It is important to research the rules about accumulation and distribution of arsenic and cadmium by tea plants, which will give us some scientific ideas about how to control the contents of arsenic and cadmium in tea. In this study, by field investigation and pot trial, we found that mobility of arsenic and cadmium in tea plants was low. Most arsenic and cadmium absorbed were fixed in feeding roots and only small amount was transported to the above-ground parts. Distribution of arsenic and cadmium, based on their concentrations of unit dry matter, in tea plants grown on un-contaminated soil was in the order: feeding roots>stems approximately main roots>old leaves>young leaves. When tea plants were grown on polluted soils simulated by adding salts of these two metals, feeding roots possibly acted as a buffer and defense, and arsenic and cadmium were transported less to the above-ground parts. The concentration of cadmium in soil significantly and negatively correlated with chlorophyll content, photosynthetic rate, transpiration rate and biomass production of tea plants.
Arsenic ; metabolism ; Biomass ; Cadmium ; metabolism ; Camellia sinensis ; metabolism ; Chlorophyll ; metabolism ; Photochemistry ; Plant Shoots ; metabolism ; Tea ; metabolism

Most current research in the field of adventitious shoot formation is focused on the regulatory function of a single gene. However, a systematic transcriptomic analysis of the early adventitious shoot formation is still lacking. Here, we analyzed the transcriptome profiling of the early adventitious shoot formation in Arabidopsis by RNA-seq high throughput sequencing technology, and identified 2 457 differentially expressed genes. Detailed categorization revealed that these genes were mainly involved in hormone homeostasis or signal transduction, callus and lateral root formation, shoot apical meristem development and photosynthesis. Further pathway enrichment analysis showed that genes involved in phenylalanine metabolism and phenylpropanoid biosynthesis were significantly enriched. Moreover, exogenous phenylalanine could repress adventitious shoot formation, indicating that phenylalanine metabolism and phenylpropanoid biosynthesis might be important for adventitious shoot formation.
Arabidopsis ; genetics ; Gene Expression Profiling ; methods ; Gene Expression Regulation ; Genes, Plant ; Phenylalanine ; pharmacology ; Plant Shoots ; genetics ; growth & development

OBJECTIVETo develop the reproducible in vitro propagation protocols for the medicinally important plants viz., Achyranthes aspera (A. aspera) L. and Achyranthes bidentata (A. bidentata) Blume using nodal segments as explants.

METHODSYoung shoots of A. aspera and A. bidentata were harvested and washed with running tap water and treated with 0.1% bavistin and rinsed twice with distilled water. Then the explants were surface sterilized with 0.1% (w/v) HgCl2 solutions for 1 min. After rinsing with sterile distilled water for 3-4 times, nodal segments were cut into smaller segments (1 cm) and used as the explants. The explants were placed horizontally as well as vertically on solid basal Murashige and Skoog (MS) medium supplemented with 3% sucrose, 0.6% (w/v) agar (Hi-Media, Mumbai) and different concentration and combination of 6-benzyl amino purine (BAP), kinetin (Kin), naphthalene acetic acid (NAA) and indole acetic acid (IAA) for direct regeneration.

RESULTSAdventitious proliferation was obtained from A. aspera and A. bidentata nodal segments inoculated on MS basal medium with 3% sucrose and augmented with BAP and Kin with varied frequency. MS medium augmented with 3.0 mg/L of BAP showed the highest percentage (93.60±0.71) of shootlets formation for A. aspera and (94.70±0.53) percentages for A. bidentata. Maximum number of shoots/explants (10.60±0.36) for A. aspera and (9.50±0.56) for A. bidentata was observed in MS medium fortified with 5.0 mg/L of BAP. For A. aspera, maximum mean length (5.50±0.34) of shootlets was obtained in MS medium augmented with 3.0 mg/L of Kin and for A. bidentata (5.40±0.61) was observed in the very same concentration. The highest percentage, maximum number of rootlets/shootlet and mean length of rootlets were observed in 1/2 MS medium supplemented with 1.0 mg/L of IBA. Seventy percentages of plants were successfully established in polycups. Sixty eight percentages of plants were well established in the green house condition. Sixty five percentages of plants were established in the field.

