Bamboo Flowering Research Articles

The presence of the marsupial Dromiciops gliroides in Parque Nacional Los Alerces, Chubut, Southern Argentina, after the synchronous maturation and flowering of native bamboo and subsequent rodent irruption

Dromiciops gliroides is a small nocturnal marsupial found in the temperate forests of Southern Chile and Argentina. It is the only living member of the order Microbiotheria. Here, we describe the discovery and first account of live trapping of D. gliroides in Parque Nacional Los Alerces (Los Alerces National Park) in the province of Chubut, Argentina. This account extends the distribution of this cryptic species south to Parque Nacional Los Alerces (PNLA). The study provides a description of the habitat they were captured in after a recent bamboo flowering and seeding event and subsequent rodent irruption, the first in 70 years in PNLA. Four adult D. gliroides were captured during the study period, and both adult females captured had pouch young present, suggesting birth occurred in late October or early November. Habitat surveys revealed D. gliroides inhabited Nothofagus forest. A lack of fruiting plants in PNLA during the trapping period (spring) suggests their diet is likely restricted to insects at this time. No dreys were detected during habitat surveys, and hence, it is likely D. gliroides utilises tree hollows as refuges and nesting sites in PNLA. Significant threats to the population in PNLA were identified including introduced predators and human-related impacts due to farming and tourism. There is a breeding population of D. gliroides present in Parque Nacional Los Alerces. The newly discovered population now represents the most southern location for D. gliroides in Argentina.

Molecular characterization of FLOWERING LOCUS T(FT)genes from bamboo (Phyllostachys violascens)

Bamboos are versatile multipurpose forest products that are so important economically that they are often referred to as “green gold”. With the development of modern gardens, bamboos have become one of the main garden plants because of their unique aesthetic beauty. However, flowering usually causes bamboo to die. To explore the genetic and molecular mechanisms that underlie the transition from the vegetative to reproductive stage in bamboos, two FT-like genes, PvFT1 and PvFT2, were identified in a bamboo species (Phyllostachys violascens). The cDNA sequences of PvFT1 and PvFT2 consisted of 962 bp and 890 bp, respectively, and each encodes 178 amino acids. These two proteins belonged to the PEBP family and contained a Tyr residue that is critical to differentiate FT and TFL1. Like other florigen, PvFT1 is expressed only in the leaves and reached its highest level 20 to 30 days before flowering. It’s transcript is not detected in those plants that never flowered, while PvFT2 mRNA is observed only in spikelet. PvFT1 transcript accumulation was diurnally expressed with a peak at dusk. Constitutive expression of full-length PvFT1 in rice cause early flowering relative to wild-type and in vitro, 50 % of shooting plants displayed structures that resembled floral organs. Our results suggested that PvFT1 might be a candidate gene for florigen and played a role in the induction of bamboo flowering, while PvFT2 might be involved in the development of floral organs. This information could lead to a better understanding of the mechanisms involved in bamboo flowering.

Identification and characterization of microRNAs at different flowering developmental stages in moso bamboo (Phyllostachys edulis) by high-throughput sequencing.

Researching moso bamboo flowering has been difficult because of its unknown flowering interval and the rarity of florescent samples. To identify microRNAs (miRNAs) and study their expression patterns during the flower developmental process of moso bamboo, small RNAs from non-flowering leaves and four flower developmental periods were sequenced using Illumina technology. In total, 409 known miRNAs and 492 differentially expressed novel miRNAs were identified in moso bamboo. Of the known miRNAs that were differentially expressed between non-flowering and flowering samples, 64 were predicted to have a total of 308 targets. Among the miRNAs, seven known and five novel miRNAs were selected, as were four of their target genes, and their expression profiles were validated using qRT-PCR. The results indicated that the miRNA expression levels were negatively correlated with those of their targets. The research comprehensively revealed that the differentially expressed miRNAs and their targets participated in diverse biological pathways and played significant regulatory roles in moso bamboo flowering. The data provide a significant resource for understanding the molecular mechanisms in moso bamboo flowering and senescence, and serve as the primary foundation for further studies on metabolic regulatory networks that involve miRNAs.

