Search

The diversification of angiosperms has largely been attributed to adaptive radiation of their pollination and mating systems, which are relevant drivers of the macroevolution processes. The fig (Ficus, Moraceae) and fig wasp (Agaonidae, Hymenoptera) interaction is an example of obligate mutualism. Passive and active pollination modes have been associated with morphological traits in both partners. However, more information is required to assess the relationship between floral traits and pollination modes, particularly in Neotropical Ficus species.This study evaluates the morphological traits of figs and fig wasps regarding pollination modes in species belonging to Neotropical Ficus sections (three species each of Americanae and Pharmacosycea). Pollination mode was identified by floral morphology, anther/ovule ratio, and specialized structures fig wasps use for pollen transport (pollen pocket and coxal combs).Fig species in sect. Americanae are actively pollinated because pistillate flowers form a synstigma, present anther/ovule ratios <0.11, and their pollinator Pegoscapus fig wasps have pollen pockets and coxal combs. In contrast, species in sect. Pharmacosycea have free pistillate flowers, with anther/ovule ratios >0.27; they are pollinated by Tetrapus wasps, which lack specialized structures to carry pollen. Each species of Ficus was associated with a single morphospecies of fig wasp.The results support previous contributions that consider reciprocal morphological traits between fig species and their pollinating wasps as evidence of a close co‐evolutionary history. [ABSTRACT FROM AUTHOR]

Liparis gigantea generally grows in subtropical broad-leaved evergreen forests and blooms during the rainy season with purple flowers. Our study focused on floral phenology and morphology, pollinators and their behavior, and pollination mechanism. Our observations showed that the population flowering period lasted for about 20 days, and the single flowering period was 5–6 days. The rate of artificial self-pollination was 100%, which indicated that L. gigantea was self-compatible. L. gigantea achieved reproduction success by attracting Mycomya sp. (Diptera, Mycetophilidae). There was no significant difference between pollination efficiency both at night and during the day (Premoval = 0.34, Pdeposition = 0.55). Data on the functional morphological characteristics of L. gigantea and the pollinators related to pollination showed a high match, with the height and width of the pollination tunnel were 3.10 ± 0.34 and 1.93 ± 0.22 mm, and the height and width of the pollinator's thorax were 5.84 ± 0.96 and 0.96 ± 0.23 mm. The forefoot of insects could be stretched and bent when visiting flowers, so that they could exactly enter and exit the flower with removing or depositing pollinia. While L. gigantea could be pollinated by Mycomya sp., it could also be self-pollinated with the aid of rain. With the assistance of raindrops, the pollinia of L. gigantea slowly slid to the stigma. And this rain-assisted self-pollination mechanism guaranteed the success of reproduction in L. gigantea, especially in the special habitat and flowering season. The results of our study indicated that L. gigantea had a complex pollination reproduction system for insect and rain pollination. [ABSTRACT FROM AUTHOR]

The c. 270 endemic species of Pedicularis in the Himalaya–Hengduan Mountains (HHM) region exhibit high diversity in geographic distribution, elevational range and floral morphology. Many of these, including the species with the longest corolla tubes and beaked galeas, are monophyletic and represent a putative in situ radiation. In this study, we focus on the representative Clade 3 within the HHM region. We integrate the plastid phylogeny of this clade with environmental data and species distributions to infer environmental correlates of species diversity. We estimate macroevolutionary rates and reconstructed ancestral states for geographic ranges and corolla traits, and analyse patterns of range overlap and niche evolution to assess drivers of diversification in the HHM region. Our results show that the region from northwest Yunnan to southwest Sichuan is the centre of diversity for this clade of Pedicularis. Rates of diversification are associated with precipitation and multiple environmental factors. Multiple range expansions from the Sanjiang (Three Parallel Rivers) region, followed by allopatric speciation across the HHM region, contributed to early rapid diversification. Corolla traits are not significantly associated with species diversification. This study highlights the importance of integrated evidence for understanding species diversification dynamics and contributes to our understanding of the origins of the remarkable richness of plant species in the HHM region. [ABSTRACT FROM AUTHOR]

Background: Flower morphology is believed to be primarily shaped by the most important pollinators when more than one pollinating species visits the flowers. However, floral adaptation to the selection mediated by multiple pollinators has received little attention. The plant Stellera chamaejasme has evolved a pollination syndrome matching both lepidopteran and thrips. In this study, to test the relative importance of different pollinators to the plant's reproductive success and clarify how phenotypic selection on floral traits relates to different functional groups of pollinators, we determined the relative contributions of different pollinating insects to plant reproductive fitness through pollinator manipulation experiments and investigated the associated phenotypic selection on floral traits. Results: Lepidopterans and thrips had comparable contributions to the reproductive fitness of S. chamaejasme. Among lepidopterans, the fitness contribution was distinctly higher for moths than for butterflies. Corolla opening size (i.e., corolla entrance) was subject to positive directional selection mediated mainly by lepidopterans, with thrips exerting opposing directional selection for this trait. The significant correlational selection between tube length and corolla opening size suggested that thrips and lepidopteran pollinators favored either the broad-entranced short flowers or the narrow-entranced long flowers. Conclusions: Most likely, a functionally integrated adaptation to accommodate a variety of pollinators led to the floral design of S. chamaejasme, which in turn contributed to the diversity of flowers. Clinical trial number: Not applicable. [ABSTRACT FROM AUTHOR]

Summary Adaptive radiation in Ophrys orchids leads to complex floral phenotypes that vary in scent, color and shape. Using a novel pipeline to quantify these phenotypes, we investigated trait divergence at early stages of speciation in six populations of Ophrys aveyronensis experiencing recent allopatry. By integrating different genetic/genomic techniques, we investigated: variation and integration of floral components (scent, color and shape); phenotypes and genomic regions under divergent selection; and the genomic bases of trait variation. We identified a large genomic island of divergence, likely associated with phenotypic variation in particular in floral odor. We detected potential divergent selection on macular color, while stabilizing selection was suspected on floral morphology and for several volatile olfactive compounds. We also identified candidate genes involved in anthocyanin and in steroid biosynthesis pathways associated with standing genetic variation in color and odor. This study sheds light on early differentiation in Ophrys, revealing patterns that often become invisible over time, that is the geographic mosaic of traits under selection and the early appearance of strong genomic divergence. It also supports a crucial genomic region for future investigation and highlights the value of a multifaceted approach in unraveling speciation within taxa with large genomes. [ABSTRACT FROM AUTHOR]

The New Zealand Institute for Plant and Food Research has developed three semi-dwarfing apple rootstocks: PFR2, 4 and 5 with pest and disease resistance/tolerance. Nursery performance and flowering of ‘Scilate' and ‘Fuji Supreme' grafted onto PFR rootstocks and grown as monoaxis or biaxis trees were evaluated in comparison with ‘Malling 9' (dwarf) and ‘G.202' (semi-dwarf) at Hawkes' Bay research centre. For monoaxis ‘Scilate' trees, PFR rootstocks promoted primary, axillary and total shoot length/scion by (11–15%), (54–76%) and (22–37%), respectively compared with ‘M.9', but the same were lower by (4–11%), (25–62%) and (17–42%) compared with ‘G.202'. On PFR2 and PFR5, ‘Scilate' produced 6 axillary shoots/tree, compared with ‘M.9' (4) and ‘G.202' (7). ‘Scilate' on PFR2, 4 and 5 produced 74%, 62% and 93% of axillary shoots with moderate (30°–45°) crotch angle compared with ‘M.9' (30%) and ‘G.202' (79%). On biaxis trees, the total shoot length was higher on PFR2, 4 and 5 compared with ‘M.9', but not different from ‘G.202'. Flowering precocity was not affected by rootstocks. Overall, PFR2, 4, 5 and ‘G.202’ produced high-grade young trees expressing greater potential for early canopy development. [ABSTRACT FROM AUTHOR]

