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Approximately 20,000 species of flowering plant offer mainly pollen to their pollinators, generally bees. Stamen dimorphism, a floral trait commonly present in some pollen flowers, is thought to be associated with exclusive pollen provision for highly effective bee pollinators. Notwithstanding, little is known about how stamen dimorphism is related to other floral morphological traits and, consequently, plant-pollinator interactions at the community scale. Here we investigated the relationship between stamen dimorphism and other floral morphological traits, as well as the interactions with pollinators in plants of Melastomataceae. We characterized each plant species as stamen dimorphic or stamen isomorphic according to differences in size and shape between stamen sets. Data on interactions between the plants and their bee pollinators were analysed as quantitative bipartite networks. We found that petal and style size and shape were correlated to stamen dimorphism. Stamen dimorphic species present larger flowers and less variable style shapes than stamen isomorphic species. Furthermore, stamen dimorphism is associated with higher richness of visiting bees, i.e. higher ecological generalization. During the evolutionary history of Melastomataceae, the dependence on pollinators for fruit set has possibly favoured the evolution of larger flowers with dimorphic stamens, which in turn are able to make use of a larger spectrum of pollen-collecting bees, leading to ecological generalization.

Phylogenetic relationship among seed plants recently obtained with molecular genetics fails to reveal the evolutionary steps of the formation of the basic morphotype of flowering plants. This task can be solved via morphological functional modeling of the first steps of the formation of flowering plants based on appropriate morphotypes in extant flora, irrespective of their genetic kinship. For instance, Gnetales adhere phylogenetically to conifers, but the genus Gnetum is appreciated for its numerous features convergent with angiosperms and can be used as a model of the morphological state of the angiosperm ancestor. A morphological analysis of the available data shows that the true angiosperm ancestor must have differed from Gnetum in some important respects, e.g., it must have had a more primitive xylem and bisexual fructifications. Aquatic intermediate stage modeled by water lilies is needed as a “bridge” that connects this ancestral condition with a full-fledged flowering plant. This intermediate stage differed from the extant water lilies in some crucial respects, e.g., it retained a cambium and possessed small flowers. The appearance of perianth with corolla is supposed to be possible at this aquatic stage only because it is water-wasteful. The scenario employs the concept of a megasporangia-bearing shoot, which is an alternative to the more common concept of a megasporangia-bearing leaf.

Drought is an environmental stress that limits agricultural and horticultural production worldwide. Paeonia lactiflora Pall. is a perennial flowering plant with strong environmental adaptability an...

An estimated 10% of flowering plant species conceal their pollen within tube-like anthers that dehisce through small apical pores (poricidal anthers). Bees extract pollen from poricidal anthers through a complex motor routine called floral buzzing, whereby the bee applies vibratory forces to the flower stamen by rapidly contracting its flight muscles. The resulting deformation depend on the stamen’s natural frequencies and vibration mode shapes, yet for most poricidal species these properties have not been sufficiently characterized. We performed experimental modal analysis on Solanum elaeagnifolium stamens to quantify their natural frequencies and vibration modes. Based on morphometric and dynamic measurements, we developed a finite element model of the stamen to identify how variable material properties, geometry and bee weight could affect its dynamics. In general, stamen natural frequencies fell outside the reported floral buzzing range, and variations in stamen geometry and material properties were unlikely to bring natural frequencies within this range. However, inclusion of bee mass reduced natural frequencies to within the floral buzzing frequency range and gave rise to an axial-bending vibration mode. We hypothesize that floral buzzing bees exploit the large vibration amplification factor of this mode to increase anther deformation, which may facilitate pollen ejection.

Flowering plants have evolved enormous diversity and complexity of inflorescence architecture. One great model for studying complex inflorescence development and evolution is the Asteraceae (the sunflower family), which is one of the largest flowering plant families and widely distributed across the

For more than 225 million y, all seed plants were woody trees, shrubs, or vines. Shortly after the origin of angiosperms ∼140 million y ago (MYA), the Nymphaeales (water lilies) became one of the first lineages to deviate from their ancestral, woody habit by losing the vascular cambium, the meristematic population of cells that produces secondary xylem (wood) and phloem. Many of the genes and gene families that regulate differentiation of secondary tissues also regulate the differentiation of primary xylem and phloem, which are produced by apical meristems and retained in nearly all seed plants. Here, we sequenced and assembled a draft genome of the water lily Nymphaea thermarum , an emerging system for the study of early flowering plant evolution, and compared it to genomes from other cambium-bearing and cambium-less lineages (e.g., monocots and Nelumbo ). This revealed lineage-specific patterns of gene loss and divergence. Nymphaea is characterized by a significant contraction of the HD-ZIP III transcription factors, specifically loss of REVOLUTA , which influences cambial activity in other angiosperms. We also found the Nymphaea and monocot copies of cambium-associated CLE signaling peptides display unique substitutions at otherwise highly conserved amino acids. Nelumbo displays no obvious divergence in cambium-associated genes. The divergent genomic signatures of convergent loss of vascular cambium reveals that even pleiotropic genes can exhibit unique divergence patterns in association with independent events of trait loss. Our results shed light on the evolution of herbaceousness—one of the key biological innovations associated with the earliest phases of angiosperm evolution.

Over the decades, extensive studies have been performed to elucidate the molecular mechanisms underlying the floral transition process in model plants, as well as in crop plants. It has been demonstrated that floral integrator genes, such as FLOWERING LOCUS T and SUPPRESSOR OF OVEREXPRESSION OF CO 1, are highly conserved in most of the flowering plants. This finding has accelerated the identification and functional analyses of these orthologues involved in floral transition in flowering plant species. Even though the upstream regulator networks of the floral integrator genes seem to be quite diverged among plant species, they share four conserved flowering pathways, including the photoperiod, autonomous, gibberellin, and vernalization pathways. The comprehensive knowledge of the molecular mechanisms underlying floral transitions in the model plant Arabidopsis thaliana has helped us explore and elucidate the molecular mechanisms controlling floral transitions in other crop plants. This review highlights the current understandings of the flowering pathways elucidated in Arabidopsis, and mainly focuses on understanding the vernalization pathway in Arabidopsis as well as in several horticultural crop plants, including those of the genus Brassica.

