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Trade-offs are crucial for species divergence and reproductive isolation. Trade-offs between investment in growth versus defense against herbivores are implicated in tropical forest diversity. Empirically exploring the role of growth-defense trade-offs in closely related species' reproductive isolation can clarify the eco-evolutionary dynamics through which growth-defense trade-offs contribute to diversity. Costus villosissimus and C. allenii are recently diverged, interfertile, and partially sympatric neotropical understory plant species primarily isolated by divergent habitat adaptation. This divergent adaptation involves differences in growth rate, which may constrain investment in defense. Here, we investigate growth-defense trade-offs and how they relate to the divergent habitat adaptation that isolates these species. We characterize leaf toughness and chemistry, evaluate the feeding preferences of primary beetle herbivores in controlled trials and field-based experiments, and investigate natural herbivory patterns. We find clear trade-offs between growth and defense: slower-growing C. allenii has tougher leaves and higher defensive chemical concentrations than faster-growing C. villosissimus. Costus villosissimus has rapid growth-based drought avoidance, enabling growth in drier habitats with few specialist herbivores. Therefore, growth-defense trade-offs mediate synergistic biotic and abiotic selection, causing the divergent habitat adaptation that prevents most interspecific mating between C. villosissimus and C. allenii. Our findings advance understanding of ecological speciation by highlighting the interplay of biotic and abiotic selection that dictates the outcome of trade-offs.

Summary: Hybridization is increasingly recognized as an important evolutionary process across the tree of life. In many clades, phylogenomic approaches have permitted unparalleled insight into the extent and frequency of hybridization. However, we continue to lack a deep understanding of the factors that limit and shape patterns of hybridization, especially in evolutionary radiations. In this study, we characterized patterns of introgression across Costus (Costaceae), a young evolutionary radiation of tropical understory plants that maintain widespread interfertility despite exhibiting strong prezygotic reproductive isolation.We analyzed a phylogenomic dataset of 756 genes from 54 Costus species using multiple complementary approaches – D‐statistics, gene‐tree‐based tests, and phylogenetic network analyses – to detect and characterize introgression events throughout the evolutionary history of the radiation.Our results identified a moderate number of introgression events, including a particularly ancient, well‐supported event spanning one of the deepest divergences in the clade. Most introgression events occurred between taxa or ancestral lineages that shared the same pollination syndrome (bee‐pollinated or hummingbird‐pollinated).These findings suggest that prezygotic barriers, including pollinator specialization, have been key to the balance between introgression and reproductive isolation in Costus. [ABSTRACT FROM AUTHOR]

Plant leaves receive different light intensities that lead to changes in many of their characteristics, including leaf morphology and anatomy. These changes occur in trees within- and between-crown and this ecophysiological issue has been widely addressed in temperate regions. However, due to increased habitat complexity and species richness, tropical forests may create slightly different light gradients. This study compares these gradients using a tropical plant, Eugenia hiemalis, a high plastic shrub. Leaves were collected from the top and base of the crown of sun-exposed plants (within-crown light gradient) and compared with leaves collected from the middle of crowns, of plants in sunny and shaded sites (between-crown light gradient). The analysis of 25 morphological and anatomical characteristics showed that the between-crown light gradient has a greater influence on leaf responses to light, possibly due to the existence of highly shaded environments in tropical forests compared to surrounding grasslands. Leaves that receive more light have a thicker cuticle and mesophyll and higher stomatal density, leaves at the top of the crown. On the other hand, leaves at the base of the crown and from shaded sites had greater leaf area, leaf dry mass, and specific leaf area. The vertical light gradient that occurs within-crown is weaker than the between-crown gradient, suggesting a great acclimation ability of species both inside and outside tropical forests, such as found in E. hiemalis. [ABSTRACT FROM AUTHOR]

Jaboticaba is a typical tropical plant that blossoms and bears fruit on the tree trunks and branches. The fruits resemble grapes in appearance and texture and are also known as "treegrapes". Currently, research on the genomics of jaboticaba is lacking. In this study, we constructed an integrated, telomere-to-telomere (T2T) gap-free reference genome and two nearly complete haploid genomes, thereby providing a high-quality genomic resource. Furthermore, we unveiled the evolutionary history of several species within the Myrtaceae family, highlighting significant expansions in metabolic pathways such as the citric acid cycle, glycolysis/gluconeogenesis, and phenylpropanoid biosynthesis throughout their evolutionary process. Transcriptome analysis of jaboticaba fruits of different colors revealed that the development of fruit skin color in jaboticaba is associated with the phenylpropanoid and flavonoid biosynthesis pathways, with the flavanone 3-hydroxylase (F3H) gene potentially regulating fruit skin color. Additionally, by constructing the regulatory pathway of the citric acid cycle, we found that low citric acid content is correlated with high expression levels of genes such as thiamin diphosphate (ThDP) and low expression of phosphoenolpyruvate carboxykinase (PEPCK), indicating that PEPCK positively regulates citric acid content. These T2T genomic resources will accelerate jaboticaba pepper genetic improvement and help to understand jaboticaba genome evolution. [ABSTRACT FROM AUTHOR]

Species delimitation remains a challenge worldwide, especially in highly diverse tropical and subtropical regions. Here, we use an integrative approach that combines morphology, phylogenomics, and species distribution modeling (SDM) to clarify the cryptic differentiation within the enigmatic hemiparasitic love vine Cassytha filiformis (Lauraceae) in China and adjacent regions. We generated complete plastid genomes and nuclear ribosomal sequences for diverse samples from across the species range and compared results with previously published plastid data, recovering two well‐supported monophyletic clades. Further, the analysis revealed significant differences in two morphological characters and SDM, indicating distinct environmental factors influencing their distributions. Fossil‐calibrated analyses to estimate the origins and diversification patterns for the cryptic species gave divergence age estimates corresponding to the Oligo‐Miocene; a period of new ecological opportunities associated with the prevailing East Asian monsoon. Multivariate analyses support the conclusion that southern China and adjacent regions have a different, previously unknown, cryptic lineage of C. filiformis. Our study highlights the importance of using multivariate approach to characterize plant species, as well as the significant role that past climatic changes have played in driving speciation in parasitic plants in tropical and subtropical zones. [ABSTRACT FROM AUTHOR]

Extreme heat events are becoming increasingly common, and the short‐term acclimation of photosynthesis will have a large impact on plant performance. Trees in lowland tropical forests, which are hypothesized to have limited abilities to tolerate rising temperatures, may need to rely on short‐term acclimation of their more plastic traits, like photosynthetic thermal tolerance, to persist in the face of increasingly variable climates.Here, we investigated seasonal acclimation of thermal tolerances in plant species of the moist Amazon. Specifically, we measured the photosynthetic thermal tolerances of six common woody Amazonian species at the beginning and at the end of the dry season to determine the species' abilities to acclimate to intra‐annual changes to climate. In addition, we used the natural thermal gradient present at our research site to test the acclimation of individual plants to maximum air temperatures not currently observed elsewhere in the moist lowland Amazon (up to ~43°C).Between seasons, there were significant overall increases in the thermal tolerances of three species (i.e. higher thermal tolerances in the hotter dry season), suggesting that leaf megathermy is prominent in these species. Also, three species acclimated their thermal tolerances to microsite‐level differences in seasonal temperature maxima, suggesting closer fidelity between leaf and air temperatures (i.e. limited homeothermy) for these species.Our results show that some woody species from the moist Amazon can acclimate their thermal tolerances over short time‐scales, although acclimation is likely insufficient to overcome thermal stress during extreme temperature events. Some species may therefore be more sensitive to heatwaves than others, which could impact survival and composition of tropical lowland forests into the future. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

