Populus Nigra Research Articles

Внутривидовые скрещивания выделенных биотипов родов вяз и тополь для получения гетерозисных селекционных форм

Abstract. The purpose of the study is hybridization and breeding of tree species resistant to environmental conditions in conditions of desertification. Research methodology included the study of the growth, condition and durability of forms and hybrids, the identification of biological properties (drought, salt and frost resistance), the quality of trunks and decorativeness, the selection of parent pairs for crossing; the development of crossing techniques on cut branches. The order of work consisted of harvesting plant catkins, collecting pollen and cleaning it from impurities, harvesting branches and pollen, determining the viability of pollen, applying it to the mature stigma of the plant. The flowers of the ilmovs are bisexual, as a result of which they were castrated during crosses. Results. Parental pairs were selected and hybridization was carried out among the following breeds: Ulmus carpinifolia, Ulmus laevis, Ulmus pumila, Populus alba, Populus alba × Populus alba v. Populus piramidalis, Populus deltoides, Populus bolleana, Populus berolinensis, Populus nivea × Populus tremula, Populus nigra piramidalis. Hybrid seedlings were obtained between different types of elms and between different types of poplars. The variant of crossing the white poplar Pervenets Uzbekistana with the Bolle F. pyramidal poplar (FGUP “Volgogradskoe”) showed the best results. Scientific novelty lies in the selection of breeding material resistant to various stress factors. Selection of initial and promising varieties of tree crops for further use in breeding, introduction, competitive and production tests.

Tree tracking: species selection and traceability for sustainable and biodiversity-friendly urban reforestation

The current climate change and increasing climate variability represent a serious global challenge that demands urgent responses. Among the multiple actions that should be taken, afforestation and reforestation are the most common strategies. The current paper aims to assess the potential of tree species to be used in urban forestry in the Po Plain ecoregional province (Northern Italy) using DNA barcoding approach for plant traceability and ecophysiological indexes (shade, drought and waterlogging) for plant selection. DNA barcoding markers results showed a 55.5% of success, but the power of discrimination increased to 94.5% when considering only the autochthonous ecoregional species pool. Concerning ecophysiological markers, Fagus sylvatica, Abies alba, Picea abies and Taxus baccata were very shade-tolerant. The best performing trees concerning drought tolerance were oak species (Quercus ilex, Q. pubescens and Q. cerris), pines (Pinus pinea, P. nigra and P. sylvestris) and Fraxinus ornus. Only a few tree species (Salix alba, Alnus glutinosa, Populus nigra and Prunus padus) showed high tolerance to waterlogging. The combination of both approaches makes it possible to select the most suitable species, based on eco-pedological and microclimatic conditions, and to trace their identity along the entire supply chain, from nursery to planting, for urban forestry.

Biodiversity of epiphytic cyanobacteria and algae in conditions of road pollution in Ufa

Studies of epiphytic cyanobacterial-algal cenoses along the highways of Ufa were carried out on five species of woody plants: deciduous (Betula verrucosa Ehrh., Populus nigra L., Tilia cordata Mill., Sorbus aucuparia L.) and coniferous (Picea obovata Ledeb.). A large species diversity of algoepiphytes from 5 divisions, 7 classes, 12 orders, 30 families, 48 genera and 85 species and intraspecific taxa was revealed. Epiphytes of the divisions Chlorophyta and Cyanobacteria dominated (41 and 38 species and intraspecific taxa, respectively), leading families - Oscillatoriaceae and Chlorococcaceae, genera - Phormidium, Leptolyngbya, Nostoc, Chlorococcum.The ecological analysis made it possible to identify six morphotypes. The predominance of colonial-coccoid algae was shown, which made up 31 taxa (36.5 % of the total). Trichal forms take the second place - 26 species (30.6 %), coccoid immobile - 22 species (25.9 %). The spectrum of ecobiomorphs of epiphytic cyanoprokaryotes and algae included 11 life forms: Ch32P16C11CF6aer6H4X4PF3hydr1B1аmph1. Oligoatmophytes have the highest species representation -77 %, mesoatmophytes - 17 %, the group of polyatmophytes is sharply depleted - 6 %. Comparison of the obtained results with the control in ecologically clean habitats showed no difference in the taxonomic and ecological composition of cyanobacterial-algal growths, the number of living cells.

