Identification and characterization of the cupin_1 domain-containing proteins in ma bamboo (Dendrocalamus latiflorus) and their potential role in rhizome sprouting.

Cupin_1 domain-containing protein (CDP) family, which is a member of the cupin superfamily with the most diverse functions in plants, has been found to be involved in hormone pathways that are closely related to rhizome sprouting (RS), a vital form of asexual reproduction in plants. Ma bamboo is a typical clumping bamboo, which mainly reproduces by RS. In this study, we identified and characterized 53 Dendrocalamus latiflorus CDP genes and divided them into seven subfamilies. Comparing the genetic structures among subfamilies showed a relatively conserved gene structure within each subfamily, and the number of cupin_1 domains affected the conservation among D. latiflorus CDP genes. Gene collinearity results showed that segmental duplication and tandem duplication both contributed to the expansion of D. latiflorus CDP genes, and lineage-specific gene duplication was an important factor influencing the evolution of CDP genes. Expression patterns showed that CDP genes generally had higher expression levels in germinating underground buds, indicating that they might play important roles in promoting shoot sprouting. Transcription factor binding site prediction and co-expression network analysis indicated that D. latiflorus CDPs were regulated by a large number of transcription factors, and collectively participated in rhizome buds and shoot development. This study significantly provided new insights into the evolutionary patterns and molecular functions of CDP genes, and laid a foundation for further studying the regulatory mechanisms of plant rhizome sprouting.

Complete chloroplast genome sequence of Gigantochloa verticillata (Bambusodae).

Gigantochloa verticillata is produced in Mengla and Jinghong, Yunnan Province, China, and cultivated in Hong Kong. Vietnam, Thailand, India, Indonesia, and Malaysia are distributed and cultivated. We determined the complete chloroplast genome sequence for G. verticillata using Illumina sequencing data. The complete chloroplast sequence is 139,489 bp, including large single-copy (LSC) region of 83,062 bp, small single-copy (SSC) region of 12,877 bp, and a pair of invert repeats (IR) regions of 21,775 bp. Plastid genome contain 132 genes, 85 protein-coding genes, 39 tRNA genes, and 8 rRNA genes. Phylogenetic analysis based on 23 chloroplast genomes indicates that G. verticillata is closely related to Dendrocalamus latiflorus in Bambusodae.

Complete chloroplast genome sequence of Bambusa pervariabilis (Bambusodae).

Bambusa pervariabilis is mostly produced in south China; usually cultivated on the banks of the rivers and near villages. We determined the complete chloroplast (cp) genome sequence of B. pervariabilis using Illumina sequencing data. The complete cp sequence is 139,393 bp, include large single-copy (LSC) region of 82,969 bp, small single-copy (SSC) region of 12,874 bp, a pair of invert repeats (IR) regions of 21,775 bp. Plastid genome contain 132 genes, 85 protein-coding genes, 39 tRNA genes, and 8 rRNA genes. Phylogenetic analysis based on 28 cp genomes indicates that B. pervariabilis is closely related to Bambusa multiplex in Bambusodae.

[Effects of exogenous abscisic acid (ABA) on the photosynthesis and chlorophyll fluorescence parameters of Tripterygium wilfordii seedlings exposed to low temperature].

Taking one year-old Tripterygium wilfordii cutting seedlings as test materials, this paper studied the effects of foliar spraying 0, 5, 10, 15, 20, and 25 mg x L(-1) of abscisic acid (ABA) on the leaf photosynthesis and chlorophyll fluorescence characteristics of the seedlings under low temperature stress. Spraying 20 mg x L(-1) of ABA increased the cold- resistance of the seedlings significantly, manifesting in the slowing down of the decrease amplitudes of leaf net photosynthetic rate (P(n)), transpiration rate (T(r)), stomatal conductance (g(s)), and intercellular CO2 concentration (C(i)) and the increase of photosynthetic capacity. After 6 days exposure to low temperature, the initial fluorescence (F(o)) decreased with increasing concentration of applied ABA, the maximum fluorescence (F(m)) and maximal photochemical yield (F(v)/F(m)) increased, the actual photochemical efficiency of system II (phi(PSII)) and photochemical quenching coefficient (q(P)) increased after an initial decrease, and the non-photochemical quenching coefficient (q(N)) showed a 'decreasing-increasing-decreasing' trend. The P(n), g(s), q(P), F(m), and F(v)/F(m) reached their peak values at 20 mg x L(-1) of ABA. In all treatments, with the increase of photosynthetically active radiation (PAR), the relative electron transport rate (rETR) increased first and decreased then, reached the peak when the PAR was 395 micromol x m(-2) x s(-1), and the peak value of the rETR in treatments 25 and 20 mg x L(-1) of ABA was 17.1% and 5.2% higher than that of the control, respectively. The light response curves of the psi(PSII) decreased with increasing PAR, whereas those of q(N) performed in adverse.