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Organ boundaries serve several important roles in development, but the mechanisms downstream of boundary-defining factors are not well understood. In Chapter 1 of my dissertation, I show the Arabidopsis transcription factor LOB regulates leaf angle via a phototropism-dependent mechanism, reducing phototropic responses at the base of the leaf. LOB and other boundary-defining transcription factors also regulate numerous cell wall genes, implying a biophysical mechanism is an important aspect of boundary function. Given the inherent challenges of measuring cell wall mechanics in the Arabidopsis leaf-meristem boundary, I used a different system, the maize ligular region, which is highly amenable to AFM experiments. In Chapter 2, I characterized mechanical patterns during the development of the ligular region. My findings are consistent with the existence of a cell wall rigidification program in the boundary, which correlates with patterns of growth, cell division, and auxin dynamics. In Chapter 3, I measured epidermal cell geometry and cell wall stiffness over a wide area of the maize leaf. I found that the establishment of the boundary in the maize leaf was linked not just to local changes, but to broader growth and mechanical patterns outside the boundary. This suggests that coordination between the boundary and adjacent leaf zones is involved in the morphogenesis of the maize leaf. My findings further our understanding of how plant boundaries regulate growth.

Lombok upland rice is one of the cultivars that have the potential as a genetic source. However, Lombok upland rice is almost rarely found. Therefore, conservation was carried out through morphological characterization to provide genetic information. This study aimed to describe the characteristics of six Lombok upland rice cultivars, namely, Reket Putek Bulu, Reket Putek Buntung, Reket Bireng Bulu, Reket Bireng Buntung, Pare Beaq Sapit, and Beaq Ganggas. A completely randomized design was used, consisting of these six Lombok upland rice cultivars as treatments. Two superior cultivars were also used for comparison. The study revealed sufficient divergence for various qualitative and quantitative traits. Pare Beaq Sapit and Beaq Ganggas shared common morphological characters, and both were tall plants. The auricle and ligule colors of Reket Bireng Bulu were different from those of the other cultivars. Reket Putek Buntung had the latest flowering and harvesting age. Reket Putek Bulu and Reket Bireng Buntung had a high number of productive tillers. Six cultivars of Lombok upland rice were characterized to have morphological diversity, so that they are expected to be used as genetic material in rice plant breeding, thereby developed to avoid extinction.

A newly discovered species of the genus Agrostis from Western Himalaya is here described and illustrated. The new species, Agrostis barikii, is considered as a member of Agrostis pilosula group and morphologically closely allied to Agrostis griffithiana by its palea 2/3 the length of the lemma and well-developed awn. However, they differ from the latter by means of the shape of the ligule, length of the lower glume, apex of the lemma, and size of anthers. Data on distribution, habitat and phenology is given along with a photo plate and an illustration.

A new species of Erythroxylum from Colombia and Panamá is described and illustrated. The new species is morphologically similar to Erythroxylum acuminatum from Ecuador, Peru, Brazil, and Bolivia but differs from this species by its longer and caducous stipules, with two longer lateral setae, and by the underdeveloped anterior ligule of the petals.

Genetic analysis of genes that regulate the color pigmentation of sterile lemma and apiculus has been conducted. “Josaengjado” has small and round grains with purple leaf, sterile lemma and apiculus. In the F2 population from a cross between Josaengjado and Daeribbyeo 1, 246 and 182 plants exhibited purple and straw-white sterile lemma, respectively. It fitted a 9:7 segregation ratio indicating that two complementary genes control the pigmentation in sterile lemma and apiculus. Genetic analysis was performed using the F2:3 and KASP (Kompetitive Allele-Specific PCR) markers. Genes for the coloration of leaf sheath, ligule, sterile lemma, and apiculus were detected on chromosomes 1 and 6. Sequence comparison showed a single nucleotide substitution C (Josaengjado) to A (Daeribbyeo 1) in the second exon of the Rd gene on chromosome 1 leading to a premature stop in Daeribbyeo 1. In C1, a 3-bp deletion in the second exon was detected in Daeribbyeo 1. Haplotype analysis was performed in the Rd and C1 genes of the 78 rice accessions. 78 accessions were divided into 14 groups. A total of 11 and 1 mutation sites were detected in OsC1 and Rd, respectively. The haplotype analysis also confirmed that two complementary genes, Rd and OsC1 are necessary to express anthocyanin pigmentation in sterile lemma and apiculus. To our knowledge, this is the first report to identify genes for the coloration of sterile lemma in rice.