Jasmine flowers (Jasminum sambac) are very popular in Indonesia and Asia because of their strong sweet fragrance. Jasmine flowers have been used to decorate weddings, houses of worship, and festivals and are included in aromatic products like candles, perfumes, soaps, and lotions. Despite its popularity, studies on morphology, growth, and flowering characteristics of various jasmine species are lacking. Our study aims to describe the morphology and flowering of jasmine cultivars from a relatively humid environment, Java Island (Emprit Bandar Arum), and a relatively drier environment, Madura Island (Ratoh Ebuh), Indonesia. Each cultivar has seven blocks of four plants each block. The study was conducted at Cikabayan, West Java, Indonesia, from April 2022 to February 2023. Java and Madura’s jasmine have morphological similarities in their stem shape and color, leaf type, shape and arrangement, calyx structure, petal shape, and flower color. The two jasmine species differ in leaf size, leaf tip shape, stomatal size and density, and duration from floral bud initiation to anthesis. Madura jasmines produced about 20% more flowers than Java jasmines. Understanding the morphology and flowering of different types of jasmine is important to correctly identify the jasmine cultivars to determine the peak flowering season and flower production. A list of characters that can potentially be used for future studies of the two jasmine cultivars was described. The results of this study would benefit commercial growers in choosing the right type/cultivar to grow and predicting the time to harvest the flowers in a particular region. [ABSTRACT FROM AUTHOR]

Floral syndromes can be a useful tool for predicting the identity of pollinators from floral morphology. However, the reliability of floral syndromes are still debated in the literature, and can often result in effective pollinators being overlooked. Pollination by moths has historically been associated with a floral syndrome comprising white tubular flowers that are heavily scented at night, but there have been few experimental tests of this association. To test whether moths preferentially land on flowers that are white and tubular, we allowed two moth species (Agrotis ipsilon (Hufnaggel, 1766) and Ichneutica mutans (Walker, 1857)) to choose freely between three plant species (Vaccinium corymbosum, Ericaceae, Pittosporum tenuifolium, Pittosporaceae, and two forms of Leptospermum scoparium, Myrtaceae) which represent four different floral morphologies. Anthers on the flowers were marked with fluorescent powder dye (pollen‐tracker), with the presence of pollen‐tracker on moth bodies after the experiment indicating floral visitation. We detected no floral preferences for any of the plant species by either moth species, suggesting moths will visit flowers that lack features associated with the syndrome even when in the presence of white, tubular flowers which might be predicted to be more attractive to moths. We also examined moth bodies to determine where pollen‐tracker was carried most often and if this varied among the floral types. Our results indicate that some moth body parts may be more important than others for pollen transfer, depending on the morphology of the flowers visited. After visiting tubular flowers (Vaccinium and Pittosporum), pollen‐tracker was most often located on the proboscis, but after visiting open‐access flowers (Leptospermum) pollen‐tracker was most often located on the legs. Future studies looking at the presence of pollen on moth bodies should consider this and ensure the entire moth body is examined for the presence of pollen. [ABSTRACT FROM AUTHOR]

Within‐flower self‐pollination should be the major source of self‐fertilization in mixed‐mating species that present single or few flowers simultaneously. It is also an often unmeasured source of selfing in species with many flowers open simultaneously. In self‐compatible species in which pistil and stamen numbers vary, the rate of within‐flower selfing should depend on the number of pistils and stamens, the timing of flowering and the morphology of subsidiary floral traits. The intensity and direction of selection on these traits should thus also depend on the level of inbreeding depression.Here, we measured the dependence of the within‐flower selfing rate on floral sex allocation, phenology, petal length and floral stalk height in a population of the perennial herb Pulsatilla alpina (Ranunculaceae) in which most individuals had single flowers. We estimated inbreeding depression in the population by comparing inbreeding coefficients between parents and seed progeny using microsatellite markers. We then estimated selection on the measured traits via female reproductive success at the flower level and compared our estimates with a hypothetical scenario in which inbreeding depression was assumed to be absent.Inbreeding depression was estimated to be severe (0.95). The within‐flower selfing rate varied widely among flowers and depended positively on stamen number and negatively on pistil number and flowering date, supporting the predictions of a mass‐action model. The dependence of the selfing rate on the measured floral traits consistently predicted (non‐linear) patterns of selection under high inbreeding depression that were distinct from those under a hypothetical scenario of no inbreeding depression.Synthesis. While previous research has emphasized the importance of mass‐action mating on selfing among flowers of plants with large floral displays, our results demonstrate its importance for selfing within individual flowers. They also demonstrate the importance of accounting for both the selfing rate and inbreeding depression when inferring selection on floral and other traits via female fitness. [ABSTRACT FROM AUTHOR]

• Ethephon and NAA applications resulted in dense bisexual flowers within the first four weeks of the flowering period. • NAA applications improved yield and fruit size. • Applications during the 'green leaf' stage increased the yield per tree and fruit size. • A positive correlation was observed between the number of bisexual flowers and yield per tree. The study aimed to determine the effects of ethephon (150 μL/L, 200 μL/L, and 250 μL/L) and 1-naphthalene acetic acid (NAA; 50 μL/L, 100 μL/L, and 150 μL/L) applications at 'red leaf' and 'green leaf' stages on bisexual flower, fruit yield and quality characteristics of 'Hicaznar' cultivar. These results showed that ethephon and NAA applications increased the bisexual flower and fruit set ratios, depending on the used dose. The applications formed dense bisexual flowers in the first four weeks of the flowering period. The highest yield per tree and hectare was obtained from applying 50 μL/L NAA at the 'green leaf' stage for two consecutive years. Pomegranates harvested from ethephon and NAA-treated plants exhibited increased fruit size and seed percentage compared to those from control plants. Overall, this study demonstrated the potential of ethephon and NAA treatments to improve fruit yield and quality in pomegranate. [ABSTRACT FROM AUTHOR]

Male sterility is a common phenomenon in higher plants and often plays an important role in the selection of superior offspring. 'Xiang Yun' is a mutant of Lagerstroemia indica that does not bear fruit after flowering, and its flowering period is significantly longer than that of normal L. indica. To explore the timing and molecular mechanisms of sterility in 'Xiang Yun', this study determined the period of sterility through anatomical observation and compared the content of nutrients and the activity of antioxidative enzymes at different stages of flower development. Finally, sequence alignment and qPCR were used to analyze the differences in pollen development genes between 'Xiang Yun' and 'Hong Ye'. The results showed that the anthers of 'Xiang Yun' dispersed pollen normally, but the pollen grains could not germinate normally. Observations with scanning electron microscopy revealed that the pollen grains were uneven in size and shriveled in shape. Further observation of anther sections found that abnormal development of the microspores began at the S2 stage, with the callose wall between microspores of 'Xiang Yun' being thicker than that of 'Hong Ye'. In addition, during the flower development of 'Xiang Yun', the contents of soluble sugar, soluble protein, free proline, and triglycerides were deficient to varying degrees, and the activities of POD, SOD, and MDA were lower. Sequence alignment and qPCR showed that there were several mutations in EFD1, TPD1, and DEX1 of 'Xiang Yun' compared with 'Hong Ye', and the expression levels of these genes were abnormally elevated in the later stages of development. Our results clarified the timing and phenotype of male sterility in 'Xiang Yun'. This provides solid and valuable information for further research on the molecular mechanism of sterility in 'Xiang Yun' and the genetic breeding of crape myrtle. [ABSTRACT FROM AUTHOR]

R2R3-MYBs are an important group of transcription factors that regulate crucial developmental processes across the plant kingdom; yet no comprehensive analysis of the R2R3-MYBs in the early-diverging eudicot clade of Ranunculaceae has been conducted so far. In the present study, Aquilegia coerulea is chosen to understand the extent of conservation and divergence of R2R3-MYBs as a representative of the family by analysing the genomic distribution, organization, gene structure, physiochemical properties, protein architecture, evolution and possible mode of expansion. Genome-wide analysis showed the presence of 82 putative homologues classified into 21 subgroups, based on phylogenetic analysis of full-length protein sequences. The domain has remained largely conserved across all homologues with few differences from the characterized Arabidopsis thaliana R2R3-MYBs. The topology of the phylogenetic tree remains the same when full-length protein sequences are used, indicating that the evolution of R2R3-MYBs is driven by the domain region only. This is supported by the presence of similar structures of exon–intron and conserved motifs within the same subgroup. Furthermore, comparisons of the AqcoeR2R3-MYB members with monocots and core-eudicots revealed the evolutionary expansion of a few functional clades, such as A. thaliana R2R3-MYB subgroup 6 (SG6), the upstream regulatory factors of floral pigment biosynthesis and floral color. The reconstructed evolutionary history of SG6-like genes across angiosperms highlights the occurrence of independent duplication events in the genus Aquilegia. AqcoeR2R3-MYB genes are present in all seven chromosomes of A. coerulea, most of which result from local and segmental duplications. Selection analysis of these duplicated gene pairs indicates purifying selection except one, and the physiochemical analyses of R2R3-MYBs reveal differences among the MYBs signifying their functional diversification. This study paves the way for further investigation of paralogous copies and their probable role in the evolution of different floral traits in A. coerulea. It lays the foundation for functional genomic studies of R2R3-MYBs in the basal eudicots and facilitates comparative studies among angiosperms. The work also provides a framework for deciphering novel genetic regulatory pathways that govern the diversity of floral morphology. [ABSTRACT FROM AUTHOR]

