (Eastern Rhodopes Mts) is studied. 102 macromycetous species were registered. The predominant part of macromycetes belongs to the class Agaricomycetes (99 species), another part belongs to the Ascomycetes (2 species) and Myxomycetes (1 species). Fifteen macromycetous species are rare for the country eleven of them of high conservation value are included in the Red List of endangered macromycetes in Bulgaria. All taxa are presented with brief chorological data and notes on their distribution in the region. [ABSTRACT FROM AUTHOR]

Patterns that resemble strongly skewed size distributions are frequently observed in ecology. A typical example represents tree size distributions of stem diameters. Empirical tests of ecological theories predicting their parameters have been conducted, but the results are difficult to interpret because the statistical methods that are applied to fit such decaying size distributions vary. In addition, binning of field data as well as measurement errors might potentially bias parameter estimates. Here, we compare three different methods for parameter estimation – the common maximum likelihood estimation (MLE) and two modified types of MLE correcting for binning of observations or random measurement errors. We test whether three typical frequency distributions, namely the power-law, negative exponential and Weibull distribution can be precisely identified, and how parameter estimates are biased when observations are additionally either binned or contain measurement error. We show that uncorrected MLE already loses the ability to discern functional form and parameters at relatively small levels of uncertainties. The modified MLE methods that consider such uncertainties (either binning or measurement error) are comparatively much more robust. We conclude that it is important to reduce binning of observations, if possible, and to quantify observation accuracy in empirical studies for fitting strongly skewed size distributions. In general, modified MLE methods that correct binning or measurement errors can be applied to ensure reliable results. [ABSTRACT FROM AUTHOR]

Abstract: Fluvial hydrosystems are environments with large landscape to water surface ratio and therefore particularly vulnerable to changes in land use. We analysed the connection of environmental conditions in 31 prairie streams of the Pampa Plain (Argentina) with regional phytogeography and surrounding land use. Furthermore, the relationships between riparian conditions, macrophytes and water physico-chemistry on the reach scale were explored by considering nutrient levels, pH, water conductivity, riparian conditions and the presence of in-stream vegetation cover. Streams draining croplands were characterized by better conservation of the riparian zone, lower pH and higher nitrate than those exposed to cattle intrusion. Unlike surrounding land use, our results revealed that regional phytogeography showed only marginal significant effects on streams. Our results also revealed that a particular combination of environmental variables (poor riparian conditions, high total phosphorous, high pH and low nitrate) was detrimental for the presence of macrophytes. However, the abundance of submersed and emergent macrophytes was not dependent on surrounding land use nor on regional phytogeography. [Copyright &y& Elsevier]

Background and aims: Legumes of the genus Lessertia have recently been introduced to Australia in an attempt to increase the range of forage species available in Australian farming systems capable of dealing with a changing climate. This study assessed the diversity and the nodulation ability of a collection of Lessertia root nodule bacteria isolated from different agro-climatic areas of the Eastern and Western Capes of South Africa. Methods: The diversity and phylogeny of 43 strains was determined via the partial sequencing of the dnaK, 16srRNA and nodA genes. A glasshouse experiment was undertaken to evaluate symbiotic relationships between six Lessertia species and 17 rhizobia strains. Results: The dnaK and 16S rRNA genes of the majority of the strains clustered with the genus Mesorhizobium. The position of the strains at the intra-genus level was incongruent between phylogenies with few exceptions. The nodA genes from Lessertia spp. formed a cluster on their own, separate from the previously known Mesorhizobium nodA sequences. Strains showed differences in their nodulation and nitrogen fixation patterns that could be correlated with nodA gene phylogeny. L. diffusa, L. herbacea and L. excisa nodulated with nearly all the strains examined while L. capitata, L. incana and L. pauciflora were more stringent. Conclusion: Root nodule bacteria from Lessertia spp. were identified mainly as Mesorhizobium spp. Their nodA genes were unique and correlated with the nodulation and nitrogen fixation patterns of the strains. There were marked differences in promiscuity within Lessertia spp. and within strains of root nodule bacteria. [ABSTRACT FROM AUTHOR]

The article discusses a study to help understand the winter annual weed performance in terms of frost resistance and re-growth capacity and why some winter annuals are abundant in the spring, winter of both spring and winter in Canada. It cites the use of a collection of facultative winter annual weeds common to Canadian farming systems which include downy brome, shepherd's-purse and narrowleaf hawksbeard. It concludes that the ability of weed species to establish early in the season does not have to depend on freezing tolerance and winter survival.

