Synteny of Cotton SSR Markers Genomes Paves the Way for Resistance Against Black Root Rot Disease in Cotton

Background: Black root rot disease is documented for substantial reducing cotton yield and fiber quality. The isolation of candidate resistant genes in tetraploid genome AADD cotton species (2n=4x=52) remains challenging in the absence of research of black root rot resistance on progenitor DD genome diploid cotton. In this study, by exploiting Phytozome database, a comparative map of the black root rot-resistance quantitative trait loci in DD genome was constructed.Methods: Simple sequence repeats markers associated with these three quantitative trait loci in the AA genome were used as “anchored-probes” frameworks for establishing relationships between the two cotton genomes AA and DD.Results: Our findings showed that there was conserved orders among mapped simple sequence repeats markers on AA genome and the physical map of these simple sequence repeats markers on DD genome.Conclusion: It was suggested that the syntenic loci on chromosome 2, 7 and 11 on DD genome could harbor the resistance gene against the black root rot disease. This study could serve as a fundamental step in isolating and introducing the resistance gene against black root rot into elite cotton cultivars.Keywords: Comparative mapping; Resistance gene; Phytozome; Simple sequence repeats; Quantitative trait loci    

Molecular phylogeny of Annonaceae species from Binh Chau-Phuoc Buu Nature Reserve based on two chloroplast gene regions

In this study, based on molecular biology techniques, the matK and trnL-F regions of ten Annonaceae species grown in Binh Chau-Phuoc Buu Nature Reserve, Vietnam were successfully amplified and sequenced for the first time. Along with other highly homologous DNA sequences from the GenBank database, the molecular phylogeny of ten studied species was also established. By using the alignment tool of NCBI database, the percentage of identity among sequences of studied species was also presented. The study aims to partially contribute to the further understanding of the evolutionary relationships among Annonaceae species

Biomolecular evaluation of three contrasting rice cultivars (Oryza sativa L.) in salt stress response at seedling stage.

Salt contamination of soils due to climate change faces a severe environmental issue that affects crop production today. However, the response mechanism in plants to salt stress is not fully understood. The present study investigated molecular and biochemical changes under salt stress in rice seedlings of three rice cultivars, i.e., AGPPS114 (salt-tolerant), OM6967 (moderately tolerance), VD20 (salt-sensitive). Increasing salt concentration leads to a reduction in shoot/root length but different levels among the cultivars. In contrast, reactive oxygen species (ROS) accumulation and lipid peroxidation increased progressively with increasing salt concentration and time course treatment. However, at 250 ?M of NaCl, these parameters were more adversely affected in VD20 than AGPPS114 and OM6967. Using ICP showed that Na+ accumulation in rice root increased gradually with increasing NaCl concentrations in all cultivars under salt treatment but was low in salt-sensitive cultivar VD20 compared to other cultivars. Antioxidant enzyme activity analysis indicated catalase (CAT) and superoxide dismutase (SOD) were induced during salt treatment in all cultivars. The results also showed greater proline and glycine betaine accumulation in the AGPPS114 than OM6976 and VD20. qPCR indicated a significant difference in transcript levels of the Na+-transporter gene OsSOS1, OsNHX1 and OsHKT1s in AGPPS114 and OM6967 cultivars compared to VD20 cultivar. In summary, the active regulation of genes related to Na+ transport at the transcription level and with high glycine betaine and proline accumulation levels may be involved in salt tolerance mechanisms and thus might be useful for selecting tolerant plants

Molecular identification of three Habenaria species from Binh Chau-Phuoc Buu Nature Reserve, Vietnam

The present provides molecular data for species of Habenaria diphylla (Nimmo) Dalzell, H. khasiana Hook.f. and H. rostellifera Rchb.f. collected from Binh Chau-Phuoc Buu Nature Reserve, Vietnam for the first time. Along with other DNA sequences from GenBank database, the phylogenetic trees for Habenaria species from Vietnam have been established

Chemical profiles and biological activities of acetone extracts of nine Annonaceae plants

This study investigated the chemical components and bioactivities of acetone leaf extracts of nine Annonaceae plants collected in the Binh Chau-Phuoc Buu Nature Reserve, Vietnam. A total of 182 constituents were identified, with linolenic acid, diaeudesmin, germacrene D, 1-octadecenoic acid, 8-(3-octyl-2-oxiranyl)-1-octanol, oleic acid, and phenylmethyl ester being the major compounds. The antimicrobial activity of the extracts was evaluated using a disc diffusion assay. Eight of the nine extracts, except for the Mitrephora thorelii extract, showed an inhibition effect against Bacillus cereus and Staphylococcus aureus. The antioxidant activity of the extracts was determined using DPPH assay, and the cytotoxic activity was deter mined using SRB assay. The results showed that the acetone extracts of Artabotrys hexapetalus, Uvularia grandiflora, Polyalthia luensis, Xylopia pierrei, Sphaerocoryne affinis, Desmos cochinchinensis, Uvaria littoralis, Mitrephora thorelii, and Goniothalamus touranensis had significant activity with IC50 for the DPPH radical scavenging activity ranging from 18.56 to 702.33 μg/mL, and the IC50 for the cytotoxic effects ranged from 5.39 to 251.77 μg/mL. Overall, the results obtained provide experimental evidence for the potential use of these plants in medicine and other related fields