Historical disconnection from floodplain alters riparian forest composition, tree growth and deadwood amount

Riparian forests are among the most dynamic but threatened terrestrial ecosystems. Their dynamism and conservation depend on historical changes in river geomorphology, which can be evaluated through changes in channel sinuosity. However, we lack long-term assessments on sinuosity and how they impact riparian forest composition, tree growth and deadwood amount. To fill this research gap, we reconstructed river sinuosity in 14 sites across the middle Ebro basin, north-eastern Spain, using historical aerial photographs taken in 1927, 1956, 1998–2003 and 2014–2015. Relationships between sinuosity, stand composition and deadwood amount and decay degree were calculated. We also reconstructed radial growth of the major tree species (Populus alba, Populus nigra, Fraxinus angustifolia, Salix alba and Ulmus minor) in two sites to evaluate how coupled it was with changes in river flow after dam building. From 1927 to 2015, sinuosity decreased passing from 1.39 to 1.20. The river dynamics were altered in the 1950s and 1960s after dam and dyke building. Sites with high sinuosity values in 1956 corresponded to mature stands with large P. nigra individuals. Sinuosity was negatively related to F. angustifolia (rs = −0.83, p < 0.001) and P. alba (rs = −0.64, p = 0.02) abundance, whereas sites dominated by P. alba and U. minor presented abundant decayed deadwood. A loss of sinuosity and a contraction of the riverbank gradient increased disconnection of active channel from floodplain, with a mixing of more (e.g., P. nigra) and less phreatophytic species (e.g., U. minor). River flow diversion reduced growth and increased the tree-to-tree P. alba growth coherence. Hydrological droughts contributed to growth decline and dieback of U. minor, which is sensitive to spring river flow. Conservation and restoration of riparian forests must consider historical changes in river geomorphology related to human activities.

Diversity, Distribution and Vegetation Assessment of Woody Plant Species in the Cold Desert Environment, North-Western Himalaya, India

The species richness, distribution and community structure in cold desert regions across the world are poorly understood because of their inaccessibility and remoteness. Similarly, the structure and composition of forest resources, including other management units (i.e., agroforestry and forestry systems), have hardly been studied in the cold desert of the Lahaul valley. However, such information is a prerequisite to understanding the trends and changes in the vegetation distribution under global climate change scenarios, especially considering the sensitivity of plant species in high-altitude areas of the Himalayan region. High anthropogenic activity has exerted tremendous pressure on available forest resources, including other management units in the cold desert of the Lahaul valley. Standard ecological methods were used to obtain an ecological (i.e., status, structure, composition and vegetation patterns) understanding of the region for biodiversity conservation and environmental sustainability. The present study was aimed at understanding the trend, structure and composition of plant species in the cold desert region of the western Himalaya. A total of 64 species (27 trees and 37 shrubs) of vascular plants were recorded in the present study. Tree diversity demonstrated greater variation along the gradients and slope aspects. Salix fragilis trees, with a 102 tree ha−1 density and a few trees of Populus nigra, were found to be sparsely distributed under the agroforestry system on the south-facing slopes in Khoksar. In Jahlma, Salix fragilis grew in an agroforestry system with a density of 365 tree ha−1. However, in Hinsa, Juniperus polycarpos was a dominant tree species in the agroforestry system, with a density of 378 tree ha−1. On the north-facing slopes in Kuthar, a higher number of trees and bushes were present due to natural regeneration maintained by farmers along the edges of terraced agricultural fields. The south-facing slopes showed a relatively lower species richness and diversity as compared to north-facing slopes at similar locations due to relatively less favourable growth conditions under sun-exposed, extremely xeric soil conditions. The highest level of species turnover was found between the altitudes of 2400 m and 3000 m. Betula utilis showed the highest adaptability at higher altitudes (&gt;3500 m). The vegetation analysis results and information generated in the present study are useful for gaining an ecological understanding of the cold desert ecosystem in the Lahaul valley. Sustainable forest resource management, including other management units (e.g., agroforestry and forestry systems), is crucial for improving the vegetation pattern, structure and function of the cold desert ecosystem, thereby contributing to climate change mitigation, adaptation, biodiversity and ecosystem service conservation.