During a survey conducted in autumn 2022 and spring 2023, extensive leaf spots were observed on Aristolochia grandiflora plants in the Botanical Garden "Angelo Rambelli" (Viterbo). To preserve the botanical garden collection and avoid disease spread, morphological and molecular identification of the causal agent were carried out. The results revealed three distinct Colletotrichum species belonging to the Colletotrichum boninense and Colletotrichum orchidearum species complexes, which have never been reported together within the same host and, for two of them, never in Italy. These findings may contribute to further extend the state of the art on leaf anthracnose, as well as provide new insights and molecular data for further phylogenetic studies. [ABSTRACT FROM AUTHOR]

The need to increase yield and enhance the sustainability of crop production systems has led to the development and employment of natural products, such as plant biostimulants. In recent years, a number of reports have researched the effects of biostimulants on plant performance; however, few studies have focused on the mutual application of microbial and/or non-microbial biostimulants. This research, conducted in the framework of the SO.MI.PR.O.N regional project, aimed to investigate the single or mutual application of three biostimulants, a tropical plant extract (PE), a vegetal protein hydrolysate (PH), and Trichoderma atroviride, on 'Creativo' F1 cherry tomato plants cultivated during two growing cycles (2022–2023 and 2023–2024). Our results showed that plants treated with the combination Tricho + PE + PH had statistically significant higher fresh shoot biomass (+64.2%, 1647.0 g plant−1), total fruit production (+37.9%, 1902.5 g plant−1), marketable fruit production (+52.9%, 1778.5 g plant−1), and average weight of marketable fruits (+53.1%, 17.0 g) compared to control plants (untreated plants). Furthermore, biostimulant treatments, especially T. atroviride, variably enhanced cherry tomato fruits' qualitative traits, such as firmness, total soluble solids, ascorbic acid, lycopene, and total polyphenols compared to control plants. Overall, the best combinations to increase tomato fruit qualitative features were PE + PH, Tricho + PE, and Tricho + PH. From an economic point of view, the best treatment for achieving the highest net return was PE. This study underlines that biostimulant features (yield, qualitative aspects, and economic profitability) can be supported through the application of specific biostimulant combinations. [ABSTRACT FROM AUTHOR]

Terrestrial vegetation emits substantial amounts of highly reactive isoprene, significantly impacting atmospheric chemistry and climate change. Both atmospheric carbon dioxide (CO2) concentration and temperature can influence plant isoprene emissions; however, whether these factors have a synergistic effect remains unclear, particularly for tropical/subtropical plants. In this study, we conducted in-situ controlled experiments on Eucalyptus urophylla, a representative tropical/subtropical species, to investigate the seasonal variation in the response of isoprene emissions to CO2 concentrations (ISOP-CO2 response) and to identify potential controlling factors. The results showed that high CO2 exerts a nearly linear inhibitory effect on isoprene emissions, as indicated by the slope of the ISOP-CO2 response curve. This inhibitory effect exhibited evident seasonal changes, with stronger suppression during cooler seasons and weaker suppression during warmer seasons. This finding contrasts with the default ISOP-CO2 response in the MEGAN model, which ignored seasonal variation. Further analysis showed a significant correlation between the slope of the ISOP-CO2 response curve and growth temperature from the past 10 days, indicating that these metrics are effective indicators for predicting seasonal changes. Our findings reveal a synergistic mechanism between temperature and CO2 concentration effects on isoprene emissions. By coupling the effects of growth temperature with the ISOP-CO2 response, this mechanism can be integrated into models to provide more accurate predictions of future isoprene emissions, reducing prediction biases, especially during cooler seasons. [ABSTRACT FROM AUTHOR]

Cinnamomum cassia Presl. is a subtropical plant that is used for food and medicine. Climate change has changed the suitable habitats of medicinal plants, which might have repercussions for the efficacy of herbal remedies. In this study, the potential distribution in each period of Cinnamomum cassia was predicted and the quality in different suitable habitats was evaluated. According to the results, (1) precipitation, temperature, and soil are the primary environmental variables influencing C. cassia distribution. (2) The high-suitable habitats of current climate scenarios were predominantly located in the southern regions (Guangdong and Guangxi etc.) of China, with an area of 706,129.08 km2. Under future climate scenarios, suitable habitats will increasingly move northward, with a greater concentration south of the Yangtze River, particularly in the 2090s SSP585 scenario, the total area of newly extended suitable habitat reaches 312,963.53 km2. (3) HPLC and FTIR, combined with chemometrics, can be effective methods for identifying different suitable habitats of C. cassia. The content of trans-cinnamaldehyde (0.85%) is significantly higher in the high suitability habitat compared to the medium-low suitability habitat (0.30%). Our findings can offer valuable guidance for the identification of suitable C. cassia cultivation areas in China, as well as for the evaluation of C. cassia resource quality and the rational use of resources in different suitable habitats. [ABSTRACT FROM AUTHOR]

The article "Exploring biodiversity of Uruguayan vascular plants through DNA barcoding" published in Frontiers in Genetics on October 15, 2024, discusses the use of DNA barcoding to study the biodiversity of Uruguayan vascular plants. The study aims to address the decline in biodiversity in Uruguay by establishing a DNA barcode national network. By analyzing 171 sequences from four loci for 50 vascular plant species, the researchers identified suitable markers for plant DNA barcoding and contributed to the Uruguayan Barcode of Life Initiative. The study highlights the importance of creating a comprehensive public database for species identification and biodiversity research. [Extracted from the article]

