Corydalis nanchuanensis (Papaveraceae), a new species from Chongqing, China

Corydalis nanchuanensis (Papaveraceae), a new species from Nanchuan district in south-west Chongqing, China, is described and illustrated. Morphologically, the new species is similar to C. sheareri, a species mainly distributed in south China and Vietnam, in having conical corolla spurs, divided lower bracts, rounded stigmas, larger elaiosomes (usually longer than seeds), and tubers, but differs by having tapering-to-base (vs. uniformly sized) stems; entire (vs. usually crenate) leaf lobes, straight (vs. declined) pedicels in fruit, concave (vs. subacute) apices of outer petals, white (vs. usually purple) abaxial side of inner petals, and reticulate (vs. tuberculate) seeds.

Correlating Structure and Morphology of Andiroba Leaf (Carapa guianensis Aubl.) by Microscopy and Fractal Theory Analyses

The Amazon rainforest is considered a megadiverse biome, where several species of its rich flora are still unknown. The anatomy of their leaves usually identifies species. In this paper, we present a complete characterization of the leaf surface of Amazon Carapa guianensis Aubl. (Andiroba), using microscopy and fractal theory to be considered a possible tool for investigating different leaves spatial patterns, especially in species with similar leaf architecture. The SEM results revealed the cellular structures and other non-cellular structures that make up the leaf architecture, both for the abaxial and adaxial sides. The cells responsible for the plant photosynthesis process were observed in the internal structure of the leaf. The wettability analysis showed that the abaxial side is more hydrophobic, while the adaxial side is more hydrophilic. AFM images exposed the relevant details of the microstructure of the leaf abaxial side, such as stomata, pores, furrows, contour, particles, and rough profiles generated by topographic irregularities. The statistical parameters revealed that the scale size influences the topographic roughness, surface asymmetry, and shape of the height distribution, also observed by advanced parameters obtained according to the standard of the international organization for standardization (ISO). The fractal and advanced fractal parameters confirmed changes in spatial patterns as a function of scale size. The largest area exhibited greater spatial complexity, low dominant spatial frequencies, more excellent surface percolation, intermediate topographic homogeneity, and high uniformity of spatial patterns.

Adaptation and taxonomic value of leaf anatomical characteristics of selected Ipomoea L. species

Aim: To investigate the taxonomic value of leaf anatomical characteristics and to determine the anatomical features that enabled the species to adapt to different environmental conditions. Methodology: Three methods were applied for leaf anatomy observation: sectioning using a sliding microtome, leaf clearing and epidermal peels. Results: The findings showed some common anatomical characteristics shared in all species studied, such as incomplete leaf venation, the presence of trichome and schlerenchyma cells, and the presence of mucilaginous idioblast cells in the petiole and midrib. Straight-to-sinuous anticlinal cell walls, amphistomatic leaves, and three types of stomata: parasitic, anomocytic and staurocytic were on the abaxial side of leaf lamina in this study. Peltate and capitate glandular trichome, as well as simple trichome, were all present in the petiole, midrib and lamina. However, peltate glandular trichome were only found in the root of I. triloba. Druses were observed in all species, except I. batatas. Interpretation: Leaf anatomical characteristics possess taxonomic value, especially in species differentiation and identification, that can be subsequently useful in explaining plant's adaptation to their environment.

Strengthening Structures in the Petiole–Lamina Junction of Peltate Leaves

Peltate- or umbrella- shaped leaves are characterised by a petiole more or less centrally attached to the lamina on the abaxial side. The transition from the petiole to lamina in peltate leaves resembles a significant and abrupt geometrical change from a beam to a plate in a very compact shape. Since these leaves have not been subject of many studies, the distribution of that specific leaf morphology in the plant kingdom was investigated. Furthermore, the connection between the petiole and lamina of several peltate species was studied anatomically and morphologically, focusing on the reinforcing fibre strands. We found peltate leaves in 357 species representing 25 orders, 40 families and 99 genera. The majority are herbaceous perennials growing in shady, humid to wet habitats mainly distributed in the subtropical–tropical zones. Detailed anatomical investigation of 41 species revealed several distinct principles of how the transition zone between the petiole and lamina is organised. In-depth analysis of these different types accompanied by finite element-modelling could serve as inspiration for supporting structures in lightweight construction.