Nonlinear kinetic modeling of malachite green adsorption onto green waste bio-adsorbents using CCF- RSM

Malachite Green (MG) adsorption by four different bio-adsorbents: Populus Nigra (PN), Pinus Strobus (PS), Fraxinus Excelsior (FE), and Phragmites Australis (PA) have been investigated. Fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) analyses were conducted to identify the bio-adsorbents' characterization and study their adsorptive properties. The impact of essential factors, such as adsorbent dosage, initial solution pH, initial MG concentration, and interaction of factors were studied on removal efficiency by face centered design (CCF) as a feature of response surface methodology (RSM). Nonlinear kinetic models including pseudo-first, and pseudo-second order, Elovich, film diffusion, and intra-particle diffusion were evaluated using error functions in order to find the best fitted model. Comparing the obtained results revealed that PA is more effective in decolorization and has an uptake of about 90% in the optimum operating condition. For further investigation, its ashes have been used for MG removal, and as a result, 99.3% dye uptake by PA ash was obtained.

Three-dimensional model construction and wind simulation of different tree species in farmland shelter.

Protective forests are the ecological barriers of oases in arid sand areas and can effectively prevent and control wind and sand hazards. The structural characteristics of individual trees, as the basic unit of protective forests, are the key factors affecting the protective benefits. With the typical leafless tree species of Ulan Buh Desert oasis, i.e., Populus alba var. pyramidalis, Populus nigra var. thevestina, and Populus popularis, as the research objects, and by using the ground-based LiDAR and through computational fluid dynamics (CFD), we fully explored the structural characteristics of individual trees and their surrounding aerodynamic characteristics on the basis of real 3D models. We further established the relationship between structural parameters of individual trees and wind field index. The results showed that combining AdQSM and MeshLab to build tree models had high accuracy. The wind field around the individual trees could be roughly divided into six regions, including the attenuation zone of the windward side of the plant, the acceleration zone at the top of the plant, the eddy zone, the calm zone, the transition zone, and the recovery zone of leeward side of the plant. The pressure field around individual trees showed a gradual change of high pressure on the windward side to low pressure on the leeward side. Horizontally, in the range of 20% to 50% reduction in relative wind speed, the effective protection distances were 0.21H-1.51H, 0.20H-0.91H, and 0.25H-1.64H (H was the corresponding tree height) for P. alba var. pyramidalis, P. nigra var. thevestina, and P. popularis, corresponding to effective protection areas of 18-294, 15-227, and 18-261 m2, respectively. The maximum wind speed decay rate in the vertical direction was at 0.3H height for P. alba var. pyramidalis and P. popularis, and was reflected at 0.5H height for P. nigra var. thevestina. The correlation and stepwise regression analysis of the single tree structure parameters with the wind field indicators clearly indicated that optical porosity and volume porosity dominated the protection effect. Among the wind field factors, the best regression models related to the porous coefficient were screened for three factors, including diameter at breast height, tree surface area, and optical porosity. The regression variables screened for effective protection distance and effective protection area differed among the classes.

