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Among biotic and abiotic stresses, the most restrictive for plant distribution is salt stress, where different concentrations might exert harmful effects on seed germination. Recently, nanomaterials were used successfully to mitigate these stresses, indicating that plants may be able to develop normally in adverse conditions. The aim of this study was to examine the effects of graphene oxide (GO) on the germination of Persian clover seedlings under salt stress conditions. Following sown on substrate paper, seeds were tested after exposure to different concentrations of graphene oxide (0, 125, 250, or 500 mg L-1 GO), sodium chloride (0; -0.1; -0.2; -0.3, or -0.4 MPa NaCl) and/or GO + salt concomitantly, and then stored for 7 days in a germination chamber at 20°C in the presence of light. Seed germination and growth parameters of seedlings were determined. Graphene oxide demonstrated protective effect against salt stress as evident by no marked adverse effects on seed germination where GO blocked the salt-induced reduction in germination. The results obtained provide references for the safe application of nanomaterials and emphasize the significance of GO as a promising material for reducing the toxicity of salts in agriculture. [ABSTRACT FROM AUTHOR]

Floating treatment wetlands (FTWs) are a cost-effective ecological engineering tool for the restoration of polluted water bodies. The aims of this work were to evaluate the removal of Cr(III) and Cr(VI) by FTWs using Typha domingensis, and to assess Cr accumulation and distribution in plant tissues and sediment. Treatments were 5 and 10 mg L−1 of Cr(III), and 5 and 10 mg L−1 of Cr(VI), with and without FTWs, and biological control (BC) with FTW without Cr addition. Both Cr species were efficiently removed from water in all treatments (Cr removal > 80%). Cr concentration in sediments of treatment without FTWs was significantly higher than in sediments of treatments with FTWs, indicating that T. domingensis was directly involved in Cr removal. In sediment, Cr was mainly bound to the organic matter in all treatments with a low risk of future release under FTW conditions. T. domingensis demonstrated tolerance to both Cr species at 5 and 10 mg L−1 with Cr accumulated mainly in the roots in all treatments. The use of FTWs planted with T. domingensis is a suitable tool to remediate water bodies contaminated with Cr. This study evaluates the removal efficiency of Cr(III) and Cr(V) in Floating Treatment Wetlands planted with Typha domingensis in greenhouse experiments. Cr accumulation and distribution in plant tissues and different sediment fractions were also assessed [ABSTRACT FROM AUTHOR]

Three species of the rust fungus genus Blastospora, Bl. betulae, Bl. itoana, and Bl. smilacis, have been reported in East Asia. Although their morphological characteristics and life cycles have been investigated, their phylogenetic positions have not been clarified sufficiently. Phylogenetic analysis showed that these three species were included into Zaghouaniaceae of Pucciniales. However, Bl. betulae was phylogenetically distinct from Bl. itoana and Bl. smilacis and different from other genera. Based on this result, and applying recent International Code of Nomenclature decisions/recommendations/requirements, Botryosorus, gen. nov., and Bo. deformans,, comb. nov., were applied for Bl. betulae. Two new combinations, Bl. radiata for Bl. itoana and Bl. makinoi for Bl. smilacis, were also applied. Their host plants and distribution were described based on literature records. Zaghouania yunnanensis, comb. nov., was proposed for Cystopsora yunnanensis as a result of this analysis. [ABSTRACT FROM AUTHOR]

Saudi Arabia diverse landforms include saltmarshes, sand dunes, desert plains, desert pavements, ancient lava fields, and mountains. Climate is influenced by winter Polar and summer Tropical Continental air masses. Tropical Maritime air affects southwestern regions during summer. Climate depends also on location and altitude with hot humid coastal areas, hot dry deserts, hyper-arid desert pavements and lava fields, and temperate mountainous regions. Climate exhibits spatiotemporal patterns reflecting north-south gradients of temperature, rainfall, evapotranspiration, and aridity. Vast latitudinal range and steep altitudinal gradient create temperature variations, affect rainfall seasonality and distribution, and influence dry season duration. Distribution of plant communities and species reflects multitudinous interactions between climate and plant traits, physiology, and chorology. Species exhibiting C3 photosynthesis inhabit cool northern regions and temperate southwestern mountains, species with C4 photosynthesis inhabit hot low-lying regions, and arido-active succulents with crassulacean acid metabolism dominate hyper-arid desert pavements and lava fields. Plant distribution also relates to species chorology with Euro-Siberian, Irano-Turanian, and Mediterranean chorotypes dominating cool northern regions and temperate southwestern mountains, while Saharo-Sindian, Sudano-Zambezian, and Tropical chorotypes dominating hot southern regions. Plant communities and species occurring in different habitats are described in relation to their traits, physiology, and chorology. Nature reserves and phytodiversity hotspots are considered with special reference to endemic, rare, endangered, and invasive species. An environmental perspective is also given in relation to anthropogenic pressures and positive directives of Saudi Vision 2030. [ABSTRACT FROM AUTHOR]

