Complex but Clear Allopolyploid Pattern of Subtribe Tussilagininae (Asteraceae: Senecioneae) Revealed by Robust Phylogenomic Evidence, with Development of a Novel Homeolog-Sorting Pipeline.

Polyploidy is a significant mechanism in eukaryotic evolution and is particularly prevalent in the plant kingdom. However, our knowledge about this phenomenon and its effects on evolution remains limited. A major obstacle to the study of polyploidy is the great difficulty in untangling the origins of allopolyploids. Due to the drastic genome changes and the erosion of allopolyploidy signals caused by the combined effects of hybridization and complex post-polyploid diploidization processes, resolving the origins of allopolyploids has long been a challenging task. Here we revisit this issue with the interesting case of subtribe Tussilagininae (Asteraceae: Senecioneae) and by developing HomeoSorter, a new pipeline for network inferences by phasing homeologs to parental subgenomes. The pipeline is based on the basic idea of a previous study but with major changes to address the scaling problem and implement some new functions. With simulated data, we demonstrate that HomeoSorter works efficiently on genome-scale data and has high accuracy in identifying polyploid patterns and assigning homeologs. Using HomeoSorter, the maximum pseudo-likelihood model of Phylonet, and genome-scale data, we further address the complex origin of Tussilagininae, a speciose group (ca. 45 genera and 710 species) characterized by having high base chromosome numbers (mainly x = 30, 40). In particular, the inferred patterns are strongly supported by the chromosomal evidence. Tussilagininae is revealed to comprise two large groups with successive allopolyploid origins: Tussilagininae s.s. (mainly x = 30) and the Gynoxyoid group (x = 40). Two allopolyploidy events first give rise to Tussilagininae s.s., with the first event occurring between the ancestor of subtribe Senecioninae (x = 10) and a lineage (highly probably with x = 10) related to the Brachyglottis alliance, and the resulting hybrid lineage crossing with the ancestor of Chersodoma (x = 10) and leading to Tussilagininae s.s. Then, after early diversification, the Central American group (mainly x = 30) of Tussilagininae s.s., is involved in a third allopolyploidy event with, again, the Chersodoma lineage and produces the Gynoxyoid group. Our study highlights the value of HomeoSorter and the homeolog-sorting approach in polyploid phylogenetics. With rich species diversity and clear evolutionary patterns, Tussilagininae s.s. and the Gynoxyoid group are also excellent models for future investigations of polyploidy.

[Rapid identification of Dendrobium plants based on near infrared diffuse reflection spectroscopy].

Near infrared diffuse reflection spectra of 15 species' 171 samples of Dendrobium combined with chemometrics statistical analysis were used to build prediction model, in order to discriminate different species of Dendrobium quickly and nondestructively. Hotelling T2 was applied to stability analysis of spectrum of 5 random drawing samples, and the results showed that the samples spectrum possessed good stability. Orthogonal test L24 (2 x 4 x 3 x 8) was designed to optimize optical path type, spectral band, derivative and smooth. The result of orthogonal test was analyzed by principal component analysis, which revealed that when 6500-4000 cm(-1) spectral band was applied, and with multiplicative scatter correction, second derivative, Norris smooth, and the number of principal components 7, the spectrum distinguishing accuracy was 100%. With the optimized condition of orthogonal test as the input value of partial least squares discriminant analysis and random drawing 123 samples as calibration set to establish the prediction model, and the rest 48 samples as prediction set were use to assess the property of the prediction model, the results indicated that the accumulating contribution rate of the first 3 principal components of the model was 99.36%, the identification of the standard deviation was +/- 0.1, and the correct recognition rate of the model was 97.92%. The results were satisfied. The method provided a new way for the rapid identification of different species of Dendrobium, and also supplied a reference for the authentication of medicinal plants.

Temochloa (Poaceae, Bambusoideae), a newly-recorded bamboo genus for China and Vietnam, with new taxa and a re-interpretation of flowering structures.

Neomicrocalamus and Temochloa are closely-related genera for which 'inflorescence' structures were incompletely understood and difficult to reconcile. After re-examining the inflorescence morphology, the so-called 'spikelets' of both genera as described should instead be recognised as pseudospikelets with mostly inactive axillary buds. The new bamboo taxa, comprising two varieties of a new species, are placed in Temochloa, representing a new genus record for China and Vietnam.

A Novel Elucidation for Synflorescences of Chinese Bamboos.

The objective of this work is to elucidate the flowering structures of Chinese bamboos applying the synflorescence concept. To keep in line with grasses, the bamboo synflorescence is defined as a whole culm or a whole branch terminating in an inflorescence. For the first time, the repetitive and fundamental unit of bamboo synflorescences is clearly identified and termed as the "basic flowering branch". The basic flowering branch could be considered as the most simplified synflorescence for a bamboo species. Applying the synflorescence concept, the pseudospikelet is interpreted as a sort of basic flowering branch rather than a spikelet. Consequently, the synflorescence development pattern is consistent throughout the whole family. This study also marks the first recognition of both pseudospikelets and true spikelet flowering branches within the same bamboo synflorescence, which is observed in the genera Brachystachyum, Semiarundinaria and Menstruocalamus.