Chrysanthemum boreale (Asteraceae) is a wild flowering plant that has both ornamental and herbal uses. In the present study, colchicine was used as a chemical mutagen to induce polyploidy using in vitro shoots, which were cultured from C. boreale (2n = 2x = 18) nodal segments, and the efficacy of various colchicine concentrations and treatment durations were investigated. The results demonstrated that the induction of tetraploid plants by colchicine treatment were clearly successful. A total of 21 tetraploid and 110 chimera plants were identified using the chromosome counting method, and the colchicine concentrations of 200 ppm (48 h) and 300 ppm (12 and 24 h) were the most effective for inducing tetraploidy. Details about the successful induction, morphological characteristics, and cytology of the polyploids are described and compared with those of control plants. The tetraploid plants exhibited thicker and larger leaves, as well as larger and fewer stomata than the diploid plants. In this study, the polyploid plants of Chrysanthemum were induced successfully using colchicine treatment. This procedure contributed to the improvement of high-value species in the Chrysanthemum breeding program.

Rhynchotechum parviflorum Blume earlier known to occur in Nicobar Islands of India is now recorded for the first time from Upper Siang of Arunachal Pradesh, Mainland India. A short description along with colour images are provided for easy identification.

Significance Since Darwin, insect pollination was thought to be a key contributor to the Cretaceous radiation of angiosperms. Both insects and angiosperms were common during the mid-Cretaceous, but direct evidence for a Cretaceous insect-angiosperm pollination mode was until now absent. Here, we report a specialized beetle-angiosperm pollination mode preserved in Burmese amber where a tumbling flower beetle is carrying tricolpate pollen grains that belongs to the eudicots that comprise the majority of extant angiosperm species. Our study provides direct evidence of insect pollination of Cretaceous flowers, which is further supported by the flower-visiting body shape, specialized pollen-feeding mouthparts, and zoophilous pollen grains. These findings demonstrate that insect pollination of flowering plants was well established 99 million years ago., Insect pollination of flowering plants (angiosperms) is responsible for the majority of the world’s flowering plant diversity and is key to the Cretaceous radiation of angiosperms. Although both insects and angiosperms were common by the mid-Cretaceous, direct fossil evidence of insect pollination is lacking. Direct evidence of Cretaceous insect pollination is associated with insect-gymnosperm pollination. Here, we report a specialized beetle-angiosperm pollination mode from mid-Cretaceous Burmese amber (99 mega-annum [Ma]) in which a tumbling flower beetle (Mordellidae), Angimordella burmitina gen. et sp. nov., has many tricolpate pollen grains attached. A. burmitina exhibits several specialized body structures for flower-visiting behavior including its body shape and pollen-feeding mouthparts revealed by X-ray microcomputed tomography (micro-CT). The tricolpate pollen in the amber belongs to the eudicots that comprise the majority of extant angiosperm species. These pollen grains exhibit zoophilous pollination attributes including their ornamentation, size, and clumping characteristics. Tricolpate pollen grains attached to the beetle’s hairs are revealed by confocal laser scanning microscopy, which is a powerful tool for investigating pollen in amber. Our findings provide direct evidence of insect pollination of Cretaceous angiosperms, extending the range insect-angiosperm pollination association by at least 50 million years. Our results support the hypothesis that specialized insect pollination modes were present in eudicots 99 million years ago.

Specialized photosynthetic organs have appeared several times independently during the evolution of land plants. Phyllids, the leaf-like organs of bryophytes such as mosses or leafy liverworts, display a simple morphology, with a small number of cells and cell types and lack typical vascular tissue which contrasts greatly with flowering plants. Despite this, the leaf structures of these two plant types share many morphological characteristics. In this review, we summarize the current understanding of leaf morphogenesis in the model moss Physcomitrium patens, focusing on the underlying cellular patterns and molecular regulatory mechanisms. We discuss this knowledge in an evolutionary context and identify parallels between moss and flowering plant leaf development. Finally, we propose potential research directions that may help to answer fundamental questions in plant development using moss leaves as a model system.

To meet the pollination need of economic crops, Osmia excavata has been successfully used to improve the pollination efficiency of Rosaceae and Brassicaceae plants. As a widely used pollinator of economic crops, a systematic study of flower-visiting species and diversities of O. excavata stocked in China was not found. To investigate the foraging pollen species and diversities of O. excavata, beebread from 20 experimental plots in China was collected by the trap-nesting method and analyzed by DNA metabarcoding technology. A total of 26 pollen plants in 14 genera and nine families were identified. A further analysis showed that the richness and abundance of the wild flowering plants in orchards and farmlands were lower than those in the nearby semi-natural habitats. The favorite pollen comes from economic crops apple and rape and wild flowering plants Juncus interior, Rosa gymnocarpa, and Rosa laevigata. Through a diversity index analysis, it was found that the Anhui region has the highest pollen plant diversity, while the Liaoning region has the lowest. Our results can provide a basis for flower-visiting species and diversities of O. excavata.

5 Pág. Centro de Biotecnología y Genómica de Plantas

Background Most orchid species have been shown to be severely pollination limited, and the factors affecting reproductive success have been widely studied. However, the factors determining the reproductive success vary from species to species. Habenaria species typically produce nectar but exhibit variable fruit set and reproductive success among species. Here, we investigated the influence of the flowering plant density, inflorescence size, breeding system, and pollinator behaviour on the reproductive success of two rewarding Habenaria species. Results Our observations indicated that Habenaria limprichtii and H. petelotii co-occur in roadside verge habitats and present overlapping flowering periods. Both species were pollination limited, although H. limprichtii produced more fruits than H. petelotii under natural conditions during the 3-year investigation. H. petelotii individuals formed distinct patches along roadsides, while nearly all H. limprichtii individuals clustered together. The bigger floral display and higher nectar sugar concentration in H. limprichtii resulted in increased attraction and visits from pollinators. Three species of effective moths pollinated for H. limprichtii, while Thinopteryx delectans (Geometridae) was the exclusive pollinator of H. petelotii. The percentage of viable seeds was significantly lower for hand geitonogamy than for hand cross-pollination in both species. However, H. limprichtii may often be geitonogamously pollinated based on the behaviours of the pollinators and viable embryo assessment. Conclusions In anthropogenic interference habitats, the behaviours and abundance of pollinators influence the fruit set of the two studied species. The different pollinator assemblages in H. limprichtii can alleviate pollinator specificity and ensure reproductive success, whereas the more viable embryos of natural fruit seeds in H. petelotii suggested reducing geitonogamy by pollinators in the field. Our results indicate that a quantity-quality trade-off must occur between species with different breeding strategies so that they can fully exploit the existing given resources.