Isolation and characterization of an Indeterminate1 gene, BmID1, from bamboo (Bambusa multiplex)

The ID1 gene regulates a leaf-generated signal required for the transition to flowering in maize. Like ID1, the OsID1 gene acts as a master switch for the transition from the vegetative to the reproductive phase in rice. In this study, an ID1 ortholog, BmID1, was isolated from Bambusa multiplex. The ORF of BmID1 was 1182-bp long, and encoded a peptide of 393 amino acids containing a putative NLS, four zinc finger motifs, and a conserved TRDFLG motif at the C terminal. BmID1 shared 64.9 % identity with the ID1 ortholog in Zea mays and 62.16 % with the ID1 ortholog in Oryza sativa. BmID1 was expressed very weakly in the developing leaves and shoots of flowering plants, but not in those of non-flowering plants. Unlike OsID1, BmID1 was expressed with a circadian rhythm. The BmID1 protein localized to the nucleus, suggesting that it might act as a transcription factor to regulate flowering in bamboo.

Extended flowering intervals of bamboos evolved by discrete multiplication.

Numerous bamboo species collectively flower and seed at dramatically extended, regular intervals - some as long as 120 years. These collective seed releases, termed 'masts', are thought to be a strategy to overwhelm seed predators or to maximise pollination rates. But why are the intervals so long, and how did they evolve? We propose a simple mathematical model that supports their evolution as a two-step process: First, an initial phase in which a mostly annually flowering population synchronises onto a small multi-year interval. Second, a phase of successive small multiplications of the initial synchronisation interval, resulting in the extraordinary intervals seen today. A prediction of the hypothesis is that mast intervals observed today should factorise into small prime numbers. Using a historical data set of bamboo flowering observations, we find strong evidence in favour of this prediction. Our hypothesis provides the first theoretical explanation for the mechanism underlying this remarkable phenomenon.

Fire occurrence in relation to bamboo dominance in the Qinling Mountains of China: Evidence from phytolith and charcoal records in Holocene sediments

The internal genetic clock of semelparous mast-flowering bamboo species creates gregarious regions of flowering and death, thus leading to fuel-load accumulation that potentially promotes fire (Fire-Cycle Hypothesis). Higher abundance of bamboo could be expected to provide greater fuel loads after flowering. Here, we investigated the possible link between bamboo dominance and fire occurrence. As the main food source for the giant panda in the Qinling Mountains of China, Bashania fargesii (Farges Canebrake) and Fargesia qinlingensis (Arrow Bamboo) dominate lower (1000–1900 m) and higher elevations (1800–2700 m), respectively. Four soil profiles (elevation ranging from 1240 to 2170 m) in areas of known recent bamboo flowering events (∼1980) and adjacent non-flowering sites were assessed for phytoliths and charcoal. Characteristic phytoliths were chosen to describe bamboo dynamics, and charcoal particles were extracted from the soil to reconstruct fire history. Carbon 14 dating of soil charcoal samples was conducted using an accelerator mass spectrometry technique. In addition, we chose two depths (28–52 and 90–100 cm) in one Bashania profile (B. fargesii forest) and one Fargesia profile (F. qinlingensis forest) for phytolith dating. Our findings indicate that bamboo has been a dominant component of these ecosystems almost for the entire profile; some 6400 yrs for Bashania and ca. 10000 yrs for the Fargesia. It is also clear from the charcoal and phytolith data that bamboo abundance and recent mast flowering were significantly related to fire occurrence for lower elevation Bashania while the higher elevation Fargesia was not. One of the four profiles had chronological charcoal records throughout and the oldest charcoal aged was ∼1410 yr BP, suggesting an anthropogenic origin. The mixing of phytolith and charcoal made it unrealistic to describe temporal dynamics of bamboo and fire events, and thus our interpretation is cognizant of the dating discrepancies and conservative (less-speculative). Due to the long history of bamboo and much shorter history of fire within the profile, our data lend little evidence to the Fire-Cycle Hypothesis.

