Temperate Bamboos Research Articles

Overwintering performance of bamboo leaves, and establishment of mathematical model for the distribution and introduction prediction of bamboos.

Bamboo has great economic values and is used extensively in many industries, and their natural distribution range was divided into 12 zones in China according to the temperature of their geographical distribution in previous works. Different bamboo species had significantly different abilities in low-temperature tolerance, which need to be considered carefully during ex-situ introduction. In this paper, we observed and evaluated the low-temperature damage of 19 bamboo species in winter, and measured the physiological changes of bamboo leaves. A total of 3060 leaf samples were obtained from 102 core collections in 34 bamboo species from the 5 regions of Chinese mainland for anatomical comparison, in order to screen out the key anatomical indicators related to their low-temperature tolerance and to establish a mathematical prediction model for bamboo introduction. The results showed that the low-temperature resistance of clustered bamboos was generally lower than that of the scattered bamboos. The decreased temperature led to the constant decrease of net photosynthetic rate and transpiration rate, but the increase of soluble sugar content in all bamboo species. There was no dormancy for all bamboo species in winter. The temperate bamboos showed lower photosynthesis as compared to tropical bamboos in winter. The leaf shape of bamboos was closely related to their distribution. A total of 13 leaf indicators were screened and more suitable to estimate the low-temperature tolerant abilities of bamboos and to predict their distribution. The MNLR (multiple nonlinear regression) mathematical model showed the highest fitting degree and the optimal prediction ability in the potential northernmost introduction range of bamboos. This study lay a foundation for bamboo introduction, and could also reduce the economic losses caused by the wrong introduction.

Hybridization in the Temperate Bamboos (Poaceae: Bambusoideae: Arundinarieae): A Phylogenetic Study Using AFLPs and cpDNA Sequence Data

Abstract—The temperate bamboos are a taxonomically difficult group with nearly 600 species in approximately 30 genera and at least 12 constituent lineages. In this study, phylogenetic relationships were explored using amplified fragment length polymorphism (AFLP) data in comparison with a phylogeny based on plastid DNA sequences, with an emphasis on Arundinaria of North America and its allies in East Asia (the Arundinaria clade). Molecular analyses involved 248 individuals in 10 genera and 60 species. Hybridization was detected both within and among genera. Comparative analyses indicated hybrid origins for species in several widespread and well-known genera, including Hibanobambusa, Sasaella, and Semiarundinaria. Evidence also indicated that Pseudosasa japonica (the type species of Pseudosasa) is an intergeneric hybrid involving Pleioblastus and Sasamorpha. In addition, cryptic hybrids were detected within and among Pleioblastus, Sasa, and Sasamorpha. After accounting for hybrids, phylogenetic analyses of AFLP data provided resolution for core lineages in the Arundinaria clade, including Pleioblastus sensu stricto, Sasa s. s., and Sasamorpha. AFLP data also provided evidence for the monophyly of the North American cane bamboos (Arundinaria, three species) but failed to identify their closest relative among the East Asian taxa. The broader evolutionary implications of hybridization in the temperate bamboos are discussed along with recommendations for future studies.

Chloroplast-based DNA barcode analysis indicates high discriminatory potential of matK locus in Himalayan temperate bamboos

The study was conducted to evaluate the discriminatory potential of selected chloroplast-based DNA barcode regions for identifying and resolving phylogeny of theIndian bamboos. Among 11 chloroplast markers screened, only four, namely matK, rbcL, psbK-I and rps16-trnQ showed successful amplification in 88 genotypes of 30 Indian bamboo taxa under Bambuseae and Arundinarieaetribes. A total of 244 sequences were generated for the four chloroplast regions. Tree-based analysis demonstrated that none of the tested regions successfully discriminated the taxa under Bambuseae tribe. Importantly, our highly concerned Himalayan temperate bamboo species under Arundinarieae tribe, were successfully discriminated by matK locus with high bootstrap support(>60%). Sequence comparisons revealed that the discriminatory power demonstrated by matK region actually lies in the few unique fixed nucleotides (UFNs)despite the overall DNA polymorphism. Although, rps16-trnQ region was found to be the most polymorphic and revealed high genetic divergence among different taxonomic levels, it could not successfully discriminated the taxa with strong statistical support. In ataxonomically difficult plant group like bamboos, whose genome is relatively more complex and has a slow rate of molecular evolution, it is difficult to get a universal marker. Further, highly variable barcode regions utilized in other speciesmay not be informative, and thus, thedevelopment of DNA barcodes for different taxonomic levels, such as lineages or tribes could be a viable approach.

