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Environmental DNA (eDNA) analysis can facilitate surveillance of invasive aquatic plant's distribution. However, it is still questionable how accurately eDNA concentration reflects and predicts aquatic plant abundance. Although previous studies investigated relationships between aquatic plant eDNA concentration and their abundance in freshwater environments, the conclusions were not consistent between the studies. Here, a systematic literature search was conducted to summarize previous findings and meta-analyze the relationships between eDNA concentration and aquatic plant abundance. Hierarchical random-effect meta-analyses showed significant positive, but weak, relationships between them (r = 0.45 in average), meaning that eDNA concentration accounted for approximately 20% of the observed variation in plant abundance. Additionally, the relationships tended to be rather stronger in the field than in the laboratory environments, which may be attributed to limited quantifiability and species specificity of plant coverage as abundance metrics, heterogeneous dispersion of plant eDNA particles, and phenology-dependent eDNA production from plant bodies. The finding indicates that aquatic plant eDNA particles could reflect more regional (but not local) abundance, and thus, eDNA-based abundance estimation might be more appropriate at a broader scale (i.e., lower spatial resolution). Further studies focusing on various environmental parameters and plant ecotypes are needed to clarify the relationship. [ABSTRACT FROM AUTHOR]

The Himalaya and Hengduan Mountains (HDM) are recognized as two global biodiversity hotspots, harboring the world's richest alpine flora. However, to what extent the distribution of alpine plants here is affected by climate change remains largely unknown. Bergenia (Saxifragaceae) are perennial medicinal herbs mainly distributed in the Himalaya-HDM region. In this study, we used bioclimatic data for current and future climate scenarios to assess the impact of climate change on the potential distribution of three Bergenia (Saxifragaceae) species. Our results revealed that the geographical distribution of the studied Bergenia species is primarily influenced by precipitation and elevation. By 2090, the three Bergenia species are expected to show contrasting range changes. The western Himalayan alpine species Bergenia stracheyi is expected to expand its range with 21.93 and 17.36% under the optimistic (SSP1-2.6) and moderate (SSP2-4.5) climate change scenario, respectively, while its distribution will shrink by 5.26% under the pessimistic scenario (SSP5-8.5). The Himalayan mid-elevation species B. ciliata is expected to expand its range from 142.42 to 157.14%. In contrast, the distribution range of the east Himalaya-HDM alpine species B. purpurascens is expected to shrink with 34.88 to 47.24%, with most of the habitats in the southeast chains of the HDM at lower elevation summits being lost. In addition, all three Bergenia species are projected to shift their ranges to higher elevations in response to temperature increases. Overall, we conclude that alpine plants may be more vulnerable to climate change than their congeners at lower elevations, supporting the "nowhere to go" hypothesis. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study is to develop and test the applicability of a rapid in situ plant chemistry profiling technique to determine elemental composition of small-volume plant and soil samples obtained from a woody bioenergy crop species, Populus trichocarpa. Expanding the research tools available to characterize the nutrient element correlations among plant tissue types and soil depths is a critical need in the path of understanding productivity and adaptation of plants to variations in external abiotic and biotic factors and developing sustainable perennial bioenergy crops that are co-optimized for biomass valorization aboveground and carbon sequestration belowground. Methods: Several plant root, stem, and soil samples were tested using laser-induced breakdown spectroscopy (LIBS) to evaluate the presence and distribution of nutrient elements. Samples were tested as collected and after being dried and cross sectioned to evaluate the effectiveness of using LIBS for in situ analysis on plant samples. Results: The collected LIBS spectra show the elemental peaks were the same in both the as collected and prepared samples for roots and stems. Qualitative amounts of elements such as H, C, N, O, Li, Na, Mg, K, Ca, Fe, Al, and Si were able to be identified rapidly in raw samples. Conclusion: Here we demonstrate suitability of LIBS in obtaining rapid, in situ, elemental distribution in plant and soil samples, utilizing only small sample volumes and minimal sample preparation. This demonstration opens up a new rapid phenotyping avenue necessary to fill the asymmetrical knowledge gaps in belowground performance of plant systems. [ABSTRACT FROM AUTHOR]

The presence of Andean plant genera in moist forests of the Brazilian Atlantic Coast has been historically hypothesized as the result of cross-continental migrations starting at the eastern Andean flanks. Here we test hypotheses of former connections between the Atlantic and Andean forests by examining distribution patterns of selected cool and moist-adapted plant arboreal taxa present in 54 South American pollen records of the Last Glacial Maximum (LGM), ca. 19–23 cal ka, known to occur in both plant domains. Pollen taxa studied include Araucaria, Drimys, Hedyosmum, Ilex, Myrsine, Podocarpus, Symplocos, Weinmannia, Myrtaceae, Ericaceae and Arecaceae. Past connectivity patterns between these two neotropical regions as well as individual ecological niches during the LGM were explored by cluster analysis of fossil assemblages and modern plant distributions. Additionally, we examined the ecological niche of 137 plant species with shared distributions between the Andes and coastal Brazil. Our results revealed five complex connectivity patterns for South American vegetation linking Andean, Amazonian and Atlantic Forests and one disjunction distribution in southern Chile. This study also provides a better understanding of vegetation cover on the large and shallow South American continental shelf that was exposed due to a global sea level drop. [ABSTRACT FROM AUTHOR]

Allium macrostemon Bunge, commonly referred to as "no-biru" in Japan, is a widespread wild onion species found across the country. Despite being deeply entwined in ancient Japanese culture, it remains an underutilized crop in Japan. Determining the origins of its domestic populations and understanding their genetic composition is crucial to highlighting the plant's historical significance in Japan. This study aims to bridge this knowledge gap by examining the genetic diversity of 47 A. macrostemon samples from various regions in Japan using RAD-Seq. Our analyses distinguished unique population structures, dividing the samples into three distinct groups: A, B, and C. Notably, groups A and B showed clear evidence of bulb propagation, while group C did not. Group C formed four subgroups: C1, C2, C3, and C4. Hybridization between subgroup C1 and either group A, B, or both, resulted in the emergence of subgroups C2, C3, and C4. Thus, groups A, B, and C1 are posited as the ancestral populations. Additionally, our morphological observations indicated distinct differences among these three groups. Our findings also suggest that human migration may have influenced the plant's distribution, hinting at active usage in the past that later waned, causing its current underutilized status. [ABSTRACT FROM AUTHOR]