Tropaeolum leptophyllum G. Don subsp. gracile (Hook. & Arnott) Sparre is described and illustrated. The history and distribution in the wild of the two subspecies of T. leptophyllum are discussed and notes on cultivation are given. [ABSTRACT FROM AUTHOR]

Tropaeolum tricolor Sweet is described and illustrated. Its history and distribution in the wild are discussed and notes on cultivation are given. [ABSTRACT FROM AUTHOR]

Tropaeolum brachyceras Hook. & Arnott is described and illustrated. An account of its history and distribution in the wild is given and notes on cultivation are provided. The hybrid T. × tenuirostre, a cross between T. brachyceras and T. tricolor, is also discussed. [ABSTRACT FROM AUTHOR]

The article discusses the research conducted by the Austrian-born Russian scientist Franz Joseph Ruprecht regarding the origins of the Russian Empire's chernozem, or black soil, located in the country's steppe region. The author is also more broadly concerned with Ruprecht's general contributions to the study of geobotany as well. Ruprecht's microscopic analysis of the soil is explained, which led the scientist to argue that the chernozem was made up of decomposed grasses, thereby refuting the claim that it originated from peat. The relationship between the study of natural science and agriculture in Russia during this time period is also examined.

A calculation is presented that converts plant frequency per plot size sampled to expected frequency per any plot size of interest so as to compare studies that used different plot sizes or to assess degrees of spatial randomness in individual studies that used multiple plot sizes. Expected frequency is exponentially related to measured frequency, being dependent on plot size of interest relative to plot size from which measured frequency was obtained. Expected frequency per plot size of interest (Fe) may be expressed as Fe = 1 - (1 - Fs)r, where Fs is measured frequency per plot size sampled and r is the ratio of plot size of interest to plot size sampled. The calculation assumes that plants are randomly distributed, or approximately so, and criteria for presence of plants in plots are consistent in studies being compared. [ABSTRACT FROM AUTHOR]

Previous studies have compared grassland restoration techniques based on resulting species richness and composition. However, none have determined if different techniques generate different plant distributions in space, which may further impact restoration success. This study tests if there are quadrat-scale (1 m2) differences between paired drilled and broadcast plantings in diversity, composition, and plant distributions. Higher competition intensity in and more contiguous spaces between rows in drill-seeded restorations were hypothesized to result in larger patches of native grasses and exotic species. Two paired drill- and broadcast-seeded plantings were sampled in June 2007 in Iowa, U.S.A. Within 10 quadrats in each planting, we measured species abundance with point intercept sampling and plant distributions by dividing the quadrat into 64 cells and recording the most abundant species in each cell. Drilled and broadcast plantings at both sites had similar Simpson’s diversity and evenness. However, the effect of planting type on species richness, composition, and plant distribution was site dependent. Native warm-season grasses in one site, and exotic species in the second, occupied more space and were distributed in larger patches in drilled plantings. Furthermore, drilled canopies consistently captured more light than broadcast canopies. This suggests that initial differences in seed placement can affect resulting plant distributions, resource use, and potentially long-term species turnover. Mechanisms structuring vegetation in these communities need to be further investigated to determine if this approach can provide more information on long-term diversity maintenance in restorations than traditional measures. [ABSTRACT FROM AUTHOR]