Parallel ddRAD and Genome Skimming Analyses Reveal a Radiative and Reticulate Evolutionary History of the Temperate Bamboos.

Rapid evolutionary radiations are among the most challenging phylogenetic problems, wherein different types of data (e.g., morphology and molecular) or genetic markers (e.g., nuclear and organelle) often yield inconsistent results. The tribe Arundinarieae, that is, the temperate bamboos, is a clade of tetraploid originated 22 Ma and subsequently radiated in East Asia. Previous studies of Arundinarieae have found conflicting relationships and/or low support. Here, we obtain nuclear markers from ddRAD data for 213 Arundinarieae taxa and parallel sampling of chloroplast genomes from genome skimming for 147 taxa. We first assess the feasibility of using ddRAD-seq data for phylogenetic estimates of paleopolyploid and rapidly radiated lineages, optimize clustering thresholds, and analysis workflow for orthology identification. Reference-based ddRAD data assembly approaches perform well and yield strongly supported relationships that are generally concordant with morphology-based taxonomy. We recover five major lineages, two of which are notable (the pachymorph and leptomorph lineages), in that they correspond with distinct rhizome morphologies. By contrast, the phylogeny from chloroplast genomes differed significantly. Based on multiple lines of evidence, the ddRAD tree is favored as the best species tree estimation for temperate bamboos. Using a time-calibrated ddRAD tree, we find that Arundinarieae diversified rapidly around the mid-Miocene corresponding with intensification of the East Asian monsoon and the evolution of key innovations including the leptomorph rhizomes. Our results provide a highly resolved phylogeny of Arundinarieae, shed new light on the radiation and reticulate evolutionary history of this tribe, and provide an empirical example for the study of recalcitrant plant radiations. [Arundinarieae; ddRAD; paleopolyploid; genome skimming; rapid diversification; incongruence.]

Tropical plants evolve faster than their temperate relatives: a case from the bamboos (Poaceae: Bambusoideae) based on chloroplast genome data

The evolutionary speed hypothesis (ESH) states that the molecular evolutionary rates of plants in the warm areas are higher than that in the cool areas. Nevertheless, largely due to the scarcity of molecular data from lower taxonomic lineages, ESH remains elusive in plants. In this study, we comprehensively conducted genome-wide comparative analyses of a total of 76 chloroplast (cp) genomes of the bamboos (Poaceae: Bambusoideae), with 10 of them newly generated, to test the ESH via investigating the potential association between their cp genome evolutionary rate and geographical distribution pattern. The results showed extreme heterogeneity of the evolutionary rate within the bamboos, with the lowest value found in temperate bamboos (tribe Arundinarieae) being approximately 1/4 of that in the tropical ones (tribe Olyreae). All the 91 non-coding loci and 75 coding loci evolve consistently faster in tribe Olyreae than that in tribe Arundinarieae. Most of the non-coding (82 out of 91) and coding (73 out of 75) loci in the tropical woody bamboos (tribe Bambuseae) also evolve faster than those in the temperate woody bamboos (tribe Arundinarieae). Moreover, the split of tropical and temperate bamboos was apparently accompanied with the change of cp genome evolutionary rate. This is by far the first case using cp genome data to support the ESH via showing the tropical plants evolve faster than their closely related temperate ones, and will shed new light on our understanding of ESH and the adaptation of plants.

Phylogenomic analyses reveal intractable evolutionary history of a temperate bamboo genus (Poaceae: Bambusoideae)

Shibataea is a genus of temperate bamboos (Poaceae: Bambusoideae) endemic to China, but little is known about its phylogenetic position and interspecific relationships. To elucidate the phylogenetic relationship of the bamboo genus Shibataea, we performed genome-scale phylogenetic analysis of all seven species and one variety of the genus using double digest restriction-site associated DNA sequencing (ddRAD-seq) and whole plastid genomes generated using genome skimming. Our phylogenomic analyses based on ddRAD-seq and plastome data congruently recovered Shibataea as monophyletic. The nuclear data resolved S. hispida as the earliest diverged species, followed by S. chinensis, while the rest of Shibataea can be further divided into two clades. However, the plastid and nuclear topologies conflict significantly. By comparing the results of network analysis and topologies reconstructed from different datasets, we identify S. kumasasa as the most admixed species, which may be caused by incomplete lineage sorting (ILS) or interspecific gene flow with four sympatric species. This study highlights the power of ddRAD and plastome data in resolving complex relationships in the intractable bamboo genus.