In the northern forelands of the Alps, farmers report an increase of Jacobaea aquatica in production grasslands. Due to its toxicity, the species affects grassland productivity and calls for costly control measures. We are investigating the extent to which management practices or climatic factors are responsible for the increase of the species and how the situation will change due to climate change. We tested for effects of management intensity, fertilization, agri-environmental measures, and soil disturbance, and modeled the occurrence of the species under rcp4.5 and rcp8.5 scenarios. The main determinants of the occurrence of the species are soil type and summer rainfall. A high risk is associated with wet soils and > 400 mm of rain between June and August; an influence of the management-related factors could not be detected. Under the climate-change scenarios, the overall distribution decreases and shifts to the wetter alpine regions. Thus, the current increase is rather a shift in the occurrence of the species due to the altered precipitation situation. Under future climatic conditions, the species will decline and retreat to higher regions in the Alps. This will decrease the risk of forage contamination for production grassland in the lowlands. [ABSTRACT FROM AUTHOR]

The goal of this study is to examine the impact of coal power plants on the distribution of natural radionuclides in the environment and its effects on air particulate matter and solid fallout. To this end, spatial distributions and correlations are used to group radionuclides and trace elements. The study also identifies sources of elevated concentrations, such as geogenic, anthropogenic, or agricultural, and provides dose assessments, ecological risk assessments, pollution load indices, and geoaccumulation indices. These findings will inform future research and decision making in managing and regulating natural radionuclides near coal power plants. [ABSTRACT FROM AUTHOR]

Observed climate change leads to the variations in the phenology, physiology, and biochemistry of grape berries, to a shift in the distribution of the grape plant areas and, as a result, to a change in the specialization of associated regions. Using the agroclimatic indicators for a comprehensive assessment of the climate change impact on viticulture, a comprehensive assessment of the grape growth conditions, potential quality of wine, and the climate-related risks in the Crimea and Donbass (on the example of Sevastopol and Artemovsk) over two 30-year periods (1961–1990 and 1991–2020) has been carried out. The results have shown a significant change in climatic conditions: an increase in heat availability in both regions and a decrease in frost susceptibility in the south of Donbass. [ABSTRACT FROM AUTHOR]

Allium macrostemon Bunge, commonly referred to as "no-biru" in Japan, is a widespread wild onion species found across the country. Despite being deeply entwined in ancient Japanese culture, it remains an underutilized crop in Japan. Determining the origins of its domestic populations and understanding their genetic composition is crucial to highlighting the plant's historical significance in Japan. This study aims to bridge this knowledge gap by examining the genetic diversity of 47 A. macrostemon samples from various regions in Japan using RAD-Seq. Our analyses distinguished unique population structures, dividing the samples into three distinct groups: A, B, and C. Notably, groups A and B showed clear evidence of bulb propagation, while group C did not. Group C formed four subgroups: C1, C2, C3, and C4. Hybridization between subgroup C1 and either group A, B, or both, resulted in the emergence of subgroups C2, C3, and C4. Thus, groups A, B, and C1 are posited as the ancestral populations. Additionally, our morphological observations indicated distinct differences among these three groups. Our findings also suggest that human migration may have influenced the plant's distribution, hinting at active usage in the past that later waned, causing its current underutilized status. [ABSTRACT FROM AUTHOR]

Fruiting behaviour and sex form are important goals for Luffa breeders and this study aimed to shed light upon inheritance patterns for both these traits. The hermaphrodite form of Luffa acutangula (known as Satputia) is an underutilized vegetable with a unique clustered fruiting habit. Its desirable traits, such as plant architecture, earliness, as well as contrasting traits like unique clustered fruiting, bisexual flower, and crossability with Luffa acutangula (monoecious ridge gourd with solitary fruits), make it a potential source for trait improvement and mapping of desirable traits in Luffa. In the present study, we have elucidated the inheritance pattern of fruiting behaviour in Luffa using F2 mapping population generated from a cross between Pusa Nutan (Luffa acutangula, monoecious, solitary fruiting) × DSat-116 (Luffa acutangula, hermaphrodite, cluster fruiting). In F2 generation, the observed distribution of plant phenotypes fitted in the expected ratio of 3:1 (solitary vs cluster) for fruit-bearing habit. This is the first report of monogenic recessive control for cluster fruit-bearing habit in Luffa. Herein, we designate for the first time the gene symbol cl for cluster fruit bearing in Luffa. Linkage analysis revealed that SRAP marker ME10 EM4-280 was linked to the fruiting trait at the distance of 4.6 cM from the Cl locus. In addition, the inheritance pattern of hermaphrodite sex form in Luffa was also studied in the F2 population of Pusa Nutan × DSat-116 that segregated into 9:3:3:1 ratio (monoecious:andromonoecious:gynoecious:hermaphrodite), suggesting a digenic recessive control of hermaphrodite sex form in Luffa, which was further confirmed by the test cross. The inheritance and identification of molecular marker for cluster fruiting trait provides a basis for breeding in Luffa species. [ABSTRACT FROM AUTHOR]

In the northern forelands of the Alps, farmers report an increase of Jacobaea aquatica in production grasslands. Due to its toxicity, the species affects grassland productivity and calls for costly control measures. We are investigating the extent to which management practices or climatic factors are responsible for the increase of the species and how the situation will change due to climate change. We tested for effects of management intensity, fertilization, agri-environmental measures, and soil disturbance, and modeled the occurrence of the species under rcp4.5 and rcp8.5 scenarios. The main determinants of the occurrence of the species are soil type and summer rainfall. A high risk is associated with wet soils and > 400 mm of rain between June and August; an influence of the management-related factors could not be detected. Under the climate-change scenarios, the overall distribution decreases and shifts to the wetter alpine regions. Thus, the current increase is rather a shift in the occurrence of the species due to the altered precipitation situation. Under future climatic conditions, the species will decline and retreat to higher regions in the Alps. This will decrease the risk of forage contamination for production grassland in the lowlands. [ABSTRACT FROM AUTHOR]