Bolivia is regarded as the probable place of origin of the domesticated peanut, and an important world center of unique peanut diversity. As the first published study of its kind on peanut, this paper documents the infraspecific diversity of the crop in its country of origin and center of diverstity. 62 distinct landraces of Bolivian peanut were identified and systematically described. 42 landraces belong to Arachis hypogaea L. ssp. hypogaea var. hypogaea; 17 to A. hypogaea ssp. fastigiata var. fastigiata; one to A. hypogaea ssp. fastigiata var. vulgaris; and two to A. hypogaea ssp. fastigiata var. peruviana. With very few exceptions, the landraces encountered in Bolivia are almost entirely endemic to that country. The most typical peanuts from Bolivia pertain to the landraces "Crema", "Colorado San Simón", "Bayo americano", "Overo", and "Overo carenado", which are widely cultivated throughout the country. A few regions of unusually high peanut diversity can be identified. In the Yungas region of La Paz, 11 landraces were collected, of which three are endemic. In the mountainous regions of Santa Cruz and Cochabamba, 18 landraces were collected, of which six are endemic. The Department of Tarija yielded 14 landraces, of which two are endemic. All of the aforementioned landraces pertain to the botanical variety hypogaea. In contrast, the subspecies fastigiata has a remarkable center or diversity in the watershed of the Rio Beni, where 10 landraces were collected in a fairly small area, nine of which are endemic to that region. This monograph is intended to enhance the knowledge and appreciation of peanut diversity, and facilitate the conservation and use of peanut landraces by scientistis, plant breeders, and farmers [ABSTRACT FROM AUTHOR]

This paper explores plant and animal distributions inside a Neolithic burned house in order to investigate domestic organization in an early farming society. We use GIS to analyze the spatial distributions of plant and animal remains found inside Building 52 at çatalhöyük in central Anatolia. We examine how plant and animal stores, food and nonfood materials, and wild and domestic taxa were configured spatially. Results shed light on the logistics of early storage, the importance of economic privacy, and the significance of the "domestic" versus "wild" distinction to early farmers. [ABSTRACT FROM AUTHOR]

The bacterias constitute the second group in importance like pathogens of plants. The genus of more importance are Clavibacter, Agrobacterium, Pectobacterium, Pseudomonas and Xanthomonas. The bee-glue has demonstrated microbial action bacterias. The present work had as objectives: to evaluate "in vitro" three concentrations of two extracts of bee-glue of different origin in the inhibition of growth of Pectobacterium carotovorum subsp. atroseptica, Xanthomonas vesicatoria, Clavibacter michiganensis subsp. michiganensis (Cmm), Agrobacterium tumefaciens, Ralstonia solanacearum, Pseudomonas syringae pv. tomato, Pseudomonas corrugata, Xanthomonas campestris pv. cucurbitae, Pseudomonas sevastanoi subsp. sevastanoi, Xanthomonas axonopodis pv. citri and to determine the Inhibitory Minimum Concentration (IMC) and the effect germicide of 15 isolations of Cmm. The microbial activity of bee-glues extracts was carried out by means of the antibiogram technique. IMC of bee-glue extracts was determined in front of isolations of C. michiganensis michiganensis. The extracts of bee-glue of the two origins inhibited the growth of C. m. michiganensis in all the evaluated concentrations. The extract of Cannelonis produced bigger inhibition diameter that that of Rocha. This inhibition difference is also observed in the dose of 120 mg/mL for X. campestris pv. cucurbitae and X. vesicatoria. The bacteria R. solanacearum was inhibited in the concentrations 120 and 80 mg/mL of the bee-glue of Cannelonis and 120 mg/mL of bee-glue of Rocha. None of the extracts inhibited the growth of Pectobacterium carotovorum atroseptica, A. tumefaciens, P. s. pv. tomato, P. corrugata, P. s. pv. sevastanoi, X. to. pv. citri, the same as the control. [ABSTRACT FROM AUTHOR]