Background: Synchronopatric plant species, coexisting and flowering simultaneously, often engage in intense competition for pollen deposition on shared pollinators. This study focuses on the intricate dynamics of chiropterophilous flowers within the neotropical bat-pollination plant guild, specifically investigating the mechanical fit of reproductive structures to pollinating bats at the community level. Methods: Utilizing a diverse guild of bat-pollinated plant species from the Caatinga, the largest dry forest in the Neotropics, our research integrates various key components. Initially, we identified specific contact sites for floral reproductive structures on the bat's body, exploring diverse pollen placement strategies. Subsequent efforts involved characterizing floral traits within the guild and examining their associations with different pollen placement strategies. Precision in the contact of floral reproductive structures was estimated, and findings were integrated by associating pollen placement strategies and precision with the investment in pollen production. Results: We found that certain bat body parts, particularly the face and neck, were more frequently contacted by reproductive structures. The three identified categories of pollen placement strategies were evenly distributed among plant species, each linked to specific floral traits. Notably, the absence of oriented herkogamy prevailed in 70% of the species. Morphometric analyses unveiled significant variations in operative distances among species, emphasizing exceptional variability in certain outliers. While precision in pollen transfer was influenced by key factors, surprisingly, investment in pollen production did not differ among plants with distinct pollen placement strategies. Furthermore, it showed no correlation with fundamental accuracy. Conclusions: The subsequent exploration delves into the intricate associations between distinct floral characteristics and various pollen placement strategies, shaping the complex pollen landscape on bat bodies. This research provides valuable insights into the community-level dynamics of chiropterophilous flowers in the Caatinga Dry Forest, emphasizing the role of different pollen deposition strategies in facilitating the coexistence of multiple plant species within the chiropterophilous guild. [ABSTRACT FROM AUTHOR]

Premise: Plants generate a wide array of signals such as olfactory cues to attract and manipulate the response of pollinators. The present study addresses the temporal patterns of scent emission as an additional dimension to the scent composition. The expectation is that divergent floral function is reflected in divergent qualitative and temporal emission patterns. Methods: We used GC‐ion mobility spectrometry with an integrated pre‐concentration for automated acquisition of the temporal trends in floral volatile emissions for N. viridiflorus, N. papyraceus, and N. cantabricus subsp. foliosus. Results: We found a considerable increase in scent emissions and changes in scent composition for N. viridiflorus at night. This increase was particularly pronounced for aromatic substances such as benzyl acetate and p‐cresol. We found no diurnal patterns in N. papyraceus, despite a similar qualitative composition of floral volatiles. Narcissus cantabricus subsp. foliosus showed no diurnal patterns either and differed considerably in floral scent composition. Conclusions: Scent composition, circadian emission patterns, and floral morphology indicate divergent, but partially overlapping pollinator communities. However, the limited pollinator data from the field only permits a tentative correlation between emission patterns and flower visitors. Narcissus papyraceus and N. cantabricus show no clear diurnal patterns and thus no adjustment to the activity patterns of their diurnal pollinators. In N. viridiflorus, timing of scent emission indicates an adaptation to nocturnal flower visitors, contradicting Macroglossum as the only reported pollinator. We propose that the legitimate pollinators of N. viridiflorus are nocturnal and are still unidentified. [ABSTRACT FROM AUTHOR]

Petunia stands as the top-selling bedding plant in the U.S., and improved lighting control in greenhouses holds the potential to reduce crop production time and optimize crop quality. This study investigated the impact of four distinct daily light integral (DLI) conditions with and without supplemental far-red (FR) radiation on the growth of petunia liners and subsequent development of finish plants. Two experiments were conducted in spring (9 April to 18 June 2021) and winter (28 October 2021 to 6 January 2022). Petunia cuttings were rooted in a common environment and then transferred to four greenhouse sections with different DLI treatments: 6, 9, 12, and 15 mol·m−2·d−1 for four weeks. Within each DLI condition, half of the plants were exposed to 28 μmol·m−2·s−1 supplemental FR radiation for 16 h daily (equivalent to 1.61 mol·m−2·d−1 light integral). The number of flower buds and open flowers were tracked daily. Representative liners were destructively harvested and evaluated after four weeks of lighting treatments. The remaining plants were transplanted and moved to a common DLI condition of 15 mol·m−2·d−1 for an additional three weeks before being destructively harvested and evaluated as finish plants. The primary finding reveals the promoting effect of DLI on flowering, branching, morphology, and biomass accumulation of petunia liners, with many effects persisting into the finish stage. A threshold DLI of 9 mol·m−2·d−1 was identified, as lower DLI (6 mol·m−2·d−1) resulted in extensive stem elongation, rendering the plants unmarketable. Higher DLI levels were found to be optimal in terms of flowering and morphology. Supplemental FR accelerated flowering by up to three days in the summer experiment and up to 12 days in the winter experiment. However, FR had limited impact on the number of flower buds and open flowers, branching, and shoot and root weight of the finish plants. Interactions between DLI and FR were observed on some parameters, whereby FR effects were more pronounced under lower DLI. Overall, both higher DLI and supplemental FR exhibited beneficial effects, but DLI had a more pronounced effect. Thus, DLI during petunia liner production appears more important than adding FR. This study well simulated the commercial propagation and production of petunia plants, providing practical insights for decision-making regarding lighting strategies. [ABSTRACT FROM AUTHOR]

[Objective] This study explored the cytological characteristics of different developmental stages of Prunus sibirica microspores and revealed the relationships between microspore periods and floral organ morphology to provide basis for reproductive biology research and germplasm innovation of Prunus sibirica. [Method] The flower buds of male sterile and fertile lines of Prunus sibirica were selected as the research subjects. The paraffin section technique and modified carmine acetate staining technique were used to observe morphology of microspores at various development stages. Phenotypic observation and analysis of flower organ morphology were also conducted during corresponding periods. [Result] The microspore development periods of Prunus sibirica included tetrad stage, microspore period and mature stage. The microspore period included uninucleate stage (early-uninucleate stage, mid-uninucleate stage, late-uninucleate stage) and binucleate stage (early-binucleate stage, middle-binucleate stage, late-binucleate stage) with distinct cytological features in each stage. In the early-binucleate stage, the microspores of the male sterile line were abnormal due to the failure to complete mitosis, but there was no abnormality in the development of floral organs. The bud transverse diameter, bud longitudinal diameter, anther transverse diameter and anther longitudinal diameter gradually increased with the advance of microspore development stage in Prunus sibirica. There were corresponding relationships between microspore periods and morphological characteristics of floral organs. The bud transverse diameter, anther transverse diameter and anther longitudinal diameter were utilized to differentiate microspores between various microspore stages ranging from early-binucleate stage to late-binucleate stage. The color of calyx was employed to differentiate microspores between mid-uninucleate stage and late-uninucleate stage. Additionally, microspore diameter distinguished different stages of microspores from early-uninucleate stage to early-binucleate stage. At the early-binucleate stage, bud transverse diameters of male sterile line and male fertile line in Prunus sibirica were 3.36 and 3.34 mm, respectively. The anther longitudinal diameters of male sterile line and male fertile line were 0.95 and 0.96 mm, respectively. The anther transverse diameters of male sterile line and male fertile line were both 0.73 mm. The microspore diameter of male sterile line and male fertile line were both 28.90 μm. [Conclusion] The microspore period of Prunus sibirica was correlated with bud transverse diameter, anther transverse diameter, anther longitudinal diameter, and calyx color, which could be used as an important basis for dividing microspore stages. [ABSTRACT FROM AUTHOR]

Abstract Background Synchronopatric plant species, coexisting and flowering simultaneously, often engage in intense competition for pollen deposition on shared pollinators. This study focuses on the intricate dynamics of chiropterophilous flowers within the neotropical bat-pollination plant guild, specifically investigating the mechanical fit of reproductive structures to pollinating bats at the community level. Methods Utilizing a diverse guild of bat-pollinated plant species from the Caatinga, the largest dry forest in the Neotropics, our research integrates various key components. Initially, we identified specific contact sites for floral reproductive structures on the bat's body, exploring diverse pollen placement strategies. Subsequent efforts involved characterizing floral traits within the guild and examining their associations with different pollen placement strategies. Precision in the contact of floral reproductive structures was estimated, and findings were integrated by associating pollen placement strategies and precision with the investment in pollen production. Results We found that certain bat body parts, particularly the face and neck, were more frequently contacted by reproductive structures. The three identified categories of pollen placement strategies were evenly distributed among plant species, each linked to specific floral traits. Notably, the absence of oriented herkogamy prevailed in 70% of the species. Morphometric analyses unveiled significant variations in operative distances among species, emphasizing exceptional variability in certain outliers. While precision in pollen transfer was influenced by key factors, surprisingly, investment in pollen production did not differ among plants with distinct pollen placement strategies. Furthermore, it showed no correlation with fundamental accuracy. Conclusions The subsequent exploration delves into the intricate associations between distinct floral characteristics and various pollen placement strategies, shaping the complex pollen landscape on bat bodies. This research provides valuable insights into the community-level dynamics of chiropterophilous flowers in the Caatinga Dry Forest, emphasizing the role of different pollen deposition strategies in facilitating the coexistence of multiple plant species within the chiropterophilous guild.