Stomata evolved as plants transitioned from water to land, enabling carbon dioxide uptake and water loss to be controlled. In flowering plants, the most recently divergent land plant lineage, stomatal pores actively close in response to drought. In this response, the phytohormone abscisic acid (ABA) triggers signalling cascades that lead to ion and water loss in the guard cells of the stomatal complex, causing a reduction in turgor and pore closure. Whether this stimulus-response coupling pathway acts in other major land plant lineages is unclear, with some investigations reporting that stomatal closure involves ABA but others concluding that closure is passive. Here we show that in the model fernCeratopteris richardiiactive stomatal closure is conditional on sensitisation by pre-exposure to either low humidity or exogenous ABA and is promoted by ABA. RNA-seq analysis andde novotranscriptome assembly reconstructed the protein coding complement of theC. richardiigenome with coverage comparable to other plant models, enabling transcriptional signatures of stomatal sensitisation and closure to be identified. In both cases, changes in abundance of homologs of ABA, Ca2+and ROS-related signalling components were observed, suggesting that the closure response pathway is conserved in ferns and flowering plants. These signatures further suggested that sensitisation is achieved by lowering the threshold required for a subsequent closure-inducing signal to trigger a response. We conclude that the canonical signalling network for active stomatal closure functioned in at least a rudimentary form in the stomata of the last common ancestor of ferns and flowering plants.Significance StatementStomata are valve-like pores that control the uptake of CO2and the loss of water vapour in almost all land plants. In flowering plants, stomatal opening and closure is actively regulated by a stimulus-response coupling network. Whether active stomatal responses are present in other land plant lineages such as ferns has been hotly debated. Here we show that stomatal responses in the fernCeratopteris richardiiare active but depend on their past growth environment, and demonstrate that fern stomatal closure and sensitisation are associated with the altered expression of genes whose homologs function in the canonical stomatal regulatory network of flowering plants. Genetic pathways for active stomatal regulation therefore most likely evolved before the divergence of ferns and flowering plants.

Summary Stomata evolved as plants transitioned from water to land, enabling carbon dioxide uptake and water loss to be controlled. In flowering plants, the most recently divergent land plant lineage, stomatal pores actively close in response to drought. In this response, the phytohormone abscisic acid (ABA) triggers signaling cascades that lead to ion and water loss in the guard cells of the stomatal complex, causing a reduction in turgor and pore closure. Whether this stimulus-response coupling pathway acts in other major land plant lineages is unclear, with some investigations reporting that stomatal closure involves ABA but others concluding that closure is passive. Here, we show that in the model fern Ceratopteris richardii active stomatal closure is conditional on sensitization by pre-exposure to either low humidity or exogenous ABA and is promoted by ABA. RNA-seq analysis and de novo transcriptome assembly reconstructed the protein-coding complement of the C. richardii genome, with coverage comparable to other plant models, enabling transcriptional signatures of stomatal sensitization and closure to be inferred. In both cases, changes in abundance of homologs of ABA, Ca2+, and ROS-related signaling components were observed, suggesting that the closure-response pathway is conserved in ferns and flowering plants. These signatures further suggested that sensitization is achieved by lowering the threshold required for a subsequent closure-inducing signal to trigger a response. We conclude that the canonical signaling network for active stomatal closure functioned in at least a rudimentary form in the stomata of the last common ancestor of ferns and flowering plants.

Description, A global dataset shows that animal pollinators are crucial for reproduction in half of wild flowering plants., Despite evidence of pollinator declines from many regions across the globe, the threat this poses to plant populations is not clear because plants can often produce seeds without animal pollinators. Here, we quantify pollinator contribution to seed production by comparing fertility in the presence versus the absence of pollinators for a global dataset of 1174 plant species. We estimate that, without pollinators, a third of flowering plant species would produce no seeds and half would suffer an 80% or more reduction in fertility. Pollinator contribution to plant reproduction is higher in plants with tree growth form, multiple reproductive episodes, more specialized pollination systems, and tropical distributions, making these groups especially vulnerable to reduced service from pollinators. These results suggest that, without mitigating efforts, pollinator declines have the potential to reduce reproduction for most plant species, increasing the risk of population declines.

Brown continued to work on his taxonomic studies (which helped influence the growth of the natural system of classification in England). He picked up the threads of research that he had begun earlier, studying the minute structure of the vegetative and reproductive organs of plants. It was while he conducted this work that he made an important discovery concerning the behavior or action of minute particles. This was the discovery of the phenomenon of “Brownian motion,” an achievement that epitomized his journey from a descriptive naturalist to an investigative scientist. Brown studied the pollen grains of the flowering plant, Clarkia pulchella (commonly called elkhorns or ragged robin, pink fairy, clarkia or deerhorn)—in fluids such as water. He demonstrated that any kind of matter, whether organic or inorganic and reduced to smaller particles, would exhibit random movement when suspended in a medium like water. Brown did not understand the actual cause of the random motion of the particles but his observation proved to be relevant to biologists and physical scientists as well. Brown accomplished further breakthroughs during this period (from the late 1820s to the 1850s). His recognition of the “naked” (uncovered) condition of the ovules in the cycads and conifers eventually led to the taxonomic division of seed plants into two distinct groups, the gymnosperms, conifers and cycads, and flowering plants, the angiosperms. He also conducted significant work in cytology, developing a deeper understanding of the composition of the cell. He identified the phenomenon of protoplasmic streaming. Perhaps most important was Brown’s observation of the nucleus in certain plant cells, an observation made by several other pioneers in cytology although Brown did not grasp the full significance of his discovery at the time. Brown deserves credit for ascertaining that matter, inorganic or organic, when broken down into finer particles but still visible microscopically, would exhibit discernible random motion when suspended in water or other fluids. When young Charles Darwin went to Brown to be tutored in microscopy, Brown showed him the protoplasmic streaming he had observed in plant cells. On November 1, 1831, he presented “The discovery of the nucleus of the vegetable cell” before the Linnean Society, reporting his important microscopic observations. Brown’s focus during the last few decades of his life was in paleobotany, earlier marked by a fossil-hunting trip he took to the Burgundy region of France in 1836. Brown continued to publish work describing in minute detail the fine structure of plant fossils, illustrated by his 1847 paper on the strobilus of the cone of an extinct fossil plant, a treelike organism related to the Lycopsids or club mosses belonging to the genus Lepidodendron.