Background and Objectives: Low temperature has a major influence on survival and geographical distribution of plants and as an important environmental factor, it affects plant productivity. Physalis (Physalis peruviana L.) belongs to the Solanaceae family and is a tropical and subtropical plant that is affected by low temperatures at beginning and end of the growing season. These fruits are highly beneficial to human health due to their nutritional and bioactive compounds (antioxidants, vitamins A, B, C, E and K1, flavonoids and carotenoids), so it has gained attention for cultivation worldwide. Amino acids (L-Phenylalanine and cysteine) or selenium play important roles in plant resistance to low temperature. However, the role of L-phenylalanine (Phe) and cysteine (Cys) or selenium (Se) in regulating chilling tolerance and improve fruit quality of physalis is still unknown. In this study, the effects of Phe, Cys and Se on quality and antioxidant capacity of physalis fruit under low-temperature stress were investigated. Materials and Methods: The experiment was conducted in a randomized complete block design with three replicates. The seeds of physalis (Physalis peruviana L.) were sown in seedling trays containing peat moss under optimal conditions of 25±2 °C during the day and 20±2 °C at night. Different concentrations of L-phenylalanine (0.75, 1.5, and 2.5 mM, Phe), L-cysteine (0.25, 0.5, and 0.75 mM, Cys), or sodium selenate (0.25, 0.5, and 1 mg L-1, Se) were sprayed on the seedlings at the 4-5th true leaf stage. Distilled water was used as the control treatment. To induce chilling stress, plants with the basically same growth were transferred to a 4 °C climate chamber for 48 hours. The control group was grown under optimal conditions. After applying the chilling stress, the plants were returned to optimal growth conditions for 24 hours. Plants transplanted to the field and foliar sprayed three times (growth stage, flowering and fruit set stages) with amino acids and Se. After exposed plants to autumn chilling, fruits harvested during calix and fruit color change from green to orange stage, and plant height, yield and the quality characteristics of the fruit including carotenoid content, membrane stability index, titratable acidity, phenolic compounds and antioxidant activity were evaluated. Results: The results showed that low temperature stress significantly decreased fruit yield, carotenoids content and membrane stability index (MSI), and increased titratable acidity, phenols and flavonoids content and phenylalanine ammonia-lyase (PAL), superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities. Foliar spray of Physalis plants with Phe, Cys and Se under cold stress significantly increased plant height, fruit yield, antioxidant enzymes activity, MSI, carotenoids, phenolic compound and TA. The highest value of MSI (38.46 and 36.1) was obtained in fruit of plants treated with Se 0.25 and 0.5 mg L-1 under low temperature condition. The maximum phenol content (8.08 and 7.83 mg L-1) of fruit was observed with application of Phe 0.75 mM and Cys 0.25 mM in plants exposed to cold stress. Also, the highest antioxidant capacity was obtained in plant fruits treated with Phe 0.75 and 1.5 mM (60.8%), Cys 0.25 mM (60.26%) and Se 0.5 mg L-1, respectively under low temperature condition, and the lowest antioxidant capacity (50.5%) was observed in control plant fruits. Conclusion: The results of research showed that the foliar application of Phe, Cys or Se treatments, especially the levels of Phe 0.75 and 1.5 mM and Se 0.5 mg L-1 during seedling and field growing periods caused a significant increase in fruit yield, also increased the activity of antioxidant enzymes, phenolic compounds and the membrane stability index of fruits exposed to autumn cold and led to improvement of fruit quality. [ABSTRACT FROM AUTHOR]

Local adaptation is common in plant species, and knowing whether a population is locally adapted has fundamental and applied relevance. However, local adaptation in tropical plants remains largely less studied, and covering this gap is not simple since reciprocal transplantation – the gold standard for detecting local adaptation – is not feasible for most species. Here, we combined genetic, climatic and phenotypic data to investigate ecotypic differentiation, an important aspect of local adaptation, in coastal and inland populations of the orchid Epidendrum fulgens Brongn., a long‐lived tropical plant for which reciprocal transplantation would not be feasible.We used nine microsatellite markers to estimate genetic divergence between inland and coastal populations. Moreover, occurrence data and climate data were used to test for differences in the realized niche of those populations. Finally, we assessed saturated water content, leaf specific area, height, and stomatal density in common garden and in situ to investigate the effects of ecotypic differentiation and plasticity on the phenotype.Coastal and inland groups' niches do not overlap, the former occupying a wetter and warmer area. However, this differentiation does not seem to be driven by ecotypic differentiation since there was no positive correlation between genetic structure and climate dissimilarity. Moreover, specific leaf area and leaf saturated water content, which are important phenotypic traits related to soil fertility and drought stress, were rather plastic.We conclude that ecotypic differentiation is absent, since phenotypic plasticity is an important mechanism explaining the niche broadness of this species. [ABSTRACT FROM AUTHOR]

Kratom (Mitragyna speciosa) is a psychotropic tropical plant that is used as a traditional remedy in Southeast Asia. It has many medicinal properties and has great potential for clinical applications. Mitragynine and 7-hydroxymitragynine (7-OH) are the important pharmacologically active compounds found in kratom with mitragynine as the major alkaloid found in the leaf. We report the development and validation of a high-performance liquid chromatography-photodiode array method for the determination and quantification of mitragynine from M. speciosa fresh leaf extract. Fresh leaf samples were cryogenically ground and freeze-dried before methanol extraction. Gradient elution was conducted using acetonitrile and ammonium bicarbonate buffer (pH 9.5) at a flow rate of 1 mL min-1. Chromatogram separation was achieved using Kinetex EVO C18 column in a duration of 25 min with MG eluted at 15.75 min. The calibration curves were in a linear relationship with determination coefficients (R2) = 0.99. Mitragynine quantification was calculated based on the calibration curve equation. The precision value (RSD) was less than 2% and accuracy range from 93%-100%. The values for limit of detection (LOD) and limit of quantification (LOQ) were 0.67 µg mL-1 and 1.51 µg mL-1, respectively. This method has been validated and found suitable for the quantification of mitragynine in fresh leaf. We found that freeze-drying during sample preparation from fresh leaf yielded more reliable mitragynine quantification, compared with that of conventional oven-drying method. [ABSTRACT FROM AUTHOR]

Anisomeles malabarica, the commonly called "Malabar catmint" is a wild tropical plant belonging to the family Lamiaceae. Traditionally this plant is used as mosquito repellent, snakebite antidote and to treat fever and gastrointestinal discomfort by the people of South India. It is an important endemic plant used in the indigenous medicine systems of India such as Ayurveda, Siddha, and Unani in various formulations. The rich phytochemistry of A. malabarica includes cembrane terpenes, flavonoids, alkaloids, steroids, flavones, glycosides, and other bioactive compounds contributing for its medicinal potential. Extracts and metabolites of A. malabarica shows wide range of significant pharmacological effects in combating cancer cells through apoptosis, inhibiting viral agents (HPV and SARS-CoV-2), immune regulation, and DNA protection. The phytocompounds of A. malabarica were also reported for anti-malarial, anti-rheumatic, anti-inflammatory, anti-epileptic, anti-diabetic, anti-parasitic activity, and hepatoprotective properties. This systematic review summarizes the therapeutic properties with botanical characteristics, ethnobotany, and phytochemistry of A. malabarica. It also documents the ingrained traditional use of A. malabarica in religious custom in southern states of India. Therefore further exploration of this promising medicinal herb for its metabolites and ethnobotanical records would possibly support the development of modern medicine systems and provides insights for future research. [ABSTRACT FROM AUTHOR]