Four shrub species, including the newly described Pachystegia hesperia Heenan & Molloy, are recognised in Pachystegia Cheeseman, a genus endemic to southern Marlborough and northern Canterbury, South Island, New Zealand. Pachystegia hesperia is distinguished by its compact and low statured growth habit, obovate to elliptic-oblong leaves with the adaxial surface reticulate with distinctive primary and secondary veins, a short peduncle and narrow capitula, smaller and fewer ray petals and fewer disc florets. It was previously known by the tagnames P. "B" or P. "Lowry". Pachystegia hesperia has a western and inland distribution comprising Lowry Peaks Range, Amuri Range, and southern parts of Inland and Seaward Kaikōura Ranges. The previously recognised P. insignis (Hook.f.) Cheeseman, P. minor (Cheeseman) Molloy and P. rufa Molloy are retained. Pachystegia insignis has the most widespread distribution and includes plants referred to the tagnames P. "A" or P. "Coast" and is naturally variable in leaf shape, capitula diameter and the presence and number of leafy bracts on the peduncle. Pachystegia minor is restricted to coastal and lowland habitats between Puhi Puhi and Waiau Toa / Clarence Rivers and includes plants from Ōhau Point (Marlborough) previously known by the tagname P. "C var. ii" or P. "Ōhau Point". It is distinguished by rhomboid to obovate leaves, narrow capitula and in having the fewest florets. Pachystegia rufa is distinguished by reddish trichomes on the leaves, stems and infloresences and has a restricted distribution in Haldon Hills, Marlborough. The widespread P. insignis hybridises with P. minor and P. rufa. Typification, distribution, habitats and conservation status are presented for each species. [ABSTRACT FROM AUTHOR]

Annona muricata L. (soursop fruit) is a seasonal plant with bio-geographical distribution in tropical and subtropical climates. This study evaluated the proximate, phenolic, and antioxidant properties of different parts of soursop fruit. The influence of oven and solar drying on phenolic and antioxidant activities of extracts (pulp, seed, and peel) were assessed. Proximate analysis on different parts of the soursop fruit showed the pulp to have high carbohydrate (32.9% ± 0.3) and moisture (19.1% ± 1.0). The seeds however contained higher crude fat (37.5% ± 1.2) and protein (25.0% ± 0.1) contents. Total phenolic content of the seeds (8.7 mgGAE g−1 ± 0.1) was higher than that of the pulp and the peel (8.6 mgGAE g−1 ± 0.1). The solar-dried fruit parts demonstrated superior antioxidant activity to the oven-dried parts. Extracts from the solar-dried soursop fruit samples, especially the seed, can serve as useful therapeutic ingredient for diet supplementation and could also be exploited for its high oil and protein contents. [ABSTRACT FROM AUTHOR]

Freezing injury is a major environmental limiting factor affecting plant yield and geographical distribution. Little is known about the regulation of phenylpropanoid metabolism during freezing (FT) and post-freezing recovery (FR). Dendrobium officinale is a valuable medicinal plant and hypersensitive to low temperature, especially freezing in winter. Here, we used metabolomics and transcriptomics analyses to reveal the regulation of of phenylpropanoid metabolism during FT and FR in D. officinale. Most anthocyanin and flavonol significantly increased during FR, including quercetin 3-O-glucoside (Q3G) and cyanidin 3-O-sophoroside (C3S) increased 104.6-fold and 66.8-fold in FR vs. CK. Transcriptomics analyses revealed the expression levels of flavonoid 3′- hydroxylase (F3'H) and flavonol synthase (FLS), which were related to an increase in quercetin derivatives. Six phytohormone-related GO terms were enriched during FT and FR. Four genes were significantly affected by FT and FR, including MYB97, MYB39, fructosyltransferase, and zinc finger transcript factor. Four GA response-related genes, 2-oxoglutarate-dependent dioxygenases, were specially induced during freezing stress. Moreover, jasmonic acid (JA) and salicylic acid (SA) were significantly increased during FT, and only SA decreased during FR. This study provided understanding of phenylpropanoid metabolism under freezing stress and will be useful for enhancing freezing tolerance via molecular breeding in D. officinale. [ABSTRACT FROM AUTHOR]