Parahyparrhenia khannae, a new species of Andropogoneae (Poaceae: Andropogoneae) from the grassland of Ratlam and Jhabua districts of Madhya Pradesh, India is described and illustrated. The new species is similar to the Indian endemic species P. bellariensis in having dorsal groove in lower glume of sessile spikelet, but differs in having shorter plant height, lacerate membranous ligule, shorter leaf blade and raceme length, fewer homogamous spikelets, shorter sessile spikelet and anther length.

Grass inflorescence development is diverse and complex and involves sophisticated but poorly understood interactions of genes regulating branch determinacy and leaf growth. Here, we use a combination of transcript profiling and genetic and phylogenetic analyses to investigate tasselsheath1 ( tsh1 ) and tsh4 , two maize genes that simultaneously suppress inflorescence leaf growth and promote branching. We identify a regulatory network of inflorescence leaf suppression that involves the phase change gene tsh4 upstream of tsh1 and the ligule identity gene liguleless2 ( lg2 ). We also find that a series of duplications in the tsh1 gene lineage facilitated its shift from boundary domain in nongrasses to suppressed inflorescence leaves of grasses. Collectively, these results suggest that the boundary domain genes tsh1 and lg2 were recruited to inflorescence leaves where they suppress growth and regulate a nonautonomous signaling center that promotes inflorescence branching, an important component of yield in cereal grasses.

The glume is an organ of the maize spikelet and plays important roles in anther and kernel development. Vestigial glume1 (Vg1) is a classic mutant associated with ligule and glume development. Here we report the phenotypic characterization, fine mapping, and candidate gene analysis of the Vg1 mutant. Vg1 is a semi-dominant and pleiotropic gene, and also affects plant height, ear height, and tassel length. Vg1 ligule degeneration begins at the first leaf, and the Vg1 tassel and ear can be distinguished from those of wild-type plants when their lengths reach respectively 55 mm and 51 mm. Using a BC3 mapping population of 11,445 plants, we delimited the Vg1 functional site to an interval of 7.4 kb, flanked by the markers InDelLM and CRM6. A putative cyclopropane fatty-acid synthase gene (ZmCPA-FAS1) was hypothesized to underlie the mutant phenotype. We detected a Helitron insertion in the sixth intron of ZmCPA-FAS1. Its presence caused abnormal alternative splicing of ZmCPA-FAS1 that conferred new characteristics on the Vg1 mutant. These findings are a basis for further discovery of the molecular mechanism underlying glume development and a potential guide for maize breeding of small-glume varieties, especially sweet corn breeding. Keywords: Vestigial glume1, Fine mapping, Candidate gene analysis, ZmCPA-FAS1, Glume development

Less space but greater maize yield To meet increasing demands for food, modern agriculture works with increasingly dense plantings. Tian et al. identified a gene in teosinte, the wild ancestor of maize, and used it to alter maize such that the plant has a narrower architecture that nonetheless allows leaves access to sunlight (see the Perspective by Hake and Richardson). The yield advantage only becomes evident with the high-density plantings characteristic of modern agriculture, perhaps explaining why this gene was not brought into the fold during the previous millennia of maize domestication. Science , this issue p. 658 ; see also p. 640

Dendrocalamus menghanensis P.Y.Wang & D.Z.Li, a new species of woody bamboos endemic to south Yunnan, China, is described and illustrated. The new species is morphologically similar to D. semiscandens and D. birmanicus but differs in having a reflexed culm sheath blade, 10 mm high culm sheath ligule, 1 mm high leaf sheath ligule, 4 florets and 1 glume.

Bacterial leaf blight (BLB) is one of the major diseases of rice plants mainly in irrigated rice caused by pathogenic bacteria Xanthomonas oryzae pv. oryzae (Xoo). Leaf morphology becomes an interesting character to be investigated due to its relationship with the intensity of BLB disease, because the leaf is the part of plant which is infected by the bacteria. The purpose of this research was to obtain information on the variability of leaf morphology and its correlation with BLB diseases, to support plant breeding program of BLB disease-resistant rice varieties. A total of 25 local rice accessions were characterized phenotypically. Leaf morphological characters were examined without replication, while in Xoo resistance (pathotype IV) test was done by using randomized block design with three replications. Characterization on leaf morphology indicated that all local rice accessions had green collar, transparent auricle color, white ligule color, and 2-cleft ligule shape. In four weeks after inoculation, four accessions (Ketan Lomah Hitam, Bumbuy Inih, Gonggoi, and Waren) showed disease severity percentages of BLB diseases on the range between 13-16%. These observations indicated that these accessions had slightly sussceptible response to BLB diseases wich were better than the other accessions. Leaf-surface morphology was positively correlated with BLB disease. The four accessions were feathery or slightly hairy with a short-sized leaf. The results of this research could be used as a reference for developing of BLB resistance rice varieties.