The seeds of flowering plants are sexually produced propagules that ensure dispersal and resilience of the next generation. Seeds harbor embryos, three dimensional structures that are often miniatures of the adult plant in terms of general structure and primordial organs. In addition, embryos contain the meristems that give rise to post-embryonically generated structures. However common, flowering plant embryos are an evolutionary derived state. Flowering plants are part of a much larger group of embryo-bearing plants, aptly termed Embryophyta. A key question is what evolutionary trajectory led to the emergence of flowering plant embryos. In this opinion, we deconstruct the flowering plant embryo and describe the current state of knowledge of embryos in other plant lineages. While we are far yet from understanding the ancestral state of plant embryogenesis, we argue what current knowledge may suggest and how the knowledge gaps may be closed.

Successful fertilization in angiosperms depends on the proper trajectory of pollen tubes through the pistil tissues to reach the ovules. Pollen tubes first grow within the cell wall of the papilla cells, applying pressure to the cell. Mechanical forces are known to play a major role in plant cell shape by controlling the orientation of cortical microtubules (CMTs), which in turn mediate deposition of cellulose microfibrils (CMFs). Here, by combining imaging, genetic and chemical approaches, we show that isotropic reorientation of CMTs and CMFs in aged Col-0 andFlowering plants produce small particles known as pollen that – with the help of the wind, bees and other animals – carry male sex cells (sperm) to female sex cells (eggs) contained within flowers. When a grain of pollen lands on the female organ of a flower, called the pistil, it gives rise to a tube that grows through the pistil towards the egg cells at the base. The surface of the pistil is covered in a layer of long cells named papillae. Like most plant cells, the papillae are surrounded by a rigid structure known as the cell wall, which is mainly composed of strands known as microfibrils. The pollen tube exerts pressure on a papilla to allow it to grow through the cell wall towards the base of the pistil. Previous studies have shown that the pistil produces signals that guide pollen tubes to the eggs. However, it remains unclear how pollen tubes orient themselves on the surface of papillae to grow in the right direction through the pistil. Riglet et al. combined microscopy, genetic and chemical approaches to study how pollen tubes grow through the surface of the pistils of a small weed known as

Roots typically grow downward into the soil where they anchor the plant and take up water and nutrients necessary for plant growth and development. While the primary roots usually grow vertically downward, laterals often follow a gravity set point angle that allows them to explore the surrounding environment. These responses can be modified by developmental and environmental cues. This review discusses the molecular mechanisms that govern root gravitropism in flowering plant roots. In this system, the primary site of gravity sensing within the root cap is physically separated from the site of curvature response at the elongation zone. Gravity sensing involves the sedimentation of starch-filled plastids (statoliths) within the columella cells of the root cap (the statocytes), which triggers a relocalization of plasma membrane-associated PIN auxin efflux facilitators to the lower side of the cell. This process is associated with the recruitment of RLD regulators of vesicular trafficking to the lower membrane by LAZY proteins. PIN relocalization leads to the formation of a lateral gradient of auxin across the root cap. Upon transmission to the elongation zone, this auxin gradient triggers a downward curvature. We review the molecular mechanisms that control this process in primary roots and discuss recent insights into the regulation of oblique growth in lateral roots and its impact on root-system architecture, soil exploration and plant adaptation to stressful environments.

Keanekaragaman tumbuhan tidak hanya terlihat secara morfologi, tetapi dapat dibedakan pula secara anatomi. Ciri anatomi dapat digunakan sebagai pendukung dan penguat pengklasifikasian jenis tumbuhan. Penelitian ini bertujuan untuk mengetahui ciri anatomi daun yang dapat digunakan sebagai penciri taksonomi dalam suatu tingkatan taksa melalui perwakilan jenis. Jenis yang digunakan berjumlah 15, yang merupakan perwakilan dari 12 suku tumbuhan berbunga Indonesia. Metode parafin digunakan untuk mendapatkan penampang transversal dan metode perendaman dengan asam nitrit (HNO3) digunakan untuk mendapatkan penampang epidermis daun. Sebagian ciri anatomi pada penelitian dapat digunakan sebagai penciri suku hingga jenis. Hasil penelitian menunjukkan bahwa 15 jenis yang diamati memiliki kesamaan ciri anatomi dengan data penelitian terdahulu yang telah dilakukan baik pada tingkat suku, marga maupun jenis. Kesamaan ciri anatomi tersebut mencakup satu hingga beberapa ciri seperti tipe stomata, dinding antiklinal sel epidermis, jaringan mesofil, dan berkas pengangkut (tangkai daun dan tulang tengah daun). Kesamaan ciri yang didapatkan pada masing-masing jenis menunjukkan bahwa ciri pada struktur anatomi daun dapat menjadi bukti pembatasan takson pada tumbuhan berbunga.

Background With currently 1980 described species, the mega-diverse Begonia is now perhaps the 5th largest flowering plant genus, expanding rapidly from ca. 900 species in 1997 to its current size in merely two decades. In continuation of our studies of Asian Begonia, we report six additional new species from Guangxi, the region/province harboring the second richest Begonia flora of China. Results Based on morphological and molecular data, the new species B. aurora belongs to Begonia sect. Platycentrum, while the other five new species (viz. B. larvata, B. longiornithophylla, B. lui, B. scabrifolia, and B. zhuoyuniae) are members of Sect. Coelocentrum. Somatic chromosome numbers of B. longiornithophylla and B. zhuoyuniae at metaphase were counted as 2n = 30, consistent with previously reports for Sect. Coelocentrum. Conclusions With the addition of the six new species, the total number of Begonia species in Guangxi increases from 86 to 92. Detailed description, line drawings, and color plates are provided to aid in identification.