Phelypaea tournefortii (Orobanchaceae) primarily occurs in the Caucasus (Armenia, Azerbaijan, Georgia, and N Iran) and Turkey. This perennial, holoparasitic herb is achlorophyllous and possesses one of the most intense red flowers among all plants worldwide. It occurs as a parasite on the roots of several Tanacetum (Asteraceae) species and prefers steppe and semi-arid habitats. Climate change may affect holoparasites both directly through effects on their physiology and indirectly as a consequence of its effects on their host plants and habitats. In this study, we used the ecological niche modeling approach to estimate the possible effects of climate change on P. tournefortii and to evaluate the effect of its parasitic relationships with two preferred host species on the chances of survival of this species under global warming. We used four climate change scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP5-8.5) and three different simulations (CNRM, GISS-E2, INM). We modeled the species' current and future distribution using the maximum entropy method implemented in MaxEnt using seven bioclimatic variables and species occurrence records (Phelypaea tournefortii – 63 records, Tanacetum argyrophyllum – 40, Tanacetum chiliophyllum – 21). According to our analyses, P. tournefortii will likely contract its geographical range remarkably. In response to global warming, the coverage of the species' suitable niches will decrease by at least 34%, especially in central and southern Armenia, Nakhchivan in Azerbaijan, northern Iran, and NE Turkey. In the worst-case scenario, the species will go completely extinct. Additionally, the studied plant's hosts will lose at least 36% of currently suitable niches boosting the range contraction of P. tournefortii. The GISS-E2 scenario will be least damaging, while the CNRM will be most damaging to climate change for studied species. Our study shows the importance of including ecological data in niche models to obtain more reliable predictions of the future distribution of parasitic plants. [ABSTRACT FROM AUTHOR]

As an important food crop in China, changes in suitable areas for rice planting are critical to agricultural production. In this study, the maximum entropy model (MaxEnt) was utilized to pick the main climatic factors affecting single-season rice planting distribution and project the potential changes under RCP4.5 and RCP8.5 scenarios. It was clear that rice planting distribution was significantly affected by annual total precipitation, the accumulated temperature during a period in which daily temperature was ≥ 10 °C, the moisture index, total precipitation during April–September, and continuous days during the period of daily temperature ≥ 18 °C, with their contribution being 97.6%. There was a continuous decrease in the area of good and high suitability for rice planting projected from 2021–2040 to 2061–2080, with a respective value ranging from 1.49 × 106 km2 to 0.93 × 106 km2 under the RCP4.5 scenario and from 1.42 × 106 km2 to 0.66 × 106 km2 under RCP8.5 scenarios. In 2081–2100, there was a bit increase in the area of good and high suitability under the RCP4.5 scenario. The most significant increases in good and high suitability were detected in Northeast China, while obvious decreases were demonstrated in the Yangtze River Basin which might be exposed to extreme temperature threat. The spatial potential planting center was characterized by the largest planting area in 25°N–37°N and 98°E–134°E. The north boundary and center of rice cultivation arose to 53.5°N and 37.52°N, respectively. These potential distributions for single-season rice under future climate change can provide a theoretical basis for optimizing rice planting layout, improving cultivation, and adjusting variety and management systems in response to climate change. [ABSTRACT FROM AUTHOR]

Coastal dunes are ecosystems significantly affected by the invasion of alien plants. The specific flora and plant communities across these habitats are currently under serious threat. The study was performed on shifting and stable dunes in Ukraine. We aimed to analyze (i) the alien species composition across Ukrainian coastal dunes, (ii) the division of alien plants by life forms, ecological requirements, introduction time, geographical origin, and naturalization degree; (iii) the distribution of alien plants in accordance with coastal zonation of sandy shores of the Black Sea and Azov Sea regions; (iv) which habitats are invaded more frequently. We found that in the flora of Ukrainian coastal dunes, 16.3% of species are alien; among them, 9.4% are neophytes. Most of them originated from the Mediterranean-Turanian region. Anisantha tectorum, Centaurea diffusa, Bromus squarrosus are the most frequent alien species. Regarding Raunkiaer's system of life forms, 61.6% of alien plants are therophytes. By the soil moisture, submesophytes (45.2%) are predominant. Ecological spectra according to soil acidity, nitrogen content, and salt regime of the soil showed that the alien plants distribution across Ukrainian coastal dunes are determined by the complex influence of different abiotic gradients. The highest number of aliens was observed on shifting dunes (19.3%). The stable dunes are less invaded (14.6%). The alien flora composition differs considerably across these types of dunes as well as across the Black Sea and Azov Sea coasts. Our results showed that the coastal dunes of Ukraine should be in the focus of conservation and management with the position of preventing biodiversity losses caused by alien plant species. [ABSTRACT FROM AUTHOR]

This study presented the determination and distribution of 210Pb in plants using Liquid Scintillation Counting. The analysis method of 210Pb in plants has been improved by optimizing the pulse shape analysis setup,constructing quenched correction curves, as well as consideration of the counting from both 210Pb and its progeny 210Bi. This method was used to test for the determination of 210Pb in samples of three species collected from two sites around a uranium mining facility. [ABSTRACT FROM AUTHOR]

Alexander von Humboldt's depictions of mountain vegetation are among the most iconic nineteenth century illustrations in the biological sciences. Here we analyse the contemporary context and empirical data for all these depictions, namely the Tableau physique des Andes (1803, 1807), the Geographiae plantarum lineamenta (1815), the Tableau physique des Îles Canaries (1817), and the Esquisse de la Géographie des plantes dans les Andes de Quito (1824/1825). We show that the Tableau physique des Andes does not reflect Humboldt and Bonpland's field data and presents a flawed depiction of plant occurrences and vertical succession of vegetation belts, arising from Humboldt's misreading of La Condamine's description (1751). Humboldt's 1815 depiction, by contrast, shows a distribution of high-vegetation belts that is consistent with La Condamine's description, while the 1824 depiction drops innovations made in 1815 and returns to simply showing numerous species' names, thus not applying Humboldt's own earlier zonation framework. Our analysis of contemporary reactions to Humboldt's TPA includes Francis Hall's posthumously published 1834 illustration of Andean plant zonation near Quito and Humboldt's reaction to Hall's critique. Throughout his work on plant geography, Humboldt disregarded some of his own observations, or confused them. At stake was his reputation as an innovator in the field of plant geography and a discoverer of the sequence of high-elevation vegetation belts on the world's mountains. [ABSTRACT FROM AUTHOR]

