Leaf Margin Serration Research Articles

Salvia tainingensis, a neglected new species of Lamiaceae from Fujian Province, China

A species could not be known to the world of science if it not be discovered and described, considerable number of new species are neglected due to the plant itself and some other external restricted factors. On the basis of morphological and molecular evidences, a new species previously identified as Salvia scapiformis is now described and illustrated as Salvia tainingensis, named after Taining County in Fujian Province, where it was discovered. S. tainingensis does not closely resemble S. scapiformis, but is more similar to Salvia glabrifolia and Salvia daiguii, which were once identified as S. scapiformis, in terms of leaf shape, apex, base, corolla color, and connective length. However, it can be easily distinguished from the latter two by its thinly leathery leaves, serrate leaf margins, densely villous or glabrescent leaf abaxial, and the X-shaped arrangement of connective and filament.

Pouzolzia friisii (Urticaceae, Boehmerieae), a new species from north‐east India

Based on a collection housed at LWG (Herbarium of CSIR–National Botanical Research Institute, Lucknow, India), collected by Singh et al. on 25 June 2017 from Nagaland state of India, Pouzolzia friisii A.Gupta & V.Wagh sp. nov. (Urticaceae) is described and illustrated. The species resembles Pouzolzia sanguinea var. fulgens, P. niveotomentossa and P. australis in its serrated leaf margins and the indumentum on the abaxial leaf surface however, P. friisii is quite distinct in its grayish or pale yellowish indumentum, 4‐merous sessile male flowers and densely pubescent fruiting perianths without wings and ribs. A detailed description, illustration, distribution map, and information on ecology, as well as phenology are presented.

New species of Salicaceae with opposite leaves from the Atlantic Forest, Brazil

Abatia mantiqueirensis is described and illustrated as a new species with distribution for the Brazilian states of Minas Gerais and Rio de Janeiro. It is morphologically similar to A. americana but can be distinguished by the presence of canaliculated petiole, acute serrate leaf margin, glands at the apex of the margin serrations that are rounded to concave and projected outwards from the leaf blade, upper portion of the pedicel winged and seeds with tiny dorsal wings. Taxonomic description, comments, and geographical distribution information are here in provided. So far, only three populations of A. mantiqueirensis are known with only one of them recorded in a protected area. Based on the availability of suitable habitats, possible threats and future potential geographical distribution, we propose the conservation status for A. mantiqueirensis as Critically Endangered.

Characterization and evaluation of the morphological attributes of Ethiopian mustard (Brassica carinata A. Braun) landraces

Ethiopian mustard (Brassica carinata A. Braun) is one of the Brassica leafy vegetables and oilseed crops, which can withstand adverse environmental conditions. This study was conducted to characterize and evaluate the leaf attributes of 313 Ethiopian mustard accessions grown in the greenhouse and field in 2018/19 in Beijing, China. Data on 18 different leaf morphological attributes were collected based on the IBPGR for Brassica and Raphanus descriptor format and Fiji Image J. The collected data were subjected to descriptive statistics using JMP version 14 software. Results indicate that the majority of the accessions had serrated leaf margin, intermediate juvenile development, rounded apex leaf shape, absence of leaf pubescence, number of lobes > 5 and had intermediate number of leaves per plant with frequencies of 101, 213, 223, 244, 183 and 289, respectively. The accessions had also white midrib color, light green leaf color, purple petiole color, purple stem color and purple apex leaf color pigments with frequencies of 168, 165, 104, 113 and 122, respectively. Significant differences were observed among the accessions for leaf size attributes (p < 0.001) indicating their potential as leafy vegetables. Furthermore, there were significant accession × environment effects for the laminal length, total leaf length, leaf area, leaf weight and petiole length. Notably, 71% of the accessions had an average of 81 days flowering time. The multivariate cluster and principal component analyses divided the 313 accessions into eight groups with distinctive information; consisting of 81, 37, 79, 38, 14, 11, 6 and 47 accessions. Thus, this study provides important information about Ethiopian mustard germplasms that is vital for further advancement and genetic improvement of the crop.