Hybridization between rare and widespread species can result in loss of genetic integrity for the rarer species, which can have management and conservation implications. One rare species, Phlox hirsuta, is a serpentine endemic in northern California, and it frequently co‐occurs with a widespread congener, Phlox speciosa. Putative hybrids were recognized based on intermediate morphology, so the possibility of hybridization was explored using floral morphological and molecular data. Ninety‐eight individuals of P. hirsuta and P. speciosa were collected from each of three sites, and floral features were measured and compared. Eleven microsatellite loci were amplified for species and putative hybrids, and inter‐ and intraspecific genetic diversity and relationships were investigated with multiple methods. Variation in morphological and molecular data was recovered. Floral variation was greater for P. hirsuta than P. speciosa. Putative hybrids were genetically allied with P. speciosa, but two individuals of P. hirsuta were resolved to have genetic similarity with P. speciosa. While hybridization is possible between the species, it is uncommon and appears to be primarily unidirectional. The small number of recognized hybrids may be due to ineffective interspecific pollination, hybrids being less fit than parents, and/or small sample sizes. Reinforcement does not appear to play a role in secondary contact between species. Both microsatellite loci and floral morphology varied across the small geographic range of P. hirsuta, suggesting local differentiation and adaptation are possible over short distances. [ABSTRACT FROM AUTHOR]

Species traits greatly influence interactions between plants and pollinators where floral nectar is the primary energy source fostering this mutualism. However, very little is known about how nectar traits mediate interactions in pollination networks compared with morphological traits. Here, we evaluated the role of morphological and nectar traits in shaping plant–hummingbird interaction networks along an elevation gradient. For this, we assessed patterns in floral phenotypic traits and network properties of plant species across elevations in Costa Rica. We also analysed whether plant species with generalized flower traits are ecological generalists and how morphological trait matching versus nectar traits affect interactions. We found marked variation in floral phenotypic traits and flower abundance of hummingbird-visited plant species across 10 sites along the elevation gradient. We did not find evidence for a relationship between flower morphology and nectar traits or between morphological and ecological generalization of plant species. Plant–hummingbird interaction frequency increased when the lengths of hummingbird bill and flower corolla were similar, indicating morphological matching, whereas nectar traits were unrelated to interactions. While nectar may play a difficult-to-detect secondary role within plant–hummingbird networks, our results reinforce the idea that morphological matching is an important factor in structuring ecological communities. [ABSTRACT FROM AUTHOR]

[Objective) The paper aimed to explore the biological characteristics of flowering and pollination of Annona squamosa L., to lay the foundation for the study of the reproductive breeding system of A. squamosa, and also for the hybrid breeding and production of A. squamosa to provide a theoretical basis. (Method) A. squamosa varieties Damu, Gefner and AP were taken as the objects of study, and its flower morphology and flowering process were observed, using scanning electron microscopy to observe the pollen morphology, and its visiting and pollinating insects were investigated; Rate of pollen germination, stigma pollination at different flowering processes were determined, and artificial pollination comparison test was conducted, fruit setting rate and fruit characteristics were recorded and analyzed. (Result)] A. squamo-sa flowers were green with a special structure, the pollination chamber was semi-closed and the main pollinating insects were small beetles and thrips. The pollen was tetrads, radially symmetrical, with a reticulated carved pattern on the outer wall, with crisscrossed patterns on the ridges of Damu, and inconspicuous dotted projections on the ridges of Gefner and AP. The pollen had some vigour before flowering, then pollen vigour increased over time, reaching a maximum at the pollen scattering period, then declined, stigma was pollenable at the unopened period, and stigma pollenability was still strong at initial opening to fully open period, and stigma pollenability was weak at pollen scattering period. The fruit setting rate of artificial pollination was 74.67% and that of natural pollination was 32.22%. There was no significant difference in the quality of fruits between different pollination methods (P>0.05, the same as below), and the fruits of artificial pollination had better fruit shape and greater values of single fruit weight, longitudinal and transverse diameters, number of seeds, and edible rate. Vitamin C, soluble sugar, protein, total acid, total phenols, total flavonoids, total amino acids contents as well as potassium, calcium, sodium, magnesium, iron, manganese, zinc elements contents did not differ significantly from the contents of naturally pollinated fruits. [Conclusion] The flowers of A. squamosa are heteroecious, with semi-closed pollination chambers. The main pollinating insects are small beetles and thrips. The fruit setting rate of the artificial pollination treatment is significantly higher than that of the natural pollination treatment, and the fruit quality is similar to that of the natural pollination treatment, but with better fruit shape. [ABSTRACT FROM AUTHOR]

Flowers of Salvia are characterized by a diversity of staminal lever types mediating pollen transfer. In the East Asian subgenus Glutinaria, species have been categorized based on their distinct flower and stamen morphologies. A hypothesized advantage of degraded-lever types suggests they may optimize pollinator foraging time, increase visitation rates, and potentially trigger autonomous self-pollination. However, this hypothesis remains untested. Here, Salvia castanea, S. miltiorrhiza, and S. liguliloba were selected as test species representing the three major flower and stamen types of the East Asian sages. We compared the species with regard to their inflorescence architecture, floral display, nectar reward, pollinator efficiency, and seed set. We found that S. liguliloba had a degraded-lever type that significantly reduced pollinator foraging time did not significantly increase pollination efficiency. These species have a mixed mating pattern with high seed set, no pollen- or pollinator limitation, and no inbreeding depression. We conclude that the diversity of floral traits is addressed to pollinators, whereas reproductive success emerges from a complex interplay of factors encompassing floral characteristics, pollination efficiency, plant life history, or/and other biotic and abiotic factors. For this reason, the link between floral morphological traits and mating systems should not overestimated. [ABSTRACT FROM AUTHOR]

Previous studies on the mountain plant Ranunculus kuepferi concluded that apomictic self-compatible tetraploids have experienced a niche shift toward a colder climate during the Holocene, which suggests a fitness advantage over the sexual, self-sterile diploid parents under cold and stressful high-mountain conditions. However, there is still a lack of information on whether reproductive development would be advantageous for tetraploids. Here, we report on microsporogenesis, megagametogenesis, the dynamics of flower and seed development, and the consequences for reproductive success in a common garden experiment along a 1000 m climatic elevation gradient and in natural populations. Flower buds were initiated in the year preceding anthesis and passed winter in a pre-meiotic stage. Flower morphology differed in the known cytotype-specific way in that tetraploid flowers produced about twice as many carpels and fewer petals, stamens, and pollen grains than diploid flowers. Tetraploids developed precociously aposporous embryo sacs and showed a high rate of developmental disturbances. Sexual seed formation prevailed in diploids and pseudogamous apomixis in tetraploids. Along the elevation gradient, stigma pollen load, pollen performance, and seed output decreased. Combinations of reproductive traits, namely, bypass of meiosis irregularities and uniparental reproduction, might have promoted the vast expansion of apomictic R. kuepferi lines across the European Alps. [ABSTRACT FROM AUTHOR]