Naive MAK, Demayo CG, Alejandro GJD. 2021. Short Communication: New insights into the morphology and distribution of the Philippine endemic Etlingera pilosa (Zingiberaceae). Biodiversitas 22: 3175-3179. Etlingera pilosa Poulsen & Docot, only known in Negros Oriental and Negros Occidental of Visayas islands, Philippines, is recorded in the island of Mindanao for the first time, thus, extending its distributional range. The species is characterized by having sericeous ligule; leaves subsessile, narrowly obovate, coriaceous, glabrous adaxially, densely pubescent abaxially; inflorescence up to 12 cm long; flowers yellow, 3.0–3.2 cm long; subglobose to obovoid, pilose, with wart like blunt spines fruit; and seeds irregularly subglobose to oblate, black, fully embedded in juicy sour-sweet white aril. This species closely resembles E. pubimarginata but differs in having densely pubescent abaxial leaf, sericeous ligule and subglobose to obovoid, pilose, with wart like blunt spines fruit. Here, we provide a detailed description, comparison with its allied species, colored photographs to aid identification, a distribution map, an IUCN conservation assessment and a taxonomic key to the Mindanao Etlingera species.

Two new species and one new record species of the genus Pseudonereis are described from specimens collected from ecological surveys of coasts of Taiwan and an offshore island during the past 15 years: P. jihueiensis n. sp., P. kihawensis n. sp., and P. trimaculata. Epitokes of P. jihueiensis n. sp. and P. trimaculata are also described. Pseudonereis jihueiensis n. sp. can be distinguished from congeners by having edentate jaws, χ-shaped ridge pattern of Areas VI–V–VI, parapodial morphology (i.e., length ratio of dorsal cirrus to dorsal ligule or presence of small pennant-like dorsal ligule, shape of dorsal ligule in certain region of chaetigers), and no heterogomph spinigers in the subacicular fascicle of the neuropodia. Pseudonereis kihawensis n. sp. differs from congeners by having crescent-shaped pointed-bars in Area VI, λ-shaped ridge pattern of Areas VI–V–VI, parapodial morphology (i.e., length ratio of dorsal cirrus to dorsal ligule or presence of small pennant-like dorsal ligule or shape of dorsal ligule in certain region of chaetigers), and no heterogomph spinigers in the subacicular fascicle of the neuropodia. Pseudonereis trimaculata, a species originally described from Indonesia, is reported from Taiwan for the first time. A table of key characters for all species of Pseudonereis is provided.

Background The extreme southwest of Australia is a biodiversity hotspot region that has a Mediterranean-type climate and numerous endemic plant and animal species, many of which remain to be properly delimited. We refine species limits in Anarthria, a Western Australian endemic genus characterised by the occurrence of the greatest number of plesiomorphic character states in the restiid clade of Poales. In contrast to many other groups of wind-pollinated Australian Poales, Anarthria was traditionally viewed as having well-established species limits. All six currently recognised species, which are conspicuous members of some Western Australian plant communities, were described in the first half of the 19th century. They are traditionally distinguished from each other mainly using quantitative characters. Methods We examined extensive existing herbarium specimens and made new collections of Anarthria in nature. Scanning electron microscopy and light microscopy were used to study leaf micromorphology. Molecular diversity of Anarthria was examined using a plastid (trnL-F) and a low-copy nuclear marker (at103). This is the first study of species-level molecular diversity in the restiid clade using a nuclear marker. Results Material historically classified as Anarthria gracilis R.Br. actually belongs to three distinct species, A. gracilis s.str., A. grandiflora Nees and A. dioica (Steud.) C.I.Fomichev, each of which forms a well-supported clade in phylogenetic analyses. Both segregate species were described in the first half of the 19th century but not recognised as such in subsequent taxonomic accounts. Anarthria dioica was first collected in 1826, then wrongly interpreted as a species of Juncus (Juncaceae) and described as Juncus dioicus. We provide a formal transfer of the name to Anarthria and for the first time report its clear and qualitative diagnostic characters: an extremely short leaf ligule and distinctive pattern of leaf epidermal micromorphology. A long ligule is present in A. gracilis s.str. and A. grandiflora. These species differ from each other in leaf lamina morphology and anatomy and have mostly non-overlapping distribution ranges. The narrower definition of species provides a basis for future phylogeographic analyses in Anarthria. Our study highlights a need for more extensive use of nuclear DNA markers in Restionaceae. The use of the low copy nuclear marker at103 allowed a clade comprising all three ligulate species of Anarthria to be recognised. The ligule character is used here for the first time in the taxonomy of Anarthria and merits special attention in studies of other restiids. In general, our study uncovered a superficially hidden but, in reality, conspicuous diversity in a common group of wind-pollinated plants in the southwest of Western Australia.