Leaf dissection and margin serration are independently regulated by two regulators converging on the CUC2-auxin module in strawberry.

The remarkable diversity of leaf forms allows plants to adapt to their living environment. In general, leaf diversity is shaped by leaf complexity (compound or simple) and leaf margin pattern (entire, serrated, or lobed). Prior studies in multiple species have uncovered a conserved module of CUC2-auxin that regulates both leaf complexity and margin serration. How this module is regulated in different species to contribute to the species-specific leaf form is unclear. Furthermore, the mechanistic connection between leaf complexity and leaf serration regulation is not well studied. Strawberry has trifoliate compound leaves with serrations at the margin. In the wild strawberry Fragaria vesca, a mutant named salad was isolated that showed deeper leaf serrations but normal leaf complexity. SALAD encodes a single-Myb domain protein and is expressed at the leaf margin. Genetic analysis showed that cuc2a is epistatic to salad, indicating that SALAD normally limits leaf serration depth by repressing CUC2a expression. When both Arabidopsis homologs of SALAD were knocked out, deeper serrations were observed in Arabidopsis rosette leaves, supporting a conserved function of SALAD in leaf serration regulation. We incorporated the analysis of a third strawberry mutant simple leaf 1 (sl1) with reduced leaf complexity but normal leaf serration. We showed that SL1 and SALAD independently regulate CUC2a at different stages of leaf development to, respectively, regulate leaf complexity and leaf serration. Our results provide a clear and simple mechanism of how leaf complexity and leaf serration are coordinately as well as independently regulated to achieve diverse leaf forms.

Functional analysis of WOX family genes in Dendrobium catenatum during growth and development.

The WUSCHEL-Related Homeobox (WOX) family is a group of transcription factors unique to plants that play an important role in regulating key developmental processes such as stem cell maintenance and organ morphogenesis. As a rare and valuable Chinese herb, Dendrobium catenatum has a unique epiphytic lifestyle and growth and developmental characteristics, and a functional investigation of its WOX family genes can help to further understand the conserved and specific development of D. catenatum. In this study, we analyzed the phylogeny, spatio-temporal expression pattern and heterologous expression function of D. catenatum WOX family genes (DcWOX). The results showed that members of the D. catenatum WOX gene family could be divided into three evolutionary branches with significantly different tissue expression profiles. In transgenic Arabidopsis, overexpression of DcWOX4 resulted in significant dwarfism, pinnately leaf margins, and delayed flowering for 2 weeks; overexpression of DcWOX9 resulted in plant dwarfing, serrated leaf margin, delayed flowering for 1 week, and even male and female sterility in strong phenotype plants; overexpression of DcWOX11 caused curl downward leaf. The abnormal morphogenesis of DcWOX4/9/11 overexpression Arabidopsis leaves are related to the down-regulation of TCP family genes, CUC family genes and the up-regulation of KNOX family genes; Postponement of flowering is related to down-regulation of early flowering genes such as FT, SOC1 and CO. Therefore, this study showed that D. catenatum WOX family genes have important functions in regulating plant morphogenesis, leaf development, flowering time and fertility, further expanding the understanding of the WOX gene family function, and providing clues for the conservation and specificity during orchid development and evolution.

New Insights from Solanum fernandesii (Solanaceae)

Solanum fernandesii is an unusual and important species of the genus Solanum, and it is the only known species within Solanum that has a petiolar gland. We provide new insights for this species endemic to Brazil, including a new record for the state of Piauí, Northeastern Brazil. S. fernandesii is distributed in the states of Piauí, Ceará, Bahia, Alagoas, Minas Gerais, and Pernambuco. Based on the use of online tools and field observations, its conservation status is classified as Least Concern for the Extension of Occurrence (754.583,610 km2) and Endangered for the Area of Occupancy (68.000 km2). We emphasize that serrated leaf margins, the presence of a petiole gland, and the shape of the calyx of fruits and seeds are important characteristics for the delimitation of this species. Taxonomic notes, field images, comments, and identification key for species of the genus Solanum in the study area are presented. Key words: Caatinga, Flora of Piauí, Gardneri Clade, Petiolar glands.

