Identification and expression analysis of the KNOX genes during organogenesis and stress responseness in Camellia sinensis (L.) O. Kuntze.

Tea plant (Camellia sinensis L.), whose leaves are the major reproductive organs, has been cultivated and consumed widely for its economic and health benefits. The Knotted1-like Homeobox (KNOX) proteins play significant roles in leaf morphology formation and development. However, the functions of KNOX proteins in tea plants are still unknown. Here, 11 CsKNOX genes from the tea plants were cloned and divided into Class I, II, and KNATM clades based on their protein sequences. These 11 CsKNOX genes were mapped on 8 out of 15 tea plant chromosomes, all localized in the nucleus. Specific spatiotemporal expression patterns of CsKNOX genes were found in various tissues and different development periods of buds, flowers, and roots of tea plants. Meanwhile, transcript levels of CsKNOX in tea leaves were strongly correlated with the accumulation of flavan-3-ols and proanthocyanidins. It was found that most of the CsKNOX genes could respond to drought, salt, cold, and exogenous MeJA and GA3 by analysis of transcriptomics data and promoter elements. The protein interaction analysis showed that CsKNOX could cooperate with CsAS1 and other critical functional proteins. In conclusion, this research provided the basic information for the functions of the CsKNOX family during organogenesis and stress response in tea plants, which was necessary for further functional characterization verification.

Identification and characterization of homeobox gene clusters in harpacticoid and calanoid copepods.

In this study, we have identified the entire complement of typical homeobox (Hox) genes (Lab, Pb, Dfd, Scr, Antp, Ubx, Abd-A, and Abd-B) in harpacticoid and calanoid copepods and compared them with the cyclopoid copepod Paracyclopina nana. The harpacticoid copepods Tigriopus japonicus and Tigriopus kingsejongensis have seven Hox genes (Lab, Dfd, Scr, Antp, Ubx, Abd-A, and Abd-B) and the Pb and Ftz genes are also present in the cyclopoid copepod P. nana. In the Hox gene cluster of the calanoid copepod Eurytemora affinis, all the Hox genes were present linearly in the genome but the Antp gene was duplicated. Of the three representative copepods, the P. nana Hox gene cluster was the most compact due to its small genome size. The Hox gene expression profile patterns in the three representative copepods were stage-specific. The Lab, Dfd, Scr, Pb, Ftz, and Hox3 genes showed a high expression in early developmental stages but Antp, Ubx, Abd-A, and Abd-B genes were mostly expressed in later developmental stages, implying that these Hox genes may be closely associated with the development of segment identity during early development.

Impedance flow cytometry allows the early prediction of embryo yields in wheat (Triticum aestivum L.) microspore cultures.

Haplomethods are key biotechnological tools that make it possible to rapidly produce perfectly homozygous lines, speeding up plant breeding programs. Under specific stress conditions, microspores are reprogrammed toward sporophytic pathways, leading to embryo formation. Various endogenous and exogenous factors affect embryo yield in androgenesis, so the improvement of androgenesis efficiency requires the development of early, reliable and robust reactivity markers. During the last decade, numerous cytological, cellular and biochemical approaches were carried out to finely characterize microspore development and fate during androgenesis. However, the different available markers are often species-dependent, and their development and application are time-consuming and cumbersome. In this study, we show the suitable use of impedance flow cytometry (IFC) to develop new robust, reliable and strong markers of androgenesis reactivity in wheat, leading to: (i) routine monitoring of the viability of heterogeneous cell cultures; (ii) quick and simple evaluation of stress treatment efficiency; and (iii) early prediction of embryo yields from microspore suspensions. IFC can therefore provide the fine characterization of all of the microspore developmental pathways that occur in a cell suspension, for embryogenic microspores as well as pollen-like microspores. IFC technology has become a very useful tool to track and characterize wheat microspores in androgenesis, but can also be adapted to other species and other in vitro cell culture systems.