Changes in land use have been shown to have profound effects on forest plant community structure and diversity. Dispersal limitation has been invoked as a major factor hampering colonization of forest plant species, while seed-sowing experiments and performance observations have provided some evidence for recruitment limitation determining forest plant distribution in post-agricultural forests. However, most of these studies were relatively short-term, and very few studies have investigated long-term growth rates of populations occurring in recent and ancient forests. In this study, matrix models using demographic data collected for four consecutive years were used to study the effect of forest age on population dynamics of the temperate forest herb Primula elatior. A life table response experiment (LTRE) and elasticity analysis were used to analyze the effect of forest age on population growth rate (A.) and to decompose the effect of forest age on A. into contributions from each matrix element. Population growth increased logarithmically with increasing forest age. Bootstrap analyses showed that populations located in very recent forests (<50 years old) had growth rates that were significantly <1, whereas populations located in forests >150 years old had growth rates that were significantly >1. Summed elasticities for individual growth significantly decreased with increasing forest age, whereas summed elasticities for survival and fertility significantly increased with increasing forest age. The LTRE analysis showed that the increase in ƛ. with increasing forest age was mainly due to increased seedling and juvenile growth and increased juvenile and adult survival. Our results indicate that past agricultural land use has long-lasting effects on the demography of forest herbs and may provide an additional mechanistic explanation for the poor colonization capacity of many forest herbs in post-agricultural forests. [ABSTRACT FROM AUTHOR]

Juniperus excelsa and J. thurifera are considered to originate from the same ancestor. As a result of occurring in geographically isolated refuges – J. excelsa in SE Europe and SW Asia and J. thurifera in SW Europe and NW Africa – their divergence could have taken place at the end of the Tertiary, with the climate cooling. Juniperus foetidissima occurs in SE Europe and SW Asia in territories shared with J. excelsa and is similar to and sometimes misidentified with it. The occurrence of the latter two species over the same area suggests they should be more similar to each other than to the geographically distant J. thurifera. Four populations of J. excelsa ssp. excelsa, four of J. thurifera and two of Juniperus foetidissima were examined on the basis of features of 10 cones and 10 shoots of 18–36 specimens each. Results of discrimination analysis, Mahalanobis distances and cluster analysis showed great similarity to J. excelsa and J. thurifera, while J. foetidissima was more distant. The results support the hypothesis of a common ancestor of J. excelsa and J. thurifera, but suggest another origin of J. foetidissima. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 155, 483–495. [ABSTRACT FROM AUTHOR]

Aim We determined the present and past distribution, and the abundance, of Boswellia papyrifera in Eritrea, and the environmental and land-use factors determining its distribution limits. Location Eritrea, in the Horn of Africa. Methods In 1997 a Boswellia field survey was conducted in 113 village areas covering four administrative regions. Species occurrence was related to rainfall, air temperature and length of growing period. Additionally, the relationship between the abundance of Boswellia trees and selected physical and chemical soil factors, topography and land-use types was determined for five study areas (with a total of 144 plots) situated along an altitude gradient of 800–2000 m a.s.l. Results The geographical distribution of B. papyrifera was limited to the south-western and southern parts of the country between 800 and 1850 m altitude receiving a mean annual rainfall of 375–700 mm, with a growing period of 45–100 days. Species abundance was affected by, in order of importance: altitude, land-use intensity and soil organic matter. Most trees were found in hilly areas; tree density increased from the foot slope to the hill summit; no trees occurred in valleys. Land-use intensity, especially agriculture, fallow and grazed areas, had a profound negative effect on tree abundance. Natural regeneration of the species was promoted in areas where grazing by livestock was not allowed or regulated. Main conclusions The distribution of B. papyrifera in Eritrea has decreased during past decades, mainly due to an increasing human population, resulting in the conversion of woodlands into agricultural fields and increasing livestock pressure hindering natural regeneration. Consequently, Boswellia trees are found mainly in hilly areas on steep slopes with shallow soils of low fertility. The species appears to be able to adapt to these harsh growing conditions: in adjacent countries it was also found in comparable growth habitats. [ABSTRACT FROM AUTHOR]