Ectopic Expression of BcCUC2 Involved in Sculpting the Leaf Margin Serration in Arabidopsis thaliana.

Leaf margin serration is a morphological characteristic in plants. The CUC2 (CUP-SHAPED COTYLEDON 2) gene plays an important role in the outgrowth of leaf teeth and enhances leaf serration via suppression of growth in the sinus. In this study, we isolated the BcCUC2 gene from Pak-choi (Brassica rapa ssp. chinensis), which contains a 1104 bp coding sequence, encoding 367 amino acid residues. Multiple sequence alignment exhibited that the BcCUC2 gene has a typical conserved NAC domain, and phylogenetic relationship analysis showed that the BcCUC2 protein has high identity with Cruciferae plants (Brassica oleracea, Arabidopsis thaliana, and Cardamine hirsuta). The tissue-specific expression analysis displayed that the BcCUC2 gene has relatively high transcript abundance in floral organs. Meanwhile, the expression profile of BcCUC2 was relatively higher in the '082' lines with serrate leaf margins than the '001' lines with smooth leaf margins in young leaves, roots, and hypocotyls. In addition, the transcript level of BcCUC2 was up-regulated by IAA and GA3 treatment, especially at 1-3 h. The subcellular localization assay demonstrated that BcCUC2 was a nuclear-target protein. Furthermore, leaf serration occurred, and the number of the inflorescence stem was increased in the transgenic Arabidopsis thaliana plants' overexpressed BcCUC2 gene. These data illustrated that BcCUC2 is involved in the development of leaf margin serration, lateral branches, and floral organs, contributing to further uncovering and perfecting the regulation mechanism of leaf serration in Pak-choi.

Two new species of Ribes (Grossulariaceae) from Peru

The genus Ribes (Grossulariaceae) has a center of diversity in the tropical Andes, especially in Peru. Several new species have been discovered in recent years and additional collections keep turning up material of undescribed species. In the present study we describe two additional new species, both from the wide-ranging species complex around Ribes andicola. Ribes lambayequensis comes from a known centre of diversity of the Andean plants, the Amotape-Huancabamba Zone, but represents the first species of the genus from Lambayeque. It differs most obviously from its geographical neighbor Ribes colandina by its two-coloured flowers in erect inflorescences (versus uniformly dark red flowers in pendulous racemes in R. colandina). The other new species is described from Apurímac and represents the first microendemic species of Ribes from this generally poorly explored region. It is a far southern outlier of the Ribes andicola group, which otherwise finds its southern range limit in the Department of La Libertad. Ribes apurimacensis differs from its closest allies in the Ribes andicola group by an exclusively glandular indument (no simple hairs) in combination with smaller leaves, a serrate leaf margin and dark red flowers.

Raphiocarpustaygiangensis (Gesneriaceae), a new species from central Vietnam.

Raphiocarpustaygiangensis, a new species of Gesneriaceae family discovered in Tay Giang District, Quang Nam Province, Central Vietnam, is here described and illustrated. The new species is diagnosed by the combination of its stem up to 2 m long, sericeous hairs on young stem, leaf petiole and adaxial mid-vein, sparsely and minutely serrate leaf margin, axillary inflorescence spreading along stem, sparsely long gland-tipped hairs on peduncle, pedicel, calyx, outside corolla and pistil, calyx 5-disparted from base, purplish white flower with purple stripes inside corolla tube, and dish-shaped stigma formed by 2 semi-orbicular lobes horizontally expanding. Distinct features of the new species and its morphologically closest congener, Rhaphiocarpusaxillaris, are compared and discussed. The conservation status of the described species is estimated as Vulnerable (VU D2) according to the IUCN Red List Criteria.