Diversity of woody flora in Isparta Gölcük Nature Park and its relations with environmental variables

Ormancılıkta flora üzerine gerçekleştirilen çalışmalar sürdürülebilir ormancılık ve biyolojik çeşitlilik üzerine önemli bilgiler vermektedir. Bu çalışma Gölcük Tabiat Parkında odunsu flora çeşitliliğinin belirlenerek çevresel değişkenlerle ilişkilerini ortaya koymak amacıyla gerçekleştirilmiştir. Çalışmada arazi envanteri ile 20x20 metre boyutlarında 25 örnekleme alanı alınmıştır. Her bir örnekleme alanı için odunsu bitki taksonları ve yetişme ortamı özellikleri envanter defterine kaydedilmiştir. Kümeleme analizi ile kesme seviyelerinden elde edilen grupların en uygun olanını tespit edebilmek amacıyla çoklu permütasyon testi (MRPP) uygulanmış en etkili vejetasyon grup ayrımının gösterge bitki türlerini tespit edebilmek amacıyla gösterge bitki analizi uygulanmıştır. Alfa çeşitlilik indis değerleri ile çevresel faktörler arasındaki ilişkileri ortaya koyabilmek adına Pearson korelasyon analizi uygulanmıştır. Pinus nigra, Rosa canina, Populus nigra subsp. caudina ve Malus sylvestris subsp. sylvestris türlerinin çalışma alanın genelinde en sık rastlanan türler olduğu belirlenmiştir. Çalışmada en uygun odunsu grup ayrımı 3’lü grup ayrımında elde edilmiştir. İstatistiksel analizler neticesinde en uygun vejetasyon grup ayrımlarının oluşmasında bakı farklılıklarının önem arz ettiği belirlenmiştir. Bu sonuç tür çeşitliliğinin yörede güneyli bakılarda kuzeyli bakılara kıyasla daha fazla olduğunun tespit edilmesi ile desteklenmiştir.

Assessment of the ecological state of green spaces of Almaty city on the example of Bostandyk district

The article provides an assessment of the ecological state of green spaces on the example of the Bostandyk district of Almaty. The total area of boulevards, squares and green areas of the Bostandyk district of Almaty today is 147.4 hectares. Bostandyk district of Almaty is one of the three greenest districts of Almaty after Medeu and Turksib districts. As our studies have shown, 95 % of green plantations of tree species in the Bostandyk district of Almaty are represented by introducers and a small part of local species — natives. The landscaping of the territory of the city of Almaty is represented by plantings of different types. These include groves, alleys, gardens, parks, boulevards, squares, green areas, intra-district gardening, street gardening. At the same time, a wide variety of species is observed in gardens, parks, boulevards, groves and a very small use of three or four species in landscaping streets. Among the tree plantations, 35 species are massive, which grow along all the streets, boulevards, squares of the Bostandyk district. From hardwoods: Populus nigra, Populus italica, Populus alba, Fraxinus excelsior and others. From the local natural flora grow — Armeniaca vulgaris, Prunus sogdiana, Fraxinus sogdiana, Rhamnus cathartica, Picea schrenkiana.

Soil amendment and rhizobacterial inoculation improved Cu phytostabilization, plant growth and microbial activity in a bench-scale experiment.

Mine driven trace elements' pollution entails environmental risks and causes soil infertility. In the last decades, in situ techniques such as phytostabilization have become increasingly important as ways to tackle these negative impacts. The aim of this study was to test the individual and combined effects of different aided phytostabilization techniques using substrate from barren tailings of a Cu mine, characterized by extreme infertility (high acidity and deficiency of organic matter and nutrients). The experiment analyzed the growth of Populus nigra L. planted alone (P) or in co-cropping with Trifolium repens L. (PT), in pots containing mine soil amended with compost (1, 10, compost, soil, w/w) non inoculated (NI) or inoculated with plant growth promoting rhizobacteria (PGP), mycorrhizae (MYC) or a combination of bacterial and fungal inocula (PGPMYC). Non-amended, non-planted and non-inoculated reference ports were also prepared. Plants were harvested after 110 days of plant development and several biometric and phytopathological parameters (stem height, aerial biomass, root biomass, wilting, chlorosis, pest and death) and macro and micronutrient composition were determined. The growth substrate was analyzed for several physicochemical (pH, CECe, and exchangeable cations, total C and N, P Olsen and availability of trace elements) and microbiological (community level physiological profiles: activity, richness and diversity) parameters. The use of the amendment, P. nigra plantation, and inoculation with rhizobacteria were the best techniques to reduce toxicity and improve soil fertility, as well as to increase the plant survival and growth. Soil bacterial functional diversity was markedly influenced by the presence of plants and the inoculation with bacteria, which suggests that the presence of plant regulated the configuration of a microbial community in which the inoculated bacteria thrive comparatively better. The results of this study support the use of organic amendments, tolerant plants, and plant growth promoting rhizobacteria to reduce environmental risk and improve fertility of soils impacted by mining.