Leaf Anatomy and Micromorphology Characteristics of Ketum [Mitragyna speciosa (Korth.) Havil.] (Rubiaceae)

Mitragyna speciosa (Korth.) Havil. or locally known as ketum/daun sebiak/biakbiak belongs to Rubiaceae family and generally occurs in secondary forest or disturbed areas in tropical and subtropical region. This research enumerated the characterisation of Mitragyna speciosa leaf anatomy and micromorphology features which is still not well documented. This medium to large sized tree species characterised with opposite arrangement, ovate-acuminate leaf and with 12–17 pairs of veins. Transverse sections of petioles showed that this species has petiole outlines with slightly convex at the middle of the adaxial part and ‘U’-shaped on abaxial side. Results also showed that this species has paracytic and hypostomatic stomata, combination of non-glandular (majority) and glandular trichomes (minority), with observation on the secretory cells present in petiole and midrib parenchyma cells. Cuticle on the abaxial and adaxial epidermal surfaces showed the presence granule and wax films with periclinal and anticlinal walls can be differentiated clearly. The results obtained in this study can be used to providing additional systematics information of Mitragyna speciosa with the documentation of the leaf anatomy and micromorphology characters.

Transcriptional Dynamics of Genes Purportedly Involved in the Control of Meiosis, Carbohydrate, and Secondary Metabolism during Sporulation in Ganoderma lucidum

Ganoderma lucidum spores (GLS), the mature germ cells ejected from the abaxial side of the pileus, have diverse pharmacological effects. However, the genetic regulation of sporulation in this fungus remains unknown. Here, samples corresponding to the abaxial side of the pileus were collected from strain YW-1 at three sequential developmental stages and were then subjected to a transcriptome assay. We identified 1598 differentially expressed genes (DEGs) and found that the genes related to carbohydrate metabolism were strongly expressed during spore morphogenesis. In particular, genes involved in trehalose and malate synthesis were upregulated, implying the accumulation of specific carbohydrates in mature G. lucidum spores. Furthermore, the expression of genes involved in triterpenoid and ergosterol biosynthesis was high in the young fruiting body but gradually decreased with sporulation. Finally, spore development-related regulatory pathways were explored by analyzing the DNA binding motifs of 24 transcription factors that are considered to participate in the control of sporulation. Our results provide a dataset of dynamic gene expression during sporulation in G. lucidum. They also shed light on genes potentially involved in transcriptional regulation of the meiotic process, metabolism pathways in energy provision, and ganoderic acids and ergosterol biosynthesis.

Chrysosplenium fallax (Saxifragaceae), a new species from the Russian Far East

A new species of Chrysosplenium (Saxifragaceae), C. fallax (ser. Pilosa), is described and illustrated from Primorsky Krai, the Far East of Russia. Chrysosplenium fallax forms specialized underground stolons during budding and early flowering. The largest leaves are located at the top of vegetative shoot and have a cuneate base and pubescence on the abaxial side. The top of vegetative shoot does not take roots. The distinguishing morphological features and the differences in the seasonal development of C. fallax from the closely related C. pilosum and C. villosum (ser. Pilosa) are listed.

Effect of Drought on Trichome Density and Length in Cotton (Gossypium Hirsutum)

Cotton is a major cash crop and backbone of the textile industry in Pakistan which is badly affected by sucking insects. Drought is an important abiotic factor in trichome development. The objective of the study was to determine the effects of drought on trichome density and length. Trichome density was measured in two ways, one through the scaling method and the other through counting the trichome density manually. The scaling method is qualitative grading while quantitative grading includes trichomecount in a card of optimized length. Three scales were finalized to classify leaves on the basis of trichomes which were counted in a specific area (0.25cm2) on abaxial side of the leaf. In drought stress, trichomes density and length were measured and compared to that in normal conditions. Trichome density varies from 12 to 56 in 0.25cm2 under drought stress. On the basis of correlation of trichome density with stomatal conductance, photosynthetic rate, PAR and transpiration ratio under drought and normal conditions, it was concluded that trichome density increased as a result of drought stress.