Brymela antioquiana S.P. Churchill &amp; J.J. Atwood (Pilotrichaceae) a new species from Colombia

A new species, B ry m ela a n tio q u ia n a S.P. Churchill &amp; J.J. Atwood, is described and illustrated from Colombia. The new species is superficially similar to B. p a rk e r ia n a (Hook. &amp; Grev.) W.R. Buck - a species from northern Amazonia, the Guianas and Lesser Antilles - in its weakly complanate habit and straight, oblong-lanceolate leaves. B ry m ela a n tio q u ia n a differs from B. p a rk e r ia n a in having: longer leaves (3.6-4.0 versus 2.1-3.2 mm); long-acuminate versus obtuse to acute leaf apices; more strongly undulate upper laminae; and entire to weakly serrulate leaf margins with simple teeth versus serrulate to moderately serrate leaf margins with occasionally bifid teeth. A key to the 13 species of B ry m ela is provided.

Enhanced genome-wide association reveals the role of YABBY11-NGATHA-LIKE1 in leaf serration development of Populus.

Leaf margins are complex plant morphological features that contribute to leaf shape diversity, which affects plant structure, yield, and adaptation. Although several leaf margin regulators have been identified to date, the genetic basis of their natural variation has not been fully elucidated. In this study, we profiled two distinct leaf morphology types (serrated and smooth) using the persistent homology mathematical framework (PHMF) in two poplar species (Populus tomentosa and Populus simonii, respectively). A combined genome-wide association study (GWAS) and expression quantitative trait nucleotide (eQTN) mapping were applied to create a leaf morphology control module using data from P. tomentosa and P. simonii populations. Natural variation in leaf margins was associated with YABBY11 (YAB11) transcript abundance in poplar. In P. tomentosa, PtoYAB11 carries a premature stop codon (PtoYAB11PSC), resulting in the loss of its positive regulation of NGATHA-LIKE1 (PtoNGAL-1) and RIBULOSE BISPHOSPHATE CARBOXYLASE LARGE SUBUNIT (PtoRBCL). Overexpression of PtoYAB11PSC promoted serrated leaf margins, enlarged leaves, enhanced photosynthesis, and increased biomass. Overexpression of PsiYAB11 in P. tomentosa promoted smooth leaf margins, higher stomatal density, and greater light damage repair ability. In poplar, YAB11-NGAL1 is sensitive to environmental conditions, acts as a positive regulator of leaf margin serration, and may also link environmental signaling to leaf morphological plasticity.

Eriobotryacrassifolia (Rosaceae), a new species from Yunnan Province, China.

The new species Eriobotryacrassifolia, collected from Yunnan Province, China, is characterised and illustrated. A phylogeny based on chloroplast genomes supported its closest affinity with E.tengyuehensis, while a phylogeny based on 197 single-copy nuclear genes supported its closest affinity with E.fragrans and E.deflexa. Morphologically, however, it resembles E.angustissima. Nevertheless, it can be easily distinguished from E.angustissima by its abaxially retroflexed and sharply serrate leaf margins, densely rusty tomentose inflorescences, and oblong or elliptic leaves.

BEGONIA HEMICARDIA (SECT. PETERMANNIA, BEGONIACEAE), A RESURRECTED HETEROTYPIC SYNONYM AND NOMEN NUDUM

The nomen nudum Begonia hemicardia Elmer ex Merr. (Begonia sect. Petermannia) was coined by A.D.E. Elmer in 1915. He annotated one of his collections (14366 from Mount Bulusan, Luzon) in the PNH herbarium with the name but did not formally publish it. E.D. Merrill in 1923 recognised the name as a synonym of Begonia binuangensis Merr. After thorough studies of living and preserved specimens and the relevant literature, we found Begonia hemicardia to be different from B. binuangensis. Begonia hemicardia is allied to a group of climbing Begonia in the Philippines with axillary inflorescences and numerous, subsymmetrical, ovate to lanceolate-ovate leaves, namely B. aequata A.Gray, B. binuangensis, B. edanoii Merr., B. gracilipes Merr., B. lagunensis Elmer, B. megacarpa Merr., B. sarmentosa L.B.Sm. &amp; Wassh. and B. wenzelii Merr. However, a combination of characters such as long internodes, large persistent stipules, serrate leaf margins, and long inflorescence with staminate flowers borne on a jointed rachis readily distinguish Begonia hemicardia from these other species, and we validly describe the new species here.