The identity of Sasaoblongula C.H.Hu (Poaceae, Bambusoideae, Arundinarieae): evidence from morphology and molecular data.

Sasaoblongula was described in 1987 based on a cultivated plant at the bamboo garden of Sun Yat-sen University. This species has two or three branches at the upper nodes, which differ from the rest of Sasa species that have a single branch per node. During the field trip to Baishi Town, Yunfu City, Guangdong Province in July 2021, one bamboo species with oblong foliage leaves was collected and matches the isotype. Then, our question was to test the identity of S.oblongula concerning other Sasa species based on morphology and molecular data. To do that, we sequenced the whole chloroplast genome of S.oblongula and did a phylogenetic analysis. Our morphological results indicate that the new collection is S.oblongula. The phylogenetic tree showed that S.oblongula is close to Pseudosasa, instead of Sasa species. Therefore, we transferred it to the genus Pseudosasa, and a revised description of P.oblongula is provided here.

Kengiochloa, a new bamboo genus to accommodate the morphologically unique species, Pseudosasapubiflora (Poaceae).

Pseudosasa was confirmed as polyphyletic by recent phylogenetic analyses, with Chinese species of Pseudosasa distantly related to those from Japan. Among the Chinese species of Pseudosasa, Pseudosasapubiflora is a morphologically unique as well as taxonomically problematic species endemic to South China, of which the generic designation is still uncertain. Molecular analyses based on both plastid and nuclear genomic data demonstrated that this species is closest to the recently published genus Sinosasa. Morphologically, the two are somewhat similar to each other in flowering branches developing at the nodes of every order of branches, raceme-like units of inflorescence with 3-5 short spikelets, each spikelet with few florets including a rudimentary one at the apex, and each floret with 3 stamens and 2 stigmas. However, P.pubiflora is very different from Sinosasa species in many reproductive and vegetative characters, such as the morphology of paracladia (lateral spikelet "pedicels"), the absence or existence of pulvinus at the base of paracladia, the relative length of the upper glume and the lowest lemma, the shape of lodicules and primary culm buds, the branch complement, the morphology of nodes, culm leaves and dried foliage leaf blades, and the number of foliage leaves per ultimate branchlet. The morphological and molecular evidence warrants recognition of a new genus to accommodate this unique species, which is here named Kengiochloa. After consulting related literature and examination of herbarium specimens or specimen photos, a taxonomic revision of K.pubiflora and its synonyms was made, and it was confirmed that four names, viz. P.gracilis, Yushanialanshanensis, Arundinariatenuivagina and P.parilis, should be merged with K.pubiflora, while Indocalamuspallidiflorus and Acidosasapaucifolia are distinct species.

Yushaniatomentosa (Poaceae, Bambusoideae), a new combination from Guangxi.

Sasatomentosa is transferred to the genus Yushania following a reassessment based on a new collection with pachymorph and long-necked rhizomes from its type locality in Guangxi, China. Morphologically, it is most similar to Yushaniadoupengshanensis, but differs in culm, branch complement and foliage leaf characters. A revised description of its morphology and color photos are also provided.

Sinosasagracilis (Poaceae, Bambusoideae), a new combination supported by morphological and phylogenetic evidence.

The results of phylogenetic analysis, based on the whole chloroplast genome and morphological study support the transfer of a long ignored bamboo species, Sasagracilis, to the recently established genus, Sinosasa, in this study. Morphologically, this species differs from all the other known Sinosasa species by having very short (2-3 mm) foliage leaf inner ligules, which is unusual in this genus. A revised description of its morphology and colour photos are also provided.

Phylogenomic analyses reveal reticulate evolution between Neomicrocalamus and Temochloa (Poaceae: Bambusoideae).

Neomicrocalamus and Temochloa are closely related to bamboo genera. However, when considered with newly discovered and morphologically similar material from China and Vietnam, the phylogenetic relationship among these three groups was ambiguous in the analyses based on DNA regions. Here, as a means of investigating the relationships among the three bamboo groups and exploring potential sources of genomic conflicts, we present a phylogenomic examination based on the whole plastome, single-nucleotide polymorphism (SNP), and single-copy nuclear (SCN) gene datasets. Three different phylogenetic hypotheses were found. The inconsistency is attributed to the combination of incomplete lineage sorting and introgression. The origin of newly discovered bamboos is from introgressive hybridization between Temochloa liliana (which contributed 80.7% of the genome) and Neomicrocalamus prainii (19.3%), indicating that the newly discovered bamboos are closer to T. liliana in genetics. The more similar morphology and closer distribution elevation also imply a closer relationship between Temochloa and newly discovered bamboos.