Apparent Tolerance of Low Water Availability in Temperate Asian Bamboos1

Abstract Suitable plant water dynamics and the ability to withstand periods of low moisture input facilitate plant establishment in seasonally arid regions. Temperate bamboos are a major constituent of mixed evergreen and deciduous forests throughout temperate East Asia but play only an incidental role in North American forests and are altogether absent in the Pacific Northwest forest. Many bamboo species are classified as mesic or riparian, but none are considered drought tolerant. To assess their ability to withstand low water, we subjected five Asian temperate and one North American temperate bamboo species to three irrigation treatments: 100%, 50%, and 10% replacement of water lost through evapotranspiration. Plants were irrigated every four days over a 31-day period. Plant response to treatments was measured with stomatal conductance, leaf xylem water potentials, and intrinsic water use efficiency (iWUE). Pleioblastus distichus and Pseudosasa japonica showed significant reductions in conductance between high and low irrigation treatments. Sasa palmata had significantly lower stomatal conductance in all treatments. Pleioblastus chino displayed significantly higher iWUE in the mid irrigation treatment and Arunindaria gigantea displayed significantly lower iWUE than P. chino and S. palmata in the low irrigation treatment. The Asian bamboo species examined here tolerate low water availability and readily acclimate to different soil moisture conditions. Index words: Temperate bamboos, irrigation response, stomatal conductance, intrinsic water use efficiency. Species used in this study: Giant Cane [Arundinaria gigantea (Walt.) Muhl.]; Pleioblastus chino (Franchet & Savatier) Makino; Pleioblastus distichus (Mitford) Nakai; Pseudosasa japonica (Makino); Sasa palmata (Bean) Nakai.

Genome-wide RAD sequencing data provide unprecedented resolution of the phylogeny of temperate bamboos (Poaceae: Bambusoideae)

The temperate bamboos (tribe Arundinarieae, Poaceae) are strongly supported as monophyly in recent molecular studies, but taxonomic delineation and phylogenetic relationships within the tribe lack resolution. Here, we sampled 39 species (36 temperate bamboos and 3 outgroups) for restriction-site associated DNA sequencing (RAD-seq) with an emphasis on Phyllostachys clade and related clades. Using the largest data matrix for the bamboos to date, we were able to infer phylogenetic relationships with unparalleled resolution. The Phyllostachys, Shibataea, and Arundinaria clades defined from plastid phylogeny, were not supported as monophyletic group. However, the RAD-seq phylogeny largely agreed with the morphology-based taxonomy, with two clades having leptomorph rhizomes strongly supported as monophyletic group. We also explored two approaches, BWA-GATK (a mapping system) and Stacks (a grouping system), for differences in SNP calling and phylogeny inference. For the same level of missing data, the BWA-GATK pipeline produced much more SNPs in comparison with Stacks. Phylogenetic analyses of the largest data matrices from both pipelines, using concatenation and coalescent methods provided similar tree topologies, despite the presence of missing data. Our study demonstrates the utility of RAD-seq data for elucidating phylogenetic relationships between genera and higher taxonomic levels in this important but phylogenetically challenging group.