We analysed the floristic subdivisions of Albania by hierarchical clustering of all the vascular plant species of Albania over a grid of 25 km cells, adapting data from the Vascular Species Distribution Atlas in Albania of (Barina Z (ed.) (2017) Distribution atlas of vascular plants in Albania. Hungarian Natural History Museum, Budapest). We identified the principal axes of variation of the flora and the bioclimatic variables that explain it. We also analysed the bioclimate of Albania by means of a self-organizing map (SOM) of the main climatic variables and the application of the global bioclimatic model of Rivas-Martínez. We compared the analysis based on the flora with that based on the bioclimate. The results divided Albania into eight floristic units corresponding to the main vegetation types (Carpinus orientalis woodlands, Quercus cerris woodlands, Quercus petraea and Fagus sylvatica woodlands, Quercus coccifera woodlands, Quercus coccifera and Quercus ithaburensis woodlands, Pinus heldreichii woodlands, alpine vegetation of North Albania, and alpine vegetation of eastern Albania). Two main trends of variation can be recognized: four elevational belts, strongly correlated with average July temperature, and a north–south subdivision, weakly correlated with annual rainfall and thermal excursion. The bioclimatic analysis (SOM and Rivas-Martínez model) resolves and adds detail to the axis of the elevational belts but cannot discern the north–south subdivision apart from the high mountains. We obtained a division into eight floristic units ordered according to two gradients: four elevational belts, each in turn subdivided into a north-central and a southern province. These two gradients seem to have a broader meaning in Southern Europe, particularly the north–south subdivision at about 30° latitude. The partial mismatch between the bioclimate and the flora indicates that bioclimatic models of Europe are in need of a revision and suggests that the history, in addition to the present-day climate (for instance, the vegetation of the last glacial maximum), can play a role in shaping the biogeography of Southern Europe. [ABSTRACT FROM AUTHOR]

Here, from macrophylogeographic mtDNA empirical data, we propose a scenario for the evolution and speciation of two important forest trees, European black pine and Scotch pine, and their multiple subspecies and varieties. Molecular clock simulations revealed that INDEL variability in the Pinus mitochondrial genome is relatively old, i.e., from the Pliocene-Miocene epoch, and related to historical tectonic continental fluctuations rather than to climate change at a large geographic scale. For conservation and management biodiversity program recommendations, special attention is given to the relationships between different speciation models, historical migration patterns, and differences between peripheral and central populations. Species evolution involves the mixing of different speciation modes, and every speciation mode has different effects on different DNA types (e.g., mitochondrial vs. chloroplast vs. nuclear DNA). The misbalance between the contributions of different meta-population census sizes vs. effective population sizes to asymmetric migration patterns is the result of different genotypes (and subphylogenetic lines) responding to selection pressure and adaptive evolution. We propose initial minimal size of conservation unit (between 3 and 5 ha) from central and marginal natural area of distribution for both species in the dynamic management system for practical forest genetic diversity management. The proposed physical sizes were determined by the effective population size, effective radius of seed distribution data, forest density age dynamics, succession pattern, natural selection pressing and species biology [R-17]. [ABSTRACT FROM AUTHOR]

Climate change is significantly affecting the distribution of plants worldwide. Cyclocarya paliurus (Batal.) Iljinsk. (Juglandaceae), a rare deciduous tree, is a traditional nutraceutical tea owing to its health benefits and appealing flavor. In this study, climatic factors and soil physio-chemical factors were screened using MaxEnt modeling, and suitable habitat areas during three historical periods and under two climatic change scenarios were predicted based on 425 occurrence records. MaxEnt model performance was excellent, showing a high prediction ability, with an average area under curve value of 0.9786 ± 0.0025 and true skill statistic index of 0.9556. Eleven climatic factors, as well as four soil physio-chemical factors, were selected based on jackknife resampling. The habitat suitability simulation for three historical periods (last glacial maximum, mid-Holocene, and 1960–1990) showed that although the high-suitability area for C. paliurus decreased during the three periods, the combined intermediate- and high-suitability area increased. The analysis of the suitable habitat distributions under two global warming scenarios (RCP2.6 and RCP8.5) showed a decline in the suitable habitat area of C. paliurus in response to climatic warming. Our results provide basic references for the management of this species in nature. [ABSTRACT FROM AUTHOR]

Plant species play a crucial role in mediating the activity and community structure of soil microbiomes through differential inputs of litter and rhizosphere exudates, but we have a poor understanding of how plant species influence comammox Nitrospira, a newly discovered ammonia oxidizer with pivotal functionality. Here, we investigate the abundance, diversity, and community structure of comammox Nitrospira underneath five plant species and a bare tidal flat at three soil depths in a subtropical estuarine wetland. Plant species played a critical role in driving the distribution of individual clades of comammox Nitrospira, explaining 59.3% of the variation of community structure. Clade A.1 was widely detected in all samples, while clades A.2.1, A.2.2, A.3 and B showed plant species-dependent distribution patterns. Compared with the native species Cyperus malaccensis, the invasion of Spartina alterniflora increased the network complexity and changed the community structure of comammox Nitrospira, while the invasive effects from Kandelia obovata and Phragmites australis were relatively weak. Soil depths significantly influenced the community structure of comammox Nitrospira, but the effect was much weaker than that from plant species. Altogether, our results highlight the previously unrecognized critical role of plant species in driving the distribution of comammox Nitrospira in a subtropical estuarine wetland. [ABSTRACT FROM AUTHOR]

The relict tree Zelkova carpinifolia (Pall.) K. Koch, ordinarily growing in the Hyrcanian–Euxinian phytogeographic region, is reported for the first time from Iraq, namely the north-east of the country. The site lies on the margin of this species' distribution between the other extant isolated records in the south easternmost region of Turkey and western Iran. Given that this species is extremely rare in neighbouring countries, every single population makes a significant contribution to our understanding of the species' phytogeography and conservation. The oldest individuals reported in the study are 105, 102, 93, 90 and 84 years old, and the average age is 46. The palaeobotanical background, habitat characteristics and information on population characteristics are presented. Additionally, SEM micrographs of Zelkova carpinifolia leaves were taken and compared with published sources. The findings are discussed in the context of the worldwide distribution of the species and its conservation status. [ABSTRACT FROM AUTHOR]

