Half Of Leaf Research Articles

Spiral Mechanism in <i>Arenga pinnata</i>

The phyllotaxy of Arenga pinnata is alternate and cyclic revealing two distinct foliar spirals. In some individuals, the two spirals veer to the left and in others, to the right. The number of leaflets on one half of leaf differs from that of the other. This difference is associated with the leaf spirals. Due to the monocarpic nature of the palm, its reproductive phase starts with a terminal inflorescence followed by the development of axillary inflorescences in basipetal order. The sex of the flowers varies with the position of the respective spadices on the palm. That is, the terminal and a few immediate successive spadices produce only female flowers, beyond which each inflorescence produces both female and male flowers, and the last many spadices have only males. The flowers are distributed in clusters of 2 males or 2 males and a female in between, or individually if they are only females. In a cluster of 2 or 3 flowers, The aestivation of sepals of the males varies with their position in the triad. The aestivation pattern in female flowers, however, has an influence on the spirality of the spika on which they are borne.

Detection of QTLs controlling flowering in a cross-pollinated F1 population of Miscanthus sinensis

Miscanthus is a perennial rhizomatous grass belonging to Andropogoneae, which is now used as lignocellulosic biomass crop. Miscanthus has a short history of domestication, so further breeding effort for improved biomass production is needed. Flowering plays a critical role in controlling vegetative growth and physiology of plant, so this study focused on finding quantitative trait locus controlling flowering of Miscanthus for use in marker assisted breeding. A cross-pollinated M. sinensis F1 population consisted of 278 progenies was produced, transplanted to the field and assessed in their flowering traits. Julian dates of flag leaf extension, first heading, half heading, first flowering, and half flowering were assessed in 2019, the third year after transplanting when Miscanthus was well established. The average Julian dates of the flowering traits were 198±9, 224±14, 233±14, 239±15 and 253±12, respectively, and showed a proximal normal distribution. Genotype by sequencing conducted by Illumina-hiseq using leaf DNA samples revealed the genetic map consisted of 1988 SNPs with average distance of 1.35 cM. Nine QTLs controlling flowering were detected exceeded 60% of LOD score threshold. These QTLs were neighboring 16 SNP markers, 5 of which were contained in known functional genes including RGL2 (gibberellin pathway regulation). Genetic map and marker information acquired through this study, including either annotated or not annotated markers, are expected to help understand and help breeding new Miscanthus in the future with desired flowering.

Design, synthesis, and bioactivity studies of chalcone derivatives containing [1,2,4]-triazole-[4,3-a]-pyridine

In this study, 30 chalcone derivatives containing [1,2,4]-triazole-[4,3-a]-pyridine were designed and synthesized. The results of antibacterial activity showed that EC50 values of N26 against Xoo, Pcb was 36.41, 38.53 μg/mL, respectively, which were better than those of thiodiazole copper, whose EC50 values were 60.62, 106.75 μg/mL, respectively. The bacterial inhibitory activity of N26 against Xoo was verified by SEM. Antibacterial mechanism between N26 and Xoo was preliminarily explored, the experimental results showed that when the drug concentration was 100 mg/L, N26 had a good cell membrane permeability of Xoo, and it can inhibit the production of EPS content and extracellular enzyme content to disrupt the integrity of the Xoo biofilms achieving the effect of inhibiting Xoo. At 200 mg/L, N26 can protect and inhibit the lesions of post-harvested potatoes in vivo. The activities of N1-N30 against TMV were determined with half leaf dry spot method. The EC50 values of the curative and protective activity of N22 was 77.64 and 81.55 μg/mL, respectively, which were superior to those of NNM (294.27, 175.88 μg/mL, respectively). MST experiments demonstrated that N22 (Kd = 0.0076 ± 0.0007 μmol/L) had a stronger binding ability with TMV-CP, which was much higher than that of NNM (Kd = 0.7372 ± 0.2138 μmol/L). Molecular docking results showed that N22 had a significantly higher affinity with TMV-CP than NNM.