Exploring Bamboo Leaf Nutrient Value in the USNPGS Germplasm Collection

Bamboo shoots and leaves are nutritious, providing food for human and animal consumption. However their nutrient value depends on a number of factors including the bamboo species (e.g. taxon), harvesting season and growing location. Leaf crude protein content, amino acid composition and mineral element concentration were quantified from leaf samples collected from 222 accessions representing two bamboo types (temperate/tropical), two growing seasons (dry/wet) and three locations (PGRCU-Byron, GA; TARSMayaguez, PR; and Govardhan Gardens-Mayaguez, PR). Significant variability in leaf nutrient value was identified among accessions, types, growing locations and harvesting seasons. On average, bamboo leaf tissue contained 12.92% protein with relatively high percentages of leucine (Leu, 8.97%) and proline (Pro, 7.98%) and low percentages of tryptophan (Trp, 1.69%) and histidine (His, 2.01%). Bamboo leaves also contained relatively high concentrations of the macro-mineral elements potassium (K, 12.17mg/g) and calcium (Ca, 5.37mg/g), high concentrations of the micro-mineral elements manganese (Mn, 388.76 μg/g) and iron (Fe, 123.19 μg/g), and low concentrations of boron (B, 7.8 μg/g) and zinc (Zn, 28.56 μg/g). PI 647932 and TARS 182857 contained the highest and lowest protein content (21.69% and 5.78%), respectively. Temperate bamboos contained a significantly higher percentage of protein (13.02%) than tropical bamboos (12.71%). Leaf samples harvested from the dry season contained a significantly higher percentage of protein (13.12%) than leaf samples harvested from the wet season (12.70%). The leaf samples harvested from Govardhan Garden location contained a higher percentage of protein (13.40%) than from Byron (12.65%) and TARS (12.89%) locations. The leaf samples harvested from Govardhan Garden contained a significantly higher iron concentration (151.22 μg/g) than from the other two locations (118.19 μg/g, 111.52 μg/g), whereas the leaf samples collected from Byron contained a significantly higher zinc concentration (36.03 μg/g) than what was observed from the other two locations (27.83 μg/g, 22.11 μg/g). There was no significant difference in iron and zinc concentrations between leaf samples collected from dry or wet seasons. Tropical bamboo leaves contained a higher iron concentration (131.74 μg/g) than temperate bamboo leaves (118.95 μg/g), whereas temperate bamboo leaves contained a significantly higher zinc concentration (29.82 μg/g) than tropical bamboo leaves (26.01 μg/g). The information on the bamboo leaf nutrient value related to bamboo accessions, types, growing location and harvesting season will be very useful for bamboo growers, processors and consumers.

Independent allopolyploidization events preceded speciation in the temperate and tropical woody bamboos.

The objectives of the current study were to investigate the origin of polyploidy in the woody bamboos and examine putative hybrid relationships in one major lineage (the temperate woody bamboos, tribe Arundinarieae). Phylogenetic analyses were based on sequence data from three nuclear loci and 38 species in 27 genera. We identify six ancestral genome donors for contemporary bamboo lineages: temperate woody bamboos (tribe Arundinarieae) contain genomes A and B, tropical woody bamboos (tribe Bambuseae) contain genomes C and D, and herbaceous bamboos (tribe Olyreae) contain genome H; some hexaploid paleotropical bamboos contain genome E in addition to C and D. Molecular data indicate that allopolyploidy arose independently in temperate (AABB) and tropical woody lineages (CCDD and CCDDEE), and speciation occurred subsequent to polyploidization. Moreover, hybridization has played a surprising and recurrent role in bamboo evolution, generating allohexaploid species in the paleotropical clade and intergeneric hybrids among the allotetraploid temperate bamboos. We suggest this complex history of reticulate evolution is at least partially responsible for the taxonomic difficulty associated with the woody bamboos. This newly-resolved phylogenetic framework reflects a major step forward in our understanding of bamboo biodiversity and has important implications for the interpretation of bamboo phylogenomics.

Chloroplast phylogenomic analyses resolve deep-level relationships of an intractable bamboo tribe Arundinarieae (poaceae).