Alkaline soil primes the recovery from drought in Populus nigra plants through physiological and chemical adjustments

Perennial plants are frequently exposed to severe and prolonged drought, and when the balance between water transport and transpirational demand is compromised trees are in danger of embolism formation. To maintain the physiological balance, plants can rely on mechanisms to quickly recover the lost xylem hydraulic capacity and reduce the prolonged impact on photosynthetic activity upon rehydration. Among factors helpful for plants to sustain acclimation and adaptation responses to drought and promote recovery, maintaining an optimal nutritional status is crucial for plant survival.This study aimed to investigate the physiological and biochemical responses under drought and recovery of Populus nigra plants grown in soil with impaired nutrient bioavailability obtained by adding calcium oxide (CaO) to the substrate. Although the CaO treatment did not affect plant growth, in well-watered conditions, treated poplars displayed an impaired inorganic ions profile in tissues. Under drought, although CaO-treated and untreated plants showed similar physiological responses, the former closed the stomata earlier. During water stress relief, the CaO-treated poplars exhibited a faster stomatal opening and a higher capacity to restore xylem hydraulic conductivity compared to not-treated plants, probably due to the higher osmolyte accumulation during drought. The content of some inorganic ions (e.g, Ca2+ and Cl−) was also higher in the xylem sap collected from stressed CaO-treated plants, thus contributing to increase the osmotic gradient necessary for the recovery. Taken together, our results suggest that CaO treatment promotes a faster and more efficient plant recovery after drought due to a modulation of ions homeostasis.

Adding a missing piece to the puzzle of oomycete phylogeny: the placement of Rhipidium interruptum (Rhipidiaceae).

Oomycetes are a group of fungus-like organisms, which phylogenetically comprise early diverging lineages that are mostly holocarpic, and two crown classes, the Peronosporomycetes and Saprolegniomycetes, including many well-investigated pathogens of plants and animals. However, there is a poorly studied group, the Rhipidiales, which placement amongst the crown oomycetes is ambiguous. It accommodates several taxa with a sophisticated vegetative and reproductive cycle, as well as structural organisation, that is arguably the most complex in the oomycete lineage. Despite the remarkable morphological complexity and their notable perseverance in the face of faster-growing saprotrophic oomycetes and fungi, the knowledge on Rhipidiales is limited to date, as the most complex members are not easily cultured, even by targeted approaches. This also leads to inadequate sequence data for the order, which was sourced from only the two least complex out of seven introduced genera, i.e. Sapromyces and Salispina. In the present study, ex-situ baiting was done using various fruit substrates, and naturally-shed twigs or fruits acquired from water bodies were examined. As a result of these efforts, the species Rhipidium interruptum was obtained and gross cultivation was accomplished using poplar (Populus nigra) twigs as substrate, which allowed further documentation of both asexual and sexual reproduction. This enabled phylogenetic and detailed morphological study, as well as an epitypification of the species. Phylogenetic analyses based on cox2 and nrLSU sequences revealed Rhipidium as the sister genus of Sapromyces. The morphological studies done support a conspecificity of R. interruptum and R. continuum, which might in turn be conspecific with R. americanum. Though several further studies will be required to fit the scattered missing pieces of knowledge on Rhipidiales together revealing a more complete picture of oomycete evolution, we hope that the current study can serve as a cornerstone for future investigations in the group. Citation: Tsai I, Thines M (2023). Adding a missing piece to the puzzle of oomycete phylogeny: the placement of Rhipidium interruptum (Rhipidiaceae). Fungal Systematics and Evolution 11: 95-108. doi: 10.3114/fuse.2023.11.08.