Design, synthesis, antibacterial and antiviral evaluation of chalcone derivatives containing benzoxazole

In this study, 24 chalcone derivatives containing benzoxazole were designed and synthesized, and the structures of all target compounds were confirmed by NMR and HRMS. The results of antibacterial activity showed that the median effective concentration (EC50) value of Z2 against Xanthomonas oryzae pv.oryzae (Xoo) was 8.10 μg/mL, which was better than thiodiazole copper (60.62 μg/mL), the antibacterial activity of Z2 was verified by scanning electron microscopy (SEM). Antibacterial mechanism of Z2 on Xoo was preliminarily explored, and the results showed concentrations were 100, 50 mg/L, which had a good cell membrane permeability to Xoo and can inhibit the EPS content and the production of extracellular enzymes, affecting the formation of biofilm, preliminary validation of the antibacterial effect of Z2 on Xoo. At 200 mg/L, Z2 had a better protective activity on harvested potatoes, which was comparable with thiodiazole copper. The activity against tobacco mosaic virus (TMV) was determined with half leaf dry spot method. The EC50 value of curative activity of Z15 was 101.97 μg/mL, which was superior to ningnanmycin (NNM) 294.27 μg/mL, and the EC50 value of protective activity of Z16 was 104.05 μg/mL, which was superior to NNM 185.73 μg/mL. Molecular docking results showed Z15, Z16 had a significantly higher affinity with tobacco mosaic virus coat protein (TMV-CP) than NNM. The above results indicated that chalcone derivatives containing benzoxazole have the potential to become antibacterial and antivirial agents.

An Intriguing Half Leaf from the Middle Jurassic of China

An Intriguing Half Leaf from the Middle Jurassic of China

Флуктуирующая асимметрия листьев рябины обыкновенной (Sorbus aucuparia L.) как биоиндикатор аэротехногенного загрязнения города Оренбурга

An assessment of environmental pollution in the city of Orenburg was conducted using the fluctuating asymmetry method. The common mountain ash was chosen as an environ­mental indicator. Leaf collection took place at seven points in the city with varying anthropo­genic loads. The research aimed to determine the impact of aerotechnogenic pollution on the magnitude of the fluctuating asymmetry of the leaf blade of the populations of mountain ash within the city of Orenburg. The study revealed that the leaf blades of mountain ash in urban conditions are affected by anthropogenic factors, experiencing air pollution and accumulating harmful substances. The fluctuating asymmetry method can be used as an indicator of plant development instability in urban ecosystems. Elevated environmental stress, based on the integral indicator of fluctuating asymmetry, was noted at all points except the Ural River Embankment. In this area, the growing conditions for plants were characterized as satisfacto­ry. Through pairwise correlation analysis of the examined characteristics, the closest connec­tions were found between two pairs: the width of the leaf half — the distance between the ba­ses of the first and second order veins; the distance from the base of the leaf plate to the end of the second-order vein — the angle between the main vein and the second from the base of the leaf.

TiO2 nanoparticle synthesis, characterization and application to shoot regeneration of water hyssop (Bacopa monnieri L. Pennel) in vitro

ABSTRACT Water hyssop (Bacopa monnieri L. Pennel) is a medicinal aquatic herb used to treat diseases in South Asia. Various regeneration protocols have been developed or modified in vitro to ensure the availability of biomass and secondary metabolites of Bacopa. We applied hydrothermally treated titanium dioxide (TiO2) nanoparticles (NPs) (TiO2-NPs) at different concentrations. Three explants, distal portion of half leaf (DPHL), proximal portion of half leaf (PPHL) and full leaf (FL), were used to evaluate response to TiO2. Regeneration from the three explants in vitro was similar except for shoot length. Application of TiO2-NPs exerted significant, but variable, effects on all parameters except percentage of shoot formation, which was 100%. Interactive effects of explant and TiO2-NPs exhibited significant, but variable, effects on fresh weight and percentage of callus formation. All explants produced more shoots using TiO2-NPs compared to control treatments. DPHL explants with application of 8 mg/l TiO2 produced more shoots than controls. Similarly, FL explant treated with 2 mg/l TiO2-NPs produced more shoots/explant than controls. All concentrations of TiO2-NPs produced significantly longer shoots compared to controls. Increased elongation of shoots justifies use of TiO2-NPs for propagation of plants in vitro during acclimatization. Use of TiO2-NPs for rapid elongation of shoots ultimately fosters survival of plants.