Bamboo Resources in Ethiopia: Their value chain and contribution to livelihoods

Ethiopia has an estimated one million hectares of natural bamboo forest, the largest in the African continent. Despite the versatile resource base and advanced bamboo utilization at a global scale, its great potential to enhance socio-economic and ecological development remains unrealized in Ethiopia. More importantly, recent observations in the country showed massive bamboo flowering followed by a death that urges management interventions. The objective of this study was to examine the socio-economic contribution of bamboo resources and typify their marketing value chain across major bamboo-growing and -marketing regions in Ethiopia, in order to promote its sustainable management. Structured questionnaires were administered to a total of 345 households to inspect the relative contribution of bamboo income to household economy. Participatory rural appraisal, key informant interviews, group discussions, market assessment, and field observations were made to understand the bamboo marketing system, actors involved, price trends, and factors affecting the bamboo value chain. Results show that crop and livestock production, forest management, and off-farm activities are major sources of income for respondent households. Fifty-three percent of the respondents reported bamboo income. Though it significantly varies across the study localities (p < 0.005), bamboo income contributed up to 11% of the annual cash income of the households, the lowest (3.4%) at Masha and the largest (38%) at Banja and Bahir Dar Zuria Districts. Positive and significant correlation was observed among cash incomes from bamboo, crop, petty trade, and other Non-Timber Forest Products (NTFPs). Producer farmers, village level traders, town and city wholesalers, small- and medium-scale bamboo processing and marketing firms, and town and city consumers are identified as major actors in the bamboo value chain. Fifty-five percent of the respondents indicated presence of poor horizontal and vertical linkage among actors. Access to market is difficult for a majority (88%) of the producers, and hence they sell bamboo culms and other product forms locally, mainly in roadside markets. Despite the inefficient value chains, 85% of the respondents indicated an increasing trend of demand for bamboo products. Market assessment for bamboo culms showed a price elasticity of demand, which is the change in quantity divided by change in price, up to 1.21 in 2008/2009 and 1.47 in 2009/2010. Nevertheless, bamboo utilization in Ethiopia is basically rudimentary, and bamboo product import exceeds export, in contrast to the resource base of the country. It is also noteworthy that the resource base is declining alarmingly in spite of the little interventions in place. An important policy and development lesson include enhancing further research for technology innovation, upgrading and integrating the bamboo value chain, and promoting sustainable management of the resource base.

Investigating the MicroRNAomes of Two Developmental Phases of Dendrocalamus latiflorus (Poaceae: Bambusoideae) Inflorescences

Plant microRNAs (miRNAs) play important roles in various developmental and physiological processes (e.g. seed germination, vegetative growth, flowering, seed production, and responses to abiotic or biotic stimuli) by targeting mRNAs for cleavage or translational repression at the post-transcriptional level. Bamboo flowering is an unusual physiological phenomenon relative to the typical graminaceous plants. In this study, we focused on the microRNAome of developing Dendrocalamus latiflorus inflorescences. Solexa high-throughput small RNA (sRNA) sequencing technology was used to sequence and quantify the miRNAs expressed during two phases of D. latiflorus flower development. A total of 118 conserved miRNAs and 47 novel miRNAs was identified in the developing flowers. The transcript levels of most of the miRNAs were similar between the two phases. However, five miRNAs showed distinct changes as the flowering developed, with the novel miRNA dla-miR18 in particular showing a large difference in transcript abundance between the two phases. Fifteen of the D. latiflorus miRNAs found in this study appeared likely to be specific to flower development. Moreover, 130 of the floral unigenes of D. latiflorus were determined to be putative targets of the miRNAs, and the miRNA cleavage sites of seven of these putative targets were validated by 5′-RACE. The results of this study provide the first broad survey of the microRNAomes of Bambusoideae and yield valuable insights into the potential roles of microRNAs in bamboo inflorescence development. Our findings represent a starting point for future functional research on the role of miRNA in the flower development in D. latiflorus and related species.

Giant Pandas Are Not an Evolutionary cul-de-sac: Evidence from Multidisciplinary Research

The giant panda (Ailuropoda melanoleuca) is one of the world's most endangered mammals and remains threatened by environmental and anthropogenic pressure. It is commonly argued that giant pandas are an evolutionary cul-de-sac because of their specialized bamboo diet, phylogenetic changes in body size, small population, low genetic diversity, and low reproductive rate. This notion is incorrect, arose from a poor understanding or appreciation of giant panda biology, and is in need of correction. In this review, we summarize research across morphology, ecology, and genetics to dispel the idea, once and for all, that giant pandas are evolutionary dead-end. The latest and most advanced research shows that giant pandas are successful animals highly adapted to a specialized bamboo diet via morphological, ecological, and genetic adaptations and coadaptation of gut microbiota. We also debunk misconceptions around population size, population growth rate, and genetic variation. During their evolutionary history spanning 8 My, giant pandas have survived diet specialization, massive bamboo flowering and die off, and rapid climate oscillations. Now, they are suffering from enormous human interference. Fortunately, continued conservation effort is greatly reducing impacts from anthropogenic interference and allowing giant panda populations and habitat to recover. Previous ideas of a giant panda evolutionary cul-de-sac resulted from an unsystematic and unsophisticated understanding of their biology and it is time to shed this baggage and focus on the survival and maintenance of this high-profile species.