Key hydraulic traits control the dynamics of plant dehydration in four contrasting tree species during drought.

Trees are at risk of mortality during extreme drought, yet our understanding of the traits that govern the timing of drought-induced hydraulic failure remains limited. To address this, we tested SurEau, a trait-based soil-plant-atmosphere model designed to predict the dynamics of plant dehydration as represented by changes in water potential, against those observed in potted trees of four contrasting species (Pinus halepensis, Populus nigra, Quercus ilex, and Cedrus atlantica) exposed to drought. SurEau was parameterised with a range of plant hydraulic and allometric traits, soil, and climatic variables. We found close correspondence between predicted and observed plant water potential (MPa) dynamics during early phase drought leading to stomatal closure, as well as during latter phase drought leading to hydraulic failure in all four species. A global model's sensitivity analysis revealed that for a common plant size (leaf area) and soil volume, dehydration times from full hydration to stomatal closure (Tclose) was most strongly controlled by leaf osmotic potential (Pi0) and its influence on stomatal closure, in all four species, while maximum stomatal conductance (gsmax) also contributed to Tclose in Q. ilex and C. atlantica. Dehydration times from stomatal closure to hydraulic failure (Tcav) was most strongly controlled by Pi0, the branch residual conductance (gres), and Q10a sensitivity of gres in the three evergreen species, while xylem embolism resistance (P50) was most influential in the deciduous species Populus nigra. Our findings point to SurEau as a highly useful model for predicting changes in plant water status during drought and suggest adjustments made in key hydraulic traits are potentially beneficial to delaying the onset of drought-induced hydraulic failure in trees.

Analysis of Poplar’s (Populus nigra ita.) Root Systems for Quantifying Bio-Engineering Measures in New Zealand Pastoral Hill Country

Populus nigra ita. is an important tree species for preventing rainfall-triggered shallow landslides and hydraulic bank erosion in New Zealand. However, the quantification of its spatial root distribution and reinforcement remains challenging. The objective of this study is to calibrate and validate models for the spatial upscaling of root distribution and root reinforcement. The data were collected in a 26-year-old “Tasman” poplar stand at Ballantrae Hill Country Research Station in New Zealand. We assessed root distribution at different distances from the stem of four poplar trees and from eleven soil pits along a transect located in a sparse to densely planting poplar stand. 124 laboratory tensile tests and 66 field pullout tests on roots with diameters up to 0.04 m were carried out to estimate root mechanical properties. The results show that the spatial distribution of roots can be well predicted in trenches of individual tree root systems (R2 = 0.78), whereas it tends to overestimate root distribution when planting density was higher than 200 stems per hectare. The root reinforcement is underestimated within single tree root systems (R2 = 0.64), but it performs better for the data along the transect. In conclusion, our study provided a unique and detailed database for quantifying root distribution and reinforcement of poplars on a hillslope. The implementation of these models for the simulation of shallow landslides and hydraulic bank erosion is crucial for identifying hazardous zones and for the prioritization of bio-engineering measures in New Zealand catchments. Results from this study are useful in formulating a general guideline for the planning of bio-engineering measures considering the temporal dynamics of poplar’s growth and their effectiveness in sediment and erosion control.

Transcriptome Sequencing and WGCNA Reveal Key Genes in Response to Leaf Blight in Poplar.

Leaf blight is a fungal disease that mainly affects the growth and development of leaves in plants. To investigate the molecular mechanisms of leaf blight defense in poplar, we performed RNA-Seq and enzyme activity assays on the Populus simonii × Populus nigra leaves inoculated with Alternaria alternate fungus. Through weighted gene co-expression network analysis (WGCNA), we obtained co-expression gene modules significantly associated with SOD and POD activities, containing 183 and 275 genes, respectively. We then constructed a co-expression network of poplar genes related to leaf blight resistance based on weight values. Additionally, we identified hub transcription factors (TFs) and structural genes in the network. The network was dominated by 15 TFs, and four out of them, including ATWRKY75, ANAC062, ATMYB23 and ATEBP, had high connectivity in the network, which might play important functions in leaf blight defense. In addition, GO enrichment analysis revealed a total of 44 structural genes involved in biotic stress, resistance, cell wall and immune-related biological processes in the network. Among them, there were 16 highly linked structural genes in the central part, which may be directly involved in poplar resistance to leaf blight. The study explores key genes associated with leaf blight defense in poplar, which further gains an understanding of the molecular mechanisms of biotic stress response in plants.