Evaluation of Phytochemical Compositions and Biological Properties of Achillea gypsicola at Different Phenological Stages.

Phytochemicals, which are commonly found at different levels in many medicinal plants, are natural strong antioxidants used in traditional medicine. In this research, determination of differences of phytochemical compositions and biological properties were aimed as periodically (pre-, full and post flowering) and daily (6 am, 1 pm and 8 pm) in Achillea gypsicola Hub.-Mor. The volatile oils belonging to A. gypsicola were obtained by hydrodistillation and analyzed by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC/MS). The antimicrobial activities of the volatile oils were determined with disc diffusion method. The microdilution method was used to determine minimum inhibitory concentration (MIC). Total phenolic and flavonoid contents were determined by spectrophotometric methods and antioxidant capacities were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical, reducing power (RP) and metal chelating activity (MCA) assay. In addition, the phenolic acid and flavonoid compositions were evaluated by reversed phase-high-performance liquid chromatography (RP-HPLC). This study presented a comprehensive report for the first time on evaluation of the phytochemical composition and the biological properties of A. gypsicola at different phenological stages. Thirty-two compounds, containing the major component as camphor, 1,8-cineole and borneol, were detected. Designated harvest time for the highest yield of volatile oils was found to be at full flowering stage-1 pm. It has been observed that the volatile oil composition changes periodically and even daily. Also, in this research, menthol and menthone were found as the composition of volatile oil in Achillea species for the first time. Full flowering stage was found as the richest period in terms of phenolic acid and flavonoid compositions of A. gypsicola for the first time. The species examined in this research showed a high antioxidant and antimicrobial activity in comparison to other studies with Achillea species. The volatile oils exhibited high performances with range of inhibition zones (8.3-42.3 mm) and minimum inhibitory concentration values (2.25-144 µg/ml). Besides, a high correlation between antioxidant activity and phenolic content of A. gypsicola was found. These results suggest that A. gypsicola can be used as a safe source in the cosmetic, food and pharmaceutical industries.

Fennel (Foeniculum vulgare Mill. subsp. piperitum) florets, a traditional culinary spice in Italy: evaluation of phenolics and volatiles in local populations, and comparison with the composition of other plant parts.

BACKGROUND: Wild fennel (Foeniculum vulgare Mill. subsp. piperitum) florets are used as a typical spice in central and southern Italy. Although fennel (Foeniculum vulgare Mill.), belonging to the Apiaceae (syn. Umbelliferae) family, is a well-known vegetable and aromatic plant, whose main phytochemical compounds have been extensively analysed and investigated as flavouring agents and for their putative health promoting functions, its florets have not been specifically considered up to now. Therefore, the volatile and phenolic composition of florets from an Italian wild fennel crop was determined at different developmental stages, and compared to that of leaves and fruits. Moreover, florets of nine Italian wild fennel populations of different geographical origin from northern-central Italy were also analysed. RESULTS: The total phenolic amount increased from leaves to florets, reaching its highest value in early florets, at 58 012 mg kg-1 of dry matter (DM), then constantly decreased in fruits. In florets of wild populations, phenolics ranged from 6666 to 43 368 mg kg-1 DM. The total amount of volatile compounds was more than twice higher in florets (21 449 mg kg-1 DM) than in leaves (10 470 mg kg-1 DM), reaching its highest value in fruits (50 533 mg kg-1 DM). Estragole and trans-anethole were the main compounds of the volatile fraction. Total volatiles ranged from 24 367 to 60 468 mg kg-1 DM in florets of local populations. CONCLUSION: Significant changes in the total amount and profile of both phenolic and volatile compounds occurred during plant development. The consistent increase of estragole at later developmental stages supported the claim of different sensory properties of florets and fruits. Geographical origin significantly affected phenolic and volatile composition of wild fennel florets. © 2017 Society of Chemical Industry.