Nerium oleander is a popular shrub because of its drought-tolerant capacity and least susceptibility to pests and diseases. Despite its widespread cultivation in tropical and subtropical regions, there has been a lack of information on the performance of different genotypes regarding growth and yield parameters. The present study aimed to assess the performance of ten different Nerium genotypes for growth and yield traits. Genotypes were procured from various nurseries in the suburbs of Bengaluru. The collection of genotypes was based on flower morphology, flower colour, the stature of plants, and leaf variegation. A randomised complete block design with three replications was used and 1.2 m × 1.2 m spacing was followed throughout January 2018 to April 2019. The observations were made every 60 days up to 300 DAP (Days After Planting), and there were notable variations in the growth and yield metrics of the genotypes. Five tagged plants in each replication were used to record all observations. Genotype BNC-1 (Bengaluru Nerium Collection- 1) recorded the highest value for plant height (107.33 cm), plant spread (1770.66 cm2), chlorophyll (1.16 mg/g) as well as yield of flower per plant and per hectare (1.85 kg and 12.73 t respectively) while genotype BNC-6 (Bengaluru Nerium Collection- 6) recorded the highest number of branches (45.00). The lowest flower yield per plant and hectare was observed in BNC-6 (0.32 kg and 2.26 t, respectively). In conclusion, genotype BNC-1 exhibits characteristics warranting its consideration for cultivation and inclusion in breeding programs aimed at varietal development. [ABSTRACT FROM AUTHOR]

Floral diversity of Croton, the second largest genus in Euphorbiaceae, is currently under-explored. Several clades demonstrate an unusual floral morphology, e.g., lower or higher stamen number, bilateral symmetry and reduced ovary, but have never been investigated in a comparative study with typical Croton. This study examined morphology and ontogeny of flowers in nine Croton species from different clades within the genus with light and scanning microscopy, resin sectioning and micro-computed tomography. In staminate flowers, great variations of stamen number and arrangement are observed. The ancestral androecium likely consisted of two or more whorls with the outermost antepetalous stamen whorl developing centrifugally. Modification by reduction of the antepetalous whorl resulted in an outer alternipetalous stamen whorl in Croton section Moacroton, subgenus Quadrilobi. Several species in the subgenus Geiseleria show an independent reduction of stamen numbers by absence of a centrifugal development with the antepetalous whorl the first whorl to develop. Petal losses are observed in the distantly related C. setiger and C. dioicus. Chaotic stamen arrangement is found in C. celtidifolius (subgenus Adenophylli) as a result of a secondary stamen increase. In pistillate flowers, reduction of carpel numbers happened three times in the subgenus Geiseleria. C. monanthogynus has a bicarpellate ovary, while in C. setiger and C. michauxii the ovary is monocarpellate. Reduction of carpel number is linked with merism change and perianth reduction. The ovary in C. michauxii has basal placentation which is unique among all Croton. Moreover, strong bilateral sepals and nectaries are observed in species from section Julocroton. Therefore, the floral diversity of some species in the genus Croton could be explained by developmental modification of an ancestral form via reduction, rearrangement of stamen whorls, and symmetry shifts. [ABSTRACT FROM AUTHOR]

Senegalia was recently described as non-monophyletic; however, its sections exhibit robust monophyletic support, suggesting a potential reclassification into separate genera—Senegalia sect. Monocanthea p.p. is the largest section. It contains 164 species of pantropical distribution and includes all of the current 99 neotropical species of Senegalia; however, no morphological characteristics are available to differentiate this section. To characterize this section, we examined floral developmental traits in four species of Senegalia sect. Monocanthea p.p. These traits were previously considered as potentially distinguishing features within Acacia s.l. and include the onset patterns of the androecium, the timing of calyx union, the origin of the staminal disc, and the presence of stomata on the petals. Furthermore, we analyzed previously unexplored traits, such as corolla union types, inflorescence development, and micromorphological features related to the indumentum, as well as the presence and location of stomata. The characteristics proposed as potential synapomorphies of the group include the postgenital fusion of the corolla and the presence of a staminal disc formed at the base of the filaments. The other analyzed floral characteristics were not informative for the characterization of the group. Future studies of floral ontogeny will help to establish more precise patterns, mainly whether corolla union and staminal tube formation occur similarly in African and Asian sections of Senegalia. [ABSTRACT FROM AUTHOR]

Flower bud differentiation is the commencement of plant reproductive development. Flower organ specialization follows flower bud differentiation. This biological mechanism controls whether plants reproduce successfully via seed. Caucasian clover (Trifolium ambiguum) is used in mixed temperate pastures. However, its low natural seed setting rate contributes to a low seed yield. This study aimed to elucidate how the reproductive biology of Caucasian clover could affect seed production. Caucasian clover flower bud differentiation and flower organ development were systematically examined. Flower bud differentiation has six consecutive stages: pre‐differentiation, differentiation of the inflorescence, the floret, the perianth, the stamen, and finally the pistil primordium. The anther has two chambers. Pollen grains have six development phases: the tetraspore, early‐uninucleate, late‐uninucleate, vegetative cell and germ‐cell form, binucleate, and maturation phase. The microspore tetrad is tetrahedral, and the mature pollen grains are bicellular. Pollen grain viability was found 35%. The Caucasian clover monocarpelate ovary contains 1–2 ovules that are covered with a 2‐layer integument. The ovule is anatropous. The embryo sac development type is a polygonum. The floral formula is "⚥↑K(5) C1+1+2 A(9)+1G(1:1:1−2)". These genetic traits of two pollen sacs and low viability pollen grains may be responsible for the low natural seed setting. Poor seed setting may also be due to embryo sac dysplasia that leads to ovule sterility. Therefore, the breeding aim should be to improve pollen viability, to decrease embryo sac dysplasia and to reduce embryo abortion that could be targeted for genetic improvement to enhance seed yields. [ABSTRACT FROM AUTHOR]

The complex zygomorphic flowers of the early-diverging eudicot Delphinium provide an opportunity to explore intriguing evolutionary, developmental, and genetic questions. The dorsal perianth organs, consisting of a spurred sepal and the nectar-bearing spurred petal(s) in Delphinium, contribute to the dorsoventralization and zygomorphic flower morphology. The seamless integration of the two or three dorsal petaloid spurred organs is considered a synorganization, and the resulting organ complex is referred to as a hyperorgan. The hyperorgan shows variability within the tribe due to variation in the number, size, and shape of the spurs. Research in recent decades within this tribe has enhanced our understanding of morphological evolution of flowers. More recently, functional studies using the RNAi approach of Virus-Induced Gene Silencing (VIGS) have unraveled interesting results highlighting the role of gene duplication in the functional diversification of organ identity and symmetry genes. Research in this early-diverging eudicot genus bridges the gaps in understanding the morphological innovations that are mostly studied in model grass and core eudicot clades. This first comprehensive review synthesizes ecoevo-devo research on Delphinium, developing a holistic understanding of recent advancements and establishing the genus as an exceptional model for addressing fundamental questions in developmental genetics, particularly in the evolution of complex flowers. This progress highlights Delphinium's significant potential for future studies in this field. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Pollination is crucial to obtaining optimal blueberry yield and fruit quality. Despite substantial investments in seasonal beekeeping services, blueberry producers consistently report suboptimal pollinator visitation and fruit set in some cultivars. Flower morphology and floral rewards are among the key factors that have shown to contribute to pollinator attraction, however little is known about their relative importance for improving yield in the context of plant breeding. Clarifying the relationships between flower morphology, nectar reward content, pollinator recruitment, and pollination outcomes, as well as their genetic components, can inform breeding priorities for enhancing blueberry production. In the present study, we measured ten flower and nectar traits and indices of successful pollination, including fruit set, seed count, and fruit weight in 38 southern highbush blueberry genotypes. Additionally, we assessed pollinator visitation frequency and foraging behavior over two growing seasons. Several statistical models were tested to optimize the prediction of pollinator visitation and pollination success, including partial least squares, BayesB, ridge-regression, and random forest. Results: Random forest models obtained high predictive abilities for pollinator visitation frequency, with values of 0.54, 0.52, and 0.66 for honey bee, bumble bee, and total pollinator visits, respectively. The BayesB model provided the most consistent prediction of fruit set, fruit weight, and seed set, with predictive abilities of 0.07, -0.08, and 0.42, respectively. Variable importance analysis revealed that genotypic differences in nectar volume had the greatest impact on honey bee and bumble bee visitation, although preferences for flower morphological traits varied depending on the foraging task. Flower density was a major driving factor attracting nectar-foraging honey bees and bumble bees, while pollen-foraging bumble bees were most influenced by flower accessibility, specifically corolla length and the length-to-width ratio. Conclusions: Honey bees comprised the majority of pollinator visits, and were primarily influenced by nectar volume and flower density. Corolla length and the length-to-width ratio were also identified as the main predictors of fruit set, fruit weight, seed count, as well as pollen-foraging bumble bee visits, suggesting that these bees and their foraging preferences may play a pivotal role in fruit production. Moderate to high narrow-sense heritability values (ranging from 0.30 to 0.77) were obtained for all floral traits, indicating that selective breeding efforts may enhance cultivar attractiveness to pollinators. [ABSTRACT FROM AUTHOR]