SALASIAH, M. & MEEKIONG, K. 2020. Plagiostachys strobilifera var. conica, a new variety from Sarawak, Borneo. Reinwardtia 19(2): 109‒116. ‒‒ The new taxon varies from Plagiostachys strobilifera var. strobilifera in the broader lanceolate leaves, the bilobed ligule, the longer calyx, the rounded anther crests, the oblong lateral staminodes, and the non-free apical bracteole with conical apex (which gives the taxon its epithet). A key to species of Bornean Plagiostachys is also provided, along with a conservation assessment.

Amomum arunachalense Hareesh & M. Sabu sp. nova (Zingiberaceae) is described from Arunachal Pradesh, northeastern India. It is similar to A. maximum, but differs from the latter by having a white rhizome with a pale brown center, an entire ligule, a labellum without lateral staminodes, an obtuse stamen crest and a non-winged, foveolate fruit. A detailed description of the plants along with photographs are provided.

Zingiber porphyrochilum Y.H. Tan & H.B. Ding sp. nova (Zingiberaceae) from Yunnan, China is described and illustrated. It is similar to Z. densissimum in its bilobed ligule and flower shape but differs from it by having a longer clumped pseudostem (1.5–2.5 m tall vs. solitary, 0.4–0.7 m tall), longer ligules (3–11 mm long vs. ca. 3 mm long), brownish yellow corolla lobes (vs. pure white), labellum and lateral staminodes brownish yellow at the base, and bright clear red to dark purplish towards the apex and margins (vs. pure white).

Antecedentes y Objetivos: Bouteloua es uno de los géneros más importantes en los pastizales de Norteamérica, especialmente en México, donde se distribuye 92% de los taxones descritos para este grupo, 25 de los cuales son endémicos. Uno de estos es Bouteloua reederorum, que ha sido confundido con B. stolonifera, ocasionando que sea reportado en estados de la república en donde no se encuentra. El objetivo del presente trabajo es aclarar la identidad de B. reederorum y proporcionar una descripción morfológica detallada con fotografías de estructuras importantes para su identificación, así como un mapa de distribución para esta especie.Métodos: Se revisó el material depositado en los herbarios ARIZ, HUAA, HUAP, HUMO, IEB, INEGI, MEXU, XAL y las colecciones digitales MO, P y US y la plataforma JSTOR, para obtener registros de B. reederorum. Con base en esta información se determinaron los puntos de colecta, que fueron visitados de septiembre de 2017 a agosto de 2019 en busca de poblaciones de esta especie, donde se colectaron ejemplares. El material colectado fue identificado y revisado para elaborar una descripción morfológica con fotografías de características importantes para la identificación de la especie. Con los datos tomados en campo, material de herbario y colecciones digitales se realizó un mapa de distribución de B. reederorum.Resultados clave: Bouteloua reederorum y B. stolonifera pueden distinguirse fácilmente por caracteres morfológicos como la ramificación de sus inflorescencias y la forma de la lígula. Bouteloua reederorum se encuentra restringida al Valle de Tehuacán-Cuicatlán, ubicado entre Puebla y Oaxaca. Aunque generalmente las espiguillas masculinas de B. reederorum no tienen flósculos rudimentarios, en raras ocasiones pueden desarrollar uno, similar al de las espiguillas femeninas.Conclusiones: Bouteloua reederorum es distinta de Bouteloua stolonifera (= Cyclostachya stolonifera). Es necesario realizar estudios fenológicos para determinar si B. reedeorum puede ser dioica.

The formation of developmental boundaries is a common feature of multicellular plants and animals, and impacts the initiation, structure and function of all organs. Maize leaves comprise a proximal sheath that encloses the stem, and a distal photosynthetic blade that projects away from the plant axis. An epidermally derived ligule and a joint-like auricle develop at the blade/sheath boundary of maize leaves. Mutations disturbing the ligule/auricle region disrupt leaf patterning and impact plant architecture, yet it is unclear how this developmental boundary is established. Targeted microdissection followed by transcriptomic analyses of young leaf primordia were utilized to construct a co-expression network associated with development of the blade/sheath boundary. Evidence is presented for proximodistal gradients of gene expression that establish a prepatterned transcriptomic boundary in young leaf primordia, before the morphological initiation of the blade/sheath boundary in older leaves. This work presents a conceptual model for spatiotemporal patterning of proximodistal leaf domains, and provides a rich resource of candidate gene interactions for future investigations of the mechanisms of blade/sheath boundary formation in maize.