The Neotropical Region (NR) is one of the areas with the most plant diversity globally, and its richness of vascular epiphyte (VE) species is higher than Africa and Asia combined. This richness is a consequence of the heterogeneous climate and geological history of the region, both factors also being responsible for the plant distribution patterns. Here, we aimed to explore the phytogeographic relationships of the VE in the NR using 14,636 identified records from 173 surveys exclusively of VE, carried out in 14 countries and 23 biogeographic provinces, comprising 3849 identified species. We assessed the floristic patterns and relationships with climatic variables by multivariate analysis (cluster and ordination analyses). The clustering formed 13 main groups, partly corresponding to the biogeographic units of the NR. Our results demonstrate consistent floristic patterns confirmed through the analysis of floristic similarity, corroborating previous biogeographic classifications in well-studied areas, while broader patterns were found in poorly studied areas. We found a floristic gradient pattern, which allowed us to understand the relationships between environmental conditions and floristic patterns. Furthermore, we discuss our results under the light of the history that likely shaped the current distribution patterns and richness of the VE in the NR. The VE proved to be an important model for testing biogeographic classifications. We encourage the studies of this synusia in the several geographical gaps that remain in the NR, which undoubtedly will improve further studies and support conservationist policies. [ABSTRACT FROM AUTHOR]

The influence of the Intertropical Convergence Zone (ITCZ) in the emerging South Atlantic region during the late Aptian (Early Cretaceous) is reflected in the spatio-temporal distribution of plant communities recorded in eight Brazilian sedimentary basins. The distribution of the bioclimatic groups of hygrophytes, hydrophytes, tropical lowland flora, upland flora, and xerophytes was quantified using pollen and spores. A predominance of xerophytes from the tropical xerophytic shrubland biome characterized the pre-evaporitic, evaporitic, and post-evaporitic paleoclimatic phases, in particular the evaporitic phase. The region experienced humidity events in the pre-evaporitic and post- evaporitic phases, especially near the paleoequator, where the tropical rainforest biome with two phytophysiognomies (lowland and montane rainforests) prevailed. Increasing humidity had a positive effect on plant diversity. [ABSTRACT FROM AUTHOR]

In the era of anthropocene, global warming tends to alter the distribution range of the plant species. Highly fragile to such changes are the species that are endemic, inhabit higher elevations and show narrow distribution ranges. Predicting and plotting the appropriate suitable habitats and keeping knowledge of how climate change will affect future distribution become imperative for designing effective conservation strategies. In the current study we have used BIOMOD ensemble forecasting to study the current and predict the future potential distribution of Dactylorhiza hatagirea and Rheum webbianum and describe their niche dynamics in Himalayan biodiversity hotspots under climate change scenarios using ecospat R package. Results reveal sufficient internal evaluation metrics with area under curve (AUC) and true skill statistic (TSS) values greater than 0.8 i.e. 0.93 and 0.98 and 0.82 and 0.90 for D. hatageria and R. webbianum respectively, which signifies robustness of the model. Among different bioclimatic variables, bio_1, bio_3, bio_8, bio_14 and bio_15 were the most influential, showing greater impact on the potential distribution of these plant species. Range change analysis showed that both the studied species will show significant contraction of their suitable habitats under future climatic scenarios. Representative Concentration Pathway (RCP) 8.5 for the year 2070, indicate that the suitable habitats could be reduced by about 51.41% and 70.57% for D. hatagirea and R. webbianum respectively. The results of the niche comparisons between the current and future climatic scenarios showed moderate level of niche overlap for all the pairs with D. hatageria showing 61% overlap for current vs. RCP4.5 2050 and R. webbianum reflects 68% overlap for current vs. RCP4.5 2050. Furthermore, the PCA analysis revealed that climatic conditions for both the species vary significantly between current and future scenarios. The similarity and equivalence test showed that the niche between present and future climate change scenarios is comparable but not identical. From the current study we concluded that the influence of climate change on the habitat distribution of these plant species in the Himalayan biodiversity hotspots can be considered very severe. Drastic reduction in overall habitat suitability poses a high risk of species extinction and thereby threatens to alter the functions and services of these fragile ecosystems. Present results can be used by conservationists for mitigating the biodiversity decline and exploring undocumented populations on one hand and by policymakers in implementing the policy of conservation of species by launching species recovery programmes in future on the other. The outcomes of this study can contribute substantially to understand the consequences of climate change in the Himalayan biodiversity hotspots. [ABSTRACT FROM AUTHOR]

The detailed description of the distribution, morphology and relationships with host plants (19 species; 15 new records as host plants) of Manatha albipes from Kerala, India is presented here. Significant differences in the morphology from populations of M. albipes from other areas of India have been described. The larval stages of these moths are polyphagous and cause low to severe damage in host plants. The mitochondrial cytochrome oxidase 1 sequence of 692 bp length was sequenced and deposited in NCBI Genbank with the accession number MN717272.The sequence analysis confirms the identity of M. albipes as distinct from other closely related species of bagworms. M. albipes is not yet a major pest in Kerala but is emerging as a threat in the monocultures of neighbouring states. We demonstrate how many plant species in human altered habitations are carryover sources for M. albipes. Preliminary distribution map and threat analysis of the species in the state based on known land use data using GIS tools indicates large areas of agricultural land to be under threat. [ABSTRACT FROM AUTHOR]

Background and aims: Rumex alpinus is a native plant in the mountains of Europe whose distribution has partly been affected by its utilization as a vegetable and medicinal herb. The distribution of micro and risk elements in its organs is not well-known. The study examined the safety of consuming R. alpinus from the Krkonoše Mountains, the Czech Republic, and the Alps (Austria and Italy). Methods: We determined the total and plant-available content of Fe, Zn, Cu, Mn, Al, As, Cr, Ni, Pb, and Cd in the soil and the total content in organs of R. alpinus. Results: The uptake and distribution of elements by plants were characterized by bioaccumulation (BF) and translocation (TF) factors. The level of elements accumulation by R. alpinus is considerably different, depending on local geological substrates and environmental conditions. Rumex alpinus has considerable tolerance to Zn, Cu, As, Cr, Ni, with an easy accumulation strategy. High Al and Cd content in belowground biomass (rhizome) indicate a defensive mechanism for them. Although the aboveground biomass (emerging, senescent, mature leaves, petiole) has some degree of accumulation of risk elements, the results showed that R. alpinus is an excluder. Conclusion: Rumex alpinus does not accumulate risk elements in organs (leaf and petiole) that are consumed based on the permissible limit according to World Health Organization (2001) and can therefore be used without concern. Caution must, therefore, be taken when consuming these plant parts in heavily contaminated soils. [ABSTRACT FROM AUTHOR]