The temperate woody bamboos constitute a distinct tribe Arundinarieae (Poaceae: Bambusoideae) with high species diversity. Estimating phylogenetic relationships among the 11 major lineages of Arundinarieae has been particularly difficult, owing to a possible rapid radiation and the extremely low rate of sequence divergence. Here, we explore the use of chloroplast genome sequencing for phylogenetic inference. We sampled 25 species (22 temperate bamboos and 3 outgroups) for the complete genome representing eight major lineages of Arundinarieae in an attempt to resolve backbone relationships. Phylogenetic analyses of coding versus noncoding sequences, and of different regions of the genome (large single copy and small single copy, and inverted repeat regions) yielded no well-supported contradicting topologies but potential incongruence was found between the coding and noncoding sequences. The use of various data partitioning schemes in analysis of the complete sequences resulted in nearly identical topologies and node support values, although the partitioning schemes were decisively different from each other as to the fit to the data. Our full genomic data set substantially increased resolution along the backbone and provided strong support for most relationships despite the very short internodes and long branches in the tree. The inferred relationships were also robust to potential confounding factors (e.g., long-branch attraction) and received support from independent indels in the genome. We then added taxa from the three Arundinarieae lineages that were not included in the full-genome data set; each of these were sampled for more than 50% genome sequences. The resulting trees not only corroborated the reconstructed deep-level relationships but also largely resolved the phylogenetic placements of these three additional lineages. Furthermore, adding 129 additional taxa sampled for only eight chloroplast loci to the combined data set yielded almost identical relationships, albeit with low support values. We believe that the inferred phylogeny is robust to taxon sampling. Having resolved the deep-level relationships of Arundinarieae, we illuminate how chloroplast phylogenomics can be used for elucidating difficult phylogeny at low taxonomic levels in intractable plant groups.

Identification of SNP markers for inferring phylogeny in temperate bamboos (Poaceae: Bambusoideae) using RAD sequencing

Phylogenetic relationships among temperate species of bamboo are difficult to resolve, owing to both the challenge of detecting sufficiently variable markers and their polyploid history. Here, we use restriction site-associated DNA sequencing to identify candidate loci with fixed allelic differences segregating between and within two temperate species of bamboos: Arundinaria faberi and Yushania brevipaniculata. Approximately 27 million paired-end sequencing reads were generated across four samples. From pooled data, we assembled 67685 and 70668 de novo contigs from partial overlap among paired-end reads, with an average length of 240 and 241bp for the two species, respectively, which were used to investigate functional classification of RAD tags in a blastx search. Analysed separately by population, we recovered 29443 putatively orthologous RAD tags shared across the four sampled populations, containing 28023 sequence variants, of which c. 13000 are segregating between species, and c. 3000 segregating between populations within each species. Analyses based on these RAD tags yielded robust phylogenetic inferences, even with data set constructed from surprisingly few loci. This study illustrates the potential for reduced-representation genome data to resolve difficult phylogenetic relationships in temperate bamboos.

Shade tolerance of temperate Asian bamboos: a harbinger of their naturalization in Pacific Northwest coniferous forests?

Bamboos native to temperate East Asian coniferous forests arrive with increasing frequency in the United States as horticultural imports, and some are becoming naturalized locally. Given the strong floristic and physiognomic similarities between East Asian and western North American coniferous forests, we asked whether these introduced bamboos could tolerate the varied light regimes within coniferous forests in their new range. Seven temperate Asian bamboos and one North American bamboo (Arundinaria gigantea) were grown within shade structures in an experimental garden; these structures reduced ambient light to three light levels (50, 70, 90 % shade) that occur routinely within coniferous forests in the Pacific Northwest. Species’ responses under these light levels were measured by their light response curves to photosynthesis, resource allocation to light or carbon harvesting centers inferred by CO2 response curves, and shifts amongst forms of leaf Chlorophyll. Bashania fargesii has lower chlorophyll content and photosynthetic rates under high shade (90 %) relative to other Asian species and to B. fargesii grown in 50 and 70 % shade. Bashania fargesii, Sasa kurilensis and A. gigantea also displayed lower photosynthetic rates under 90 % shade compared to plants grown in 50 and 70 % shade and lower electron transport capacity under 70 and 90 % shade compared to plants grown in 50 % shade. In contrast, Pleioblastus chino, Pleioblastus distichus, Pseudosasa japonica, Sasa palmata and Sasaella ramosa display strong tolerance of low light. Our results indicate these five Asian bamboos (and others yet to be introduced) could skirt a major environmental barrier to new species establishment in these North American forests. Measuring a species’ light response curve offers a reliable, rapid means to assess an immigrant species’ potential to tolerate forests’ varied light regimes.