Effect of the simulated half leaf width of a multileaf collimator on volumetric modulated arc therapy plan quality in hippocampal avoidance whole-brain radiotherapy.

PurposeWhole‐brain radiotherapy (WBRT) is commonly used in patients with multiple brain metastases. Compared with conventional WBRT, hippocampal avoidance WBRT (HA‐WBRT) more favorably preserves cognitive function and the quality of life. The hippocampal volume is considerably small (approximately 3.3 cm3). Therefore, downsizing the leaf width of a multileaf collimator (MLC) may provide higher spatial resolution and better plan quality. Volumetric modulated arc therapy (VMAT) could simulate the half MLC leaf width through couch shifting between arcs. This study investigated changes in VMAT quality for HA‐WBRT with a simulated fine MLC leaf width.MethodsWe included 18 patients with brain metastasis. All target and avoidance structures were contoured by an experienced radiation oncologist. The prescribed dose was 30 Gy in 10 fractions. For each patient, three different treatment plans were generated for comparison: VMAT with couch‐shift, VMAT without couch‐shift, and TomoTherapy. All treatment plans fulfilled Radiation Therapy Oncology Group (RTOG) 0933 criteria for HA‐WBRT. The Wilcoxon paired signed‐rank test was used to compare different treatment plans.ResultsVMAT with couch‐shift had the better average conformity index (0.823) with statistically significant difference compared to VMAT without couch‐shift (0.810). VMAT with couch‐shift (0.219) had a more favorable average homogeneity index (HI) than did VMAT without couch‐shift (0.230), although the difference was not significant. TomoTherapy had an optimal average HI of 0.070. In terms of the hippocampus, all three treatment plans met the RTOG 0933 criteria. VMAT with couch‐shift had a lower average D max (15.2 Gy) than did VMAT without couch‐shift (15.3 Gy, p = 0.071) and TomoTherapy (15.5 Gy, p = 0.133). The average D 100% of hippocampus was the same for both VMAT with and without couch‐shift (8.5 Gy); however, TomoTherapy had a lower average D 100% value of 7.9 Gy. The treatment delivery time was similar between VMAT with and without couch‐shift (average, 375.0 and 369.6 s, respectively). TomoTherapy required a long average delivery time of 1489.9 s.ConclusionThe plan quality of VMAT for HA‐WBRT was improved by using the couch‐shift technique to simulate the half MLC leaf width. However, the improvement was not statistically significant except conformity index. The downsizing effect decreased with the use of the sophisticated grade of VMAT. TomoTherapy offered superior plan quality but required the longest delivery time.

Mechanical characterization and static analysis of fiber based hybrid composite multi leaf spring

This work is to examine the possibility of utilizing a base expense and light weight materials for auto leaf spring suspension application. We contrast existing steel 65Si7 leaf spring and half and half composite leaf spring, for example, Epoxy/E- Glass/Viscose staple fiber (40%:45%:15%) in light of the disfigurement, flexibility, determination, strain energy putting away limit, cost viability and weight minimises. Static examination has been performed to consider the advantages of half and half composite materials for leaf spring suspension models in auto industry and results shows that Epoxy/E-Glass/Viscose staple fiber is the awesome the excess creation. Utilization of Epoxy/E-Glass/Viscose staple fiber (40%:45%:15%) prompts 76.37%weight decrease in leaf spring when contrasted with existing steel 65Si7 leaf spring.

Synthesis of Novel Antiviral Ferulic Acid-Eugenol and Isoeugenol Hybrids Using Various Link Reactions.

To develop novel antiviral agents, some novel conjugates between ferulic acid and eugenol or isoeugenol were designed and synthesized by the link reaction. The antiviral activities of compounds were evaluated using the half leaf dead spot method. Bioassay results showed acceptable antiviral activities of some conjugates against the tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV). Compounds A9, A10, E1, and E4 showed remarkable curative, protective, and inactivating effects on TMV and CMV at 500 μg mL-1. Notably, these compounds exhibited excellent protective effects on TMV and CMV. The EC50 values of compounds A9, A10, E1, and E4 against TMV were 180.5, 169.5, 211.4, and 135.5 μg mL-1, respectively, and those against CMV were 210.5, 239.1, 218.4, and 178.6 μg mL-1, respectively, which were superior to those of ferulic acid (471.5 and 489.2 μg mL-1), eugenol (456.3 and 463.2 μg mL-1), isoeugenol (478.4 and 487.5 μg mL-1), and ningnanmycin (246.5 and 286.6 μg mL-1). Then, the antiviral mechanisms of compound E4 were investigated by determining defensive enzyme activities and multi-omics analysis. The results indicated that compound E4 resisted the virus infection by enhancing defensive responses via inducing the accumulation of secondary metabolites from the phenylpropanoid biosynthesis pathway in tobacco.