Everywhere, typical network systems are challenging two opposite situations, mainly caused by suppliers and consumers. The provision of new power quality resources and an increase in electricity consumption are the main problems in satisfying the daily need and the rising number of critical base loads. Because of the quick and unforeseen increase in consumers and failure to construct new micro-energy power plants in distribution systems in general, optimal control should be implemented to assure the distribution system's proper operation. The application of adequate computational load shedding techniques is necessary for this approach. This paper reviews microgrids' work, a considerable number of computational intelligence methods, and different classes of load shedding techniques applied to date in the distribution systems. A conclusion has been drawn given several unforeseen blackout problems occurring in major electrical distribution companies worldwide. The maximum use must be made of renewable energy resources, mainly when there are load shedding and blackout problems. [ABSTRACT FROM AUTHOR]

Recent bryological research in Portugal has revealed the occurrence of a little-known segregate of the Riccia sorocarpa group, representing the first record for mainland Portugal and the Azores of Riccia sorocarpa Bisch. subsp. erythrophora R.M.Schust. ex Konstant. & L.Söderstr. New data are presented on the taxonomy and phytogeography of this globally rare taxon. A revision of approximately 200 samples of Riccia sorocarpa s.l. from selected Portuguese herbaria, together with some recent field collections, was carried out, based on the results of light and scanning electron microscopy. Our findings confirm that Riccia sorocarpa subsp. erythrophora is a distinct subspecies, and show that morphological differences of the thallus, primarily the violet-red purple bases of the ventral scales, are the most important characters for its delimitation. Scanning electron micrographs of spores of this taxon are presented for the first time. Phytogeographically, our data significantly extend the known distribution of the subspecies. [ABSTRACT FROM AUTHOR]

We report the results of an international bryological expedition to the Khamar-Daban mountain range in Russian southern Siberia. The novel approach of integrative floristics is introduced here as a method of surveying the flora of a region by using a combination of morphological and molecular evidence to identify and verify unexpected findings. We show that use of this approach can deliver a high level of credibility in cases in which direct molecular comparison is possible or the relevant data can be easily obtained from reliable studies informing recent treatments. Integrative floristics can also be used to identify potential taxonomic problems requiring further study. Conventional identification methods based on plant anatomy and morphology were supplemented with molecular barcoding (nuclear ITS, plastid trnL–trnF, rps4 and atpB–rbcL regions) of specimens that either did not fit existing morphological concepts perfectly or for which records were unexpected based on previously established phytogeographical patterns. In total, we recorded ca 380 species of mosses and ca 150 species of liverworts from five localities on the northern slopes of the Khamar-Daban range. Such floristic richness indicates a hotspot of bryophyte diversity with a remarkably high proportion of suboceanic species, such as Brachydontium trichodes (F.Weber) Milde, Herzogiella striatella (Brid.) Z.Iwats. and Racomitrium macounii subsp. alpinum (E.Lawton) Frisvoll. Nearly 20% of specimens were identified or checked using DNA barcoding. This approach showed the presence of previously unrecorded species in a number of genera, including Didymodon, Neckera and Pseudohygrohypnum. [ABSTRACT FROM AUTHOR]

Mountain areas are very often considered to be biodiversity hotspots. Rocks are one of the most unique habitats and serve as a suitable biotope for many endemic and specialized plant species. Here we present the results of the vegetation studies conducted in central and eastern Pamir-Alai and the south-western Tian Shan mountains in 2013‒2019. Based on 334 phytosociological relevés we propose a synopsis of the rock communities of the montane and colline zones of eastern Middle Asia. As a result of our research, we distinguish 17 communities defined into five groups of petrophytic vegetation within the Caricion koshewnikowii alliance. We describe 11 new associations: Feruletum bucharicae, Scrophularietum glabellae, Asperulo albiflorae–Kafirniganietum hissaricae, Scutellarietum immaculatae, Campanuletum eugeniae, Silenetum kuschakewiczii, Rosularietum platyphyllae, Spireaetum pilosae, Silenetum lithophilae, Campanuletum albertii, and Rhinactinidietum limoniifoliae. Distinctiveness of environmental conditions together with the species composition of the phytocoenoses within the montane and colline belts of eastern Middle and Central Asia make the investigated vegetation among those with the highest specific diversity and richness of endemisms in the whole area. The main factors that determine the species composition of the investigated vegetation seem to be phytogeography, altitude, bedrock type, and exposition. Supplemental data for this article is available online at https://doi.org/10.1080/11263504.2021.1922531. [ABSTRACT FROM AUTHOR]