The first of a two-part taxonomic revision of the morphologically complex Schoenus cuspidatus and allies group is presented. This revision builds on two recent taxonomic works of which the first transferred 24 southern African species from Tetraria and Epischoenus into Schoenus, and the second revised the taxonomy of the Schoenus compar – Schoenus pictus and allies group, as well as described three new species from South Africa. Here, we use data from recent field collections and a review of specimens from 12 herbaria to revise the delimitations and distributions of three species (Schoenus bolusii, Schoenus exilis and Schoenus graminifolius). In addition, we describe seven new species: six of which are endemic to the Cape Floristic Region (Schoenus calceolus, Schoenus crassiculmis, Schoenus submarginalis, Schoenus prophyllus, Schoenus purpurascens and Schoenus quartziticus), while the seventh is endemic to the Eastern Cape and KwaZulu Natal Provinces of South Africa (Schoenus limosus). We also resolve nomenclatural and species delimitation issues in Schoenus auritus and Schoenus ligulatus, with Schoenus autumnalis and Schoenus variabilis being subsumed in an enlarged circumscription of Schoenus ligulatus. Species in the Schoenus cuspidatus group are caespitose, perennial graminoids, with scapose and terete culms. However, there are differences in sheath and ligule type, which can be either firm or membranaceous, as well as leaf type, which vary from channelled and terete to non-channelled and flat. Importantly, differences in spikelet and nutlet shape distinguish many of the species in this group. A taxonomic key is presented, the nomenclature is updated, and detailed descriptions and distribution maps are provided for these 12 Schoenus species.

The article presents the results of a study of the ligule morphology of both vegetative and reproductive leaves of four species of Selaginella, i.e. S. delicatula, S. ganguliana, S. plana and S. tenera, occurring in India. Ligules of S. ganguliana, S. plana and S. tenera are described for the first time, and the occurrence of shuttlecock-like ligules is described for the first time. Ligule shape is generally constant across the species studied but some minor morphological variations are observed within species. However, in combination with other morphological characters, the ligule may be a useful tool in the taxonomic delimitation of closely related Selaginella species. In addition, we propose that ligule size may be influenced by the habitat conditions, whereas the presence of glandular cells at their tip margins possibly indicate a water secreting function.

The name Ficinia gracilis has been misapplied to multiple taxa occurring from the Cape Peninsula through the Drakensberg into Afromontane habitats in eastern Africa. This broad circumscription encompasses at least five species (F. filiformis, F.rigida, F.gracilis, F.cinnamomea and an additional unnamed taxon). These taxa have been suggested (e.g. Gordon-Gray 2008) to be inseparable on gross morphology, and recent floras apply the broad concept of F.gracilis. This study re-examines species delineation, using ecology, gross morphology, and studies of nutlet morphology based on scanning electron microscopy, recognizing three groups of species, namely, F.gracilis (including F.undosa; sticky leaf sheaths, rugose nutlets, in grasslands), F.cinnamomea (together with the unnamed taxon; non sticky leaf sheaths, minutely papillose nutlets, in grasslands) and F.filiformis(together with F.rigida; sticky leaf sheaths, rugose nutlets, in fynbos). Ficinia eligulata Gordon-Gray ex Muasya is named and described, diagnosed by filiform culms and leaves, non sticky leaf sheaths and with leaves lacking a ligule, and minutely papillose nutlets.

The shoot apical and axillary meristems control shoot development, effectively influencing lateral branch and leaf formation. The barley (Hordeum vulgare) uniculm2 (cul2) mutation blocks axillary meristem development, and mutant plants lack lateral branches (tillers) that normally develop from the crown. A genetic screen for cul2 suppressors recovered two recessive alleles of ELIGULUM-A (ELI-A) that partially rescued the cul2 tillering phenotype. Mutations in ELI-A produce shorter plants with fewer tillers and disrupt the leaf blade-sheath boundary, producing liguleless leaves and reduced secondary cell wall development in stems and leaves. ELI-A is predicted to encode an unannotated protein containing an RNaseH-like domain that is conserved in land plants. ELI-A transcripts accumulate at the preligule boundary, the developing ligule, leaf margins, cells destined to develop secondary cell walls, and cells surrounding leaf vascular bundles. Recent studies have identified regulatory similarities between boundary development in leaves and lateral organs. Interestingly, we observed ELI-A transcripts at the preligule boundary, suggesting that ELI-A contributes to boundary formation between the blade and sheath. However, we did not observe ELI-A transcripts at the axillary meristem boundary in leaf axils, suggesting that ELI-A is not involved in boundary development for axillary meristem development. Our results show that ELI-A contributes to leaf and lateral branch development by acting as a boundary gene during ligule development but not during lateral branch development.