Rodent outbreak in relation to bamboo flowering in north-eastern region of India

Rodent outbreaks have been recorded in the north-eastern hill region of India since time immemorial. This study was carried out in Arunachal Pradesh where rodent outbreaks are associated with Dendrocalamus hamiltonii, Dendrocalamus strictus, Bambusa tulda, Bambusa balcoa and Schizostachyum arunachalensis. Four species of rodents are reported in the flowering area of which Rattus rattus is predominant and causes greatest damage to many crops. The greatest damage recorded in rice ranged from 12.9% to 15.4% in the bamboo flowering year, whereas it was 5.3% to 5.8% in the non-flowering year. Higher levels of damage were also observed in maize, pineapple, cabbage, French bean, potato, tomato and tapioca in bamboo flowering affected area than in other areas. Live burrows count, trap index and percent damage revealed that in bamboo flowering areas, the rodent population was significantly increased. The comparison of nutrient content of bamboo seeds and other food materials suggested that higher carbohydrate content of the bamboo seeds triggered the active behaviour of rodents. Damage was caused only to those crops which are a very good source of carbohydrate. The cumulative effects of rainfall, flowering season, hunting of predatory animals or birds and geographical barriers might be responsible for the outbreak of rodents. The study also explains why every flowering season does not result in a rodent outbreak of the same severity.

Population dynamics of rodents during bamboo flowering event in North East India

The ecological aspects of rodents during bamboo flowering (BF) phase (Mautam) were studied in Meghalaya and Mizoram states of India during 2005-2008. Rodent population was almost stable during BF in Meghalaya. Likewise, it was also normal in Mizoram during 2005 to 2007. However, rodent outbreak was observed after gregarious flowering (GF) of M. baccifera during 2007-08 in Mizoram and it was more severe after complete fruit shedding. Rodent activities were found to be highest during July to October and their population was significantly higher in upland cultivated areas especially near animal farm-houses. Out of 12 species recorded, merely six species of rodents were observed in BF areas of Mizoram. Surprisingly, Bandicota bengalensis was recorded to be a pre-dominant species, though not observed in bamboo forests. Species wise, sex ratio of rodents varied from 1:0.81 to 1:1.12 in Mizoram. Furthermore, rodent population was recorded to be higher in GF areas and location wise it was more in Kolasib district of Mizoram. In general, sex ratio of rodents was quite equal in all districts of Mizoram; however it was basically female biased in sporadic flowering (SF) areas. Maturity status of rodents in Mizoram indicated their complete adulthood during flowering time; where testes and vaginas were largely scrotal and perforated type, respectively. Overall study concludes that, bamboo flowering alone didn’t increase rodent population significantly; but other factors mainly weather and starting time of flowering could also be involved in this complex process.

Characterization of the floral transcriptome of Moso bamboo (Phyllostachys edulis) at different flowering developmental stages by transcriptome sequencing and RNA-seq analysis.

BackgroundAs an arborescent and perennial plant, Moso bamboo (Phyllostachys edulis (Carrière) J. Houzeau, synonym Phyllostachys heterocycla Carrière) is characterized by its infrequent sexual reproduction with flowering intervals ranging from several to more than a hundred years. However, little bamboo genomic research has been conducted on this due to a variety of reasons. Here, for the first time, we investigated the transcriptome of developing flowers in Moso bamboo by using high-throughput Illumina GAII sequencing and mapping short reads to the Moso bamboo genome and reference genes. We performed RNA-seq analysis on four important stages of flower development, and obtained extensive gene and transcript abundance data for the floral transcriptome of this key bamboo species.ResultsWe constructed a cDNA library using equal amounts of RNA from Moso bamboo leaf samples from non-flowering plants (CK) and mixed flower samples (F) of four flower development stages. We generated more than 67 million reads from each of the CK and F samples. About 70% of the reads could be uniquely mapped to the Moso bamboo genome and the reference genes. Genes detected at each stage were categorized to putative functional categories based on their expression patterns. The analysis of RNA-seq data of bamboo flowering tissues at different developmental stages reveals key gene expression properties during the flower development of bamboo.ConclusionWe showed that a combination of transcriptome sequencing and RNA-seq analysis was a powerful approach to identifying candidate genes related to floral transition and flower development in bamboo species. The results give a better insight into the mechanisms of Moso bamboo flowering and ageing. This transcriptomic data also provides an important gene resource for improving breeding for Moso bamboo.