The presence of Ni above the permissible limit in agriculture soils poses negative effects on soil health, crop quality, and crop productivity. Surprisingly, the usage of various organic and inorganic amendments can reduce Ni mobility in the soil and its distribution in the crops. A pot experiment was conducted to elucidate the effects of olive pulp biochar (BR), calcite (CAL), and wheat straw (WS), as sole amendments and their mixtures of 50:50 ratio, added to Ni polluted soil on Ni mobility in the soil, Ni immobilization index (Ni − IMi), soil enzymatic activities, Ni distribution in parts of chili plant, Ni translocation factor and bioaccumulation factor in fruit, plant growth parameters and oxidative stress encountered by the plants. Outcomes of this pot experiment revealed that amendments raised soil pH, improved soil enzymatic activities, values of Ni − IMi, while significantly reduced bioavailable Ni fraction in the post-harvest soil. However, the highest activities of acid phosphatase, urease, catalase, and dehydrogenase by 50, 70, 239, and 111%, respectively, improvement in Ni − IMi up to 60% while 60% reduction in the bioavailable Ni fraction was observed in BR + CAL treatment, compared to control was noted. Among all amendments, the top most reduction in Ni concentrations in shoots, roots, fruit, Translocation Factor (TF), and Bioaccumulation Factor (BAF) values of fruit by 72%, 36%, 86%, 72%, and 86%, in BR + CAL treatment, compared to control. Moreover, the plants growing on BR + CAL amended Ni contaminated soil showed the topmost improvement in plant phonological parameters while encountered the least oxidative stress. Such findings refer to the prospective usage of BR + CAL at 50:50 ratio than BR, CAL, WS alone, and BR + WS as well as WS + CAL for reducing Ni mobility in the soil, improving Ni − IMi, soil enzymatic activities, plant phonological and oxidative stress while reducing Ni distribution in plant parts. Novelty statement In this experiment, it was hypothesized that amending Ni polluted soil with olive pulp biochar (BR), CAL, and WS as alone soil amendments and their combinations at 50:50 ratios can reduce Ni bioavailability in soil, Ni distribution in chili plant and oxidative stress encountered by the plants. Moreover, these amendments may improve, soil enzymatic activities, Ni immobilization index, plant phenological traits. Therefore, it was aimed to undertake useful scientific planning and research, to restore and rehabilitate the dwellings, biological resources and to minimize the sufferings of the peoples in nutrient-poor Ni contaminated soils, by improving soil health and chili productivity. [ABSTRACT FROM AUTHOR]

Canola (Brassica napus) is a significant oilseed crop in the world, including in Pakistan. Increases in global temperatures will likely affect future plant species distribution, and could influence the survivability of individual species because of the relationship between temperature, germination and dormancy. The objective of this study was to improve heat tolerance in canola with the foliar application of sulfur. Therefore, a pot study was performed in a growth room at the Institute of Horticultural Sciences, University of Agriculture Faisalabad in 2017-2018 under controlled conditions. Two varieties of canola, i.e., Hyola-401 and 45S42, two levels of foliar sulfur (S0= 0ppm and S1 500ppm) treatments, and two temperature levels (T1=8°C and T2=288°C) were studied. Heat stress was imposed at the time of anthesis (55-60 days after emergence). Collected data indicated that morphological characters such as root shoot length and their fresh and dry weight showed better performance where foliar sulfur was applied either in heat stress as well as in control conditions where no heat stress was imposed. The photosynthetic rate (6.21 m mole CO2 m-2/sec), stomatal conductance (0.12 m mole CO2 m-2/sec) and intercellular CO2 concentration (346.13 m mole CO2 m-2/sec) were improved in sulfur treatments under heat stress conditions while transpiration rate (0.51 mol H2O m-2 s-1) was decreased with foliar application of sulfur. Similarly, yield and yield components (No. of siliques per plant (23), No. of seeds per siliqua (20), 1000 seed weight (3.53 g) and overall yield (2.11 t/ha) increased where foliar sulfur was applied @ 500ppm. Overall results concluded that the foliar application of sulfur may be helpful for plant tolerance against heat stress by improving the physiological attributes and yield characters in canola. Moreover, among the genotype of Brassica napus L, Hyola 401 performed better in comparison with genotype 45S42 where foliar applied sulfur under heat stress conditions. [ABSTRACT FROM AUTHOR]