Ecology and distribution of the European Roller &lt;i&gt;Coracias garrulus&lt;/i&gt; in a recently recolonized area of Northern Italy

This study reports the first data on the ecology and distribution patterns of a population of Eurasian Roller Coracias garrulus breeding in the province of Alessandria in northwestern Italy. The research was conducted between 2017 and 2021. 13 pairs were found, 12 of which were confirmed to be breeding. The species primarily chose to nest in natural cavities in White poplar Populus alba, with nesting observed to a lesser extent in Black poplar Populus nigra, Turkey Oak Quercus cerris and in one case sandy river banks. The home range of each pair is mostly within pluriannual stable meadows and arable crops; on average it extends over 0,92 km2 with values that seems to oscillate according to the degree of fragmentation and isolation of patches of stable meadows: this can be explained by the lower availability of arthropods (consisting mostly of Orthoptera) found in mosaics of alternating meadows interspersed with annual crops. In such conditions, a low density of pairs was observed, along with an increase in territorial boundaries and greater distance between the nests. In the sectors characterised by large, multi-annual stable meadows, with more diverse and abundant entomofauna, supporting a higher number of breeding pairs, a significant contraction of home ranges is observed, with an increased concentration of nesting sites, and higher intraspecific tolerance. Between 2019 and 2021 a total of 17 artificial nest boxes were installed, 3 of which have been successfully occupied. Given the continuous anthropogenic transformation these territories are regularly facing, sometimes subtracting potential nesting or feeding sites due to crop rotation, coppicing, ex-novo construction of ground solar panel systems on agricultural land, etc., in order to protect and conserve this population of European Roller, it is desirable to put in place a greater number of artificial nest structures together with monitoring aimed at protecting the biodiversity of the territory.

Comparative analysis of bioactive compounds and antioxidant capacity of selected plants as phytogenic feed additives for poultry nutrition

Abstract The paper investigated the phytochemical content and antioxidant activity of poplar buds (Populus nigra L.), turmeric (Curcuma longa) and ginger (Zingiber officinale) extracts. Proximate composition, total polyphenols, ß-carotene, vitamin E, minerals and antioxidant capacity were tested for all selected plants. The proximate analysis of selected plants showed that poplar buds had a higher content of crude protein, fat and fiber than turmeric and ginger. The extract of poplar buds had a significantly higher content of total polyphenols (87.20 mg of gallic acid/g) and vitamin E (210.53 μg/g) than in the extract of turmeric and ginger. The polyphenol content was found to be in the order: poplar buds&gt;turmeric&gt; ginger. The beta carotene content was significantly higher in poplar buds (2.99 μg/g) than in turmeric (1.67 μg/g). Regarding mineral content, turmeric showed the highest content in iron and copper; ginger showed the highest content in manganese and poplar buds had the highest content in zinc. Moreover, poplar buds possessed the highest antioxidant capacity both on vitamin C and E calibration curve, evidencing the rich content in such antioxidants. Therefore, based on the valuable nutritional composition confirmed through this study, poplar buds, turmeric and ginger can be recommended as phytogenic feed additives for poultry nutrition.

Different photorespiratory mechanisms in conifer leaves, where peroxisomes have intrinsically low catalase activity.