CONCLUSIONSThe results have shown that use of nodal buds is an alternative reproducible and dependable method for clonal propagation of A. aspera and A. bidentata. The high rate of direct shoot-root multiplication and their high rate of post-hardening survival indicate that this protocol can be easily adopted for commercial large scale cultivation.

Achyranthes ; growth & development ; Culture Media ; chemistry ; Plant Roots ; growth & development ; Plant Shoots ; growth & development ; Plants, Medicinal ; growth & development ; Survival Analysis

In order to reveal the main nutrients and functional ingredients in the shoots of Polygonatum cyrtonema, the polysaccharides, proteins, amino acids, and total phenols were determined. The tested samples cultured in Ma'nijiaonong, Hengtang village, Tianmushan town, Lin'an, Zhejiang, which were collected from three provenances(Pan'an and Longquan in Zhejiang and Qingyang in Anhui). The results showed that the polysaccharide content of the shoots varied from 2.34% to 12.73%, roughly one-third of rhizomes. The protein content varied from 107.75 to 192.49 mg·g~(-1), nearly 5.50 times more than rhizomes. Moreover, the average of total amino acid content was 193.13-248.74 mg·g~(-1), approximately 4.16 times of rhizomes. And the essential amino acids account for 35.57%-39.44% of the total amino acids content, which was close to the standard of the ideal protein proposed by FAO/WHO(the essential amino acid/total amino acid is about 40%). In addition, the taste amino acids(TaAA) changed from 160.12 to 208.29 mg·g~(-1), revealing the material basis of "shoots were extremely delicious" in Chinese ancient herbal medicine. Additionally, the total phenols varied from 51.21-58.76 mg·g~(-1), about 2.96 times of rhizomes. The DPPH free radical scavenging rate of tested shoots was over 95%, which obviously superior to rhizomes. Therefore, the shoots of P. cyrtonema is a very high-quality vegetable and functional food with good development potential. Furthermore, the main nutrients and functional substances in P. cyrtonema shoots are closely related to the provenances and harvesting seasons. It is important to improve the quality and yield of the shoots by strengthening the variety of breeding and cultivation techniques.
Amino Acids, Essential/analysis* ; Functional Food ; Nutrients/analysis* ; Plant Proteins, Dietary/analysis* ; Plant Shoots/chemistry* ; Polygonatum/chemistry* ; Polysaccharides/analysis* ; Rhizome

The effect of sugars, gibberellic acid (GA3) and abscisic acid (ABA) on somatic embryogenesis from internodal explant-derived callus of Tylophora indica (Burm. f.) Merrill has been investigated. Embryogenic calli were produced from internodal explants and the best result was achieved by using MS medium supplemented with 4micromol/L 2, 4-Dichlorophenoxyacetic acid (2, 4-D). Up to 69% of such embryogenic calli differentiated into somatic embryos with an average of 25 embryos per explant (per gram of the calli) on Murashige and Skoog (MS) medium containing 6micromol/L kinetin (Kn). The individual effect of sucrose and glucose together with 6micromol/L Kn was evaluated. There was a significant difference among concentrations of sugar and among kinds of sugar tested in somatic embryogenesis. Sucrose at 200mmol/L with 6micromol/L Kn gave rise to a maximum embryogenesis (71%) with an average of 49 embryos per explant. However, glucose together with 6micromol/L Kn or a combination of glucose, sucrose and 6micromol/L Kn reduced the percentage of embryogenesis culture and the number of embryos per explant. The presence of GA3 and ABA at particular concentrations promoted somatic embryogenesis in T. indica. The addition of 10mol/L GA3 into the 200mmol/L sucrose-containing medium gave a 98% embryogenesis response with an average of 51 embryos per explant. Somatic embryogenesis was significantly enhanced by the addition of 2micromol/L ABA to 200mmol/L sucrose-containing medium. On this medium 95% embryogenesis with an average of 44 embryos per explant was observed. The study reported here indicates that 200mmol/L sucrose with 6micromol/L Kn, 200mmol/L sucrose with 10micromol/L GA3 and 200mmol/L sucrose with 2micromol/L ABA significantly improved somatic embryogenesis in T. indica whereas glucose alone or in combination with sucrose had an inhibitory role. The embryos obtained developed normally and were easily converted into plants.
Abscisic Acid ; pharmacology ; Carbohydrates ; pharmacology ; Culture Media ; Culture Techniques ; Gibberellins ; pharmacology ; Plant Shoots ; embryology ; growth & development ; Tylophora ; embryology ; growth & development