Research into the basic qualitative characteristics (phens), their distribution and combinations (morphotypes) was undertaken in order to reveal the genetic diversity with respect to section Stenopoa in Asian Russia. About one and half thousands occurrences have been revealed, using herbarium samples and literature data, 1144 were involved in analysis. Four key characters have been used as phonetic markers: the presence or absence of the tuft of hairs on the lemma callus, rachilla surface, ligule length, and lemma surface between veins. Based on these characters and taking into account their xeromorphic level (4 character states), 46 different morphotypes among 96 possible ones were found; 24 morphotypes among 46 (56.5%) are suggested to be of hybrid origin, and 239 (20.89%) among 1144 investigated individuals seem to be of hybrid origin as well. High phenetic diversity of Stenopoa bluegrass indicated indirectly their high genetic diversity in Asian Russia. The highest morphological diversity and ...

An Asian species of Perinereis, which has been regarded as a local population of a cosmopolitan species P. cultrifera ( Grube, 1840 ) (type locality: Italy), is described as a new species, P. euiini., based on Korean specimens. This new species is distinguishable from P. cultrifera and other similar species such as P. floridana ( Ehlers, 1868 ) (type locality: USA), P. anderssoni Kinberg, 1866 (type locality: Brazil), and P. helleri ( Grube, 1878 ) (type locality: Philippines) by the character combination of the absence of lateral group of paragnaths in area III on the proboscis, the presence of small notopodial prechaetal lobe in anterior parapodia, and the greatly expanded dorsal ligule in posterior parapodia. All previous records of "P. cultrifera" from eastern Asia (Taiwan, China, Japan, and Korea) are judged to belong to P. euiini sp. nov., leading to the conclusion that P. cultrifera is not a cosmopolitan species. Specimens previously identified as P. cultrifera var. floridana (or P. cultrifera floridana) in eastern Asia are also judged to belong to P. euiini sp. nov., although they have different paragnath number in area V (one instead of three). Their aberrant paragnath number was regarded as an intraspecific variation of P. euiini sp. nov. The comparison of DNA sequences of the mitochondrial cytochrome c oxidase subunit I (COI) between P. euiini sp. nov. and "P. cultrifera" from China and Portugal also supports the erection of the new species.

Phragmites australis (common reed) is a widespread perennial grass of wetland habitats, with cryptic native and introduced subspecies in North America. We determined the relative abundance of the subspecies and the distributions of plastid DNA haplotypes throughout British Columbia, Canada, at the northwestern distribution limit of common reed in North America. Of 203 specimens assigned to subspecies using molecular markers, we identified only 9 plants as the introduced ssp. australis; all remaining samples were the native ssp. americanus. The two subspecies co-occurred at only one locality. We identified four native haplotypes (one widespread in British Columbia and three others more localized) and two introduced haplotypes. Using plants of known haplotype, we assessed the utility of different morphological traits and trait combinations for distinguishing native and introduced subspecies in this geographic region. No single morphological trait was diagnostic, but principal components analysis and identification indices based on combinations of traits consistently separated the native and introduced subspecies in our sample. Two- or three-trait combinations of ligule length, lemma length and stem anthocyanic coloration gave the best separation. These indices could reduce the need for confirmation of the introduced subspecies using molecular tools, facilitating efforts to monitor and control this invasive plant.

The fruits of Euterpe precatoria, popularly known as acai palm, have been commercially exploited for use in food and beverages because of their medicinal and energetic properties. However, despite the growing demand, little is known about the seeds germination, until now, its main form of propagation. In this context, we have characterized the structure of the zygotic embryo and described temporally the germination process of E. precatoria with emphasis on the morpho-anatomical and histochemical aspects. For this end, we have collected and analyzed zygotic embryo and seedlings samples before sowing and at different periods after sowing-2, 4, 6, 8, 10, 15, 20, 30, 40, 50, and 60 days. The embryo has an oblique embryonic axis and mainly protein reserves. Seed germination is classified as cryptocotyledonar, hypogeal, and adjacent ligular and we observed seedlings at 20 days after sowing (33.3%), although anatomical evidence of the beginning of the germination process have been observed at 15 days. The day-20 was histologically marked by the expansion of the ligule, beginning of second eophyll differentiation, and complete root protrusion. This stage was characterized by the total consumption of protein reserves and increased starch grains. The occurrence of 100% of root and ligula emission was verified at day-60, which characterizes a slow and heterogeneous process. The morphological marker of the E. precatoria germination is the exit of the proximal region (cotyledonary petiole) of the embryo from within the seed by the lifting of the operculum and the species has some peculiarities, such as the presence of high concentrations of phenolic compounds and idioblasts before and throughout the germination process, and starch grains located on the embryonic axis. We can verify that the consumption of protein reserves of the embryo is related to the energy supply necessary for root protrusion.