Flower and seed production in a series of flowerings from sporadic events before to after mass flowering of the dwarf bamboo Sasa veitchii var. hirsuta

The aim of this study was to determine seed production patterns in a series of flowerings from sporadic events before to after mass flowering and to clarify the relationship between the occurrence of second flowering and seed production in the first flowering of mass-flowering events for S. veitchii var. hirsuta. The results revealed that ratios of numbers of seeds to florets per inflorescence in the first and second flowerings of a mass-flowering event were as large as those in the first flowering of a sporadic-flowering event before mass flowering, and were larger than those in the second flowering of a sporadic-flowering event before mass flowering and in both flowerings of a sporadic-flowering event after mass flowering. However, estimated number of produced seeds per square meter in mass flowering was higher than that in sporadic flowering before it. This suggests that seed production is promoted in mass flowering, and that sporadic flowering beforehand can potentially contribute to successful regeneration. At a site where seeds were produced in the first flowering of a mass-flowering event, flower production and the seed germination ratio were smaller in the second flowering. Conversely, at a site where few seeds were produced in the first flowering of a mass-flowering event, there was no significant difference in flower production between the first and second flowerings, and the seed germination ratio in the second flowering was more than 40 %. This suggests that the second flowering of a mass-flowering event is related to seed production in the first flowering.

Genetic Diversity and Age Class Structure of Seedlings and Saplings after a Mast Flowering of Bamboo in the Brazilian Atlantic Forest

Premise of research. Aulonemia aristulata (Döll) McClure—an endemic Brazilian species—flowers, sets seed, and subsequently dies after many years of vegetative growth. After it has died, plants regenerate by seed germination on the forest floor. Because of the sporadic and unusual records of the flowering cycle and the difficulty of identifying individuals, few studies of the genetic structure of bamboo populations have been published. In this study, we investigated how the flowering event affects the genetic diversity among different populations and evaluated the genetic variability between two ontogenic stages.Methodology. We collected seedlings in July 2009 and saplings in February 2010 in two study areas. We investigated the genetic diversity using markers with different modes of inheritance: nuclear simple sequence repeats (SSRs) and chloroplast SSRs.Pivotal results. The nuclear genetic diversity of the study populations was higher than in other bamboo species. All populations had high and significant inbreeding values, indicating a deficiency of heterozygotes. In general, saplings exhibited less inbreeding than seedlings. Moreover, chloroplast genetic diversity was low, which may indicate that individuals share maternal ancestors.Conclusions. This study demonstrates that sexual reproduction, demographic history, and colonization patterns may contribute to population diversity. The decrease in plant density between ontogenetic stages (i.e., from seedling to sapling) was associated with a higher frequency of homozygotes in seedlings compared with saplings and could indicate intraspecific competition coupled with inbreeding depression as the main factor reducing plant density in bamboos.

The Characteristics of Bamboo Germplasm Resources and its Conservation from Yunnan, China

The germplasm resources of bamboos is very rich in Yunnan. Though the reaserch of bamboo diversity conservation is just beginning today, the insitu conservation, developing nature reserve, and exsitu conservation, setting up bamboos garden, have got a great achievement. The period of bamboo flowering is longer and the fruitification rate is lower, so the Collestion of seeds is difficulty. The flowering, fruitting of some bamboos and its seeds collectiong, storage and utilization are introduced in this paper.

Correlation between DNA methylation and chronological age of Moso bamboo (Phyllostachys heterocycla var. pubescens).

BackgroundChronological age is the primary consideration when studying the physiological development, aging, and flowering of bamboo. However, it’s difficult to determine bamboo’s chronological age if the time of germination is unknown. To investigate the chronological age of bamboo from the genomic DNA methylation profile, methylation-sensitive amplification polymorphism (MSAP) was employed to analyze the genomic DNA methylation of Moso bamboo (Phyllostachys heterocycla var. pubescens) from stands of nine germination-ages, using six primer pairs which have previously been shown to yield methylation rates that reflect the age of Moso bamboo.ResultsThe results showed that the total genomic DNA methylation rates in Moso bamboo at different chronological ages were significantly different, and the increase in genomic DNA methylation rate was consistent with the increase of chronological age. Six primer pairs displayed different genomic DNA methylation rates in Moso bamboo of nine age’s group; however, a significantly positive correlation existed among these primer pairs. An integrated index was obtained by performing principal component analysis on the six primer pairs to represent the genomic DNA methylation levels in Moso bamboo of various chronological ages, and a quadratic curve between the chronological age and genomic DNA methylation levels was obtained.ConclusionsSuch a relationship between DNA methylation and its chronological age may serve a reference for its aging study in Moso bamboo.Electronic supplementary materialThe online version of this article (doi:10.1186/1999-3110-55-4) contains supplementary material, which is available to authorized users.