Transcriptome analysis of copper stress response in rice seedling using DNA microarray

Heavy metal contamination along with the increase in food demand are a primary concern in Vietnam and all over the world. In order to enhance crop tolerance to unfavorable cultivation conditions including heavy metal toxicity, understanding of plant response system under the effect of heavy metals is necessary. In the current study, physiological, biochemical and transcriptomic changes of rice seedings (Oryza sativa L. cv. IR64) were investigated under copper (Cu) stress. Root elongation and root fresh weight were decreased whereas accumulation of copper in root was enhanced significantly with increasing copper concentration from 2.5 to 15 M. In addition, copper induced endogenous reactive oxygen species (ROS) generation and activated isoenzymes of superoxide dismutase (SOD) and catalase (CAT). The molecular mechanism of rice roots in response to copper toxicity at mRNA expression level was analyzed by microarray technique. Functions and roles of genes were also analyzed by bioinformatic tools AgriGO and MapMan. Gene ontology analysis revealed that 1900 Cu responsive genes were involved in phytohormones, reactive oxygen species, signaling pathways, transcription factors, transport activities, antioxidant defense systems. Through phytohormones and reactive oxygen species, Cu may inhibit rice root growth. Phytohormones and reactive oxygen species can also be signal molecules in signaling pathways with the participation of mitogen-activated protein kinase (MAPK) cascades, and transcription factors in response to Cu stress. Detoxification and protection mechanisms may involve transport activities and antioxidant defense systems during Cu treatment. These results may provide new insights into mechanisms of rice plant to tolerate with Cu toxicity conditions

Chemical composition and antibacterial activities of essential oils from Homalomena pierreana (Araceae)

30-37Homalomena is a genus of the Araceae family which contains several remedies used extensively in traditional Vietnamese medicine. H. pierreana is a rare plant species of Homalomena genus and found only in Phu Quoc National Park, Phu Quoc Island, Kien Giang Province, Vietnam. Therefore, the number of studies about this species is limited and the bioactivity of this species is still unknown. In this study, the chemical composition of essential oils was investigated which was isolated from leaves and rhizomes of H. pierreana at the first time by GC-MS. Eight and twelve compounds were identified from the essential oils of rhizomes and leaves, respectively. The major component from both the rhizomes and the leaves was aromadendrene (44 and 48%, respectively). Furthermore, the antibacterial activity of essential oils collected from leaves and rhizomes of H. pierreana was investigated and it was observed that the essential oil of rhizomes could inhibit the growth of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, while the essential oil of leaves exhibited an inhibitory effect against Staphylococcus aureus and Escherichia coli.</em

CAMELLIA SINENSIS VAR. MADOENSIS (SECT. THEA, THEACEAE), A NEW TAXON FROM VIETNAM

Camellia sinensis var. madoensis is described and illustrated as a new variety of Camellia sinensis (section Thea, Theaceae) from Xuan Loc Commune, Song Cau District, Phu Yen Province. The new variety is easily distinguishable from C. sinensis var. sinensis by style free ½ to the base. The ITS sequence of this variety is also different from that of Camellia sinensis and its other varieties, while the matK gene sequences are nearly identical among Camellia taxa.Camellia sinensis var. madoensis được mô tả và minh họa với vai trò là một thứ mới của Camellia sinensis (section Thea, Theaceae) ghi nhận tại xã Xuân Lộc, huyện Sông Cầu, tỉnh Phú Yên. Thứ mới này có thể dễ dàng phân biệt với C. sinensis var. sinensis bởi vòi nhụy rời ½ tính từ đế. Trình tự ITS của thứ này cũng khác với Camellia sinensis và các thứ khác của nó

Habenaria diphylla (Nimmo) Dalzell (Orchidaceae), new record for the flora of Vietnam

Habenaria diphylla (Nimmo) Dalzell is reported for the first time as a new discovery for the flora of Vietnam based on the specimens collected in Binh Chau-Phuoc Buu Nature Reserve, Ba Ria-Vung Tau Province. The present study provided the detailed characteristics of the species including detailed photographs of the morphological characteristics, the cross section of the leaf, inflorescence axis and root. Furthermore, the information about the species, including distribution, habitat, ecology and conservation status were also provided