Zingiber natmataungense S.S.Zhou & R.Li (Zingiberaceae), a new species from Natma Taung National Park, Chin State, Myanmar, is described and illustrated. The new species is morphologically similar to Z. yunnanense, but differs by: leaf blade abaxially light green, glabrous, ligule sparsely pubescent, ca. 2–3 mm, bracts glabrous; calyx white 20–21 × 3.2–3.5 mm, glabrous, apex obviously 3-toothed; corolla tube white, ca. 3.9–4.1 cm, labellum lateral lobes, ca. 1.5–1.7 × 0.6–0.7 cm; stamen with sparse pubescent, filament white, glabrous,1–2 mm; anther connective appendage yellowish proximally, purplish distally; ovary white, sparsely white pubescent, epigynous glands, ca. 6–7 mm long, tapered, apex whorled, yellow. This new species is also similar to Z. teres, but has a different flower colour.

Objetivo: El objetivo del presente estudio fue caracterizar la morfología de 15 accesiones de pastos de la especie Pennisetum purpuereum. Diseño/metodología/aproximación: La caracterización morfológica de 15 accesiones de pastos del Banco de Germoplasma del Campo Experimental Rosario Izapa se realizó en la fase vegetativa con base en 28 caracteres cualitativos y cuantitativos. Se utilizaron diez plantas por accesión. Se determinó valores promedio, mínimo, máximo y coeficiente de variación para datos cuantitativos y moda para datos cualitativos. La base de datos promedio y moda se utilizó para efectuar un análisis de conglomerados jerárquico con la distancia de Gower y el método de Ward. Resultados: Las variables cuantitativas de los pastos presentaron poca variabilidad (coeficiente de variación menor a 25 %), mientras las variables cualitativas que presentaron variación entre los pastos fueron habito de crecimiento; color y forma del tallo; posición, disposición, forma, color y borde de foliolo; color de la nervadura adaxial y abaxial; pubescencia de foliolo en la parte adaxial y abaxial; posición, color y pubescencia de la vaina; tipo y color de lígula; y profilo. Las 15 accesiones de Pennisetum purpureum se agruparon en 2 grupos, los cuales contrastan principalmente por el profilo y posición del foliolo. Limitaciones del estudio/implicaciones: Para una mayor precisión sobre la diversidad morfológica de los pastos, es necesario realizar la caracterización de la inflorescencia y espícula. Hallazgos/conclusiones: Las accesiones de pastos Pennisetum purpureum del Banco de Germoplasma del Campo Experimental Rosario Izapa presentaron diversidad morfológica aceptable con base en 28 caracteres.

Leaf morphogenesis requires growth polarized along three axes - proximal-distal, medial-lateral and abaxial-adaxial. Grass leaves display a prominent proximal-distal (P-D) polarity consisting of a proximal sheath separated from the distal blade by the auricle and ligule. Although proper specification of the four segments is essential for normal morphology, our knowledge is incomplete regarding the mechanisms which influence P-D specification in monocots like maize (Zea mays). Here we report the identification of the gene underlying the semi-dominant, leaf patterning, maize mutantHairy Sheath Frayed1(Hsf1).Hsf1plants produce leaves with outgrowths consisting of proximal segments – sheath, auricle and ligule – emanating from the distal blade margin. Analysis of three independentHsf1alleles revealed gain-of-function missense mutations in the ligand binding domain of the maize cytokinin (CK) receptorZea mays Histidine Kinase1(ZmHK1)gene. Biochemical analysis and structural modeling suggest the mutated residues near the CK binding pocket affect CK binding affinity. Treatment of wild type seedlings with exogenous CK phenocopied theHsf1leaf phenotypes. Results from expression and epistatic analyses indicated theHsf1mutant receptor appears to be hypersignaling. Our results demonstrate that hypersignaling of CK in incipient leaf primordia can reprogram developmental patterns in maize.SummaryIncreased cytokinin signaling in the maizeHairy Sheath Frayed1mutant modifies leaf development leading to changes in pattering, growth and cell identity.