The family Apodanthaceae comprises two genera (Apodanthes and Pilostyles) and 11 endoparasitic species, all of them lacking root and shoot apical meristems, stems, and leaves. Their vegetative phase is reduced to a mycelium-like endophyte formed by strands of parenchyma cells that are in close contact to the host vasculature. These plants become apparent only when their tiny gregarious flowers emerge breaking through the host cortex. The lack of vegetative meristems in these plants sharply contrasts to the typical formation of floral meristems. Our target species, Pilostyles boyacensis, provides a suitable system to investigate the evolution of meristem-related genes in an endoparasitic flowering plant without a typical vegetative shoot apical meristem. We have generated transcriptomes from two different developmental stages of the parasite (emerged floral buds and fruits), as well as a mixed sample that comprises the endophyte and growing floral buds of the parasite and its host, Dalea cuatrecasasii (Fabaceae). We specifically assessed copy number and domain conservation for the WUSCHEL HOMEOBOX, LRR-RLK-IX-a, and CLE families related to the maintenance of the shoot apical meristem (SAM) as well as the ARF and LFY families responsible for floral meristem identity. Five out of the 11 canonical gene families responsible for SAM maintenance and floral fate determinacy targeted in this study were found in Pilostyles. P. boyacensis shows at least one transcript with all functional domains conserved for BAM1, WUS, WOX9, ARF7, and LFY. Other genes implicated in the canonical regulatory network could not be found, including ARF5, ARF19, BAM2, BAM3, CLV1, and CLV3. In conclusion, the endoparasitic lifestyle of Apodanthaceae appears to correlate with a substantial reduction in the transcriptomic machinery linked to SAMs, whereas the genes involved in flower fate have remained intact.

In plants, gibberellins (GAs) play important roles in regulating growth and development. Early studies revealed the large chemodiversity of gibberellins in plants, but only GA1, GA3, GA4, and GA7 show biological activity that controls plant development. However, the elucidation of the GA metabolic network at the molecular level has lagged far behind the chemical discovery of GAs. Recent advances in downstream GA biosynthesis (after GA12 formation) suggest that species-specific gibberellin modifications were acquired during flowering plant evolution. Here, we summarize the current knowledge of GA metabolism in flowering plants and the physiological functions of GA deactivation, with a focus on GA 13 hydroxylation. The potential applications of GA synthetic biology for plant development are also discussed.

Approximately 6% of flowering plant species possess flowers with anthers that open through small pores or slits. Extracting pollen from this type of specialised flower is achieved most efficiently by vibrating the anthers, a behaviour that has evolved repeatedly among bees. Here I provide a brief overview of the study of vibrations produced by bees and their effects on pollen release. I discuss how bee morphology and behaviour affect the mechanical properties of vibrations, and how floral traits may influence the transmission of those vibrations from the bee to the anther, thus mediating pollen release, and ultimately bee and plant fitness. I suggest that understanding the evolution of buzz pollination requires a study of the biomechanics of bee vibrations and their transmission on flowers.

Bamboo is a perennial flowering plant with a distinctive life cycle: many bamboo species remain in the vegetative phase for decades, followed by mass synchronous flowering and subsequent death. The phenomenon of bamboo flowering is not fully understood, but its periodicity is a major research focus. Here, we collected information on bamboo flowering events by investigating historical documents and field studies at the Bamboo Research Institute of Nanjing Forestry University. We compiled information on more than 630 flowering events, 124 of which accurately recorded the flowering cycle time. We summarized the specific flowering cycles of 85 bamboo species, as well as four kinds of bamboo flowering habits in detail. We present a theory of the bamboo flowering cycle and discuss the reasons for the observed variations in bamboo flowering. This review also introduces two mechanisms by which bamboo forests are rejuvenated after flowering and explains the flowering phenomena of bamboo forests using the bamboo flowering cycle theory. Finally, we present suggestions for forest management strategies. Bamboo flowering is a normal physiological phenomenon, even though it has unique elements compared with flowering in other plants. The results presented here provide valuable reference material for understanding bamboo flowering and its periodicity.

Background: Nymphaea capensis is an aquatic flowering plant which is included in the family of Nymphaeaceae. Literature review on the plants of Nymphaeaceae family exhibited significant medicinal activities. Therefore, the objective of the present study is to evaluate possible anti-oxidant activity of crude methanol extract of N. capensis leaf.Method: In antioxidant study, methanolic plant extract was evaluated for 1,1-diphenyl,2-picrylhydrazyl (DPPH) and reducing power capacity. Moreover, total phenolic and total flavonoid content of plant extracts were determined and expressed in mg of gallic acid equivalent per gram of dry sample (mg GAE/g dry weight).Result: In the DPPH free radical scavenging assay, methanol extract showed concentration dependent inhibition of the free radicals. IC50 of Ascorbic acid was 14.84 µg/ml whereas N. capensis was 130.94 µg/ml. In case of reducing capacity, at conc. 62.5, 125, 250, 500, 1000 ug/ml, the absorbances of Ascorbic acid were 0.65, 1.12, 1.45, 1.78 and 1.89 respectively. In case of N. capensis, the absorbances were 0.46, 0.75, 1.04, 1.27 and 1.50 respectively. The extract displayed a concentration dependent increase in reducing power. In the case of total phenolic content, the methanol extract of N. capensis contained a considerable amount of phenolic contents which was 215±7 of GAE mg/g. In the case of total flavonoid content, methanol extract of N. capensis contained significant amount of flavonoid contents which was 184.75±6.78 of GAE mg/g.Conclusion: These results suggested that the methanol extract of N. capensis possess considerable anti-oxidant activity.

Background Insect-vectored Leishmania are responsible for loss of more disability-adjusted life years than any parasite besides malaria. Elucidation of the environmental factors that affect parasite transmission by vectors is essential to develop sustainable methods of parasite control that do not have off-target effects on beneficial insects or environmental health. Many phytochemicals that inhibit growth of sand fly-vectored Leishmania—which have been exhaustively studied in the search for phytochemical-based drugs—are abundant in nectars, which provide sugar-based meals to infected sand flies. Principle findings In a quantitative meta-analysis, we compare inhibitory phytochemical concentrations for Leishmania to concentrations present in floral nectar and pollen. We show that nectar concentrations of several flowering plant species exceed those that inhibit growth of Leishmania cell cultures, suggesting an unexplored, landscape ecology-based approach to reduce Leishmania transmission. Significance If nectar compounds are as effective against parasites in the sand fly gut as predicted from experiments in vitro, strategic planting of antiparasitic phytochemical-rich floral resources or phytochemically enriched baits could reduce Leishmania loads in vectors. Such interventions could provide an environmentally friendly complement to existing means of disease control.