Plant–hummingbird interactions are considered a classic example of coevolution, a process in which mutually dependent species influence each other's evolution. Plants depend on hummingbirds for pollination, whereas hummingbirds rely on nectar for food. As a step towards understanding coevolution, this review focuses on the macroevolutionary consequences of plant–hummingbird interactions, a relatively underexplored area in the current literature. We synthesize prior studies, illustrating the origins and dynamics of hummingbird pollination across different angiosperm clades previously pollinated by insects (mostly bees), bats, and passerine birds. In some cases, the crown age of hummingbirds pre‐dates the plants they pollinate. In other cases, plant groups transitioned to hummingbird pollination early in the establishment of this bird group in the Americas, with the build‐up of both diversities coinciding temporally, and hence suggesting co‐diversification. Determining what triggers shifts to and away from hummingbird pollination remains a major open challenge. The impact of hummingbirds on plant diversification is complex, with many tropical plant lineages experiencing increased diversification after acquiring flowers that attract hummingbirds, and others experiencing no change or even a decrease in diversification rates. This mixed evidence suggests that other extrinsic or intrinsic factors, such as local climate and isolation, are important covariables driving the diversification of plants adapted to hummingbird pollination. To guide future studies, we discuss the mechanisms and contexts under which hummingbirds, as a clade and as individual species (e.g. traits, foraging behaviour, degree of specialization), could influence plant evolution. We conclude by commenting on how macroevolutionary signals of the mutualism could relate to coevolution, highlighting the unbalanced focus on the plant side of the interaction, and advocating for the use of species‐level interaction data in macroevolutionary studies. [ABSTRACT FROM AUTHOR]

Invasive plants disrupt ecosystems by influencing species interactions, aiding co-invader integration, and worsening competition for native plants. Successful forest invasive species management relies on grasping these interaction patterns at the community level. This study aims to assess the community attributes of invasive plants in tropical forests of Northeast India, examining their dominance in various habitats, elucidating their influence at the community level and some species-specific effects on associated co-invaders and non-invasive groups. The present investigation recorded 101 invasive plant species mostly of neotropical origin, comprising of grasses, sedges, forbs, shrubs, trees, and vines. The findings revealed both positive and negative effects of invasive species richness and their percentage at community level and throughout different habitats. However, the presence of dominant invasive species caused a substantial decrease in species diversity of plant community in the study area, depicting a significant negative association with the non-invasive group and a notable positive association with the co-invasive group. These findings offer valuable insights by specifying the community-level impacts of exotic invaders on the natural plant population which will be very helpful in devising effective management plans to counter biotic invasion in the biodiversity rich tropical forested landscapes. [ABSTRACT FROM AUTHOR]

The morphological characters of Southeast Asia's indigenous Peperomia species are very similar, especially in their flower structures. The flowers are simple, hermaphrodite and lack a perianth. Therefore, many species are hard to distinguish using morphological characters alone. Here, we apply chemometric data for species identification and classification, gathered using multiwavelength detection combined with the colour scale High-Performance Thin-Layer Chromatography (HPTLC) fingerprinting procedure and chemical compounds determined by Gas Chromatography–Mass Spectrometry (GC-MS). Fourteen taxa were investigated using hexane, ethyl acetate and ethanol solvent extractions. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used with the colour scale fingerprints to classify the Peperomia species. The PCA and HCA using the chromatogram profile from hexane divided the taxa into six groups compared to the profile from ethyl acetate and ethanol, which each detected seven groups. The chromatogram from the combined dataset of all three solvents can differentiate all the species. The GC-MS data detected a total of 40 compounds from the hexane extract, and these differed among Peperomia species. This approach based on HPTLC fingerprinting and GC-MS analysis can therefore be used as a tool for authentication and identification studies of Peperomia species. [ABSTRACT FROM AUTHOR]

Storage of desiccation-tolerant seeds is one of the most effective germplasm conservation strategies; however, various species from tropical and subtropical humid forests have seeds that are sensitive to desiccation, recalcitrant seeds, making conservation a challenge. Recalcitrant seeds deteriorate during storage due to high respiration rates and metabolic activity, and protocols employing osmoprotective solutions aim to minimize those effects to maintain seed viability for a longer period. Hancornia speciosa, a fruit tree considered a priority for research in Brazil, is a desiccation-sensitive species of biannual harvest. Thus, the objective of this study was to assess the physiological parameters of viability, vigor, and enzymatic activity of H. speciosa seeds of two harvest seasons, stored in an osmoprotective solution. Germination percentage, water content, electrical conductivity, shoot, root, and seedling length, peroxidase concentration, and heat-resistant protein concentration were all determined for seeds collected during the summer and winter harvests. In addition, gene sequences were explored through gene ontology using Blast analysis to identify the biological and molecular processes associated with enzymatic action during storage. Summer-collected seeds performed better in terms of viability and vigor, with the highest development of shoot, root, and seedling length. The summer-harvest seeds had an initial germination of 80% and maintained a 15% germination rate until 90 days of storage. The seeds collected in the winter had lower initial germination and vigor; however, improved in those parameters during storage in the protective solution, with an increase of 12.5% in germination rate after 90 days. H. speciosa seeds harvested in the summer or winter and stored in the osmoprotective solution remain viable for up to 90 days. The solution has an osmopriming effect on low-vigor seeds, increasing viability and vigor, and the summer-harvest seeds are recommended for storage in the osmoprotective solution. Peroxidase and heat-resistant proteins are active during storage in the solution; the regulation of the expression of these enzymes should be investigated further. [ABSTRACT FROM AUTHOR]

Aquilaria (Thymelaeaceae), a tropical and subtropical plant, is one of the main genera that can produce agarwood. Aquilaria sinensis and Aquilaria yunnanensis are native Chinese tree species, and A. sinensis is China's main agarwood source. Agarwood is a nontimber forest product with high economic and medicinal value. First‐grade agarwood is sold as much as $100 000 per kilogram. There has been little research on the saprobic fungi associated with Aquilaria, with only 11 records having been reported. In the present study, 10 terrestrial saprobic fungi associated with A. sinensis and A. yunnanensis were collected in China. Based on morphological and phylogenetic studies, these 10 collections are introduced herein as one new genus (Aquilariomyces), nine new species – Aquilariomyces aquilariae, Corynespora aquilariae, Melomastia maomingensis, Nigrograna aquilariae, Parathyridariella aquilariae, Peroneutypa maomingensis, Phaeoseptum aquilariae, Pseudothyridariella aquilariae, and Triangularia aquilariae, and one known species (Camarographium clematidis). Descriptions, illustrations of morphological characteristics, photo plates, phylogenetic trees, and the results of a pairwise homoplasy index test (PHI) test results are provided. [ABSTRACT FROM AUTHOR]

Using population genomics and molecular biological methods, a recent study reveals the molecular mechanisms of vivipary in mangroves, a term designating all woody plants of the tropical intertidal zones. [ABSTRACT FROM AUTHOR]

This study explores the role of floral volatile organic compounds (FVOCs) in insect behavior, focusing on Aquilaria sinensis (AS), a valuable tropical plant threatened by Heortia vitessoides Moore. Despite H. vitessoides' attraction to AS and non-host plants like Elaeocarpus decipiens (ED) and Dalbergia odorifera (DO), little is known about their chemical interactions. FVOCs from these plants were analyzed at 9:00 and 18:00 using GC×GC-QTOF-MS and HS-SPME. The results showed that ED exhibiting the highest concentration (92.340 ng/mg), followed by DO (75.167 ng/mg) and AS (64.450 ng/mg). Through GC-EAD and EAG, a total of 11 FVOC compounds with electrophysiological activates were identified. These compounds, except linalool, showed dose-dependent responses. Y-Tube bioassays confirmed phenylethyl alcohol or the mixture of EAD-active compounds produced positive chemotactic responses in both males and females. FVOCs have the potential to be used as a natural and sustainable alternative to chemical insecticides in pest control. [ABSTRACT FROM AUTHOR]