Liguleless narrow1 encodes a plasma membrane-localized receptor-like kinase required for normal development of maize (Zea mays) leaves, internodes, and inflorescences. The semidominant Lgn-R mutation lacks kinase activity, and phenotypic severity is dependent on inbred background. We created near isogenic lines and assayed the phenotype in multiple environments. Lgn-R plants that carry the B73 version of Sympathy for the ligule (Sol-B) fail to grow under hot conditions, but those that carry the Mo17 version (Sol-M) survive at hot temperatures and are significantly taller at cool temperatures. To identify Sol, we used recombinant mapping and analyzed the Lgn-R phenotype in additional inbred backgrounds. We identified amino acid sequence variations in GRMZM2G075262 that segregate with severity of the Lgn-R phenotypes. This gene is expressed at high levels in Lgn-R B73, but expression drops to nonmutant levels with one copy of Sol-M. An EMS mutation solidified the identity of SOL as a maize homolog of Arabidopsis (Arabidopsis thaliana) ENHANCED DISEASE RESISTANCE4 (EDR4). SOL, like EDR4, is induced in response to pathogen-associated molecular patterns such as flg22. Integrated transcriptomic and phosphoproteomic analyses suggest that Lgn-R plants constitutively activate an immune signaling cascade that induces temperature-sensitive responses in addition to defects in leaf development. We propose that aspects of the severe Lgn-R developmental phenotype result from constitutive defense induction and that SOL potentially functions in repressing this response in Mo17 but not B73. Identification of LGN and its interaction with SOL provides insight into the integration of developmental control and immune responses.

The morphological development of the leaf greatly influences plant architecture and crop yields. The maize leaf is composed of a leaf blade, ligule and sheath. Although extensive transcriptional profiling of the tissues along the longitudinal axis of the developing maize leaf blade has been conducted, little is known about the transcriptional dynamics in sheath tissues, which play important roles in supporting the leaf blade. Using a comprehensive transcriptome dataset, we demonstrated that the leaf sheath transcriptome dynamically changes during maturation, with the construction of basic cellular structures at the earliest stages of sheath maturation with a transition to cell wall biosynthesis and modifications. The transcriptome again changes with photosynthesis and lignin biosynthesis at the last stage of sheath tissue maturation. The different tissues of the maize leaf are highly specialized in their biological functions and we identified 15 genes expressed at significantly higher levels in the leaf sheath compared with their expression in the leaf blade, including the BOP2 homologs GRMZM2G026556 and GRMZM2G022606, DOGT1 (GRMZM2G403740) and transcription factors from the B3 domain, C2H2 zinc finger and homeobox gene families, implicating these genes in sheath maturation and organ specialization.

To explore the potential utilization of Rht4 in wheat improvement, we investigated and compared the effects of Rht4 and Rht-B1b on the plant height and yield components using four groups of recombinant inbred lines derived from the cross between “IDO444” (tall, no known dwarfing alleles) and “Rio Blanco” (semi-dwarf, Rht4 + Rht-B1b ) grown under two water regimes. Rht4 , Rht-B1b and Rht4 + Rht-B1b significantly reduced plant height by 11.5%, 19.3% and 18.2%, respectively. There were no additive effects on plant height in Rht4 + Rht-B1b lines. Both Rht4 and Rht-B1b significantly reduced internode length and lodging score with stronger effects by Rht-B1b . Water stress affected the plant height related traits of the single Rht-B1b lines more than that of the Rht4 lines, except for distance from spike to flag leaf ligule. Grain number was increased by Rht4 and Rht-B1b , but higher spike numbers was only observed in lines with Rht-B1b . Both Rht4 and Rht-B1b significantly reduced thousand kernels weight. Rht-B1b reduced above-ground biomass but increased grain yield and harvest index, while Rht4 had less effect on these traits, compared with tall lines under both well-watered and water-stressed conditions. The Rht4 + Rht-B1b lines produced the highest yield under both water regimes, with more grain number, greater spike number and higher harvest index. In conclusion, Rht4 did not show advantages over Rht-B1b on grain yield, but Rht4 + Rht-B1b did, in both water regimes, which suggests that Rht4 should be combined with Rht-B1b in wheat improvement.

A new species, Etlingera frederikii, is described and illustrated, and is the first record of the genus in the Bougainville Region. Etlingera frederikii and E. cevuga, which occurs in Fiji and Samoa, are the two most easterly species in the distribution range of the genus. The new species differs from Etlingera cevuga in its much larger leaves, with a conspicuously silky-haired band on the ligule; the smaller, narrowly ovoid to cylindrical inflorescence with pale brown bracts (not hemiglobose with reddish brown bracts); and fewer, smaller flowers.