Yan X.,State Key Laboratory for Conservation and Utilization of Subtropical Agro Bioresources |
Bai M.,State Key Laboratory for Conservation and Utilization of Subtropical Agro Bioresources |
Ning X.,State Key Laboratory for Conservation and Utilization of Subtropical Agro Bioresources |
Ouyang H.,Fujian Institute of Subtropical Botany |
And 4 more authors.
American Journal of Botany | Year: 2015
PREMISE OF THE STUDY: Spatiotemporal features of microsporogenesis may provide important clues about the evolution of microsporogenesis in seed plants. One cellular feature that attracts special attention is advance cell wall ingrowths (ACWIs) at future cytokinetic sites in microsporocytes since they have been found only in species of an ancient lineage of angiosperms, Magnolia, and in much less detail, of an ancient lineage of gymnosperms, cycads. Further investigation into microsporogenesis in a cycad species may yield knowledge critical to understanding the establishment of ACWIs as an important feature for comparative studies of microsporogenesis in seed plants. METHODS: Bright-field and epifluorescence microscopy, confocal laser scanning microscopy, and transmission electron microscopy were used to investigate the microsporogenic process in Macrozamia communis, a species in the Zamiaceae family of cycads. KEY RESULTS: In prophase-II microsporocytes in M. communis, ACWIs form as a callose ring between the newly formed nuclei and are not accompanied by cytokinetic apparatuses such as mini-phragmoplasts, wide tubules, or wide tubular networks. Shortly after the second nuclear division, new ACWIs, albeit thinner than the previous ACWIs, form between the newly formed nuclei. Subsequent cell plate formation in the planes of the ACWIs typically results in tetragonal tetrads. CONCLUSIONS: Cytokinesis at the cell periphery is initiated earlier than cell plate formation in the cell interior in microsporogenesis in M. communis. The cellular features uncovered in M. communis may serve as useful reference features for comparative studies of microsporogenesis in plants. © 2015 Botanical Society of America.
Li Y.-Q.,South China Agricultural University |
Kong D.-X.,CAS Institute of Botany |
Wu H.,South China Agricultural University |
Wu H.,Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm |
Wu H.,State Key Laboratory for Conservation and Utilization of Subtropical Agro Bioresources
Industrial Crops and Products | Year: 2013
In this work, the volatile compounds of cinnamon barks from three species and seven habitats were detected and identified for the first time by GC-MS and FTIR analysis. GC-MS analysis indicated that the main compound in the volatile oils of nine samples was trans-cinnamaldehyde (66.28-81.97%). Cinnamomum loureirii had the highest volatile oil yield (3.08%) and in that yield was a high percentage of trans-cinnamaldehyde (81.97%). Cinnamomum verum contained significant quantities of eugenol, and Cinnamomum cassia had more abundant α-guaiene compared with C. loureirii and C. verum. Hierarchical cluster analysis, similarity evaluation and principal component analysis showed that the nine samples were effectively identified and evaluated. Load factor analysis revealed that the differences in the volatile compounds of the nine samples were mainly reflected in the aldehyde, alcohol, alkane and eugenol contents. Our research indicated that GC-MS and FTIR techniques, combined with chemometrics, proved to be an effective strategy for identifying the species and for determining their geographical distribution, especially in the assessment of cinnamon quality for use in raw herbal medicines. © 2012 Elsevier B.V.
Huang H.,South China Agricultural University |
Huang H.,State Key Laboratory for Conservation and Utilization of Subtropical Agro Bioresources |
Huang H.,Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm |
Li J.,South China Agricultural University |
And 9 more authors.