Development of critical nitrogen dilution curves for different leaf layers within the rice canopy

Understanding the effect of nitrogen (N) vertical distribution within the rice canopy at different growth stages and development of critical nitrogen dilution curves for upper leaf layers will not only help accurate estimations of the spatial and temporal variation in N status, but will also provide a basis for analyses of N nutrition in rice. Based on a three-year field experiment with 2 rice varieties, 3 N levels and 4 planting densities, the effect of heterogeneity in N vertical distribution on the nitrogen nutrition index (NNI) was then determined, and for the first time, critical N dilution curves of upper leaf layers were constructed based on a Bayesian statistical model. The relationship for NNI entire canopy and its relationship with the other tested leaf layers was investigated. The leaf layer suitable for analyses of N nutrition and directly inversion of NNI by remote sensing is determined. The results revealed that the main contributor to plant N concentration (PNC) of entire canopy (PNCCanopy) was found to be the lower leaf layer of the rice canopy, and may lead to misdiagnosis under the non-N-limiting condition by using the canopy level based NNI. The PNC of top half leaf layer of the canopy was more stable in terms of short-term environmental changes, and more accurately representing the overall N status. The top half leaf layer was the main contributor to canopy reflectance. Thus, compared with the NNI of other upper leaf layers, the NNI of the top half leaf layer is more suitable for direct inversion by using CI (1113, 743) with the R2 = 0.70. Overall, these findings suggest that the NNI of the top half leaf layer is the optimal remote sensing indicator of N nutrition in rice.

Optimizing plant regeneration and genetic transformation of Paulownia elongata

The effects of plant tissue culture media with varying levels of growth regulators and carbon sources was tested on four explant types for organogenesis and plant regeneration in Paulownia elongata. Among the various treatments applied, the best response to adventitious shoot proliferation was observed when entire leaf or half leaf with attached petiole explants were cultured on either MS or B5 medium along with 25 μM thidiazuron, 10 μM indole acetic acid and 30 g L−1 maltose as a carbon source. Proliferated shoots were rooted within five days on a modified MS medium containing 5 μM indole butyric acid and plants were successfully acclimated and hardened for greenhouse transfer. A green fluorescent protein (gfp) and neomycin phosphotransferase II (npt II) gene was used to optimize genetic transformation protocols. Agrobacterium tumefaciens mediated transformation of half leaf with petiole explants produced transgenic plants using the media optimized for shoot proliferation and rooting. The insertion and expression of the GFP transgene was detected using PCR and RT-PCR.

On the Full- and Half-Sheet Inserts of Andreas Vesalius’s De humani corporis fabrica (1543 and 1555)

On the Full- and Half-Sheet Inserts of Andreas Vesalius’s <i>De humani corporis fabrica</i> (1543 and 1555)

Optimization of Micropropagation and Genetic Transformation Protocols for Paulownia elongata : A Short Rotation Fast Growing Bioenergy Tree.

Various steps of micropropagation include selection of suitable explant, establishment of adventitious shoot induction cultures, proliferation, rooting, and acclimatization of the resulting plantlets. A systematic protocol is provided for the micropropagation and Agrobacterium tumefaciens-mediated genetic transformation of a fast growing, multipurpose tree, Paulownia elongata. Our studies show that optimum shoot induction is on half leaf with petiole explant on MS medium supplemented with 25μM thidiazuron and 10μM indole-3 acetic acid. Micropropagation protocols provided here are applicable to explants collected from the primed in vitro raised seedlings on MS medium containing 2.5μM 6-benzylaminopurine (BAP) or actively growing shoots collected from greenhouse or field growing plants. We also discuss a possible role of "Python" script guided protocol optimization for higher and consistent multiplication of shoots that can be very helpful for scaled up production in commercial settings. To facilitate future plant improvement and gene editing possibilities, an A. tumefaciens based genetic transformation protocol and molecular identification of transgenic plants using Polymerase Chain Reaction (PCR) and Reverse Transcriptase-PCR (RT-PCR) techniques have also been optimized.