The influence of the Intertropical Convergence Zone (ITCZ) in the emerging South Atlantic region during the late Aptian (Early Cretaceous) is reflected in the spatio-temporal distribution of plant communities recorded in eight Brazilian sedimentary basins. The distribution of the bioclimatic groups of hygrophytes, hydrophytes, tropical lowland flora, upland flora, and xerophytes was quantified using pollen and spores. A predominance of xerophytes from the tropical xerophytic shrubland biome characterized the pre-evaporitic, evaporitic, and post-evaporitic paleoclimatic phases, in particular the evaporitic phase. The region experienced humidity events in the pre-evaporitic and post- evaporitic phases, especially near the paleoequator, where the tropical rainforest biome with two phytophysiognomies (lowland and montane rainforests) prevailed. Increasing humidity had a positive effect on plant diversity. [ABSTRACT FROM AUTHOR]

The gram pod borer, Helicoverpa armigera (Hübner) is the insect pest of global agricultural importance due to its wide host range and cosmopolitan distribution, which is supported by a strong genetic base. This paper presents genetic diversity of the pest population feeding on different hosts (inter-host) and geographic locations (inter-location) in Uttarakhand Himalayas, India and their micro-evolutionary consequences. A total of 21 inter-host and 17 inter-location populations were studied using both nuclear (SSR markers i.e., 1st tier) and mitochondrial genes (cytochrome b i.e., 2nd tier). In case of inter-host populations, grouping was observed in relation to crop season (Kharif and Rabi), sequential growing of the crops and association of crops with weeds and concurrence of crop growth stages. Interestingly, in both the nuclear and mitogenome analysis, the wheat population stood separate as a major cluster, which might be due to its adaptation towards the crop in recent past in the region. Although there is a differential grouping in SSR and cytb based clustering in inter-location populations, high altitude populations stand separate. The study illustrates ecological and evolutionary driven behavioural adaptations in H. armigera populations in Uttarakhand Himalayan population, India. [ABSTRACT FROM AUTHOR]

Invasion by climbing plants is a major obstacle to successful vegetation recovery from disturbance and land management in some regions. However, it is unclear how different habitats in agricultural landscapes contribute to the diversity and structure of climbing plant assemblages. In this study, we surveyed the diversity and distribution of climbing plants at disturbed sites of three types (abandoned orange orchards, forest–orchard edges and windbreak hedges) in a forest-–terraced orchard mosaic landscape in southwestern Japan. Forest–orchard edges and more recently abandoned orchards tended to have greater climbing plant species richness than most of windbreak hedges and longer-abandoned orchards, which were dominated by kudzu (Pueraria lobata), Humulus scandens, or both. The presence or absence of an overhanging canopy and varying weed control practices in adjacent orchards have created heterogeneous forest–orchard edge conditions that have led to the differentiation of climbing plant assemblages. Repetitive hedge pruning and removal of climbing plants by farmers has created less favourable habitats for many climbing plants. These findings indicate that climbing plant assemblages did not simply correspond to the three focal site types, but rather were determined by 'ecological memory' associated with the effects of past and current agricultural activities and management of neighbouring forests. [ABSTRACT FROM AUTHOR]

We discuss the progress in the field of THz imaging based on time-domain spectroscopy during the last 20 years emphasizing several highlights. These include 3D mapping of the water distribution of plants, THz reflection imaging of samples with arbitrary shape, burn wound imaging and the early diagnosis of diabetic foot disease. These applications greatly benefit from the introduction of fibre-coupled THz time-domain system operated by rugged and portable femtosecond fibre-lasers. THz imaging is a versatile measurement method that has a plethora of practical applications and great promise for the future. [ABSTRACT FROM AUTHOR]

This investigation was carried out during 2012–2013 in order to bring out the forest vegetation of the Finike Forest Planning Unit. The study area is located in the Southwestern part of Turkey within the Mediterranean Basin. Field sampling was undertaken using the old Braun-Blanquet method, and 77 sampled relevés were sampled from the study area. The database consists of 214 vascular plant taxa, dominated by the Mediterranean phytogeographical region and Hemicryptophytes. The sampled relevés were classified using the Modified TWINSPAN, and distribution patterns of the plant communities were analysed using non-metric multidimensional scaling with the integration of the R-Project and JUICE program. Topographic factors were assessed for the interpretation of the differentiation among communities. Five associations, four (Lino corymbuloso-Genistetum acanthocladae, Rhamno nitidae-Quercetum cocciferae, Asparago acutifoli-Pinetum brutia, and Lamio striati-Cedretum libani) of which are new, were defined as belonging to the Mediterranean bioclimatic strata within five classes. The distribution of these five plant associations was highly affected by altitude. [ABSTRACT FROM AUTHOR]

Crops that offer multiple types of value, for example, in terms of economy, culture, and health, frequently lack information on the basic ecological interactions that play a significant role in their persistence. Chayote (Sechium edule, Cucurbitaceae), a widespread squash valued for its nutritious fruit, is one example. We aimed at describing the assemblage of flower visitors to this crop at 2400 m where stingless bees, reported as the main pollinators, are naturally absent. We implemented flower exclusions, performed field observations, and inspection of pollen loads of captured visitors to be able to draw distinctions between primary and secondary pollinators. We recorded a total of 60 species or morphospecies of insects visiting the flowers. Bees, wasps, and flies, present in all sites and consistently carrying abundant pollen, are the main pollinators of S. edule at high altitudes. Our study adds to the building evidence of the fundamental role that native bees and wasps play as crop pollinators in subsistence farming. Basic ecological knowledge is essential to inform agricultural management policies and to foresee preventable food scarcity problems, especially in view of climate change scenarios that predict drastic alterations in plant geographical distributions. [ABSTRACT FROM AUTHOR]

The properties of biomembranes depend on the presence, local structure and relative distribution assumed by the thousands of components it is made of. As for animal cells, plant membranes have been demonstrated to be organized in subdomains with different persistence lengths and times. In plant cells, sitosterol has been demonstrated to confer to phospholipid membranes a more ordered structure while among lipids, glycosphingolipids are claimed to form rafts where they tightly pack with sterols. Glucosylceramides are glycosphingolipids involved in plant signalling and are essential for viability of cells and whole plant. The glucosylceramide-sitosterol structural coupling within PLPC membranes is here investigated by Langmuir films, in silico simulations and neutron reflectometry, unveiling that a strong direct interaction between the two molecules exists and governs their lateral and transversal distribution within membrane leaflets. The understanding of the driving forces governing specific molecules clustering and segregation in subdomains, such as glucosylceramide and sitosterol, have an impact on the mechanical properties of biomembranes and could reflect in the other membrane molecules partitioning and activity. [ABSTRACT FROM AUTHOR]