Psidium guajava: is a tropical tree that is widely used in traditional medicine, especially for treating diarrhea. While P. guajava has been the subject of numerous reviews, none have specifically examined its ethnobotany, pharmacology, and phytochemistry in relation to its antidiarrheal activity. This review aims to summarize the evidence of effectiveness and safety of P. guajava in the treatment of diarrhea. Literature searches were conducted through Web of Science, PubMed, and ScienceDirect by using keywords "Psidium guajava" and "diarrhea" in October 2022. A total of 189 studies were included in this review. P. guajava is widely used in traditional medicine in 44 countries. Decoction and oral were the most represented method of preparation and administration, respectively, while leaves represented the most frequently cited part of the plant. Around 27 antidiarrheal or antibacterial compounds have been isolated and identified, including benzophenone glycosides, terpenes, polysaccharides, phenols, and flavonoids. This article presents ethnobotanical and pharmacological evidence for the efficacy of P. guajava leaves in the treatment of diarrhea and provides reference information for further investigation of this plant. However, despite the large number of publications on the topic, there are still some questions to answer: are quercetin and its glycosides the only ones to act as antidiarrheal agents? What is the mechanism of action of P. guajava antidiarrheal compounds? are the use of guava leaves safe in all types of populations including children, and at what dosage? To answer these questions, more complete phytochemical studies and systematic clinical trials are needed. [ABSTRACT FROM AUTHOR]

Silver-leaved Zingiber group (Zingiberaceae) previously known only from Borneo was now appended with a new species from Taman Negeri Rompin, Pahang, Peninsular Malaysia -- marking the first record of this group outside the Borneo island. The new species, Zingiber zulkifliana Tan, Besi & Go was described, illustrated, and compared to its closest relatives in this study. An artificial key to differentiate the species of the silver-leaved Zingiber was also provided. [ABSTRACT FROM AUTHOR]

Turkey berry, also known as Solanum torvum Swartz, is native to Africa, Asia and South America. This tropical plant of the family Solanaceae has versatile uses in both food and medicine in tropical and subtropical countries. It has been employed in traditional medicine all over the world. Chemical composition of this fruit, its pharmacological properties as ascertained through scientific investigations and its clinical applications are discussed. S. torvum contains numerous important metabolites such as saponins steroids and flavonoids, which function as antioxidants, antifungal, antidiabetic, anticancer, antiulcer, antianxiety and immunomodulators. Various notable roles in ethnomedicinal uses and approaches as a traditional medicinal herb. These have been found in large amounts and have various functions, including antioxidant properties against cardiovascular diseases and immune-modulating activities. Notably leaves extracts, fruits etc. have beneficial therapeutic traits. For a long time now, "Solanum torvum" has been used to treat numerous conditions such as fever, wounds, etc. Research backs up these traditional uses by pointing out the plant's blood pressure management, kidney protection nature, and immune-boosting capabilities. The review summarizes the importance of ethnobotany, its chemical composition, and the scientifically proven pharmacological activities of S. torvum. [ABSTRACT FROM AUTHOR]

Fruit and seed morphometry was studied across 1070 plant species belonging to 140 families from 27 contrasting plant communities. The main objectives were to identify allometric relationships and describe the frequency distributions of the weights and sizes of fruits and seeds across plant species, regardless of any qualitative attribute or community type. The frequency distributions of 12 morphometric variables were then determined. Pearson correlations were used to describe associations between quantitative attributes and estimate the slopes of the lines (allometric coefficients) obtained. In general, small fruits and seeds (<1 cm) prevailed in the sample examined. The frequency distributions of the weight and size parameters of the fruits and seeds were bell‐shaped, with the exception of the number of seeds per fruit, which was skewed to the right. The highest allometric coefficients were found between the dry weights and sizes of the fruits and seeds, suggesting that these traits are mutually supporting. The cost of seed packaging per fruit, or the pericarp/seed ratio, tended to decrease with increasing investment in progeny, and the number of seeds per fruit decreased with an increase in seed weight. The significant associations between the fruit shape indexes and the morphometric attributes show that the shape of fruits is related to their size and weight. The highest allometric coefficients were found between the dry weights and sizes of the fruits and seeds. Fruit and seed size can predict their biomass and vice versa. There is a close relationship between fruit biomass values and their components (seeds and pericarp). Most species invest more biomass in pericarp (protection and dispersal) compared with the investment in progeny (seed per fruit). The sample examined could be influenced taxonomically along with selective pressures that favour the reproductive economy of the species and suggest that morphometric traits have evolved in coordination. [ABSTRACT FROM AUTHOR]

Indoor greening is becoming popular because it provides many benefits for people. However, plant selection for indoor greening is limited to shade-tolerant tropical plants internationally, and little research has been performed to expand the use of native herb plant species. The aim of this research was to study growth characteristics of Japanese native herbs under common light intensity regimes in office buildings. Eight species of Japanese native herbs (Acorus gramineus, Cameilla sinensis, Farfugium japonicum, Gynostemma pentaphyllum, Perilla frutescens var. crispa f. viridis, Petasites japonicus, Sasa veitchii, and Saxifraga stolonifera) were examined in an open growth chamber with light-emitting diode light tape under three light intensities [photosynthetic photon flux densities of 3 µmol⋅m-2⋅s-1 (250 lx), 6 µmol⋅m-2⋅s-1 (500 lx), and 12 µmol⋅m-2⋅s-1 (750 lx)] from 8 AM to 10 PM every day from Jun 2021 to Oct 2021 in an office. Farfugium japonicum and Saxifraga stolonifera were as shade-tolerant as typical tropical plants and grew well under all light intensities. Sasa veitchii performed well under high and medium light intensity. The other plant species require supplemental lightning to achieve sufficient growth indoors. [ABSTRACT FROM AUTHOR]

Fire-adaptive traits in plants of tropical and subtropical grassy ecosystems have been the subject of considerable global research, but only recently studied in pyrogenic Florida subtropical grasslands. Plant growth forms, belowground organs, and post-fire recovery strategies were studied for 198 grassland specialists in peninsular Florida. Community types (dry-mesic, mesic, wet-mesic, and wet) were sampled with 1m2 plots along the edaphic-hydrologic gradient and the association between these variables and fire-related plant traits was tested using fourth-corner analysis. Caulescent herbs (43), cespitose graminoids (27), and rosette herbs (31) are the most common growth forms among species sampled. Plants with epigeogenous and hypogeogenous rhizomes dominate the sample plots, including matrix graminoids, shrub geoxyles, and an acaulescent rhizomatous fire-resilient palm (Serenoa repens). Most species (163; 82%) exhibit resprouting, including 30 facultative resprouters and 133 obligate resprouters. All woody rhizomatous species are obligate resprouters, and 35 ephemeral herbaceous species are obligate reseeders. Community type was a better predictor of species abundances than hydrology, however, hydrology was significantly associated with species traits measured, particularly rhizome texture, with woody rhizomes prevalent in all but the wet sites. Belowground organs (xylopodia, geoxylic suffructices) and growth form were associated with frequent fire and phylogeny, suggesting fire regime as a driver of community phylogenetic diversity. Persistence, rapid resilience and co-occurrence of geoxyles align Florida subtropical grasslands with other global geoxyle grasslands. The old-growth, pyrogenic grassy ecosystems of peninsular Florida are the center of geoxyle diversification on the southeastern US coastal plain. [ABSTRACT FROM AUTHOR]