Results from an innovative approach to improve remediation in the rhizosphere by encouraging healthy plant growth and thus enhancing microbial activity are reported. The effect of arbuscular mycorrhizal fungi (Am) on remediation efficacy of wheat, mungbean and eggplant grown in soil spiked with polyaromatic hydrocarbons (PAH) was assessed in a pot experiment. The results of this study showed that Am inoculation enhanced dissipation amount of PAHs in planted soil, plant uptake PAHs, dissipation amount of PAHs in planted versus unplanted spiked soil and loss of PAHs by the plant-promoted biodegradation. A number of parameters were monitored including plant shoot and root dry weight, plant tissue water content, plant chlorophyll, root lipid content, oxido-reductase enzyme activities in plant and soil rhizosphere and total microbial count in the rhizospheric soil. The observed physiological data indicate that plant growth and tolerance increased with Am, but reduced by PAH. This was reflected by levels of mycorrhizal root colonization which were higher for mungbean, moderate for wheat and low for eggplant. Levels of Am colonization increased on mungbean > wheat > eggplant. This is consistent with the efficacy of plant in dissipation of PAHs in spiked soil. Highly significant positive correlations were shown between of arbuscular formation in root segments (A)) and plant water content, root lipids, peroxidase, catalase polyphenol oxidase and total microbial count in soil rhizosphere as well as PAH dissipation in spiked soil. As consequence of the treatment with Am, the plants provide a greater sink for the contaminants since they are better able to survive and grow.
Biodegradation, Environmental* ; Catalase ; Catechol Oxidase ; Chlorophyll ; Colon ; Fungi* ; Hydrocarbons ; Hydrocarbons, Aromatic* ; Peroxidase ; Plant Shoots ; Plants ; Rhizosphere* ; Soil* ; Solanum melongena ; Triticum

Transcriptional regulation is one of the major regulations in plant adventious shoot regeneration, but the exact mechanism remains unclear. In our study, the RNA-seq technology based on the IlluminaHiSeq 2000 sequencing platform was used to identify differentially expressed transcription factor (TF) encoding genes during callus formation stage and adventious shoot regeneration stage between wild type and adventious shoot formation defective mutant be1-3 and during the transition from dedifferentiation to redifferentiation stage in wildtype WS. Results show that 155 TFs were differentially expressed between be1-3 mutant and wild type during callus formation, of which 97 genes were up-regulated, and 58 genes were down-regulated; and that 68 genes were differentially expressed during redifferentiation stage, with 40 genes up-regulated and 28 genes down-regulated; whereas at the transition stage from dedifferentiation to redifferention in WS wild type explants, a total of 231 differentially expressed TF genes were identified, including 160 up-regualted genes and 71 down-regulated genes. Among these TF genes, the adventious shoot related transcription factor 1 (ART1) gene encoding a MYB-related (v-myb avian myeloblastosis viral oncogene homolog) TF, was up-regulated 3 217 folds, and was the highest up-regulated gene during be1-3 callus formation. Over expression of the ART1 gene caused defects in callus formation and shoot regeneration and inhibited seedling growth, indicating that the ART1 gene is a negative regulator of callus formation and shoot regeneration. This work not only enriches our knowledge about the transcriptional regulation mechanism of adventious shoot regeneration, but also provides valuable information on candidate TF genes associated with adventious shoot regeneration for future research.
Arabidopsis ; growth & development ; Arabidopsis Proteins ; physiology ; Gene Expression Regulation, Plant ; Genes, Plant ; Plant Shoots ; growth & development ; RNA ; Regeneration ; Seedlings ; growth & development ; Transcription Factors ; physiology ; Up-Regulation

OBJECTIVETo construct the fast propagation system of Houttuynia cordata Thunb. new line by selecting the proper type and concentration of plant growth regulators and proper explants.

METHODThe different explants of Houttuynia cordata new line were cultured on MS media with different concentration of different plant grow regulators.