An Effective Protocol for Micropropagation of Edible Bamboo Species (Bambusa tuldaandMelocanna baccifera) through Nodal Culture

High demand for edible bamboo shoots of Bambusa tulda and Melocanna baccifera in many Asian ethnic groups has led to the need for developing intensive bamboo farming. To achieve this, in vitro regeneration of bamboo plantlets is needed due to the long and irregular bamboo flowering cycle and scarcity of bamboo seeds. An effective protocol for plantlets regeneration in B. tulda and M. baccifera from nodal explants following validation of the species using the sequence of trnL-F intergenic spacer region is described. Effective axillary bud breaking was achieved at 3 mg/L of 6-benzylaminopurine (BAP) in MS medium. Importantly, combining 2 mg/L of kinetin (Kn) with 3 mg/L of BAP produced a synergistic effect for shoot multiplication in B. tulda and M. baccifera. Under optimized conditions in half-strength MS medium supplemented with 3 mg/L of indole-3-butyric acid (IBA), 10 mg/L of coumarin, and 3% sucrose, profuse production of dark-brown rhizome in B. tulda and abundant rooting (81.67%, P < 0.05, F = 15.46) for M. baccifera within 30 days were achieved. The established protocol and the validation of the reported species at the molecular level will be of help to stakeholders in edible bamboo trade to conserve gene-pool and increase productivity.

Scanning electron microscopy of pollen structure throws light on resolving Bambusa–Dendrocalamus complex: bamboo flowering evidence

Since the introduction of the new genus Sinocalamus in 1940 which is now dissociated into Bambusa and Dendrocalamus, molecular markers have long been unable to discern members of the Bambusa–Dendrocalamus complex. Rapid concerted evolution governed by high level of transition/transversion at the noncoding DNA regions has limited the ability of internal transcribed spacer (rDNA) and trnL-F intergenic spacer to resolve Bambusa and Dendrocalamus in phylogenetic analysis. Based on scanning electron microscopy (SEM) analysis of Bambusa vulgaris and Dendrocalamus manipureanus pollen development, we provided the evidence that there exists genus specificity in the development and structure of woody bamboo pollen which can serve as a benchmark for allocated new species into the genus Bambusa and Dendrocalamus substantiating molecular data.

Analysis on DNA Methylation-sensitive Amplified Polymorphism in Phyllostachys bambusoides During Flowering and Rejuvenation

To reveal epigenetic changes during flowering and rejuvenation of bamboo,we performed methylationsensitive amplification polymorphism(MSAP) analysis on the genomic DNA of Phyllostachys bambusoides Sieb.et Zucc.during flowering and asexual rejuvenation.Methylation level in P.bambusoides blades decreased during the flowering stage and then increased gradually after flowering when new bamboo stands were produced via asexual rejuvenation.Compared with non-flowering bamboo stands,29.09% of methylation sites were mutated during P.bambusoides flowering,with 17.88% of sites completely demethylated in flowering plants,which was much higher than that of the methylation sites(3.61%).The number and ratio of polymorphic sites changing in methylation status occurred in rejuvenated and non-flowering bamboo stands,especially demethylated sites,were lower than those in flowering bamboo stands.Methylation in floral organs was lower than that in blades in flowering P.bambusoides,and 28.58% of sites demonstrated changes in methylation status,mainly in the form of demethylation.

The draft genome of the fast-growing non-timber forest species moso bamboo (Phyllostachys heterocycla)

Bamboo represents the only major lineage of grasses that is native to forests and is one of the most important non-timber forest products in the world. However, no species in the Bambusoideae subfamily has been sequenced. Here, we report a high-quality draft genome sequence of moso bamboo (P. heterocycla var. pubescens). The 2.05-Gb assembly covers 95% of the genomic region. Gene prediction modeling identified 31,987 genes, most of which are supported by cDNA and deep RNA sequencing data. Analyses of clustered gene families and gene collinearity show that bamboo underwent whole-genome duplication 7-12 million years ago. Identification of gene families that are key in cell wall biosynthesis suggests that the whole-genome duplication event generated more gene duplicates involved in bamboo shoot development. RNA sequencing analysis of bamboo flowering tissues suggests a potential connection between drought-responsive and flowering genes.