Large multi-locus plastid phylogeny of the tribe Arundinarieae (Poaceae: Bambusoideae) reveals ten major lineages and low rate of molecular divergence

The temperate bamboos (tribe Arundinarieae) are notorious for being taxonomically extremely difficult. China contains some of the world’s greatest diversity of the tribe Arundinarieae, with most genera and species endemic. Previous investigation into phylogenetic relationships of the temperate bamboos revealed several major clades, but emphasis on the species-level relationships among taxa in North America and Japan. To further elucidate relationships among the temperate bamboos, a very broad sampling of Chinese representatives was examined. We produced 9463 bp of sequences from eight non-coding chloroplast regions for 146 species in 26 genera and 5 outgroups. The loci sequenced were atpI/H, psaA-ORF170, rpl32- trnL, rpoB- trnC, rps16- trnQ, trnD/T, trnS/G, and trnT/L. Phylogenetic analyses using maximum parsimony and Bayesian inference supported the monophyly of Arundinarieae. The two major subtribes, Arundinariinae and Shibataeinae, defined on the basis of different synflorescence types, were indicated to be polyphyletic. Most genera in this tribe were confirmed to be paraphyletic or polyphyletic. The cladograms suggest that Arundinarieae is divided into ten major lineages. In addition to six lineages suggested in a previous molecular study (Bergbamboes, the African alpine bamboos, Chimonocalamus, the Shibataea clade, the Phyllostachys clade, and the Arundinaria clade), four additional lineages were recovered in our results, each represented by a single species: Gaoligongshania megalothyrsa, Indocalamus sinicus, Indocalamus wilsonii, Thamnocalamus spathiflorus. Our analyses also indicate that (1) even more than 9000 bp of fast-evolving plastid sequence data cannot resolve the inter- and infra-relationships among and within the ten lineages of the tribe Arundinarieae; (2) an extensive sampling is indispensable for phylogeny reconstruction in this tribe, especially given that many genera appear to be paraphyletic or polyphyletic. Perhaps the ideal way to further illuminate relationships among the temperate bamboos is to sample multiple nuclear loci or whole chloroplast sequences in order to obtain sufficient variation.

Phylogenetic relationships and natural hybridization among the North American woody bamboos (Poaceae: Bambusoideae:Arundinaria)

In spite of the ecological and economic importance of temperate bamboos, relatively little is known about their population biology or evolutionary history. Recently, hybridization has emerged as a potential source of diversity in this group, as well as an underlying cause of taxonomic problems. As part of a broader phylogenetic study of the temperate bamboos, we report the results of an analysis of the North American Arundinaria gigantea species complex, including estimates of genetic variation and molecular evidence of natural hybridization among A. gigantea, A. tecta, and A. appalachiana. The study involved a comparative analysis of amplified fragment length polymorphisms (AFLPs) and chloroplast DNA sequences representing diversity within and among all three species plus individuals with intermediate or unusual morphological characteristics (putative hybrids). Molecular results support the recognition of three species previously defined on the basis of morphology, anatomy, and ecology, with most of the molecular variance accounted for by among-species variation. Molecular evidence also demonstrates that A. tecta and A. appalachiana are sister species, forming a clade that is significantly divergent from A. gigantea. The role of hybridization in the phylogenetic history of Arundinaria is discussed along with implications for the evolution and taxonomy of the temperate woody bamboos.

Phylogeny of the Temperate Bamboos (Poaceae: Bambusoideae: Bambuseae) with an Emphasis on Arundinaria and Allies

The temperate bamboos are a morphologically diverse grass lineage with a complex and problematic taxonomy. We present the first robust multilocus chloroplast phylogeny of the temperate bamboos, assess relationships among key genera with an emphasis on Arundinaria and its allies, and highlight the potential role of hybridization and reticulate evolution in this group. Utilizing a total of twelve plastid DNA regions (1 gene, 10 intergenic spacers, and 1 intron), the temperate clade was resolved to include six major lineages: Bergbamboes, the African alpine bamboos, Chimonocalamus, the Shibataea clade, the Phyllostachys clade, and the Arundinaria clade. Internal resolution varied among these six, in part reflecting sampling density and in part due to apparent evolutionary rate heterogeneity. The recovered phylogeny is largely incongruent with morphological classifications, rendering subtribes and many genera paraphyletic or polyphyletic. Some associations are consistent with existing hypotheses of intergeneric hybridization, while others may indicate convergent evolution, lineage sorting, or previously unsuspected cases of hybridization. Several robust lineages were identified within the Arundinaria clade, including the Medake subclade (Pleioblastus s. s. and allies), Sasa s. s., and the Sinicae subclade (comprising a subset of Chinese taxa currently classified in Acidosasa, Indosasa, Pleioblastus sect. Amari, and Pseudosasa subg. Sinicae). Our analyses also recovered a monophyletic Arundinaria s. s. in North America, and revealed substantial divergence between A. gigantea and A. tecta.