Salamah A, Luthfikasari R, Dwiranti A. 2019. Pollen morphology of eight tribes of Asteraceae from Universitas Indonesia Campus, Depok, Indonesia. Biodiversitas 20: 152-159. Asteraceae is one of the largest flowering plant families in the world consisting of a high diversity of species that possess many macro-morphological characters. Ecological pressures have resulted in this highly varied morphology. Our research aims to describe the pollen morphology of the Asteraceae for species occurring in Depok Campus of Universitas Indonesia. Pollens of 14 species from eight tribes were extracted using acetolysis method and observed under a light microscope. The result showed that pollen unity, shape and pollen surface appeared to be differentiating characters of the Asteraceae from other families, while polarity and symmetry characters can be distinguishing characters at higher levels of the family such as subdivisions. Aperture characters were useful to differentiate between tribes. The shape of pores and size of pollen were not useful in differentiating between tribes, but may differentiate between lower taxa. The results of this study could be used as supporting data for regrouping taxa within the Asteraceae using morphological features.

Paeonia daurica subsp. tomentosa (Lomakin) D.Y.Hong is an herbaceous perennial and flowering plant from the Paeoniaceae family. In this research, the roots, stems, leaves and fruits of P. daurica s...

Crepidiastrum sonchifolium, a flowering plant in the daisy family (Asteraceae), is native to East Asia. In Korea, this plant is a locally cultivated vegetable, and its market size is gradually growing. Since the plants with downy mildew infection were initially found at a private farm of Chuncheon city, the occurrences have continued in commercial farms of other regions, highlighting that this disease is spreading throughout Korea. The pathogen was attributed to a member of the genus Bremia that contains many specialized species, each of which displays a narrow host spectrum on Asteraceae. Based on morphological and molecular phylogenetic analyses, along with the high host specificity recently proven for Bremia species, the identity of the causal agent was confirmed as a so far undescribed species of Bremia. Here, we introduce Bremia itoana sp. nov., specific to C. sonchifolium.

Colobanthus quitensis is one of the two vascular plants inhabiting the Antarctic. In natural habitats, it grows in the form of a cushion or mats, commonly observed in high latitudes or alpine vegetation. Although this species has been investigated over many years to study its geographical distribution and physiological adaptations to climate change, very limited genetic information is available. The high-throughput sequencing with a de novo assembly analysis yielded 47,070 contigs with blast-hits. Through the functional classification and enrichment analysis, we identified that photosynthesis and phenylpropanoid pathway genes show differential expression depending on the habitat environment. We found that the known ‘plant core environmental stress response (PCESR)’ genes were abundantly expressed in Antarctic samples, and confirmed that their expression is mainly induced by low-temperature. In addition, we suggest that differential expression of thermomorphogenesis-related genes may contribute to phenotypic plasticity of the plant, for instance, displaying a cushion-like phenotype to adapt to harsh environments.

This study documents the occurrence of the fungal pathogen Inonotus rickii, which causes wood rot or heart rot; the leafy mistletoe Phoradendron tomentosum (subsp. macrophyllum); and the mycorrhizal fungus Pisolithus tinctorius in pecan orchards in southern New Mexico. The prevalence of orchards with I. rickii and P. tomentosum was low (3.3 to 3.6%). To our knowledge, I. rickii has not been previously described in association with pecan in New Mexico and the United States. Although the occurrence of P. tomentosum on pecan has been documented in the southeastern United States, it has not been reported in New Mexico. In contrast to the rarity of I. rickii and P. tomentosum, the mycorrhiza P. tinctorius was commonly found in pecan orchards surveyed. With the expansion of the pecan industry in New Mexico, it is important to continually monitor pecan orchards for emerging pests and pathogens that may impose an economic threat to production and to enhance the proliferation of biological entities with known beneficial properties for pecan health.

Pinesap Monotropa hypopitys is a myco-heterotrophic non-photosynthetic higher angiosperm perennial plant devoid of vegetative organs and with standard flower arrangement. The MADS-domain transcription factor family has multiple regulatory functions in plant life cycle and is implicated in flower evolution and diversity. This study is the first to describe the MADS-box genes in a myco-heterotrophic eudicot. By performing the M. hypopitys transcriptome-wide analysis, we identified 30 MADS-box genes belonging to the major clades in the MIKCc and MIKC* lineages. Among them, MhyMADS18 is suggested as an ancestral gene of the cluster comprising AP1/FUL, FLC, SEP, and AGL6 clades. The RNA-seq profiling of the MhyMADS expression in the flowering plant revealed mRNAs specific to bracts, flowers, and roots with adventitious buds. Our results represent systematic and expression analysis of the pinesap MADS-box genes that may be involved in seed dormancy regulation, flowering time control, and flower organ identity specification. The obtained data should further our understanding of the roles played by the MADS-box genes in developmental regulation of myco-heterotrophic plants.

Mosquito adults usually need to ingest sugar from nectar host plants to sustain their metabolic needs. Mosquitoes could be differentially attracted by various flowering plant species, and the volatiles were thought to be important factors attributed to the differential attractiveness. However, whether mosquitoes' preference for host plants correlates with their nutritional rewards from sugar sources remains unclear. In the present study, the preference of newly emerged Culex pipiens pallens to three kinds of flowering plants (Ligustrum quihoui, Abelia chinensis, and Nerium indicum) was determined in the olfactometer. Besides, when the newly emerged mosquitoes were provided with these flowering plants as sugar sources, the content of their metabolic reserves (glycogen, lipid, and protein) was determined. The results revealed that Cx. pipiens pallens could be differentially attracted by the odors emitted by the inflorescences of the tested flowering plants, and the nutritional rewards of mosquitoes were significantly affected by feeding on different inflorescences. The present study demonstrated that feeding on nectar host plants with differential attraction could affect the energy reserves of Cx. pipiens pallens.

Ecological engineering involves the use of plants to promote establishment, survival and efficiency of natural enemies in agricultural systems. Some plant species may be hosts or provide resources to some pest species. We assessed the risks and benefits of sesame (Sesamum indicum L.), as a nectar source for seven economically important Lepidopteran pest and four parasitoid species in a range of vegetable crop systems. Our results showed that the mean longevities of arthropod parasitoids Pteromalus puparum (L.), Encarsia sophia (Girault & Dodd) and male Microplitis tuberculifer (Wesmael) were significantly extended when fed on sesame flowers compared to the water control. Sesame flowers had no effect on adult longevities and fecundities of six out of the seven Lepidoptera pest species tested except Plutella xyllostella (L.) females laid more eggs when fed on sesame flowers. It is likely that the increased fecundity is due to accessibility to nectar at the bottom of corolla because of their smaller body sizes. Our findings provide a first step towards better understanding of the risks and benefits of using sesame to implement ecological engineering for the management of vegetable pests.