RESULTStem node over-ground and shoot tip were optimum explants for fast propagation. The stem which node grew on MS medium with KT at 0.5 mg x L(-1) could induce more leaves and grow higher. The shoot tip cultured on MS medium with 1.0 mg x L(-1) 6-BA could induce better callus. Adventitious shoots were better achieved from over-ground nodal explants cultured on MS medium supplemented with 6-BA at 1.0 mg x L(-1) and NAA at 0.2 mg x L(-1), or 6-BA at 0.5 mg x L(-1) and NAA at 0.2 mg x L(-1). MS medium with IAA at 0.2 mg x L(-1) was the best one on inducing roots.

CONCLUSIONThe propagat coefficient can be highly improved by inducing adventitious shoots through stem node over-ground, and thus plentiful seeds for production can be provided.

Culture Media ; Plant Growth Regulators ; pharmacology ; Plant Shoots ; growth & development ; Plant Stems ; growth & development ; Plants, Medicinal ; growth & development ; Saururaceae ; growth & development ; Tissue Culture Techniques ; methods

OBJECTIVETo study the effect of changing source-sink ratio on dry matter accumulation yield, distribution and interrelated physiological index of Cynanchum bungei.

METHODBud, fruit or side tress of C. bungei were picked artificially in the development stage. LAI, chlorophyll content, photosynthesis of single leaf, accumulation and distribution of dry matter at different and treatments were measured. The untreated plant was used as the control.

RESULTAlthough leaf decrease can be compensated by the increasing photosynthesis rate of single leaf, the LAI was small, chlorophyll decomposes quickly and these leaves showed the signs of early ageing. The matter accumulation was lower than that of control. Picking bud and fruit made photosynthesis rate of single leaf descend, chlorophyll decomposes slowly and its content keeps high, that inhibited ageing of the plant obviously. The LAI keeps larger, photosynthate was abundant. Dry matter accumulation and distribution to the root were higher than that of control and that of side tress picked. So, the yield with this treatment increased.

CONCLUSIONPicking bud can increase LAI, postpone the decomposition of chlorophyll, and protract the functional leaves. Consequently, picking bud can add the accumulation of dry matter, increase proportion to radix and improve the yield and economy benefit.

Biomass ; Chlorophyll ; metabolism ; Cynanchum ; growth & development ; metabolism ; physiology ; Fruit ; physiology ; Photosynthesis ; physiology ; Plant Leaves ; physiology ; Plant Roots ; metabolism ; physiology ; Plant Shoots ; physiology ; Plants, Medicinal ; growth & development ; metabolism ; physiology

Forest plays very important roles in global system with about 35% land area producing about 70% of total land net production. It is important to consider both elevated CO(2) concentrations and different soil moisture when the possible effects of elevated CO(2) concentration on trees are assessed. In this study, we grew Cinnamomum camphora seedlings under two CO(2) concentrations (350 micromol/mol and 500 micromol/mol) and three soil moisture levels [80%, 60% and 40% FWC (field water capacity)] to focus on the effects of exposure of trees to elevated CO(2) on underground and aboveground plant growth, and its dependence on soil moisture. The results indicated that high CO(2) concentration has no significant effects on shoot height but significantly impacts shoot weight and ratio of shoot weight to height under three soil moisture levels. The response of root growth to CO(2) enrichment is just reversed, there are obvious effects on root length growth, but no effects on root weight growth and ratio of root weight to length. The CO(2) enrichment decreased 20.42%, 32.78%, 20.59% of weight ratio of root to shoot under 40%, 60% and 80% FWC soil water conditions, respectively. And elevated CO(2) concentration significantly increased the water content in aboveground and underground parts. Then we concluded that high CO(2) concentration favours more tree aboveground biomass growth than underground biomass growth under favorable soil water conditions. And CO(2) enrichment enhanced lateral growth of shoot and vertical growth of root. The responses of plants to elevated CO(2) depend on soil water availability, and plants may benefit more from CO(2) enrichment with sufficient water supply.
Biomass ; Carbon Dioxide ; metabolism ; Cinnamomum camphora ; growth & development ; metabolism ; Plant Roots ; growth & development ; metabolism ; Plant Shoots ; growth & development ; metabolism ; Soil ; Trees ; growth & development ; metabolism ; Water ; metabolism