Doping and morphology tailoring in metal sulfides up to nanoscale plays a vital role for better performance in various applications. Herein hydrothermally synthesized Co-doped nickel sulfide (NiS 2) nanostructures have been transformed from nano-rods to nano-sheets up to optimal doping concentration of 3 %. The phase changes, morphological modifications and elemental investigations have been analyzed by SEM, TEM, HRTEM, SAED, EDS, XRD and FTIR. The morphology transitions revealed that NiCo 3 S exhibited sophisticated morphology of flower like structures formed by nano-sheet patterns. NiCo 3 S electrode possesses an auspicious capacitance of 1242 Fg_1 at 1 Ag_1 within potential window range of 0.1–0.8 V. In accordance with GCD study, CV and EIS study confirmed that NiCo 3 S is more electroactive and less resistive showing excellent stability up to 92 % after 5000 cycles. The power law (b = 0.71) showed the capacitive nature of the NiCo 3 S. The capacitive and diffusive behavior calculated by Dunn's relationship confirmed the pseudocapacitive charge storage behavior of NiCo 3 S electrode making this a potential candidate for electrochemical applications. [ABSTRACT FROM AUTHOR]

Cheirostylis tortilacinia C. S. Leou (Orchidaceae), has been reported for the first time in India from Arunachal Pradesh and West Bengal. Cheirostylis tortilacinia is morphologically allied to Cheirostylis parvifolia during anthesis but clear differences can be traced on closer examination of the vegetative morphology and the floral characters. Detailed taxonomical description along with photoplates, species comparison table with the allied species from India, and notes on typification have been provided in this current communication to aid in easy identification of this species. [ABSTRACT FROM AUTHOR]

Plants flower in response to environmental signals. These signals change the shape and developmental identity of the shoot apical meristem (SAM), causing it to form flowers and inflorescences. We show that the increases in SAM width and height during floral transition correlate with changes in size of the central zone (CZ), defined by CLAVATA3 expression, and involve a transient increase in the height of the organizing center (OC), defined by WUSCHEL expression. The APETALA2 (AP2) transcription factor is required for the rapid increases in SAM height and width, by maintaining the width of the OC and increasing the height and width of the CZ. AP2 expression is repressed in the SAM at the end of floral transition, and extending the duration of its expression increases SAM width. Transcriptional repression by SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1) represents one of the mechanisms reducing AP2 expression during floral transition. Moreover, AP2 represses SOC1 transcription, and we find that reciprocal repression of SOC1 and AP2 contributes to synchronizing precise changes in meristem shape with floral transition. Bertran Garcia de Olalla, Cerise and colleagues discovered that the transcription factor APETALA2 has a dual role at the shoot tip of Arabidopsis, where it both mediates changes in the timing of flowering and in the morphology of the shoot apex. [ABSTRACT FROM AUTHOR]

Phalaenopsis is one of the most popular orchid genera, exhibiting a variety of flower morphologies. Ploidy level was a factor influencing the success of Phalaenopsis crossbreeding. This research aimed to determine the ploidy level by flow cytometry and correlation with morphological characteristics on six hybrid cultivars of Phalaenopsis (1702, 1819, 1981, 3903, 3904, and 3908). Flow cytometry analysis on young leaves and root tip cells was also carried out on P. amabilis, P. amboinensis, and P. schilleriana. Research results showed multiple peaks of fluorescence appeared on the flow cytometry histogram. The young leaves and root tip cells show the distribution of cells into different ploidy levels and indicate mixoploid and endopolyploid conditions of the cells in both leaves and root samples. This complexity makes it challenging to determine the ploidy level of each cultivar and the correlation between morphological characteristics and ploidy level, even though the weak positive correlation was prominent between flower numbers and genome size. These findings serve as foundational data on the cytogenetic background of the cultivars for orchid breeders in crossbreeding, selection of haploid plants, mutation analysis, and variety consistency monitoring. [ABSTRACT FROM AUTHOR]

The standout characteristic of the orchid perianth is the transformation of the upper median petal into a distinctively formed lip, which gives orchid flowers their typically zygomorphic symmetry and makes them the most popular ornamental plants worldwide. To study orchid flower development, two WUSCHEL -related homeobox (WOX) genes, PaWOX3 and PaWOX3B , were identified in Phalaenopsis. PaWOX3 and PaWOX3B mRNAs accumulate abundantly during early reproductive development and perianths of young buds, significantly decreasing in mature flowers and absent in vegetative leaves and roots. PaWOX3 and PaWOX3B virus-induced gene silencing (VIGS) knockdown in Phalaenopsis significantly reduces floral bud numbers, suggesting that PaWOX3/PaWOX3B may be involved in flower initiation. Transgenic Arabidopsis ectopically expressing repressor forms of PaWOX3/PaWOX3B and their Oncidium ortholog, OnPRS , exhibit lateral organ development defects, implicating these genes likely have function in regulating growth and differentiation for lateral organs. Neither PaWOX3, PaWOX3B single nor PaWOX3 / PaWOX3B double VIGS Phalaenopsis altered the flower morphology. Interestingly, double silencing of PaWOX3 or PaWOX3B with OAGL6-2 , which controlled the identity/formation of lips, altered the symmetry of 'BigLip' produced in OAGL6-2 VIGS. This result indicated that the levels of PaWOX3 / PaWOX3B are still sufficient to maintain the symmetry for the OAGL6-2 VIGS 'BigLip'. However, the symmetry of the OAGL6-2 VIGS 'BigLip' cannot be maintained once the expression of PaWOX3 or PaWOX3B is further reduced. Thus, in addition to controlling lip identity, this study further found that OAGL6-2 could cooperate with functionally redundant PaWOX3 / PaWOX3B in maintaining the symmetric axis of lip. [ABSTRACT FROM AUTHOR]

This study employed scanning electron microscopy to investigate the pollen morphology of Taiwanese Asparagaceae species, revealing that their pollen morphology closely aligns with that of other monocotyledonous plant taxa such as Asparagales, Commelinales, and Bromeliales. Despite the overall similarity, variations in pollen morphology across different genera were noted, highlighting its potential utility in classification. Unlike the wide diversity observed in flower morphology, Asparagaceae pollen morphology appears conservative, rendering it less effective as a taxonomic marker at the species level. The study also delved into the effects of pollenkitt and harmomegathy on pollen morphology, discovering that pollenkitt partially or completely coats the pollen surface, potentially complicating the identification of exine sculpture. Furthermore, the harmomegathic effect was observed to influence aperture dynamics. Consequently, observing both hydrated and dried pollen is advisable, as it can more accurately depict the pollen's aperture morphology and offer additional insights for pollen grain analysis. [ABSTRACT FROM AUTHOR]

• Pollination is essential for both fruit production as well as genetic variations. • Dichogamous nature of walnut is hindering pollination, fruit set and breeding. • Inter-specific hybrids offer considerable variations and genetic diversity. • Better understanding of pollination mechanisms can reduce PFA in walnuts. Pollination promotes both fruit production as well as genetic variations in fruit crops. Walnut belongs to the deciduous, monoecious, anemophilous and self-compatible fruit tree. Regardless of self-compatibility, due to dichogamous nature of crop it is hindering pollination, fruit set and breeding in walnut. Pollination mechanisms in walnut are not completely understood, and this unusually complex pollination behavior necessitates that we improve our mechanistic understanding of cytology, flower and pollen morphology, pollen collection, storage and germination and pollination process in walnut. A deeper understanding of pollination mechanisms is vital for fruit production as well as to reduce pistillate flower abortion (PFA) and to speed up future walnut breeding and varietal improvement by enhancing genetic diversity and developing hybrid verities targeted for having desirable traits like lateral bearing, precocity, batter fruit quality, high productivity, earlier harvest and resistance to late-spring frost, cherry leaf roll virus (CLRV), blight and pistillate flower abortion. A comprehensive grasp of walnut pollination mechanisms enables experts to offer more effective technical guidance to walnut growers. This article presents recent advancements in our understanding, consolidating pertinent and up-to-date information on walnut pollination mechanisms into a single resource for the first time. It serves as a valuable reference for researchers engaged in horticultural research, particularly in the domains of pollination, fruit production, and walnut tree breeding. [ABSTRACT FROM AUTHOR]