Carex kucyniakii is a poorly known, morphologically unusual Vietnamese sedge (sect. Hemiscaposae, Cyperaceae) that is part of an early diverging lineagewithin the genus. Fieldwork in Lao Cai Province resulted in the rediscovery of this species near its type locality and the detection of significant variation in the morphology of plants in nearby populations. Subsequent morphological andmolecular studies revealed that C. kucyniakii is a complex of three species. These taxa are endemic to the southern slopes of the Hoang Lien Mountains, in Lao Cai Province, and exhibit extraordinary morphological features including the widest leaves known for any Cyperaceae (pseudopetiolate and up to 12 cm), and for some taxa pink-red inflorescences. Of the three species recognized in the complex, C. kucyniakii is characterized by a combination of glabrous perigynia, scales, and peduncles, while in C. geographica sp. nov. and C. thinii sp. nov. these structures are pubescent/scabrous. In addition, the scales and perigynia in C. kucyniakii are green or brown while those in C. geographica and C. thinii are suffused with pink or red. Differences in pistillate and staminate scale morphology and anther length distinguish the latter two species. The Vietnamese Carex flora contains a high proportion of morphologically exceptional and poorly understood taxa, many from early diverging lineages in the genus. Our findings support the supposition that Indochina and East Asia could be the center of origin for the world's largest flowering plant genus and that the sedge flora of northern Vietnam contains a number of taxonomic novelties still remaining to be discovered.

The savannah honeybee, Apis mellifera scutellata Lepeletier (Hymenoptera: Apidae), is a eusocial insect that forages for nectar and pollen on a variety of flowering plants. However, it is selective of plants from which it forages. The preferred species are called bee-plants. The concept of bee-plants recognises that flowers do not have the same pollen and nectar value to honeybees. Thus, the strength of honeybee colonies is dependent on the presence of bee-plants throughout the year at any given locality. A study was conducted during March 2013–February 2015 to establish the presence of bee-plants and their phenology within 2 km radius of the apiary at ARC-Plant Protection Research Institute's farm in Rietondale, a suburb of Pretoria. A total of 247 flowering plant species from 70 families, comprising indigenous and exotic trees, shrubs and grasses, was recorded during March 2013–February 2014. Most plant species flowered during April, a smaller proportion during February and October, and only a few during June. Flowers of each plant species were sampled in order to make reference pollen grain slides. To determine bee-plants, a pollen trap was fitted to the entrance of one of five Langstroth hives on a fortnightly rotation during March 2014–February 2015 in order to intercept pollen pellets from the hind legs of returning foragers. A total of 2403 pollen pellets were recovered, most of which (1263) were collected during April and none during October. At the laboratory, about a quarter of each pellet was dissolved in distilled water and pollen grain slides were prepared. These slides were matched against reference pollen grain slides using a compound microscope. It was established that honeybees foraged from only 30 plant species. During summer (December–February), pollen was collected mostly from Persicaria capitata (Polygonaceae), Tithonia rotundifolia (Asteraceae) during autumn (March-May), Acacia galpinnii (Fabaceae) during winter (June–August), and Ageratum conyzoides (Asteraceae) during spring (September–November). These results show that honeybees had access to pollen sources that were sufficient to sustain their colonies throughout the year. As bee-plants were continuously available in the vicinity of the Rietondale farm, this site could be ideal for urban beekeeping.

Wolffia columbiana (Colombia watermeal), a naturalized American neophyte, is recorded for the first time from southern Europe. Identification, distribution, invasion status, ecology, and pathways of introduction are presented. Furthermore, the potential invasive behaviour and impacts in the new growing site have been assessed with the EPPO prioritization process scheme for invasive alien plants.

Plantago media, known as the hoary plantain, is a species of flowering plant in the plantain family Plantaginaceae that also was used as one of the Chinese herb in China. In this study, P. media ch...

Polyploidization, the increase in genome copies, is considered a major driving force for speciation. We have recently provided the first direct in planta evidence for polyspermy induced polyploidization. Capitalizing on a novel sco1-based polyspermy assay, we here show that polyspermy can selectively polyploidize the egg cell, while rendering the genome size of the ploidy-sensitive central cell unaffected. This unprecedented result indicates that polyspermy can bypass the triploid block, which is an established postzygotic polyploidization barrier. In fact, we here show that most polyspermy-derived seeds are insensitive to the triploid block suppressor admetos. The robustness of polyspermy-derived plants is evidenced by the first transcript profiling of triparental plants and our observation that these idiosyncratic organisms segregate tetraploid offspring within a single generation. Polyspermy-derived triparental plants are thus comparable to triploids recovered from interploidy crosses. Our results expand current polyploidization concepts and have important implications for plant breeding., eLife digest Ever since Darwin published his most famous book on the theory of evolution, scientists have sought to identify the mechanisms that drive the formation of new species. This is especially true for plant biologists who have long been fascinated by the extraordinary diversity of flowering plants. Many species of flowering plant first evolved after a dramatic increase in the DNA content of an individual plant, a process termed polyploidization. Most explanations for polyploidization involve a pollen grain making sperm that mistakenly contain two sets of chromosomes rather than one. Yet, it is difficult to reconcile this explanation with an important aspect of plant reproduction – the so-called “triploid block”. Fertilization in flowering plants is more complicated than in animals. While one sperm fertilizes the egg cell to make the plant embryo, a second sperm from the same pollen grain must fertilize another cell to form the endosperm, the tissue that will nourish the embryo as it develops. This means that sperm with twice the normal number of chromosomes would affect the DNA content of both the embryo and the endosperm. Yet, an endosperm that receives extra paternal DNA typically halts the development of the seed via a process known as the triploid block, meaning it was not clear how often this process would actually result in a polyploid plant. In 2017, researchers reported that plants can, on rare occasions, generate polyploid offspring via a different route: the fertilization of one egg with two sperm rather than one. Now, Mao et al. – who include several researchers involved in the 2017 study – show that this process, termed “polyspermy”, can introduce extra copies of DNA into just the egg cell, meaning it can bypass the triploid block of the endosperm. The experiments involved a model plant called Arabidopsis, and a screen of over 55,000 seeds identified about a dozen with embryos that had three parents, one mother and two fathers. Notably, most of these three-parent embryos developed in seeds that contained endosperm with the regular number of chromosomes and hence escaped the triploid block. These new results show that polyspermy provides plants with a means to essentially sneak extra copies of DNA ‘behind the back’ of the DNA-sensitive endosperm and into the next generation. They also give new insight in how polyploidization may have shaped the evolution of flowering plants and have important implications for agriculture where the breeding of new “hybrid” crops has often been limited by incompatibilities in the endosperm.