Propagation of Piper carniconnectivum through leaf cuttings

The regeneration of roots and shoots through leaf cuttings is a feasible technique for plant clonal propagation, using a quite available organ, which can be collected without great damage to the plant. A protocol of propagation through leaf cuttings was defined to Piper carniconnectivum, a plant whose compounds have great potential use in medicine and agriculture. Leaves were cut in halves (apical and petiolar) by transverse cutting in the middle of the leaf blade. The petiolar parts were immersed into a solution of indole 3-butyric acid (IBA) at 1000 ppm for 30 seconds, or not submitted to the hormone. Then the cuttings were planted in soil, using two positions of the petiolar halves: petiole down and petiole up. A factorial design was used – 2 times of immersion in IBA x 2 leaf half position x 3 blocs x 6 replications. After 145 days the number of shoots, shoot length, leaf area, dry matter of aerial part, root volume and root dry matter were evaluated. The highest number of shoots was observed in the petiole down position without IBA. In relation to the other aerial characteristics – shoot length, leaf area and dry matter of the aerial part, the highest values were observed both in the petiole down position without IBA and in the petiole up position with immersion in IBA. The characteristics related to the root – root volume and root dry matter were both highest in the petiole up position with immersion in IBA. Leaf cuttings can be a practical method to propagate P. carniconnectivum vegetatively. Both petiole up cutting with immersion in IBA and petiole down cutting without immersion in hormone can be used as propagules.

Disease Control Attributes of Oxathiapiprolin Fungicides for Management of Cucurbit Downy Mildew.

Oxathiapiprolin, a novel oomycete fungicide recently registered by DuPont, was reported to have high intrinsic activity against cucurbit downy mildew (Pseudoperonospora cubensis). The goal of this study was to characterize disease control attributes of oxathiapiprolin-based fungicides critical to effective management of cucurbit downy mildew. In growth chamber and greenhouse studies, oxathiapiprolin-based fungicides were compared with mandipropamid, mefenoxam + mancozeb, fluopicolide + propamocarb, cymoxanil + mancozeb, and ametoctradin + dimethomorph products for pre- and postinfection activity, local systemic movement, and protection of new growth produced after fungicide application. In preventive application, oxathiapiprolin-based fungicides significantly (P < 0.0001) inhibited downy mildew development, with the highest level of disease observed being 0.4% compared with 86.7% observed for mandipropamid. When applied postinfection, oxathiapiprolin-based fungicides significantly (P < 0.0001) suppressed disease development, but disease control was reduced relative to that observed for preventive application. There was a significant effect of formulation on the postinfection activity of oxathiapiprolin, whereby the oil dispersion (OD) formulation was more inhibitory than the water-dispersible granule formulation (0.001 ≤ P ≤ 0.049). Disease severity on the outer half leaf portion protected from spray deposition during fungicide application was lower for oxathiapiprolin-based fungicides (1.6 to 6.6%) than observed for fluopicolide + propamocarb (10.9 to 23.7%), mefenoxam + mancozeb (40.3 to 51.4%), and the nontreated controls (83.3 to 84.9%), which indicates significant acropetal movement within the leaf. Postinfection applications of oxathiapiprolin-based formulations had the greatest effect on lesion growth and sporangia production compared with the other fungicides in the experiment. When applied preventively to rapidly growing plants in a greenhouse, oxathiapiprolin-based fungicides consistently protected new growth that was not present at the time of application, with the OD formulation reducing disease severity by >75% relative to nontreated plants. The practical implications of these observations are discussed.