The relationship between plant species and climatic factors has always been a fundamental issue in plant ecology, and the use of multivariate statistical methods can be effective in revealing the relationship between climatic factors and plant species distribution. Therefore, in this study, climatic factors affecting the distribution of Artemisia sieberi and Artemisia aucheri, widely distributed in Iran, were investigated. For this purpose, 117 climatic factors were used, and to reduce the number of factors and determine the most important effective ones, a factor analysis was used by principal component analysis. The results showed that six factors including heating temperature, spring and summer precipitation, wind, autumn–winter precipitation, and dusty and cloudiness days explained 37.32%, 22.54%, 7.18%, 6.6%, 4.22%, and 4.15% of data variation, respectively. Together these seven factors account for 82% of data variation. The autumn–winter precipitation and heating temperature had the greatest impact on the presence of Artemisia sieberi and Artemisia aucheri, respectively, so that the autumn–winter precipitation was negative in areas where Ar.sieberi is observed. The heating temperature factor is negative in areas where Ar.aucheri is present, while it is positive in areas lacking Ar.aucheri. The study of the effect of environmental factors on Artemisia species distribution is very important in the planning and management of natural resources, and Artemisia is one of the most important plants in the country's rangelands; therefore, the results of this research can be used for practical planning, management, and reclamation of these rangelands. [ABSTRACT FROM AUTHOR]

Aims: Understanding the contributions of abiotic and biotic conditions to soil microbial diversity, structure, and function, remains a central focus in soil biology and biogeochemistry. Here we aim to determine how geography and host plant identity influence these different components of rhizosphere bacterial communities and endosymbionts associated with Acacia heterophylla on Réunion island (Mascarene archipelago, Indian Ocean) and A. koa in the Hawaiian Islands (Hawaiian archipelago, Pacific Ocean). These two tree species are remarkable: they are each other's closest living relatives despite their habitats being more than 16 000 km apart. Methods: Using 16S rRNA amplicon next-generation sequencing data we show that the structure of rhizosphere communities of these two acacias is largely driven by dispersal limitation between sites and local soil chemical conditions within sites. Results: Despite high taxonomic turnover in soils collected from different sites, we found their predicted functions to be largely similar, suggestive of functional redundancy. We also identify a core of rhizosphere taxa associated with both Acacia species in both archipelagos, which included potential nitrogen-fixing mutualists. Isolation and characterisation of rhizobia from root nodules of both acacias further supported strong selection by these plants for the same Bradyrhizobium endosymbionts. Conclusions: Overall, our data suggest that phylogenetically-closely related plants may show remarkably similar selectivity for bacterial mutualists over vast geographic distances. [ABSTRACT FROM AUTHOR]

Mapping the spatial distribution of a plant is a current challenge in ecology. Here, a convolutional neural network (CNN) and 33,798 Sentinel-2 satellite images were used to detect and map forest stands dominated by trees of the genus Pleroma by their magenta-to-deep-purple blossoms in the entire Brazilian Atlantic Forest domain, from June 2016 to July 2020. The Pleroma genus, known for its pioneer behaviour, was detected in an area representing 10.8% of the Atlantic Forest, associated negatively with temperature and positively with elevation, slope, tree cover and precipitation. The detection of another genus by the model, 18% of all the detections contained only pink blooming Handroanthus trees, highlighted that botanical identification from space must be taken with caution, particularly outside the known distribution range of the species. The Pleroma blossom seasonality occurred over a period of ~5–6 months centered on the March equinox and populations with distinct blossom timings were found. Our results indicate that in the Atlantic Forest, the remaining natural forest is less diverse than expected but is at least recovering from degradation. Our study suggests a method to produce ecological-domain scale maps of tree genera and species based on their blossoms that could be used for tree studies and biodiversity assessments. [ABSTRACT FROM AUTHOR]

A comprehensive analysis of the properties of close-cut fractions of hydrotreated and hydrocracked diesel fuels was made to evaluate their usability as a feed of plant for isodewaxing on platinum catalyst. An ideal model of fractional feed distribution in dewaxing plant is constructed. It is shown that more than half of the conventional feed of dewaxing plant is inert material of the process, which needs to be separated and passed to stock-tank winter diesel fuel, besides the reactor. It is shown that heavy fraction of hydrocracked diesel fuel is the most suitable dewaxing feed. [ABSTRACT FROM AUTHOR]

Karst ecosystems are formed by dissolution of soluble rocks, usually with conspicuous landscape features, such as sharp peaks, steep slopes and deep valleys. The plants in karst regions develop special adaptability. Here, we reviewed the research progresses on plant adaptability in karst regions, including drought, high temperature and light, high-calcium stresses responses and the strategies of water utilization for plants, soil nutrients impact, human interference and geographical traits on karst plants. Drought, high temperature and light change their physiological and morphological structures to adapt to karst environments. High-calcium and soil nutrients can transfer surplus nutrients to special parts of plants to avoid damage of high nutrient concentration. Therefore, karst plants can make better use of limited water. Human interference also affects geographical distribution of karst plants and their growing environment. All of these aspects may be analyzed to provide guidance and suggestions for related research on plant adaptability mechanisms. [ABSTRACT FROM AUTHOR]

Purpose: Calcium (Ca2+) is a major structural plant nutrient whose low mobility in the phloem causes deleterious nutritional disorders in non-transpiring organs. Since strontium (Sr2+) and Ca2+ share many chemical properties, Sr2+ is frequently used as a tracer to study Ca2+ cycles in ecosystems. However, the level of agreement between Sr2+ and Ca2+ distribution pattern in plants is debatable, and several studies have reported toxic effects of Sr2+. Therefore, we investigated Sr2+ and Ca2+ uptake rates and distribution pattern to determine how reliably Sr2+ can be used as a tracer of Ca2+ in tomato plants (Solanum lycopersicum L.). Methods: We conducted six independent experiments of various duration: from a few hours to several weeks, in hydroponic and perlite substrate. We treated plants with either Ca2+ or Sr2+ at equivalent concentrations and monitored their accumulation in shoot and fruits. Results: Under short-term exposure (hours), Ca2+ and Sr2+ uptake and distribution within the plant were comparable, while the long-term exposure (days and weeks) to 4 mM Sr2+ reduced transpiration and biomass accumulation. The toxic effect of Sr2+ was more prominent when growth conditions were favourable. Nonetheless, Sr2+ accumulated similarly to Ca2+ in shoot and fruit. Surprisingly, Sr2+ deposition in tomato fruit cell walls prevented blossom end rot (BER) to the same degree as Ca2+. Conclusion: Sr2+ can credibly be used as a tracer of Ca2+ uptake and allocation in the short-term, making Sr2+ a powerful tool to study the factors governing Ca2+ allocation to plant organs, primarily fruit Ca2+ delivery. [ABSTRACT FROM AUTHOR]