Taro is a tropical plant and an underutilized root crop that has a good source of carbohydrate. Taro tuber contains 70%–80% of starch on dry basis. This review highlights the extraction of taro starch, latest advancements in the modification such as physical, chemical and enzymatic modification of taro starch. Furthermore, after modification of taro starch, molecular weight and amylopectin branch chain length distribution, granular shape, percentage crystallinity, swelling and solubilization, pasting and thermal properties and in vitro digestibility of taro starch were significantly affected. Additionally, researchers have explored novel methods to modify the physicochemical characteristics of taro starch, enhancing its functionality as a thickening, gelling, and stabilizing agent in various food formulations. However, fabrication of nanoparticles from taro starch was also studies. Various health benefits of taro starch have been reported in this study. One significant health benefit of taro starch is its potential to improve blood sugar management. Furthermore, the versatility of taro starch in food applications has expanded, ranging from traditional staples to modern convenience foods. Its gluten‐free nature makes it an attractive option for individuals with gluten sensitivity or celiac disease. Taro starch is increasingly incorporated into bakery products, snacks, noodles, and as a thickening agent in soups and sauces. The unique sensory attributes and nutritional profile of taro starch contribute to the development of novel, health‐conscious food products that cater to evolving consumer preferences. [ABSTRACT FROM AUTHOR]

Invasive alien plants (IAPs) pose a significant threat to island biodiversity and severely impact ecosystems. Understanding the species–area relationship and environmental determinants of growth forms for IAP species on subtropical islands is crucial for establishing an IAP's early warning mechanism, enhancing island ecological management, and protecting the ecosystems of Fujian and other subtropical islands. The study identified significant species–area relationships for IAPs and different life-form plants (trees, shrubs, and herbs), with slopes of 0.27, 0.16, 0.15, and 0.24, respectively. The small island effect does not apply to all species. Isolation has little effect on species richness, and the IAPs on Fujian islands do not conform to the isolation effect in island biogeography. Landscape factors are the main determinants of IAPs and different life-form species richness, with area, shape index, and perimeter–area ratio being the three primary landscape factors. These environmental factors are closely related to habitat heterogeneity. Besides landscape factors, different life forms respond differently to environmental factors. Climate drives the species richness distribution of shrubs and herbs, while trees are mainly influenced by human activities. Overall, landscape, human disturbance, and climate jointly drive the distribution of IAPs, with landscape factors being the most significant. [ABSTRACT FROM AUTHOR]

AbstractLitsea costalis is a well-known medicinal plant in tropical and subtropical areas. Four significant flavonoids were extracted and characterized from the plant leaf extract. One component was discovered for the first time in flavonoid chemistry, flavan-4-ol, (3′, 4′-methylenedioxy-5,7-dimethoxy chroman-4-ol). Three flavonoids were discovered for the first time in this plant. The detected products are (+)-pinostrobin, (+)-onysilin, and (+)-pinocembrin. The fourth component was characterized for the first time in this plant and introduced in flavonoid chemistry. The extracted component antioxidant activity against DPPH indicated an IC50 value of around 30 µg/mL. [ABSTRACT FROM AUTHOR]

Passiflora spp. or passion fruit is a tropical plant that is often used as a food source. The large morphological variations of Passiflora cause difficulties in identifying the species. The objectives of the study are to identify the specific morphological and anatomical characters of Passiflora spp. in Yogyakarta and to determine their phenetic relationship for identification. A total of 15 samples of Passiflora were taken by purposive sampling technique from Bantul, Sleman, Kulon Progo, and Yogyakarta City, and then carried through the morphological and anatomical characterization. The morphological characters observed stems, leaves, and flowers, while the anatomical characters observed leaves. The results show that the observed samples are identified as four species, P. foetida, P. vitifolia, P. edulis, and P. quadrangularis. The P. edulis species consists of two forms, P. edulis f. flavicarpa and P. edulis f. edulis. The variation of morphological character lie in young stem shape, leaf shape, the texture of stem and leaf surface, bract shape and color, sepal and petal color, and the presence of a purple corona ring. While the variation of anatomical characters lie in the pattern of the vascular bundles, the shape of the upper and lower sides of the leaf veins, the shape and size of the palisade cells, as well as the type and density of stomata. Based on the phenetic analysis on the 0.8 phenon line, four main clusters were formed, P. foetida, P. vitifolia, P. edulis, and P. quadrangularis. [ABSTRACT FROM AUTHOR]

Baccaurea is a group of fruit-bearing potential wild tropical plants. West Sumatra is one of the Indonesian provinces with a sizable forest area. However, the high deforestation rate threatens the germplasm, especially Baccaurea wild plants, before well exploring their potential. The study aimed to analyze the sequence characters and phylogenetics of Baccaurea species found in West Sumatra using ITS molecular markers. DNA extraction relied on the Kit protocol using ITS molecular markers. The study employed the MEGA X application for sequence analysis and kinship relationships. Results of the analysis based on sequence characters of Baccaurea’s six species showed lengths ranging from 696 to 749 bp, the percentage composition of G + C bases (63.8%) and A + T bases (36.2%), the range of genetic distance (1%–5%), the number of conservative characters (549 bp), the number of informative characters (69 bp), and the point mutation in the nucleotide sequence (369 and 489). Meanwhile, the phylogenetic analysis using the ML method grouped the six species of Baccaurea to form a monophyletic clade with a bootstrap value of 100%-99%-100%. The results revealed for the first time the inclusion of ITS sequences of six Baccaurea species indigenous to West Sumatra in the NCBI database, which can benefit future investigations in identifying Baccaurea species and as a valuable reference for plant breeding in Baccaurea wild fruit plants’ development and conservation. [ABSTRACT FROM AUTHOR]

Garcinia pedunculata, a tropical plant found abundantly in the north-east region of India, has been used by many traditional healers for various gastrointestinal ailments. Studies are being carried out for the proper pharmacological identification of the compounds as well as the mode of action for the treatment of various diseases. In this study, phytochemistry of the fruit was evaluated, followed by a quantitative analysis of the total phenolic and flavonoid content of the methanolic crude extract as well as different fractions (n-hexane, chloroform, ethyl acetate, and n-butanol). The fraction with the most potent flavonoid and phenolic content was evaluated for its anti-inflammatory activity using both in vitro and in vivo assays. The chloroform fraction of G. pedunculata fruit extract was found to have a substantial amount of phenols and flavonoids. This fraction inhibited the denaturation of BSA and significantly stabilized human RBC membrane compared to the standard drug Diclofenac sodium. The fraction also significantly reduced the formaldehyde-induced paw edema in mice and normalized the blood parameters. This study provides evidence that G. pedunculata fruit extract plays a critical role in anti-inflammatory activity, indicating that it can be a potential candidate for further investigation in the treatment of inflammation-related diseases. [ABSTRACT FROM AUTHOR]