Reproductive organ and young tissues show constrained elemental composition in Arabidopsis thaliana.

BACKGROUND AND AIMS: The identification of stoichiometric homeostasis is crucial for understanding plant adaptive strategies under a changing environment. However, current knowledge of plant stoichiometric homeostasis has mainly been obtained from mature leaves, with little from other organs across different developmental stages. METHODS: We conducted a greenhouse nitrogen (N) and phosphorus (P) addition experiment to evaluate the strength of stoichiometric homeostasis across different organs and developmental stages of Arabidopsis thaliana. KEY RESULTS: Homeostatic regulation coefficients (H) for N (HN), P (HP) and N : P ratio (HNP) were highest in reproductive tissue, followed by stem and leaf at the same stage. All H parameters in the same organ decreased significantly over the developmental stages. Leaf HN, HP and HNP were highest at stage 1, followed by stages 2 and 3. Both stem and silique at stage 2 relative to stage 3 had higher HN, HP and HNP. These results suggested that reproductive tissue relative to other organs and young tissue relative to old tissue showed more constrained elemental composition in response to nutrient availabilities, and such trends were also evidenced by stoichiometric scaling relationships. CONCLUSIONS: Our findings highlight that stoichiometric homeostasis is tightly related to the ontogenesis of plant tissue. These results could have a strong implication for diagnosing relative availabilities of N and P in ecosystems, suggesting that the N and P stoichiometry of old tissues might be stronger indicators of nutrient status for plants, but further study is needed to test the generality across species with more distinguishable functional traits.

Life cycle stage and water depth affect flooding-induced adventitious root formation in the terrestrial species Solanum dulcamara.

BACKGROUND AND AIMS: Flooding can occur at any stage of the life cycle of a plant, but often adaptive responses of plants are only studied at a single developmental stage. It may be anticipated that juvenile plants may respond differently from mature plants, as the amount of stored resources may differ and morphological changes can be constrained. Moreover, different water depths may require different strategies to cope with the flooding stress, the expression of which may also depend on developmental stage. This study investigated whether flooding-induced adventitious root formation and plant growth were affected by flooding depth in Solanum dulcamara plants at different developmental stages. METHODS: Juvenile plants without pre-formed adventitious root primordia and mature plants with primordia were subjected to shallow flooding or deep flooding for 5 weeks. Plant growth and the timing of adventitious root formation were monitored during the flooding treatments. KEY RESULTS: Adventitious root formation in response to shallow flooding was significantly constrained in juvenile S. dulcamara plants compared with mature plants, and was delayed by deep flooding compared with shallow flooding. Complete submergence suppressed adventitious root formation until up to 2 weeks after shoots restored contact with the atmosphere. Independent of developmental stage, a strong positive correlation was found between adventitious root formation and total biomass accumulation during shallow flooding. CONCLUSIONS: The potential to deploy an escape strategy (i.e. adventitious root formation) may change throughout a plant's life cycle, and is largely dependent on flooding depth. Adaptive responses at a given stage of the life cycle thus do not necessarily predict how the plant responds to flooding in another growth stage. As variation in adventitious root formation also correlates with finally attained biomass, this variation may form the basis for variation in resistance to shallow flooding among plants.

Seasonal variability of the main components in essential oil of Mentha × piperita L.

BACKGROUND: Mentha × piperita is an important and commonly used flavoring plant worldwide. Its constituents, primarily menthol and menthone, change in the essential oil depending on internal and external factors, of which environmental conditions appear very important. The experiment was established in 2010 for three vegetation season, in order to observe the quantitative changes of the main components of peppermint. The determination of menthol, menthone, limonene, menthyl acetate, menthofuran and ß-caryophyllene was registered. RESULTS: In the experimental season 2011 and 2012 a higher mean temperature than in 2010 and extreme rainfall in July 2011 and 2012 were recorded. Different environmental conditions affected the development of M. × piperita plants and the content and composition of the essential oil. CONCLUSION: Seasonal and maturity variations are interlinked with each other, because the specific ontogenic growth stage differed as the season progressed. Fluctuations in monthly and seasonal temperature and precipitation patterns affected the quality of peppermint essential oil.