Asteraceae, the most successful flowering plant family, is adapted to the vast range of ecological niches. Their adaptability is partially based on their strong ability of reproduction. The initial, yet challenging, step for plant reproduction is to transport pollen to flower-visiting pollinators. Using quantitative experiments and numerical simulations, here we show that the common floral feature of Asteraceae, a pollen-bearing style, serves as a ballistic lever for catapulting pollen grains to pollinators. This is likely to be a pollination strategy to propel pollen to blind spots of pollinators’ bodies, which are beyond the physical reach of the styles. Our results suggest that the specific morphology and length of the floret, as well as the pollen adhesion, avoid pollen waste by catapulting pollen within a certain range equal to the size of a flowerhead. The insights into the functional floral oscillation may shed light on the superficially unremarkable, but ubiquitous functional floral design of Asteraceae.

Bromelia reversacantha Mez is an endemic species of the Cerrado Biome, for which there is no published data about its ornamental potentiality. The objective was to identify the ornamental and landscape potential of this bromeliad native from Cerrado. In September 2015, researchers specialized in the field of native plants evaluated the vegetative, reproductive and aesthetic characteristics of twenty plants of natural occurrence in the Biological Reserve Prof. José Ângelo Rizzo, in Mossâmedes, GO. In a scale of zero to ten, the bromeliad received an average score of 7.1 for the ornamental aspect, being 7.4; 7.3 and 6.6 respectively for the flowering plant, plant with fruits, and plant in the vegetative stage. The vigorous size, contrast, and color of the leaves and bracts, the showy inflorescence, the flowers, and fruits were shown as ornamental attributes. Bromelia reversacantha presents several characteristics favorable to its introduction in landscape projects, suggesting the use in gardens, or as living fences/borders and in pots; as well as in ornamentation in decorative arrangements with the use of inflorescences and fruit bunches. Resumo A Bromelia reversacantha Mez é uma espécie endêmica do Domínio Cerrado, para a qual não existem dados publicados sobre a sua potencialidade ornamental. Assim, objetivou-se identificar o potencial ornamental e paisagístico dessa bromélia nativa do Cerrado. Em setembro de 2015, pesquisadores especializados na área de plantas nativas avaliaram as características vegetativas, reprodutivas e estéticas de vinte plantas de ocorrência natural na Reserva Biológica Prof. José Ângelo Rizzo, em Mossâmedes, GO. Em escala de zero a dez, a bromélia recebeu nota média de 7,1 quanto ao aspecto ornamental, sendo de 7,4; 7,3 e 6,6 respectivamente para a planta florida, com frutos, e em estádio vegetativo. O porte vigoroso, o contraste e a coloração das folhas e brácteas, a inflorescência vistosa, as flores e frutos mostraram-se como atributos ornamentais. A Bromelia reversacantha apresenta várias características favoráveis à sua introdução em projetos paisagísticos, sugerindo o uso em jardins, ou ainda como cercas vivas/bordaduras e em vasos; assim como na ornamentação em arranjos decorativos com o uso das inflorescências e cachos de frutos.

The delicate necklace of threaded petals from the tomb of Rameses II, midnineteenth century glass houses built for the newly discovered Victoria amazonica , and Monet’s giant canvases in the Musee de l'Orangerie all testify to a deep human attraction to water lilies: beguiling plants with showy flowers that seem to arise nymph-like out of the mud. Like orchids, cacti, succulents, and carnivorous plants, water lilies have a dedicated band of horticulturalists devoted to growing and exploring their endless variety. The late nineteenth century craze for water lilies that attracted Monet was fueled by one such enthusiast, Joseph Bory Latour-Marliac (1), who developed hardy water lily cultivars with dazzling new flower colors ranging from “delicate yellow to fuscia and deep red.” Nymphaea thermarum , the focus of the recent paper by Povilus et al. (2), is another unusual water lily variant. The smallest water lily known, N. thermarum was discovered and described in the late 1980s (3). Endemic to hot spring lakes in the Albertine Rift Valley of Rwanda, now, just a few decades after its discovery, it appears to be extinct in the wild (4, 5). Crucially, as recognized by Povilus et al. (2), it has a small genome, only about three times larger than that of the botanical model of choice, Arabidopsis. Povilus et al. (2) provide initial documentation of that genome and use it to explore the genomic correlates and evolutionary significance of an unusual water lily trait, the complete loss of the vascular cambium that is responsible for the formation of woody tissues in almost all seed plants. Part of the interest in water lilies for Povilus et al. (2), and for contemporary plant science, flows from the phylogenetic position of water lilies in flowering plant (angiosperm) evolution. It has long been suspected that … [↵][1]1To whom correspondence may be addressed. Email: peter.crane{at}yale.edu. [1]: #xref-corresp-1-1

Laticifer cells are specialized plant cells that synthesize and accumulate latex. In fact, latex-bearing plants are only found in about 10% of flowering plant species, but many of them contain high-value secondary metabolites. In this review, we summarize the characteristics of latex-bearing plants. Additionally, the synthetic pathway and genes of secondary metabolites in Macleaya cordata and Cannabis sativa are described in detail.

Ravenala palm (Ravenala madagascariensis) also known as Traveler’s palm, is a tree native to Madagascar and a member of the monocotyledonous flowering plant family Strelitziaceae. This family is not in true sense a palm family, but they share some common characters with palms. Ravenala palm is preferred among ornamental perennials due to its aesthetic beauty. However, unlike other palms, it is susceptible to various pathogenic fungi that are cause of wilts, leaf spots and sooty blotches. This chapter will discuss the major fungal pathogens of Ravenala palm, their etiology and management strategies.