ZmD11 Gene Regulates Tobacco Plant Floral Development under Drought Stress

Maize is most sensitive to drought stress at the floral stage by reducing tassel and silk quality, and thus improving drought tolerance at this stage may help preserve yield. It has been reported that BRs (brassinosteroids) promote floral development under drought stress. However, the function of the brassinosteroid biosynthesis gene ZmDWARF11 (ZmD11) on floral growth under drought stress has not been elucidated. This study found that under normal growth conditions, the heterologous over-expression of ZmD11 significantly enhanced both the vegetative growth and floral develop-ment of tobacco. Under drought stress, overexpressing ZmD11 reduced stress-induced tobacco flower size reduction, while it did not affect vegetative growth. After drought treatment, the activ-ities of protective enzymes, including CAT (Catalase), SOD (Superoxide Dismutase), and POD (Peroxidase), were higher, while the content of MDA (Malondialdehyde) was lower in ZmD11 over-expression tobacco lines than that in the wild type control. The relative expression of dehy-drin-related genes NtLeat5 and NtERD10 was increased in ZmD11 over-expression tobacco lines compared to that in the control. In summary, we reported that ZmD11 plays a role in tobacco floral development under drought stress. Our data are valuable in understanding the functions of BRs in regulating plant floral development under drought stress

Integrating Narcissus-derived galanthamine production into traditional upland farming systems

Alzheimer’s disease (AD) is a disorder associated with progressive degeneration of memory and cognitive function. Galantamine is a licenced treatment for AD but supplies of the plant alkaloid that it is produced from, galanthamine, are limited. This three-year system study tested the potential to combine Narcissus-derived galanthamine production with grassland-based ruminant production. Replicate plots of permanent pasture were prepared with and without bulbs of Narcissus pseudonarcissus sown as lines into the sward. Two different fertiliser regimes were imposed. The above-ground green biomass of N. pseudonarcissus was harvested in early spring and the galanthamine yield determined. In the second harvest year a split-plot design was implemented with lines of N. pseudonarcissus cut annually and biennially. All plots were subsequently grazed by ewes and lambs and animal performance recorded. Incorporation of N. pseudonarcissus into grazed permanent pasture had no detrimental effects on the health or performance of the sheep which subsequently grazed the pasture. There was no consistency to the effects of fertiliser rates on galanthamine yields. There was no difference in overall galanthamine yield if N. pseudonarcissus was cut biennially (1.64 vs. 1.75 kg galanthamine/ha for annual combined vs biennial cuts respectively; s.e.d = 0.117 kg galanthamine/ha; ns). This study verified the feasibility of a dual cropping approach to producing plant-derived galanthamine

Biologically active Amaryllidaceae alkaloids in Narcissus pseudonarcissus cv. Carlton and Andrew’s Choice dormant bulbs

Since the ancient times, Amaryllidaceae genus Narcissus has been reported for the production of biologically important alkaloids, many of which are used as therapeutic tools for human diseases. Among them, galanthamine (Gal) has received a considerable attention for its acetylcholinesterase inhibitory activity for the treatment of early to mid-stage Alzheimer’s diseases. In this study, gas chromatography-mass spectrophotometry was used to determine the galanthamine content along with the detection of other biologically important alkaloids in dormant bulb and basal plate of two cultivated varieties of Narcissus pseudonarcissus, Carlton and Andrew’s Choice. The amount of galanthamine was higher in Carlton bulb (860 µg Gal/g) and basal plate (1254 µg Gal/g) than Andrew’s Choice bulb (674 µg Gal/g) and basal plate (1051 µg Gal/g). Non-dormant Carlton bulb was used as control, which represented the galanthamine content of 1117 µg Gal/g. Besides galanthamine, other biologically important alkaloids were detected in Carlton such as lycoramine, lycorine, lycorenine, crinamine, and pancracine; while tazettine, oxoassoanine, lycorine, and o-methyl-macronine were detected in Andrew’s Choice. Findings of this study suggest that both Narcissus cultivars could be the important sources for the isolation of naturally occurring bioactive alkaloids for their commercial availability and could be potentially used in pharmaceuticals