Karst areas in Indonesia are arid landscapes with water-use limitations because of dissolved carbonates. Long-term water scarcity stunts plant growth and often kills them. For tropical karst forestry-greening, the three best legume and three best non-legume species from a previous trial comprising 20 species were compared. Since October 2011, seedlings of the top three non-legume, species Aleurites mollucana, Sterculia foetida, and Alstonia scholaris, and three legume species, Acacia auriculiformis, Cassea seamea, and Acacia mangium, have been grown for four months. In January 2012, field trials were established at two dry karst locations, i.e., Pracimantoro, Central Java, and Bunder, Gunung Kidul Yogyakarta. A randomized block design was used to raise 1.764 seedlings at the two sites with 7x7 plots, 3x3 spacing between trees, and three blocks. After 10 months, legumes and non-legumes differed greatly in all growth parameters. These disparities lasted up to 30 months, when trees should have adapted to their new surroundings. After seven years of planting, legume trees raised the soil's organic matter concentration from low to medium, making it more fertile, similar to soil from intensive agricultural regions. Thus, early or mixed legume plantings on tropical karst sites may aid in better re-greening than the establishment of non-legumes. [ABSTRACT FROM AUTHOR]

Unlike majority of generalist predators of soft-body phytophagous insects, the giant ladybeetle predator, Anisolemnia dilatata (Fabricius), is a specialist predator of woolly aphids of bamboo plants in parts of tropical Asia. This predator has a long development time and reproductive duration. This study investigated through a field-cum-laboratory approach how a predator optimizes its reproductive and generational timing in bamboo habitats with patchy resources of woolly aphids. Results revealed that the giant ladybeetle females produced 69.20% of total eggs in the high prey density phase (mean ± SEM: 52.52 ± 9.65 aphids/leaf), comprising an average of 11 weeks out of the prey population cycle of 38 weeks. However, gravid females initiated egg-laying at a minimum average prey density of 16.35 aphids/leaf. Females chose narrow and thin parts of bamboo plants for depositing egg batches at a minimum distance of 21.05 cm and a maximum of 46.95 cm from the nearest aphid colony. Such behaviour is unique in aphidophagous predators directed at avoiding egg predation from actively growing conspecific or heterospecific larvae that continue to feed aphids after cessation of egg-laying in the declining phase of the population when prey resources become scarce. [ABSTRACT FROM AUTHOR]

Hybridization has significant evolutionary consequences across the Tree of Life. The process of hybridization has played a major role in plant evolution and has contributed to species richness and trait variation. Since morphological traits are partially a product of their environment, there may be a link between hybridization and ecology. Plant hybrid species richness is noted to be higher in harsh environments, and we explore this hypothesis with a keystone tropical plant lineage, palms (Arecaceae). Leveraging a recent literature review of naturally occurring palm hybrids, we developed a method to calculate hybrid frequency, and then tested if there is phylogenetic signal of hybrids using a phylogeny of all palms. Further, we used phylogenetic comparative methods to examine the interaction between hybrid frequency and presence in dry environments, on islands, and the species richness of genera. Phylogenetic generalized least squares models had stronger support than models of random association, indicating phylogenetic signal for the presence of hybrids in dry and island environments. However, all p‐values were >.05 and therefore the correlation was poor between hybridization and the trait frequencies examined. Presence in particular environments are not strongly correlated to hybrid frequency, but phylogenetic signal suggests a role in its distribution in different habitats. Hybridization in palms is not evenly distributed across subfamilies, tribes, subtribes yet plays an important role in palm diversity, nonetheless. Increasing our understanding hybridization in this economically and culturally important plant family is essential, particularly since rates are projected to increase with climate change, reconfiguring the dynamics and distribution of biodiversity. [ABSTRACT FROM AUTHOR]

• Synergistic effect on tyrosinase inhibition activity of Cassia fistula flower extract and Gynura procumbens leaf extract. • Antagonism of this combinarion occureed at lower concentration (Fa < 0.5). • The quantitative result of the synergistic effect were obtained using CompuSyn software. The antioxidants and tyrosinase inhibitors found in plants are promising agents in skincare products. Cassia fistula and Gynura procumbens are tropical plants found in many Southeast Asian countries. This study evaluated the antioxidant and tyrosinase inhibitory activities of ethanol extracts prepared from Cassia fistula flowers and Gynura procumbens leaves. The antioxidant activity of Cassia fistula flower and Gynura procumbens leaf extracts were investigated via the stable free radical 2,2-diphenyl-1-picrylhydrazyl method. The tyrosinase inhibitor effects of extracts and its combination against tyrosinase were examined with L-DOPA as substrate. The synergistic effect of Cassia fistula flower and Gynura procumbens leaf extracts combination was demonstrated by using the combination index method based on the median-effect principle that allows quantitative determination of its combination, where CI < 1, =1, and >1 indicates synergism, additive effect and antagonism, respectively. The CompuSyn software was used for determining synergism and antagonism at all concentrations or effects levels simulated automatically. The antioxidant activity of Cassia fistula flower extract was 2.7-fold higher than Gynura procumbens leaf extract, but the tyrosinase inhibitor activity was lower. The combination of Cassia fistula extract and Gynura procumbens extract in ratio 7:1.2 demonstrated synergistic effects when the inhibition was greater than 50 % with the CI ranged 0.90 to 0.49 for the fractional inhibition of Fa = 0.50–0.95. In conclusion, this combination demonstrated a synergistic effect and may be used further in cosmetic formulation. [ABSTRACT FROM AUTHOR]

The flowers of Peperomia (Piperaceae) are simple, minute, and unique structures within the angiosperms consisting of a rounded bract, two stamens and an ovary, but generally lack taxonomic value at species level. Because of this, morphological characters of vegetative parts have been mainly used for species level taxonomy. There is a need to supplement these vegetative characters with anatomical characters. We selected 17 native Thai species representatives of South East Asian Peperomia to investigate the utility of vegetative anatomical characters for species delimitation, taxon identification, and classification. Stem, petiole, and leaf anatomical characters were studied using standard microscopic techniques. The anatomical characters demonstrated high diversity and supported species identification. Unweighted Pair Group Method with Arithmetic Mean (UPGMA) culstering, Principal Coordinates analysis (PCoA), and Principal Component Anaysis (PCA) were used to investigate patterns in the multivariate anatomical data and identify groupings of value to species classification. Four broad groupings were retrieved and some subgroupings identified. The most important characters that differentiated the species in the multivariate analysis included stem shape (roundness and ridges), petiole indumentum and trichome type, vascular bundle pattern and number, stem pith cavity, mucilage canals, and stem cortex sclerenchyma. These data were further used to prepare anatomical descriptions at generic and species levels and to provide a key to species. [ABSTRACT FROM AUTHOR]