A Role for Auxin in Triggering Lamina Outgrowth of Unifacial Leaves

A common morphological feature of typical angiosperms is the patterning of lateral organs along primary axes of asymmetry—a proximodistal, a mediolateral, and an adaxial–abaxial axis. Angiosperm leaves usually have distinct adaxial–abaxial identity, which is required for the development of a flat shape. By contrast, many unifacial leaves, consisting of only the abaxial side, show a flattened morphology. This implicates a unique mechanism that allows leaf flattening independent of adaxial–abaxial identity. In this study, we report a role for auxin in outgrowth of unifacial leaves. In two closely related unifacial-leaved species of Juncaceae, Juncus prismatocarpus with flattened leaves, and J. wallichianus with transversally radialized leaves, the auxin-responsive gene GLYCOSIDE HYDROLASE3 (GH3) displayed spatially different expression patterns within leaf primordia. Treatment of J. prismatocarpus seedlings with exogenous auxin or auxin transport inhibitors, which disturb endogenous auxin distribution, eliminated leaf flatness, resulting in a transversally radialized morphology. These treatments did not affect the radialized morphology of leaves of J. wallichianus. Moreover, elimination of leaf flatness by these treatments accompanied dysregulated expression of genetic factors needed to specify the leaf central-marginal polarity in J. prismatocarpus. The findings imply that lamina outgrowth of unifacial leaves relies on proper placement of auxin, which might induce initial leaf flattening and subsequently act to specify leaf polarity, promoting further flattening growth of leaves.

A molecular approach reveals Tranzschelia discolor as the causal agent of rust on plum and peach in Brazil

Plum and peach are important crops in the southernmost regions of Brazil and in the majority, fresh fruit producers are small producers, which guarantee their family income. Tranzschelia discolor and T. pruni-spinosae are the etiological agents of rust on Prunus domestica (plum) and P. persica (peach) in Brazil (Mendes and Urben, 2020). The molecular characterization of Tranzschelia specimens revealed different clades that are not attributed to known species, showing the need for taxonomic evaluation of Tranzschelia species in the tropics (Scholler et al. 2014; 2019). As Tranzschelia species reported in Brazil were identified only by morphological characteristics, this study aimed to carry out a survey to verify the etiology of rust on plum and peach based on molecular data. In 2018, rust symptoms in peach and plum trees were observed with maximum severity of 30% and 35%, respectively, in three Brazilian states. Symptoms of plum and peach rust are yellowish-green spots visible on the adaxial side of the leaves and uredia/uredinial sori releasing the brown urediniospores on the abaxial side (Supplementary figure 1). Symptomatic leaves of plum and peach were collected at Curitiba in the states of Paraná (lat. 25°25’47” S and long. 49°16’19” W, altitude of 935 meters) in a research station, Videira in Santa Catarina (lat. 27°00’30” S and long. 51°09’06” W, altitude of 750 meters) in a research station and Paranapanema in São Paulo (lat. 23º23'19" S and long. 48º43'22" W, altitude of 610 meters) in a farmer field, and deposited in the herbarium of the Municipal Botanical Museum of Curitiba (MBM 429790 to 429795). Urediniospores collected on plum and peach leaves were all echinulate, obovoid, orange-brown, and measured 18.0 – 33.5 μm × 10.5 – 20.5 μm (n=150) and 22.5 – 40.0 μm × 11.5 – 20.5 μm (n=150), respectively. The genomic DNA of the urediniospores was extracted for amplification and sequencing of the internal transcribed spacer region (ITS) using primers ITS5-u and ITS4-u (Pfunder et al. 2001). The sequences were deposited (Accession Nos. MT786213 to MT786218) and compared to sequences in the GenBank repository using the BLASTn algorithm. The sequences of ITS showed a high percentage of identity (>99%) with sequences from T. discolor (Accession Nos. AB097449, EU014071, KU712078, KY764179, MH599069, MN545867, DQ995341, DQ354542, and KX985768). Additionally, our isolates clustered with others T. discolor in a Bayesian phylogenetic tree based on ITS sequences (study S26663 deposited in TreeBASE) (Supplementary figure 2). A pathogenicity test was carried out on plants by inoculation of a 1.5 × 105 urediniospores mL-1 suspension on the abaxial side of the leaves. Leaves sprayed with sterile water were used as controls. The plants were incubated in a growth chamber (GC) in the dark for 48 h at 23 °C and maintained with 100% RH to establish infections. The inoculated plants were afterwards kept in the GC at a photoperiod of 12 h under same conditions until 14 days when the symptoms and pathogen structures were observed to all six isolates. Control leaves remained symptomless. Tranzschelia discolor infect plants in the genus Prunus, including almond, apricot, nectarine, cherry, peach, and plum (Farr and Rossman 2021). As T. pruni-spinosae was not found, T. discolor is probably the prevalent species in the main regions of Brazil. This information reveals T. discolor as the causal agent of plum and peach rust in Brazil and helps to understand the distribution of this disease in tropics or worldwide.