Preparation and Device Applications of Ferroelectric β-PVDF Films

Organic ferroelectric materials have unique characters comparing to their inorganic counterparts in electronics because they show the advantages such as low cost, lightweight, small thermal budget, flexible and nontoxic characteristics. The ferroelectric poly(vinylidene fluoride) (PVDF) is mostly desired for memory devices due to its polar phase. To obtain the ferroelectric memory devices for data storage, ultrathin PVDF films are required to allow for low operation voltages with both small roughness and free of pin-holes. Micron-meter thick films of ferroelectric phase PVDF can be easily achieved by many preparation methods. But the nanofilms could be mainly fabricated by coating method and Langmuir–Blodgett deposition technique. Meanwhile, according to the structure of devices, four types of organic memory cells using ferroelectric phase PVDF films were introduced, such as memory based on metal/organic semiconductor/metal ferroelectric tunnel junctions, organic capacitors, field effect transistor and organic diodes. The research has been mainly done in Zhang’s laboratory from September 2016 to explore the preparation and potential applications of ferroelectric PVDF films. In this chapter, we summarize several device investigations and show the PVDF films have the promising memory applications

Metabolomics reveals the response of hydroprimed maize to mitigate the impact of soil salinization

Soil salinization is a major environmental stressor hindering global crop production. Hydropriming has emerged as a promising approach to reduce salt stress and enhance crop yields on salinized land. However, a better mechanisitic understanding is required to improve salt stress tolerance. We used a biochemical and metabolomics approach to study the effect of salt stress of hydroprimed maize to identify the types and variation of differentially accumulated metabolites. Here we show that hydropriming significantly increased catalase (CAT) activity, soluble sugar and proline content, decreased superoxide dismutase (SOD) activity and peroxide (H2O2) content. Conversely, hydropriming had no significant effect on POD activity, soluble protein and MDA content under salt stress. The Metabolite analysis indicated that salt stress significantly increased the content of 1278 metabolites and decreased the content of 1044 metabolites. Ethisterone (progesterone) was the most important metabolite produced in the roots of unprimed samples in response to salt s tress. Pathway enrichment analysis indicated that flavone and flavonol biosynthesis, which relate to scavenging reactive oxygen species (ROS), was the most significant metabolic pathway related to salt stress. Hydropriming significantly increased the content of 873 metabolites and significantly decreased the content of 1313 metabolites. 5-Methyltetrahydrofolate, a methyl donor for methionine, was the most important metabolite produced in the roots of hydroprimed samples in response to salt stress. Plant growth regulator, such as melatonin, gibberellin A8, estrone, abscisic acid and brassinolide involved in both treatment. Our results not only verify the roles of key metabolites in resisting salt stress, but also further evidence that flavone and flavonol biosynthesis and plant growth regulator relate to salt tolerance

Metabolomics reveals the response of hydroprimed maize to mitigate the impact of soil salinization

Soil salinization is a major environmental stressor hindering global crop production. Hydropriming has emerged as a promising approach to reduce salt stress and enhance crop yields on salinized land. However, a better mechanisitic understanding is required to improve salt stress tolerance. We used a biochemical and metabolomics approach to study the effect of salt stress of hydroprimed maize to identify the types and variation of differentially accumulated metabolites. Here we show that hydropriming significantly increased catalase (CAT) activity, soluble sugar and proline content, decreased superoxide dismutase (SOD) activity and peroxide (H2O2) content. Conversely, hydropriming had no significant effect on POD activity, soluble protein and MDA content under salt stress. The Metabolite analysis indicated that salt stress significantly increased the content of 1278 metabolites and decreased the content of 1044 metabolites. Ethisterone (progesterone) was the most important metabolite produced in the roots of unprimed samples in response to salt s tress. Pathway enrichment analysis indicated that flavone and flavonol biosynthesis, which relate to scavenging reactive oxygen species (ROS), was the most significant metabolic pathway related to salt stress. Hydropriming significantly increased the content of 873 metabolites and significantly decreased the content of 1313 metabolites. 5-Methyltetrahydrofolate, a methyl donor for methionine, was the most important metabolite produced in the roots of hydroprimed samples in response to salt stress. Plant growth regulator, such as melatonin, gibberellin A8, estrone, abscisic acid and brassinolide involved in both treatment. Our results not only verify the roles of key metabolites in resisting salt stress, but also further evidence that flavone and flavonol biosynthesis and plant growth regulator relate to salt tolerance

Effect of light and temperature on volatile compounds and growth parameters in sweet basil (Ocimum basilicum L.)

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