Photorespiration is an essential metabolic mechanism associated with photosynthesis; however, little is known about the photorespiratory pathway of conifer gymnosperms. Metabolite analyses of the leaves of 27 tree species showed that the mean glycerate content in conifer leaves was lower than that in angiosperm leaves. We performed experiments where [13 C]-serine was fed to detached shoots of a conifer (Cryptomeria japonica), via the transpiration stream, and compared the labeling patterns of photorespiratory metabolites with those of an angiosperm tree (Populus nigra), because glycerate is produced from serine via hydroxypyruvate in peroxisomes. In P. nigra, hydroxypyruvate, glycerate and glycine were labeled with 13 C, whereas in C. japonica, glycolate and a non-canonical photorespiratory metabolite, formate, were also labeled, suggesting that an H2 O2 -mediated non-enzymatic decarboxylation (NED) reaction occurs in C. japonica. We analyzed changes in the metabolite contents of leaves kept in the dark and leaves exposed to illuminated photorespiration-promoting conditions: a positive relationship between formate and serine levels in C. japonica implied that the active C1 -metabolism pathway synthesizes serine from formate. Leaf gas exchange analyses revealed that CO2 produced through NED was recaptured by chloroplasts. Database analysis of the peroxisomal targeting signal motifs of an H2 O2 -scavenging enzyme, catalase, derived from various species, including nine coniferous species, as well as analyses of peroxisomal fractions isolated from C. japonica and P. nigra leaves indicated that conifer peroxisomes had less catalase activity. These results suggest that NED and the subsequent C1 metabolism are involved in the photorespiratory pathway of conifer leaves, where peroxisomes have intrinsically low catalase activity.

Laisk measurements in the nonsteady state: Tests in plants exposed to warming and variable CO2 concentrations.

Light respiration (RL) is an important component of plant carbon balance and a key parameter in photosynthesis models. RL is often measured using the Laisk method, a gas exchange technique that is traditionally employed under steady-state conditions. However, a nonsteady-state dynamic assimilation technique (DAT) may allow for more rapid Laisk measurements. In 2 studies, we examined the efficacy of DAT for estimating RL and the parameter Ci* (the intercellular CO2 concentration where Rubisco's oxygenation velocity is twice its carboxylation velocity), which is also derived from the Laisk technique. In the first study, we compared DAT and steady-state RL and Ci* estimates in paper birch (Betula papyrifera) growing under control and elevated temperature and CO2 concentrations. In the second, we compared DAT-estimated RL and Ci* in hybrid poplar (Populus nigra L. × P. maximowiczii A. Henry "NM6") exposed to high or low CO2 concentration pre-treatments. The DAT and steady-state methods provided similar RL estimates in B. papyrifera, and we found little acclimation of RL to temperature or CO2; however, Ci* was higher when measured with DAT compared to steady-state methods. These Ci* differences were amplified by the high or low CO2 pre-treatments. We propose that changes in the export of glycine from photorespiration may explain these apparent differences in Ci*.

Host Plant Mediated Differences in Papilio rutulus Lucas Larval Growth (Papilionidae)

Average development times differed significantly among the test plants and ranged from 27.9 days on Populus nigra to 61.5 days on Ligustrum japonicum. Average pupal mass differed significantly among the test plants and varied from 1330 mg on Prunus serotina to 740 mg on Fraxinus latifolia. There was a significant negative relationship between developmental time and percent larval survival and a significant positive relationship between larval survival and pupal mass. Fast larval development on a plant meant higher survival and heavier pupae. The growth rate of Papilio rutulus larvae varied from a high of 0.256 mg/day on Populus nigra to a low of 0.143 mg/day on Populus alba and 0.126 mg/day on Alnus tenuifolia. The larvae were able to extend their development time on some plants like Alnus tenuifolia and Prunus ilicifolia to produce heavier pupae. Biochemical flexibility in larval survival, developmental time and pupal mass allow P. rutulus larvae to utilize a wide variety of native and introduced plants and to colonize large areas in California with few to no native Populus or Salix hosts including urban areas with extensive plantings of ornamental plants and scattered individual apple and stone fruit trees, and the 651,000+ hectares of commercial California almond, stone fruit and apples. Selection of the host plants with the fastest development times allows P. rutulus to survive at high altitude areas in which there are otherwise too few heat units to allow their offspring to attain the pupal stage and overwinter.