Initial efficiency of a bamboo grove–based treatment system for winery wastewater

The contamination of the water resource is a critical environmental issue. PHYTOREM®, a French company specialized in phytoremediation, has patented an innovative technology using temperate bamboos to treat wastewater. The latter is evenly spread over a bamboo grove and supplies water and nutrients for plant growth. The bamboo grove produces new culms each year and mature culms can be harvested and processed in wood or energy industries. The present experiment demonstrates the contaminant removal efficiency of a bamboo grove composed of three bamboo species. During 2 years winery wastewater was spread over a bamboo plot. Nutrient status of leachate was evaluated, and the results from the treatment plot did not show any difference compared to the control. This experiment showed that 99% of the organic matter and 98% of the nutrients were removed by the soil–bamboo system.

Use of flowering gene FLOWERING LOCUS T (FT) homologs in the phylogenetic analysis of bambusoid and early diverging grasses

A nuclear gene, FLOWERING LOCUS T (FT) homolog, was cloned from Phyllostachys meyeri as PmFT. Its putative copy number was estimated as four by Southern blot analysis, and the two copies were completely sequenced. Twenty-seven FT homolog sequences of bambusoid and early diverging grasses comprised 172-bp exons, and 357- to 785-bp introns exhibited 0-58.9% pairwise divergence with six modal levels. Parsimony analyses of the FT homologs rooted at Pharus virescens produced six equally parsimonious trees. In the strict consensus tree, five clades were resolved; they were affected by divergence of the intron region rather than exon region. The basal clade was Puelioideae, followed by Olyreae clade including Oryza sativa. Streptogyneae clade combined the Olyreae clade with terminal sister clades of the Bambuseae, i.e., pantropical bamboos and East Asiatic temperate bamboos. The global topology suggested that FT homologs are significant for resolving the tribe level. However, the phylogeny of FT homologs does not resolve monophyly in Bambusoideae because of intercalary positioning by Streptogyneae clade. We discussed the role of FT homologs in controlling the inflorescence architecture and position of Streptogyneae in the bamboo phylogeny.

Highly heterogeneous generic delimitation within the temperate bamboo clade (Poaceae: Bambusoideae): evidence from GBSSI and ITS sequences

AbstractThere is much debate about the phylogenetic relationships within the temperate bamboo clade inferred from morphological and anatomical data. To investigate these relationships, internal transcribed spacer (ITS) and partial granule‐bound starch synthase I gene (GBSSI) sequences were obtained from 47 species representing the two widely accepted subtribes and 26 genera of the temperate bamboo clade. All analyses of the DNA data using maximum parsimony and Bayesian reference confirm that the temperate bamboos form a robust monophyly with 100% bootstrap support. Our results suggest that the Racemobambosinae is not a member of the temperate clade. The two major subtribes, Arundinariinae and Shibataeinae, are each rejected as monophyletic. This is somewhat unexpected as the definition of the subtribes is based on the inflorescence types that have been widely accepted. Our results also suggest that, in the temperate clade, Arundinaria s.l., Pleioblastus, Chimonobambusa, Sinobambusa, and even the “well‐defined” Phyllostachys, are not monophyletic. Therefore, most genera, as currently delimited, within the temperate clade are highly heterogeneous. Using GBSSI, ITS, and GBSSI‐ITS combined data it is revealed that Phyllostachys and Shibataea are closely related and that the combination of Menstruocalamus and Qiongzhuea and even some species of Sinobambusa into Chimonobambusa is warranted. Brachystachyum is not supported as being derived within Semiarundinaria. This implies that many morphological characters used for subtribal divisions and generic delimitation in the current systems of bamboo classification are homoplastic and that their evolutionary meaning should be reevaluated.

The gardener's guide to growing temperate bamboos

The gardener's guide to growing temperate bamboos