The hazardous effects of three natural food dyes on developmental stages and longevity of Drosophila melanogaster.

Nowadays, food dyes obtained from herbal, animal, microbial and mineral sources are widely used as food additives. In this study, the toxic effects of three different natural food dyes (carmine, turmeric and annatto) on 72 ± 4 h larvae of Oregon-R wild type of Drosophila melanogaster were investigated. For this purpose, four different application doses (50, 75, 100, 125 mg mL(-1)) were chosen by means of preliminary studies. It was determined that larval mortality increased with increasing concentration in the application groups and the toxicity order was carmine > turmeric > annatto. It was observed that the survival rate was highest in the control with 98% and lowest in 125 mg mL(-1) carmine with 16%. In addition, the average lifespan of the adult individuals obtained from third instar larvae was also studied. While the average lifespan was 40.88 ± 1.44 days in the control group, these values were 10.81 ± 0.55-23.90 ± 1.27 days in the carmine group, 15.00 ± 0.80-22.42 ± 1.43 days in the turmeric group and 10.33 ± 1.03-35.68 ± 1.54 days in the annatto group, respectively. According to the obtained results, when both the developmental period from larvae into adults and the lifespan of the developing adults were compared with the control group, the food dyes were found to be toxic and the toxicity order of carmine > turmeric > annatto was identified.

Comparative Study of Anti-oxidative Effects of Tibetan Folk Medicine Erigeron multiradiatus during Plant Growth / 中草药·英文版

Objective To explore the effects of a potential anti-oxidative plant,Erigeron multiradiatus(Asteraceae),plant materials from naturally distributed high-altitude populations at different stages of life cycle were collected.Methods Fifteen extracts obtained from the Ganzi region(Sichuan,China)were studied to assess their radical-scavenging ability on 1,1-diphenyl-2-picrylhydrazyl radicals and reducing power ability.Moreover,considering that anti-oxidants and free radical scavengers can also exert protective effect on endothelial cells from oxidative injury,these extracts were also evaluated for their anti-oxidative activity against cellular injury in the cultured human endothelial cell line(ECV304)induced by hydrogen peroxide(HO).Results All the extracts had radical-scavenging and/or reducing power ability,and the most active extract was found during flowering whereas the lowest appeared during vegetative growth period.The accumulation of anti-oxidative compounds was found to be affected by the altitude of growth environment.Total flavonoid content assay was also performed to support this outcome.Furthermore,these extracts also exhibited different effects on attenuating HO-induced cytotoxicity and inhibiting lipid peroxidation and LDH leakage from endothelial cells.Conclusion E.multiradiatus may be an important natural anti-oxidant and this property may contribute to verifying the utilization of this plant in Tibet folk medicine.

High frequency of plant regeneration in sunflower from cotyledons via somatic embryogenesis.

A plant regeneration methodvia somatic embryogenesis of severalHelianthus annuus L. genotypes was developed. Starting from cotyledonary explants high frequency embryo induction was obtained following several subcultures on defined media. An appropriate cotyledon developmental stage was identified. Etiolated explants and darkness treatment were necessary to obtain somatic embryos in all tested genotypes. After 20-25 days on somatic induction medium containing an auxin:cytokinin ratio of 1:1, the germination of embryos was induced by a reduction of the hormonal ratio (1:2). Shoots were excised from callus and transferred onto a medium containing various vitamins. The range of embryogenesis frequency was 33-72%, depending on the genotype. High frequency of rooting (49-82%) was obtained using a medium supplemented with 0.5 mg/L of ancymidol and by a reduction of photoperiod. A large percentage of somatic embryos developed into normal regenerated plants producing viable seeds.