The European Commission requested the EFSA Panel on Plant Health to conduct a pest categorisation of Ceroplastes rubens Maskell (Hemiptera: Coccidae), following the commodity risk assessments of Acer palmatum plants grafted on A. davidii and Pinus parviflora bonsai plants grafted on P. thunbergii from China, in which C. rubens was identified as a pest of possible concern to the European Union (EU). The pest, which is commonly known as the pink, red or ruby wax scale, originates in Africa and is highly polyphagous attacking plants from more than 193 genera in 84 families. It has been present in Germany since 2010 in a single tropical glasshouse. It is known to attack primarily tropical and subtropical plants, but also other host plants commonly found in the EU, such as Malus sylvestris, Prunus spp., Pyrus spp. and ornamentals. It is considered an important pest of Citrus spp. The pink wax scale reproduces mainly parthenogenetically, and it has one or two generations per year. Fecundity ranges from 5 to 1178 eggs. Crawlers settle usually on young twigs and later stages are sessile. All life stages of C. rubens egest honeydew on which sooty mould grows. Host availability and climate suitability suggest that parts of the EU would be suitable for establishment. Plants for planting and cut branches provide the main pathways for entry. Crawlers could spread over short distances naturally through wind, animals, humans or machinery. C. rubens could be dispersed more rapidly and over long distances via infested plants for planting for trade. The introduction of C. rubens into the EU could lead to outbreaks causing damage to orchards, amenity ornamental trees and shrubs. Phytosanitary measures are available to inhibit the entry and spread of this species. C. rubens satisfies the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union quarantine pest. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is a key element for energy transfer, and biosynthesis of nucleic acids and cell membranes. The objective of this study was to investigate and quantify P utilization by different grain—maize (Zea mays L.) and soybean (Glycine max L.)—and forage-cover crop brachiaria (Brachiaria ruziziensis) plant species in a low fertility highly weathered Oxisol. Two rates of P (25 and 50 mg kg−1) were applied by water-soluble P fertilizer (triple superphosphate) to each of 12 crop cycles, together with a control (no P added). Measurements included plant biomass production and P uptake for each cycle, and analysis of soil P fractions (including labile and non-labile) and enzymes activities (acid phosphatase and β-glucosidase) were done at the beginning of the experiment and after 3, 6, and 12 cycles. Total biomass production and P uptake/removal were significantly higher for brachiaria than maize and soybean, which was reflected in the P use efficiency (PUE), being higher for brachiaria (57%), compared with maize (26%) and soybean (21%). The higher PUE by brachiaria was partly attributed to higher levels of acid phosphatase and β-glucosidase activities which indicated enhanced biological activity and P cycling under brachiaria. Data from the control treatment clearly demonstrated that all three plant species mobilized stable/occluded fractions of P throughout the experiment, however, brachiaria could produce more using less P. The findings of this study indicated the inclusion of brachiaria in crop rotations as a forage or cover crop/green manure may enhance overall P use efficiency. [ABSTRACT FROM AUTHOR]

The increasing frequency and intensity of heat waves caused significant damages to urban woody species, and the different leaf structures between evergreen and deciduous species may be closely related to leaf heat tolerance. However, whether the different leaf structural traits of evergreen and deciduous plants contribute to their different responses under heat waves is still unclear.During the record‐breaking and long‐lasting 2022 summer heat waves in China, we investigated the relationships between leaf thermal indices and leaf structural traits of 36 urban woody species in four cities along the Yangtze River.We found that all the four thermal indices were significantly but weakly related with leaf damage status. The critical temperature that causes the initial 15% damage to photosystem II (Tcrit) may serve as a sensitive measure of heat tolerance. Evergreen species suffered less leaf damage during the heat waves and exhibited higher leaf heat tolerance, thicker leaves than deciduous species. Tcrit was significantly correlated with leaf mass per area, leaf thickness and thickness of spongy tissue.Synthesis. Urban woody species with higher Tcrit, leaf mass per area and leaf thickness tend to be more tolerant to heat stress. This study provides insights for predicting leaf heat tolerance of urban woody plants in subtropical China and their physiological and ecological responses to severe heat waves. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

n the Neotropics, the focus of apomictic studies predominantly centres on trees within the Brazilian savanna, characterized, mostly as sporophytic and facultative, associated with polyploidy and polyembryony. To enhance our understanding of the mechanisms governing apomixis and sexual reproduction in tropical herbaceous plants, we clarify the relationship between apomixis, chromosome counts, and polyembryony in the epiphytic orchid Zygopetalum mackayi , which forms a polyploid complex within rocky outcrops in both the Brazilian savanna and the Atlantic forest. To define embryo origins and describe megasporogenesis and megagametogenesis, we performed manual self-pollinations in first-day flowers of cultivated plants, considering all three cytotypes (2 x , 3 x , 4 x) of this species. Flowers and fruits at different stages were collected to describe the development and morphology of ovules and seeds considering sexual and apomictic processes. As self-pollination treatments resulted in high fruit abortion in diploids, we also examined pollen tube development in aborted flowers and fruits to search for putative anomalies. Megasporogenesis and megagametogenesis occur regularly in all cytotypes. Apomixis is facultative and sporophytic, and associated with polyploid cytotypes, while diploid individuals exclusively engage in sexual reproduction. Polyembryony is caused mainly by the production of adventitious embryos from nucellar cells of triploids and tetraploids, but also by the development of multiple archesporia in all cytotypes. Like other apomictic angiosperms within the Brazilian savanna, our findings demonstrate that apomixis in Z. mackayi relies on pollinators for seed production. We also consider the ecological implications of these apomictic patterns in Z. mackayi within the context of habitat loss and its dependence on pollinators. [ABSTRACT FROM AUTHOR]

Plant invasions threaten the biodiversity of islands, causing serious impacts on their ecosystems. To investigate the distribution patterns of invasive alien plants on subtropical islands, the environmental determinants of species richness, and the growth forms of invasive alien plants, this study analyzed the composition and origin of invasive alien plants on 77 islands in Fujian. The similarity in the distribution of invasive alien plants between islands was assessed using the UPGMA. Moreover, feature selection, best-subset regression, and variance decomposition were performed using 19 environmental variables characterizing climate, anthropogenic disturbance, and landscape/geography, as well as the species richness and growth forms of invasive alien plants. Through the analysis, the main environmental factors affecting the species richness and growth forms of invasive alien plants on the Fujian islands were identified. The results showed 142 species of invasive alien plants in 38 families and 102 genera on 77 islands in Fujian. Annual herbs constituted the most representative growth form of invasive alien plants and tropical America was the main origin of invasive alien plants. The distribution of invasive alien plants across the 77 islands in Fujian showed a high degree of similarity, suggesting a nested pattern in their distribution. The proportions of building and farmland area (BFA), island area (A), and maximum elevation (ME) were the main driving factors of species richness and growth forms for invasive alien plants. In particular, BFA played a key role in driving plant invasion. The results of this study can help establish an early warning mechanism for invasive alien plants and better implement island ecological management, which are important for the protection of subtropical island ecosystems. [ABSTRACT FROM AUTHOR]

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