Alien invasive plants pose a threat to global biodiversity and the cost of control continues to rise. Early detection and prediction of potential risk areas are essential to minimize ecological and socio-economic costs. In this study, the Maxent model was used to predict current and future climatic conditions to estimate the potential global distribution of the invasive plant Xanthium italicum. The model consists of 366 occurrence records (10 repeats, 75% for calibration and 25% for verification) and 10 climate prediction variables. According to the model forecast, the distribution of X. italicum was expected to shrink in future climate scenarios with human intervention, which may be mainly caused by the rise in global average annual temperature. The ROC curve showed that the AUC values of the training set and the test set are 0.965 and 0.906, respectively, indicating that the prediction result of this model was excellent. The contribution rates of annual mean temperature, monthly mean diurnal temperature range, standard deviation of temperature seasonal change and annual average precipitation to the geographical distribution of X. italicum were 65.3%, 11.2%, 9.0%, and 7.7%, respectively, and the total contribution rate was 93.2%. These four variables are the dominant environmental factors affecting the potential distribution of X. italicum, and the influence of temperature is greater than that of precipitation. Through our study on the potential distribution prediction of X. italicum under the future climatic conditions, it has contribution for all countries to strengthen its monitoring, prevention and control, including early warning. [ABSTRACT FROM AUTHOR]

Information obtained from the analysis of dust, particularly biological particles such as pollen, plant parts, and fungal spores, has great utility in forensic geolocation. As an alternative to manual microscopic analysis of dust components, we developed a pipeline that utilizes the airborne plant environmental DNA (eDNA) in settled dust to estimate geographic origin. Metabarcoding of settled airborne eDNA was used to identify plant species whose geographic distributions were then derived from occurrence records in the USGS Biodiversity in Service of Our Nation (BISON) database. The distributions for all plant species identified in a sample were used to generate a probabilistic estimate of the sample source. With settled dust collected at four U.S. sites over a 15-month period, we demonstrated positive regional geolocation (within 600 km2 of the collection point) with 47.6% (20 of 42) of the samples analyzed. Attribution accuracy and resolution was dependent on the number of plant species identified in a dust sample, which was greatly affected by the season of collection. In dust samples that yielded a minimum of 20 identified plant species, positive regional attribution was achieved with 66.7% (16 of 24 samples). For broader demonstration, citizen-collected dust samples collected from 31 diverse U.S. sites were analyzed, and trace plant eDNA provided relevant regional attribution information on provenance in 32.2% of samples. This showed that analysis of airborne plant eDNA in settled dust can provide an accurate estimate regional provenance within the U.S., and relevant forensic information, for a substantial fraction of samples analyzed. [ABSTRACT FROM AUTHOR]

The current research was carried out in Wadi Elkor, one of the Sarawat Mountains regions, which is a special location from an environmental standpoint and one of the only places in Saudi Arabia where a range of Palaearctic flora co-exists with Afrotropical species. The study aimed to determine the floristic composition as well as the effects of slope aspect and elevation on species, life forms, and phytogeographical elements distribution. The study area is located in Wadi Elkor, a valley in the Sarawat Mountains that cuts off the Al-Hada escarpment, 47 km southeast of Makkah City, Saudi Arabia. We conducted the research at three different locations, each with a different elevation and slope aspect. Based on floristic composition, Ward classification moreover Jaccard comparisons were performed. A total of 189 species was discovered, divided into 131 genera and 43 families. The current study identified Argyrolobium rarum Dumme as a new vascular plant in Saudi Arabia's terrestrial flora. In the current study, the Gramineae, Leguminosae, and Compositae families contributed 29% of the total plant species, whereas 14 families were represented by one species each. Solanum was the most numerous genus, with seven species, followed by Acacia and Pulicaria, each with six species, while Commicarpos and Euphorbia, each with four species. At an elevation of 1060 m above sea level, the north facing slope had the most plants, genera, and families. Therophytes had the most species, accounting for 44%, followed by Chamaephytes, which accounted for 26%. Hemicryptophytes accounted for 12% of the total, while phanerophytes accounted for 10%. In the studied area, the bioregional Saharo-Sindian and Sudano-Zambesian groups were the most well-represented (41%). The floristic composition, as well as the distribution of life forms and phytogeographical components, were found to be significantly affected by the elevation and slope aspects. The study showed that slope aspect and elevation both affected the distribution of plant species, with elevation being the most influential of the two variables. [ABSTRACT FROM AUTHOR]

Picrorhiza kurrooa is an endangered medicinal herb which is distributed across the Himalayan region at an altitude between 3000–5000 m above mean sea level. The medicinal properties of P. kurrooa are attributed to monoterpenoid picrosides present in leaf, rhizome and root of the plant. However, no genomic information is currently available for P. kurrooa, which limits our understanding about its molecular systems and associated responses. The present study brings the first assembled draft genome of P. kurrooa by using 227 Gb of raw data generated by Illumina and PacBio RS II sequencing platforms. The assembled genome has a size of n = ~ 1.7 Gb with 12,924 scaffolds. Four pronged assembly quality validations studies, including experimentally reported ESTs mapping and directed sequencing of the assembled contigs, confirmed high reliability of the assembly. About 76% of the genome is covered by complex repeats alone. Annotation revealed 24,798 protein coding and 9789 non-coding genes. Using the assembled genome, a total of 710 miRNAs were discovered, many of which were found responsible for molecular response against temperature changes. The miRNAs and targets were validated experimentally. The availability of draft genome sequence will aid in genetic improvement and conservation of P. kurrooa. Also, this study provided an efficient approach for assembling complex genomes while dealing with repeats when regular assemblers failed to progress due to repeats. [ABSTRACT FROM AUTHOR]