Fordiophytontereticaule (Melastomataceae), a new species from China.

A new species, Fordiophytontereticaule, from China, is described and illustrated here based on morphological and molecular evidence. It is morphologically similar to F.faberi in having erect stems, slightly oblique and membranous leaf blades, broadly ovate to suborbicular bracts, and oblong petals, but differs by the terete stems, densely puberulous petioles, and elliptic leaf blades. Our phylogenetic analyses based on plastid genome and nrITS data indicate that this new species is clustered with four Fordiophyton species of Yunnan but placed far apart from F.faberi. An updated key to the genus is also provided.

Chimonobambusasangzhiensis (Poaceae, Bambusoideae), a new combination supported by morphological and molecular evidence.

This study elucidates the taxonomic position of Indosasasangzhiensis in considering whether it belongs to Indosasa or Chimonobambusa. Based on morphological and molecular phylogenetic evidence, our results explicitly indicated that I.sangzhiensis should be a member of Chimonobambusa, rather than Indosasa, and is a distinct species closely related to C.communis, C.opienensis and C.puberula. Thus, the new combination Chimonobambusasangzhiensis (B.M.Yang) N.H.Xia & Z.Y.Niu is made. A detailed description as well as two color plates of this species are also provided.

The floral morphology of four Chinese Bambusa species (Poaceae, Bambusoideae) previously described only from vegetative material.

Due to their specialised flowering biology where frequent or even annual flowering is uncommon, reproductive materials of bamboos are not always available, so hampering taxonomic interpretation and research into other aspects. Bambusacontracta, B.corniculata, B.cornigera and B.subtruncata were established only based on vegetative materials and flowering or fruiting material has been hitherto unknown. The floral morphology of these four species is described for the first time and, correspondingly, epitypes are designated to support a more complete interpretation of the species.

Gelidocalamus fengkaiensis (Poaceae: Bambusoideae), a new bamboo species from Guangdong, China, with an analysis of branch development in relation to flowering.

BACKGROUND: Bamboos, widely distributed in temperate and tropical Asia, Africa and America, refer to a group of special plants in Poaceae, Bambusoideae. China is rich in bamboo species. However, due to a long flowering cycle, the flowering habit and the flowering structure of many bamboo species are still not well understood. Here, we report a new bamboo species from Guangdong, China and an analysis of its interesting branch development in relation to flowering. RESULTS: This species is similar to G. stellatus, the type species, but differs in the characteristics of its lemma and palea, mid-culm branch complement, and culm-sheath ligules. The initial branches at a culm node do not apically develop flowering structures during a flowering episode; instead, these form on what appears to be specialized flowering branches. CONCLUSIONS: The results of morphological comparison support the recognition of Gelidocalamus fengkaiensis as a new species. And during a flowering episode, two branch types ('foliage branch' and 'flowering branch') can be distinguished in this species.

Documentation of plant diversity of Southeast Asia: the new role of Belt and Road Initiative.

Editorial of special issue of plant diversity in southeastern Asia.

Khoonmengia honbaensis, a new genus and species of temperate bamboo (Poaceae, Bambusoideae) from central-southern Vietnam.

A new genus of Arundinarieae, Khoonmengia, is established to accommodate a unique new bamboo species, K. honbaensis, from central-southern Vietnam. The morphological features, habitats and distribution of Khoonmengia and related genera, i.e. Ampelocalamus and Hsuehochloa, are compared. The characters of its scrambling habit, internodes with brownish green dots, conspicuous nodes swollen at one side, elliptic buds wholly sunken into culm, extravaginal branching pattern, mid-culm branch complement with one central dominant branch elongating to reiterate the culm accompanied by several lateral slender branches, swollen culm sheath base with a distinctive zone of transverse wrinkles, synflorescence composed of only one spikelet, single or several to many synflorescences arranged into a raceme or panicle terminal on leafy branches, purple anthers and nut-like caryopsis with hardened pericarp and loosely adherent lemma and palea distinguish K. honbaensis from morphologically similar taxa. In order to investigate the phylogenetic position of this unknown bamboo, molecular phylogenetic analyses based on the nuclear gene GBSSI were also conducted, and the results proved that K. honbaensis is definitely a member of Arundinarieae with an isolated position, which also indicated that this species could not be assigned to any of the already described genera and supported the establishment of the new genus.

Schizostachyum dakrongense (Poaceae, Bambusoideae), a new species from Dakrong Nature Reserve, Vietnam.

Schizostachyum dakrongense is a new species of woody bamboo from Dakrong Nature Reserve, Quang Tri Province, central Vietnam. It is closely related to S. hainanense but differs by its pseudospikelets having terminal rachilla segments with ciliate margin and 6 bracts; culm sheath with the base of the outer margin having a slight projection below its point of attachment at the node, as well as sheath blades usually less than half as long as the culm sheath proper; and leaf blades pale-puberulent and sparsely pilosulous on the abaxial surface. The new species is described and illustrated here.