Tortella mediterranea (Pottiaceae), a new species from southern Europe, its molecular affinities, and taxonomic notes on T. nitida

Tortella mediterranea is described as a new species from the Mediterranean Basin of southern Europe. It is mainly characterized by (1) absence of a stem central strand, (2) lanceolate leaf shape, (3) rather gradual limb-sheath transition, (4) partial presence of elongate marginal cells in the upper half of leaf and (5) ventral costal stereid band usually stronger than the dorsal. Chloroplast rps4 and nuclear ITS sequences were invariable within the studied specimens of the species, suggesting a low genetic variability, and the phylogenetic position is rather isolated with only obscure affinities to the group of closely related taxa around T. tortuosa and to T. fasciculata. The new species, seemingly a rather rare plant, was collected from dry and sunny to shaded limestone rocks. In addition, new molecular data for T. nitida s.str. and putative var. irrigata are provided and taxonomic problems within this variable species are discussed.

Learning profitable habitat types by juvenile crayfish

Habitat selection is fundamentally important to animal ecology, and animals that can learn about habitats can increase the probability of avoiding detection by predators or quickly finding food. Here, we tested whether juveniles of the red swamp crayfish, Procambarus clarkii, can learn preference for habitat types based on experience with food availability. Crayfish were housed in arenas with two habitat types, half leaf habitat and half rock habitat. Over several days, crayfish were fed consistently in one of the habitat types. Initial tests revealed that crayfish had an innate preference for the leaf habitat, but conditioning over 2–3 weeks was sufficient to shift this preference to the rock habitat based on habitat cues rather than other spatial cues in their environment. The ability to learn the relevance of habitat features may be an important trait for the colonization success, and subsequent impact, of introduced species.

Effect of Indole-3-butyric Acid and Maturity Level of Single Node Stem Cuttings on Propagation of Exacum ritigalensis

A study was conducted to observe the effect of different concentrations of indole-3-butyric acid (IBA) and maturity levels of single node stem cuttings for vegetative propagation ofE. ritigalensis. Branches of the plant were treated by 20% Clorox in 20 minutes and rinsed it two times using distilled water. Stems cuttings weregrouped into three according to the diameter (20-30 mm, soft wood; 30-40 mm, semi hardwood and 40-50 mm, hardwood).Three differentways of leaves remaining in single node stem cuttings were used; half of single leaf, half double opposite leaves and without leaf. Stem cuttings were treated by IBA (0, 2, 2.5, 5, 10 and 15 mgL-1) for 15 minutes.Plant propagators were prepared by poly bags (150 gauges) and filled by sterilized coir dust. Thereafter, they were kept in two months and observed the survival rates of cuttings (greenish or not),number of roots,length of the lengthiest root, number of buds and number of leaves per bud. Experiments were arranged in three factor factorial completely randomized design (FCRD) with ten replicates. Statistical analysis was performed with Duncan’s multiple range test using SAS software (version 9.1.3). It was observed that rooting was at initial stage of all cuttings after one month. Result were showed that the semi hardwood single node stem with half single leaf or double leavestreated by 10 mgL-1 and 15 mgL-1 IBA were best for rooting compare to other all treatments and control, showed 100% survival rate with three buds per cutting.

云芝多糖对烟草马铃薯Y病毒病的抑制作用及田间防治效果

用1.1%云芝多糖水剂、0.5％香菇多糖水剂、20%病毒A可湿性粉剂采用半叶法在烟苗上进行PVY病斑抑制率测定，结果表明：病斑抑制率分别为83.85%、75.67%、72.2%，以1.1%云芝多糖水剂效果最好。用1.1%云芝多糖水剂、0.5％香菇多糖水剂、20%病毒A可湿性粉剂在大田进行了小区对比试验，结果表明：平均防效分别为83.12%、45.29%、36.29%，以1.1%云芝多糖水剂最好，方差分析表明，差异达极显著水平。 PVY lesion inhibition rate was measured by half leaf method in tobacco seedlings with 1.1% Coriolus Versicolor Polysaccharide agent, 0.5% Letinous edodes agent, 20% Virus A Wettable powder. The results showed that the lesion inhibition rate were 83.85%, 75.67%, 72.2%, 1.1% to the best agent polysaccharide of coriolus versicolor. With 1.1% Coriolus Versicolor Polysaccharide agent, 0.5% Letinous edodes water agent, 20% Virus Agent A in the field of plot comparison experiment results show that the average control effect were 83.12%, 45.29%, 36.29%. The best effect was 1.1% Coriolus Versicolor Polysaccharide agent. In the best agent, the analysis of variance showed that the difference reached a very significant level.