l e t t e r sBamboo represents the only major lineage of grasses that is native to forests and is one of the most important nontimber 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 droughtresponsive and flowering genes.Bamboo is one of the most important non-timber forest products in the world. About 2.5 billion people depend economically on bamboo, and international trade in bamboo amounts to over 2.5 billion US dollars per year 1 . Bamboo has a rather striking life history, characterized by a prolonged vegetative phase lasting decades before flowering, thereby inhibiting genetic improvement. Recent genomic studies in bamboo have included genome-wide full-length cDNA sequencing 2 , chloroplast genome sequencing 3 , identification of syntenic genes between bamboo and other grasses 4 and phylogenetic analysis of Bambusoideae subspecies 5 . Fifty-nine simple sequence repeat markers from rice and sugarcane were used in the genetic diversity analyses of 23 bamboo species 6 , and 2 species-specific sequence-characterized amplified region markers were developed in the identification of different bamboo species 7 .Here, we report the draft genome of moso bamboo, a large woody bamboo that has ecological, economic and cultural value in Asia and accounts for ~70% of the total bamboo growth area. Comparative genome-wide analyses of bamboo to other grass species, including rice, maize and sorghum, yielded new genetic insights into the rapid and marked phenotypic and ecological divergence of bamboo and closely related grasses.The moso bamboo genome contains 24 pairs of chromosomes 8 (2n = 48) and is characteristic of a diploid (Supplementary Fig. 1a). We conducted a flow cytometry analysis and estimated that it had a genome size of 2.075 Gb (2C = 4.24 pg; Supplementary Fig. 1b), which was very close to that estimated in a previous report 9 .Because it is difficult to generate an inbred line of moso bamboo, owing to its infrequent sexual reproduction and the long periods of time between flowering intervals, we selected five plants from a single individual rhizome of the moso bamboo ecotype (P. heterocycla var. pubescens) and performed whole-genome shotgun sequencing. We generated 295 Gb of raw sequence data (approximately 147-fold coverage), including Illumina short reads and 10,327 pairs of BAC end ...

Two Gram-staining-negative, aerobic, non-spore-forming rod-shaped, non-motile bacteria, designated strains R156-2 T and T58-2 were isolated from the roots of Cymbidium goeringii. The colonies were yellow-pigmented. On the basis of 16S rRNA gene sequence similarity, strains R156-2 T and T58-2 were shown to be members of the genus Chitinophaga. Strains R156-2 T and T58-2 showed the greatest level of sequence similarity with Chitinophaga niabensis (96.0-96.3 %). The major menaquinone was MK-7. The main cellular fatty acids were iso-C 15 : 0 , C 16 : 1 v5c and iso-C 17 : 0 3-OH. Phenotypic and genotypic analyses indicated that strains R156-2 T and T58-2 could not be assigned to any recognized species. Therefore, strains R156-2 T and T58-2 represent a novel species of the genus Chitinophaga, for which the name Chitinophaga cymbidii sp. nov. is proposed. The type strain is R156-2 T (5ACCC. The DNA G+C content of this strain is 51.9 mol%.The genus Chitinophaga, the type genus of the family Chitinophagaceae (Kämpfer et al. 2011), was first described by Sangkhobol & Skerman (1981). At the time of writing, the genus includes 13 species with validly published names. These are Chitinophaga pinensis (Sangkhobol & Skerman, 1981) The diversity of endophytic bacteria was large in the roots of Cymbidium goeringii. Endophytic isolates from the roots of Cymbidium goeringii were grouped into six phyla, including Alphaproteobacteria (50.9 %), Gammaproteobacteria (34.6 %), Betaproteobacteria (6.7 %), Firmicutes (5.2 %), Actinobacteria (1.9 %) and Bacteroidetes (0.7 %), and the dominant genera were Rhizobium (48.3 %) and Dyella (25.8 %) (our unpublished results). A total of 57 indole-3-acetic acidproducing strains and 47 siderophore-producing strains were isolated from the root interior of Cymbidium goeringii (Liu et al., 2010;Sun et al., 2011). In this study, we describe novel strains of a member of the genus Chitinophaga, which were isolated from the root interior of Cymbidium goeringii.Cymbidium goeringii samples, which have grown for 5 years in a greenhouse at the Chinese Academy of Forestry (Beijing, China), were obtained in October 2008. The roots of Cymbidium goeringii were separated from the soil, washed with tap water and surface-sterilized with 70 % ethanol for 3 min, with 3.0 % sodium hypochlorite solution for 2 min and rinsed with 70 % ethanol for 30 s followed by rinsing with sterile distilled water. To confirm that the sterilization process was successful, the aliquots of the sterile distilled water used in the final rinse were set on trypticase soy agar (TSA) medium plates. Samples (1 g) of surfacesterilized roots were ground with a sterile mortar and diluted with sterile 0.85 % sodium chloride using the standard dilution plating technique and then incubated 28 uC for 4 days. Strains R156-2 T and T58-2 were isolated from the plates of R2A agar (Difco) and trypticase soy agar (Difco), respectively. The two strains were purified using the streak plate method and then stored at 280 u C as glycerol suspension (20 %, v/v) a...

Twigs of 2-3-year-old Platanus occidentalis L. were used as experimental material to find the causes for the contamination and browning in the initial stages of tissue cultures. To compare the degree of browning of explants picked off from different growing seasons, the experimental material was excised from trees on each of the first ten days in January, March, May and July, 2006. The results indicated that the contamination and browning rates of the material cut off in January (14.2% and 30.6%, respectively) and March were somewhat lower than those in July. The pretreatment of soaking the explants in different anti-oxidants and absorbents at the same time could diminish some side effects. The pretreatment of using 10 g·L -1 vitamin C reduced the contamination and browning rate effectively. An orthogonal experiment showed that the optimal factor and level arrangement is 0.5 mg·L -1 BA, 2.0 g·L -1 active carbon and 1.5 g·L -1 PVP which resulted in a browning rate of only 16.5%. In general, sampling period, physical properties and pretreatment of explants are the main factors responsible for the contamination and browning of material in the initial stages of P. occidentalis tissue cultures.