Tannin phenotyping of the Vitaceae reveals a phylogenetic linkage of epigallocatechin in berries and leaves.

Condensed tannins, responsible for berry and wine astringency, may have been selected during grapevine domestication. This work examines the phylogenetic distribution of condensed tannins throughout the Vitaceae phylogenetic tree. Green berries and mature leaves of representative true-to-type members of the Vitaceae were collected before 'véraison', freeze-dried and pulverized, and condensed tannins were measured following depolymerization by nucleophilic addition of 2-mercaptoethanol to the C4 of the flavan-3-ol units in an organic acidic medium. Reaction products were separated and quantified by ultrahigh pressure liquid chromatography/diode array detection/mass spectrometry. The original ability to incorporate epigallocatechin (EGC) into grapevine condensed tannins was lost independently in both the American and Eurasian/Asian branches of the Vitaceae, with exceptional cases of reversion to the ancestral EGC phenotype. This is particularly true in the genus Vitis, where we now find two radically distinct groups differing with respect to EGC content. While Vitis species from Asia are void of EGC, 50 % of the New World Vitis harbour EGC. Interestingly, the presence of EGC is tightly coupled with the degree of leaf margin serration. Noticeably, the rare Asian EGC-forming species are phylogenetically close to Vitis vinifera, the only remnant representative of Vitis in Eurasia. Both the wild ancestral V. vinifera subsp. sylvestris as well as the domesticated V. vinifera subsp. sativa can accumulate EGC and activate galloylation biosynthesis that compete for photoassimilates and reductive power.

Auxin-driven ecophysiological diversification of leaves in domesticated tomato.

Heterobaric leaves have bundle sheath extensions (BSEs) that compartmentalize the parenchyma, whereas homobaric leaves do not. The presence of BSEs affects leaf hydraulics and photosynthetic rate. The tomato (Solanum lycopersicum) obscuravenosa (obv) mutant lacks BSEs. Here, we identify the obv gene and the causative mutation, a nonsynonymous amino acid change that disrupts a C2H2 zinc finger motif in a putative transcription factor. This mutation exists as a polymorphism in the natural range of wild tomatoes but has increased in frequency in domesticated tomatoes, suggesting that the latter diversified into heterobaric and homobaric leaf types. The obv mutant displays reduced vein density, leaf hydraulic conductance and photosynthetic assimilation rate. We show that these and other pleiotropic effects on plant development, including changes in leaf insertion angle, leaf margin serration, minor vein density, and fruit shape, are controlled by OBV via changes in auxin signaling. Loss of function of the transcriptional regulator AUXIN RESPONSE FACTOR 4 (ARF4) also results in defective BSE development, revealing an additional component of a genetic module controlling aspects of leaf development important for ecological adaptation and subject to breeding selection.

Leiodontium geminoserratum (Hypnaceae, Bryophyta), a New Species from Thailand

Leiodontium geminoserratum S. He &amp; Chantanaorr. (Hypnaceae), a new species from Thailand, is described herein based on distinctive morphological features. The new species resembles L. gracile Broth. from China and Nepal, but differs most notably in having moderately complanate leafy stems and branches, prorate laminal cells, doubly serrate basal leaf margin, and axillary hairs with a globose distal cell. A full description and photographs of the new species are provided.

Molecular and morphological evidence for a new species of Pogostemon (Lamiaceae) from Hainan Island, China.