Plant Biotechnology | Year: 2014
Neolamarckia cadamba is a fast-growing and deciduous tropical hardwood with anatomical, morphological, and chemical characteristics that make it suitable for building materials, pulp production, and medicine raw materials. In this study, a protocol for direct adventitious shoot organogenesis and plant regeneration from the aseptic cotyledons of N. cadamba was established. The cotyledons with petioles from 3-week-old seedlings were used for adventitious shoot induction in DCR medium containing 22.20 μM 6-benzyladenine (BA) and 0.27 μM α-naphthaleneacetic acid (NAA). The frequency of adventitious shoot induction was 54.2%. Micro-shoots were then transferred to MS medium containing 4.44 μM BA and 0.25 μM indole-3-butyric acid (IBA) for shoot propagation. Available shoots per explant reached 5.9. The highest rooting percentage (98.3%) was obtained when shoots were transferred to half-strength MS medium supplemented with 0.27 μM NAA and 0.25 μM IBA. The rooted plantlets could be successfully acclimatized to a greenhouse with more than 95% survival, and the regenerated plants showed the same morphological characteristics as those of the control plants in fields. Histological observations revealed that the adventitious shoots only originated from the epidermal tissue around the edge of the cut zone of the cotyledonary petiole. © 2014 The Japanese Society for Plant Cell and Molecular Biology.
Li P.,Beijing Forestry University |
Li P.,South China Agricultural University |
Zhan X.,South China Agricultural University |
Zhan X.,State Key Laboratory for Conservation and Utilization of Subtropical Agro Bioresources |
And 31 more authors.
Forests | Year: 2015
Sequence-related amplified polymorphism (SRAP) markers were used to investigate the genetic diversity among 30 populations of Toona ciliata Roem. sampled from the species' distribution area in China. To analyze the polymorphism in the SRAP profiles, 1505 primer pairs were screened and 24 selected. A total of 656 SRAP bands ranging from 100 to 1500 bp were acquired, of these 505 bands (77%) were polymorphic. The polymorphism information content (PIC) values ranged from 0.32 to 0.45, with an average of 0.41. An analysis of molecular variance (AMOVA) indicated that the most significant variation was attributable to differences among the populations and that variation within the populations was small. STRUCTURE analysis divided the 30 populations into two parts. The unweighted pair group method of arithmetic averages (UPGMA) clustering and principal coordinates analysis (PCoA) showed that the 30 populations could be classified into four types. The results demonstrate a clear geographical trend for T. ciliata in China and provide a theoretical basis for future breeding and conservation strategy of T. ciliata. © 2015 by the authors; licensee MDPI, Basel, Switzerland.
Ouyang K.,South China Agricultural University |
Ouyang K.,Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm |
Li J.,South China Agricultural University |
Li J.,Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm |
And 14 more authors.
PLoS ONE | Year: 2016
Neolamarckia cadamba is a fast-growing tropical hardwood tree that is used extensively for plywood and pulp production, light furniture fabrication, building materials, and as a raw material for the preparation of certain indigenous medicines. Lack of genomic resources hampers progress in the molecular breeding and genetic improvement of this multipurpose tree species. In this study, transcriptome profiling of differentiating stems was performed to understand N. cadamba xylogenesis. The N. cadamba transcriptome was sequenced using Illumina paired-end sequencing technology. This generated 42.49 G of raw data that was then de novo assembled into 55,432 UniGenes with a mean length of 803.2bp. Approximately 47.8% of the UniGenes (26,487) were annotated against publically available protein databases, among which 21,699 and 7,754 UniGenes were assigned to Gene Ontology categories (GO) and Clusters of Orthologous Groups (COG), respectively. 5,589 UniGenes could be mapped onto 116 pathways using the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database. Among 6,202 UniGenes exhibiting differential expression during xylogenesis, 1,634 showed significantly higher levels of expression in the basal and middle stem segments compared to the apical stem segment. These genes included NAC and MYB transcription factors related to secondary cell wall biosynthesis, genes related to most metabolic steps of lignin biosynthesis, and CesA genes involved in cellulose biosynthesis. This study lays the foundation for further screening of key genes associated with xylogenesis in N. cadamba as well as enhancing our understanding of the mechanism of xylogenesis in fast-growing trees. © 2016 Ouyang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.