Shallot is one of the major herbs extensively being used in global cuisine. Shallot, like onion and garlic, is infected by various viruses. Shallot virus X (ShVX) infects shallot and cause significant yield loss. In the present study for the first time, effort has been made to examine the load and distribution of ShVX in various parts of shallot plants. Our study indicates that there is uneven distribution of the virus in the plant which vary with different tissues as well as the age of the plant. Accordingly, choice of tissue and age of the selected tissue was found to be a determining factor in indexing process. It was found that bulb is the most suitable tissue for detection of ShVX followed by young leaf. This study also for the first time proved that ShVX is not a seed borne virus. [ABSTRACT FROM AUTHOR]

Equisetales represents a diverse and abundant group of articulate plants with a wide geographical distribution that had their greatest development in late Palaeozoic and early Mesozoic times. The order is represented by 12 families, composed mostly by extinct families of late Palaeozoic age, with only a unique living family, the Equisetaceae. Here we describe the new equisetalean fossil-genus and species Iberisetum wegeneri gen. nov., sp. nov. from the lower Stephanian C (Gzhelian, Upper Pennsylvanian) of intramontane Douro Basin, in northwestern Portugal. This new fossil taxon represents another endemic species for the Douro Basin. Iberisetum wegeneri consists of a leafy articulated stem that shows a unique combination of macro-morphological features that are common in various fossil-genera of different equisetalean families, and that includes exclusive (autapomorphic) characters. The singular morphology of foliar sheaths of Iberisetum wegeneri represents an evolutionary novelty into the Equisetales and suggests a heliotropic organisation (heliotropism) of the plant during its lifetime. Such functional morphology is the result of an evolutionary adaptation to the climatic and ecological conditions restricted to intramontane environments of Douro Basin. [ABSTRACT FROM AUTHOR]

Staurosaccites, a highly distinctive pollen genus, ranges from the late Anisian (Pelsonian; Middle Triassic) to the Norian, at low to mid latitudes, globally. Here we review the systematic taxonomy and spatial and temporal ranges of Staurosaccites. We provide an emendation to S. tharipatharensis, synonymise S. minutus with the type species S. quadrifidus, and retain the species S. quadrifidus, S. tharipatharensis, S. densus and S. marginalis. Following comparison with morphologically similar pollen and environmental reconstructions of the habitat of its parent plant, we hypothesise that Staurosaccites was produced by a conifer that was likely adapted to warm and humid conditions. Based on occurrences of diagnostic taxa for the Onslow and Ipswich microfloral provinces in the Southern Hemisphere (Staurosaccites, Camerosporites, Enzonalasporites, Infernopollenites and Ovalipollis), we show that these palynofloras were established in the Middle Triassic. Our findings further suggest that, based on the presence of diagnostic taxa in western Laurasia and their absence in eastern Laurasia, western and eastern Laurasia represent different palynofloral provinces in the Middle Triassic. [ABSTRACT FROM AUTHOR]

Neonicotinoid pesticides are widely applied for controlling pests in a variety of agriculture crops. Due to the systemic distribution in plants, neonicotinoid pesticides have been found in nectar and pollen, which are the main source of food for the important pollinator honeybee. The risk of neonicotinoid residues in honeybee products and honeybee has caused great attention since their impacts on the environment, ecology, and food safety issues. These concerns require the accurate and sensitive determination of neonicotinoids and their metabolites in the honeybee products and honeybee. Since the trace residue level of neonicotinoid and the complexity of the samples, analysis of neonicotinoid targets in these important matrices is still a great challenge. The present review provides general overview of analytical methods for the determination of neonicotinoid pesticides and their metabolites in honeybee products and honeybee. [ABSTRACT FROM AUTHOR]