Speciation is a complex process typically accompanied by significant genetic and morphological differences between sister populations. In plants, divergent floral morphologies and pollinator differences can result in reproductive isolation between populations. Here, we explore floral trait differences between two recently diverged species, Gilia yorkii and G. capitata. The distributions of floral traits in parental, F1, and F2 populations are compared, and groups of correlated traits are identified. We describe the genetic architecture of floral traits through a quantitative trait locus analysis using an F2 population of 187 individuals. While all identified quantitative trait locus were of moderate (10–25%) effect, interestingly, most quantitative trait locus intervals were non-overlapping, suggesting that, in general, traits do not share a common genetic basis. Our results provide a framework for future identification of genes involved in the evolution of floral morphology. [ABSTRACT FROM AUTHOR]

Cymbidium faberi Rolfe is one of the traditional Chinese orchids with important ornamental value, and the cultivation of Cymbidium faberi Rolfe mutant strains with different appearances is essential to increase its economic value. However, at present, their acquisition largely relies on natural mutation. The objectives of this research were to mutagenize Cymbidium faberi Rolfe protocorm-like bodies (PLBs) and shoots in vitro using sodium azide (NaN3) and to screen and evaluate mutants in the mutagenized seedlings using morphological characteristics. Cymbidium faberi Rolfe PLBs and shoots were used as mutagenic materials. Mutations were induced by the addition of 0.0 (control), 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 mg·L−1 and 0.0 (control), 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, and 10.0 mg·L−1 NaN3 to a shoot-growth-inducing medium. The mortality rates of the PLBs and shoots increased with an increase in the NaN3 concentration. At 14 d of co-cultivation, the PLBs and shoots were most efficiently mutagenized with 1.5 mg·L−1 and 4.0 mg·L−1 NaN3, respectively. After the explants were cultured for 3 months, changes in leaf and flower morphology were observed in some mutants: shorter and thicker leaves, shorter node length, reduced height, and mid-translucent leaves compared with controls. Some Cymbidium faberi Rolfe bloomed prematurely, with single flowers with large, thick petal sepals and small inflorescences. Colors included light green throughout, with some exhibiting purple stamens. This suggests that NaN3 can effectively mutagenize Cymbidium faberi Rolfe PLBs and shoots to satisfy people's demand for this plant's ornamental properties while increasing its economic value. [ABSTRACT FROM AUTHOR]

Pollinator choices when selecting flowers for nectar or pollen collection are crucial in determining the effectiveness of pollination services provided to plants. From the plant's perspective, this effectiveness is a phenomenon shaped by factors at both the species‐ (e.g. pollinator density and flower morphology) and community‐level, including pollinator diversity and plant competition for pollinators. At the species level, individual pollinator effectiveness is influenced by foraging choices, plant identity, and the resulting pollen flow within and between plant species. In natural ecosystems, these species coexist within a complex community, where various interactions can modify foraging choices and alter pollen flows, giving rise to community‐level effectiveness, a less explored aspect of pollinator effectiveness. This study investigates the drivers of individual pollinator foraging choices across two study areas and two flowering seasons. It also assesses the community‐level effectiveness of pollination services received by different plant species, considering indirect interactions between plants through shared pollinators and evaluating their impact on plant reproductive success. Our results show that the determinants of pollinator foraging choices are consistent across different habitats, with floral constancy and flower abundance playing pivotal roles across all species and sites. Foraging choices can shift throughout the flowering season as plant and pollinator composition changes, significantly impacting pollination effectiveness. The overlap in pollination service use by individuals of the same plant species decreases their fruit set, whereas sharing pollinator services with individuals of other plant species increases fruit set. Our results support significant, positive biodiversity–ecosystem functioning associations driven by both plant and pollinator species richness, suggesting that the overlap in pollination service use by different plant species fosters facilitative interactions rather than competition. This is likely influenced by more stable pollination supplies under high plant species diversity conditions and the existence of mechanisms to mitigate the negative impacts of heterospecific pollen deposition. [ABSTRACT FROM AUTHOR]

Summary: Plants can evolve rapidly after pollinator changes, but the response of different floral traits to novel selection can vary. Floral morphology is often expected to show high integration to maintain pollination accuracy, while nectar traits can be more environmentally sensitive. The relative role of genetic correlations and phenotypic plasticity (PP) in floral evolution remains unclear, particularly for nectar traits, and can be studied in the context of recent pollinator changes.Digitalis purpurea shows rapid recent evolution of corolla morphology but not nectar traits following a range expansion with hummingbirds added as pollinators. We use this species to compare PP, heritability, evolvability and integration of floral morphology and nectar in a common garden.Morphological traits showed higher heritability than nectar traits, and the proximal section of the corolla, which regulates access to nectar and underwent rapid change in introduced populations, presented lower integration than the rest of the floral phenotype. Nectar was more plastic than morphology, driven by highly plastic sugar concentration. Nectar production rate showed high potential to respond to selection.These results explain the differential rapid evolution of floral traits previously observed in this species and show how intrafloral modularity determines variable evolutionary potential in morphological and nectar traits. [ABSTRACT FROM AUTHOR]

Prosthechea karwinskii is an orchid endemic to Mexico, threatened by the destruction of its habitat and the extraction of specimens to meet its demand for ornamental and religious use. Most of its populations, including the most locally abundant ones, are found in Oaxaca state. Variations in some floral traits have been observed in these populations. We implemented a morphometric analysis to assess their floral variation and identify the most significant characters in the morphological patterns of this orchid. Floral samples were collected from 17 populations of P. karwinskii in Oaxaca, as well as from specimens used as ornaments during Easter in an Oaxacan community (Zaachila), whose origin is unknown. Sampling of natural populations covered the environmental, geographic, and morphological variation of the species. We performed an analysis of variance (ANOVA), principal component analysis (PCA), canonical variate analysis (CVA), and cluster analysis, including 185 individuals and 45 variables (12 of them were discarded in the multivariate analyses due to high correlation). Characters of the column, lateral sepal, and labellum were most informative for the observed morphological patterns. Albarradas showed the greatest morphological differentiation, mainly due to the column. In general, individuals from the same locality tended to overlap more, especially the populations of Jaltianguis and Yahuiche, which were different from the geographically close population of Etla. Teposcolula presented the highest values in perianth characters, unlike Sola_Rancho Viejo. The specimens recovered from religious ornaments were morphologically more similar to those from Yanhuitlan and Etla. This morphometric analysis identified characters as potential taxonomic markers for P. karwinskii and related species, showing its potential to associate specimens of unknown origin with their probable geographical region. Our work encourages working on collaborative conservation strategies to ensure the long-term permanence of both the species and its traditional uses. [ABSTRACT FROM AUTHOR]

Heliconia (Heliconiaceae) is a genus of giant rhizomatous herbs that have bright and striking bract inflorescences. The family consists of one genus and about 194 species that occur naturally in the tropical regions of the world, concentrating their greatest diversity and endemism in the Andean foothills and the Pacific region of Colombia, with approximately 120 species of the total registered for the world. Within the species of this genus there is high morphological variation, which sometimes makes clear identification of Heliconia specimens difficult. So is the case of Heliconia platystachys Baker, which contains two morphologically distinct groups of plants distinguished by the size and color of the bracts, the floral bracts, the mucilage that covers the flowers, and the shape of the staminodium. These structures of floral biology such as staminodium are of great taxonomic value in the study of the species within the genus Heliconia. The main goal of this work was to study Heliconia populations, which are found on the western slope of the Central Cordillera of Colombia at elevations between 970 and 1200 m, for which the morphoanatomical and palynological attributes were analyzed. We want to explore in this work whether the variation exhibited by these populations and their distribution allows us to postulate the occurrence of a new species with sufficient evidence for its separation. [ABSTRACT FROM AUTHOR]

Gastrodia daweishanensis Ying Qin & Yan Liu (Orchidaceae), a new species from Yunnan, China is described. The new species is similar to G. putaoensis X. H. Jin, but differs from the latter by its yellow flowers, perianth tube ventrally distinctly swollen near the base forming a pouch-shaped outgrowth and inner surface of the front half densely pubescent. The detailed information of the new species, including morphological descriptions, illustrations, phenology, etymology and conservation assessment are provided. [ABSTRACT FROM AUTHOR]

We analyzed the floral morphology and nectar production of several cultivars and species of Monarda representing five cultivars and four species grown in Georgia Piedmont and Montane regions. Over the course of two seasons, we detected significant differences among the samples in terms of inflorescence size, petal lobe and corolla widths and lengths, and total sugar content. M. didyma had larger glomerules, longer corollas and petal lobes, and higher nectar volume and total sugar content per flower. M. fistulosa and M. punctata had smaller glomerules, corolla and petal lobe lengths, and total sugar content per flower. Petal lobe and corolla length strongly correlated with sucrose and nectar production. Combined with data on horticultural performance, these results could be valuable in informing breeding goals for conservation-oriented landscape plants. [ABSTRACT FROM AUTHOR]