Pogostemonhainanensis, a new species of Lamiaceae from Hainan Island, China, is described. The phylogenetic position of the new species within Pogostemon was investigated based on analyses of the nuclear ribosomal internal transcribed spacer (nrITS) and five plastid markers (viz. matK, psbA-trnH, rbcL, rsp16, trnL-F). The results show that P.hainanensis is supported to be a member of subgenus Pogostemon and is sister to P.parviflorus, a species widely distributed from Eastern Himalaya, through the Indo-China peninsula to China. Morphologically, the new species can be distinguished from all the other taxa of subgenus Pogostemon in having long petioles usually 4.5‒11.5 cm in length, and the calyx teeth 2/3 to subequal as long as the calyx tube. The new species differs from P.parviflorus further by its obviously double serrate leaf margin, spikes of inflorescence usually 2.5–8.0 cm long, calyx 4‒5 mm long and corolla 6–7 mm long.

LATE MERISTEM IDENTITY1 regulates leaf margin development via the auxin transporter gene SMOOTH LEAF MARGIN1.

Plant leaves have evolved into diverse shapes and LATE MERISTEM IDENTITY1 (LMI1) and its putative paralogous genes encode homeodomain leucine zipper transcription factors that are proposed evolutionary hotspots for the regulation of leaf development in plants. However, the LMI1-mediated regulatory mechanism underlying leaf shape formation is largely unknown. MtLMI1a and MtLMI1b are putative orthologs of LMI1 in the model legume barrelclover (Medicago truncatula). Here, we investigated the role of MtLMI1a and MtLMI1b in leaf margin morphogenesis by characterizing loss-of-function mutants. MtLMI1a and MtLMI1b are expressed along leaf margin in a near-complementary pattern, and they redundantly promote development of leaf margin serrations, as revealed by the relatively smooth leaf margin in their double mutants. Moreover, MtLMI1s directly activate expression of SMOOTH LEAF MARGIN1 (SLM1), which encodes an auxin efflux carrier, thereby regulating auxin distribution along the leaf margin. Further analysis indicates that MtLMI1s genetically interact with NO APICAL MERISTEM (MtNAM) and the ARGONAUTE7 (MtAGO7)-mediated trans-acting short interfering RNA3 (TAS3 ta-siRNA) pathway to develop the final leaf margin shape. The participation of MtLMI1s in auxin-dependent leaf margin formation is interesting in the context of functional conservation. Furthermore, the diverse expression patterns of LMI1s and their putative paralogs within key domains are important drivers for functional specialization, despite their functional equivalency among species.

Studies on Physico-chemical characters of Thai Apple ber (Ziziphus mauritiana Lamk.) grown in Assam

An experiment was carried out during 2017-19 to study the morpho-physical and bio-chemical characters of Thai Apple ber (Ziziphus mauritiana Lamk.) grown in Assam. The leaves of Thai Apple ber fruits collected from different locations of Assam showed elliptic shape with serrate leaf margin, obtuse apex and oblique base. The colour of mature leaves was observed to be dark green. The leaf length, leaf breadth and petiole length of Thai Apple ber fruits shows a great variations among all collection. The plant of Gela Pukhuri and Simen Chapori recorded early flowering and harvesting among the Thai Apple ber plants of other locations in the present study. The fruits of Boitamari (BC-8) recorded longest fruit (5.10cm) while, maximum fruit weight (53.08g) was recorded in BC-1 (Simen Chapori). The shape and surface of seeds was found to be ovate and warty and pulp-stone ratio ranged from 18.76 - 23.28.The biochemical analysis reveals that the quality characters like moisture content, TSS, titratable acidity, TSS-acid ratio and ascorbic acid content differed. Total sugar (6.37 - 7.81%) and reducing sugar (2.44 - 3.06%) contents varied significantly among the Thai Apple ber fruits of different locations. The highest vitamin A (16.08 μg/100g) were found in Gela Pukhuri (BC-3) and highest protein (0.87g/100g) was found in BC-2 (Bongalmora). The calcium and phosphorus contents of the Thai Apple ber fruits ranged from 20.48mg/100g to 23.50mg/100g and 24.08mg/100g to 25.25mg/100g, respectively. It can be concluded that Thai Apple apple ber fruits can successfully be grown under sub-tropical area of Assam. The ber fruits collected from Simen Chapori (BC-1) was found best in terms of biochemical composition i.e. TSS, TSS/ acid ratio, total sugar, reducing sugar and moisture content.