Camellia chekiangoleosa has high oil concentration and oleic acid content, while C. semiserrata has strong growth vigor and resistance. In order to make the utmost of the advantages of C. chekiangoleosa and C. semiserrata and cultivate excellent germplasm materials, the phenotypic traits of 45 F1 hybrid progenies of C. chekiangoleosa and C. semiserrata were analyzed to grasp the phenotypic traits of the hybrid progenies. In addition, SSR markers were used to identify hybrids, and SSR markers that could be used to identify the hybrid progenies of oil tea were screened. The results were as follows: (1)The F1 hybrids of C. chekiangoleosa × C. semiserrata showed tall tree and rapid growth, and their leaf veins, sepals and stigmas were all tended to the traits of the male parent C. semiserrata, while flower and leaf morphologies and other traits were similar to the female parent C. chekiangoleosa, and the characteristics of leaf color and size were between those of the parents. (2)From the 32 SSR markers, eight fully complementary markers that could distinguish parents and determine the origin of offspring were screened out for identification of hybrid progenies, among which the hybrid identification rates of seven markers were as high as 100%, and the hybrid identification rate of one marker was 55. 56%. And 45 hybrid progenies were all true hybrids identified by the complementarity of eight markers. (3)The eight SSR markers were used to verify the ability to identify the hybrid progenies, indicating that it is feasible to use these SSR markers to identify the authenticity of the hybrid progenies of oil tea. This study results provide a reference for interspecies cross breeding of oil tea, and also provide a reference for the SSR marker identification of hybrids of oil tea. [ABSTRACT FROM AUTHOR]

Fossil leaves, fruits, and woods assigned to Rhamnaceae have been recorded from India, however, there are no previous reports of rhamnaceous fossil flowers from India. Here, we report the first fossil flowers in appreciable numbers from the early Eocene (Palana Formation) sedimentary sequences of Gurha Lignite Mine, Rajasthan, western India, and show that they are attributable to Rhamnaceae. We examined variation in flower morphology among extant and extinct rhamnaceous species as a basis for interpreting our fossil flowers. The specimens are small star‐like, pentamerous, actinomorphic, gamosepalous flowers with triangular, keeled sepals with acute apices, spathulate, short‐clawed petals alternating with sepals, shallow, five‐lobed nectary disc with prominent pentagonal outer margin, and a centrally placed globose ovary with stigma scar. The flowers co‐occur with ziziphoid leaves and are recognized as a new species Eopaliura indica Patel, Rana & Khan sp. nov. Because of aforesaid characteristics, fossil flowers are easily identifiable as Rhamnaceae and should provide a reliable means of documenting the evolutionary history of this family during the Cenozoic. [ABSTRACT FROM AUTHOR]

The development of floral organs, crucial for the establishment of floral symmetry and morphology in higher plants, is regulated by MADS-box genes. In sunflower, the capitulum is comprised of ray and disc florets with various floral organs. In the sunflower long petal mutant (lpm), the abnormal disc (ray-like) floret possesses prolongated petals and degenerated stamens, resulting in a transformation from zygomorphic to actinomorphic symmetry. In this study, we investigated the effect of MADS-box genes on floral organs, particularly on petals, using WT and lpm plants as materials. Based on our RNA-seq data, 29 MADS-box candidate genes were identified, and their roles on floral organ development, especially in petals, were explored, by analyzing the expression levels in various tissues in WT and lpm plants through RNA-sequencing and qPCR. The results suggested that HaMADS3, HaMADS7, and HaMADS8 could regulate petal development in sunflower. High levels of HaMADS3 that relieved the inhibition of cell proliferation, together with low levels of HaMADS7 and HaMADS8, promoted petal prolongation and maintained the morphology of ray florets. In contrast, low levels of HaMADS3 and high levels of HaMADS7 and HaMADS8 repressed petal extension and maintained the morphology of disc florets. Their coordination may contribute to the differentiation of disc and ray florets in sunflower and maintain the balance between attracting pollinators and producing offspring. Meanwhile, Pearson correlation analysis between petal length and expression levels of MADS-box genes further indicated their involvement in petal prolongation. Additionally, the analysis of cis-acting elements indicated that these three MADS-box genes may regulate petal development and floral symmetry establishment by regulating the expression activity of HaCYC2c. Our findings can provide some new understanding of the molecular regulatory network of petal development and floral morphology formation, as well as the differentiation of disc and ray florets in sunflower. [ABSTRACT FROM AUTHOR]

(1) Background: Tree peonies display extensive cultivar diversity due to widespread hybridization, resulting in a complex genetic architecture. This complexity complicates the selection of universal reference genes across different cultivars for qRT-PCR analyses. Paeonia suffruticosa 'Doulv', notable for its unique green blooms in China, exhibits chlorosis post-flowering and features petaloid stamens and pistils. (2) Methods: Based on published literature and RNA-seq data from 'Doulv', nine candidate reference genes—ACT (Actin), TUB (β-Tubulin), UBC (Ubiquitin Conjugating Enzyme), UBQ (Ubiquitin), UPL (Ubiquitin Protein Ligase), PP2A (Protein Phosphatase 2A), PP2C (Protein Phosphatase 2C), MBF1A (Multiprotein Bridging Factor 1A), and GAPDH (Glyceraldehyde-3-Phosphate Dehydrogenase)—were selected. Their expression stability was assessed across various tissues and developmental stages of 'Doulv' flowers using qRT-PCR, with evaluations conducted via GeNorm_v3.5, NormFinder_v20, and BestKeeper_v1.0. Gene cloning and expression analyses of PsCUC3, including its subcellular localization, were performed. (3) Results: GAPDH and ACT were identified as the most stable reference genes in petaloid stamens across various developmental stages of 'Doulv', whereas UBC and MBF1A were optimal across different tissues. Notably, specific conserved amino acids in PsCUC3 from 'Doulv' diverged from those in NAM/CUC3 proteins of other species, impacting its protein structure. PsCUC3 expression analysis revealed no correlation with chlorophyll content in petaloid stamens but an association with petaloid organ development. Furthermore, PsCUC3 was predominantly localized in the nucleus. (4) Conclusions: This study comprehensively evaluated suitable reference genes using GeNorm_v3.5, NormFinder_v20, and BestKeeper_v1.0 software, establishing a robust qRT-PCR detection system for 'Doulv' peony. These results provide a solid experimental foundation for further research on 'Doulv' peony. Building on this experimental foundation, the functional analysis of the PsCUC3 gene was conducted. The findings suggest a potential association between the PsCUC3 gene and floral morphology alterations in 'Doulv', identifying PsCUC3 as crucial for understanding the molecular mechanisms influencing floral structure in tree peonies. [ABSTRACT FROM AUTHOR]

Reproductive development of rice (Oryza sativa L.) is critical for obtaining high yield by promoting fertilization at the flowering stage. However, limited information is available about historical changes in anther and stigma morphology during breeding programs; these characteristics contribute strongly to a cultivar's abiotic stress resistance. We tested the hypothesis that genetic progress for culm length during breeding has affected the floral morphology of rice cultivars released in Japan. We used field trials in 2 years in northern Japan to quantify anther and stigma morphology and culm length for rice from 147 cultivars (2020) and 284 cultivars (2021) that had been released from 1902 to 2011 (109 years) in Japan under two nitrogen (N) regimes (no‐N and high‐N). Culm length significantly decreased over time at a rate of 1.9–3.1 cm per 10 years at low N. However, anther length, anther width, and stigma length showed no consistent trend during the period. High N significantly increased culm length of most cultivars by an average of 21%–26% but tended to shorten anther length by 2%–3% and anther width by 1%–2% on average and increased stigma length by only 1%, with large variation among cultivars. Our results suggested no evidence on positive breeding efforts targeting on floral morphology to improve abiotic stress tolerance and yield in contract with culm length. Core Ideas: Reproductive development of rice is critical for obtaining high yield by promoting fertilization.However, limited information is available about historical changes in anther and stigma morphology during breeding.We evaluated changes in anther and stigma morphology of 284 Japanese rice cultivars since 1902.Culm length has decreased since 1902; anther length and width and stigma length showed no trend.High nitrogen (N) increased most cultivars' culm length, but not anther length and width and stigma length. [ABSTRACT FROM AUTHOR]