Palisade Parenchyma Research Articles

Solubilization of α-tocopherol and curcumin by polyoxyethylene alkyl ether surfactants: Effect of alkyl chain structure

The effects of the structural characteristics of the alkyl chains of polyoxyethylene alkyl ether-type surfactants (Brij) on the solubilization of α-tocopherol and curcumin by surfactant micelles were investigated: Brij L23 (lauryl; C12:0); S20 (stearyl; C18:0); and Brij O20 (oleyl; C18:1). When α-tocopherol or curcumin were solubilized in Brij micelle solutions below their maximum solubilization concentrations (Cmax), the Brij L23 micelles exhibited the largest increase in dimensions due to the presence of the guest molecules. Above Cmax, excess α-tocopherol existed as microemulsion droplets whereas excess curcumin existed as insoluble crystals. Our results suggest that the guest molecules were preferentially located within the palisade layers of micelles, which can be attributed to the fact that they contained bother polar and non-polar moieties. These results may be important for the formulation of colloidal delivery systems to encapsulate and deliver oil-soluble vitamins and nutraceuticals.

Tissue-specific calcium and magnesium allocation to explain differences in bulk concentration in leaves of one-year-old seedlings of two olive (Olea europaea L.) cultivars

Olive tree (Olea europaea L.) leaves have recently been recognised as a valuable source in cosmetic and pharmaceutical industry as well as in preparation of health-supporting beverages. Little is known about the element composition of olive leaves and almost nothing about tissue-specific allocation of elements. Element composition and tissue-specific distribution were determined in leaves of two olive cultivars, Leccino and Istarska bjelica using micro-particle induced X-ray emission (micro-PIXE). In leaves of the Istarska bjelica cultivar larger bulk concentrations of potassium, sodium, molybdenum and boron, but smaller concentrations of calcium and magnesium were found than in leaves of the Leccino cultivar. Tissue-specific investigation revealed that larger concentration of calcium in epidermis and in leaf blade tissues (secondary veins, palisade and spongy mesophyll) contributed to the larger leaf bulk calcium concentration in the Leccino cultivar. For magnesium, all leaf tissues, except the bundle sheath cells and consequently the main vascular bundle, contributed to the larger bulk concentration in the Leccino cultivar. Potassium was not predominant in any of the leaf tissues examined, while sodium and molybdenum were below the limit of detection, and boron not detectable by micro-PIXE. The results indicate that sinks for calcium and magnesium are stronger in specific leaf tissues of the Leccino than of the Istarska bjelica cultivar. The new understanding of tissue-specific allocation of elements in leaves of olive will serve as a basis for detailed studies into the effects of foliar and/or soil fertilisers in olive.

Mitigation of Powdery Mildew Disease by Integrating Biocontrol Agents and Shikimic Acid with Modulation of Antioxidant Defense System, Anatomical Characterization, and Improvement of Squash Plant Productivity

Squash (Cucurbita pepo L.) is a globally important vegetable, the production of which is severely constrained by powdery mildew caused by Podosphaera xanthii. In this study, we examined the effects of Trichoderma asperellum (MW965676), Streptomyces rochei (MN700192), and a mixture of the two foliar sprays with or without shikimic acid seed priming treatment on powdery mildew severity, plant growth, and total yield during the 2020–2021 and 2021–2022 growing seasons. We also studied their immune eliciting properties by examining their enzymatic, phenolic, and hormonal functions. The combination of Trichoderma asperellum, Streptomyces rochei, and shikimic acid triggered plant defense responses, which elicited enzyme activities such as peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT), phenolic compound accumulation, and increased salicylic acid (SA) and jasmonic acid (JA) content. This approach yielded high-quality results in the control of powdery mildew during the two growing seasons under greenhouse conditions. Additionally, relatively large statistical differences in plant growth, total yield, mineral components, and physiological traits were observed. A GC–MS analysis of Trichoderma asperellum (MW965676) showed hemin cation as a major component, while Streptomyces rochei (MN700192) contained 2,4-di-tert-butyl phenol and the hexadecenoic acid methyl ester. With respect to the morphological changes induced by powdery mildew and the treatments, plants treated with a mixture of Trichoderma asperellum, Streptomyces rochei and shikimic acid showed an improvement in the thickness of the midvein, increased dimensions of the main midvein bundle, a larger number of xylem rows in the main midvein bundle, greater mean diameters of vessels and of parenchyma cells in the ground tissues, as well as increased thickness of the upper and lower epidermis, lamina, palisade tissue and spongy tissue. This extensive, new study is the first step toward a more profound understanding of the use of Trichoderma asperellum and Streptomyces rochei with shikimic acid-primed seeds as a potential alternative technique for attenuating powdery mildew infection in squash.

Micromorphological study of Cordia sinensis Lam. from the Northern Western Ghats, India

The genus Cordia L. is a medicinally important taxon. Cordia sinensis Lam., which is endemic to the Western Ghats of India, is a potential medicinal plant and is presumed to have similar biochemical activities. Since the species is consumed mainly in crude form, it is difficult to establish the identity based on only mature leaf and stem characters. A significant study has been carried out to authenticate the identity of the Cordia genus based on foliar anatomical characters. The anatomical sections of a leaf transverse section and petiole transverse section of the species were observed under the bright-field compound microscope, and observations were documented. Though the diagrammatic outline of the leaf sections is similar, detailed anatomical characters are significantly different. The structure and number of the trichomes are observed abaxial and adaxial sides of the leaves. The trichomes were also found to be valuable characters for identification. In the case of leaf, the number and arrangement of vascular bundles, arrangement of collenchyma at the lower epidermis, palisade cells, and distribution of storage cells are the major characteristics to differentiate other species of Cordia. During the study, we also observed the detailed characters of the cuticular layer, trichomes, and stomatal characters. Rananculious type stomata and the presence of cystoliths in the basal cell of the trichome are the common characteristics observed in the studied species. Based on the preliminary study, the species can be differentiated based only on foliar anatomical characters.

Seasonality of Photosynthetic Physiology and Leaf Anatomy in Three Different Quercus L. Section Cyclobalanopsis Seedlings of Quercus chungii, Quercus gilva, and Quercus glauca in the Subtropical Region of South China

The increasing demand for precious timber resources promotes immediate efforts to develop high-valuable hardwood resources in afforestation. However, the lack of valuable tree species seedlings for afforestation and their ecological adaptability must primarily be addressed. To explore a valuable tree species for precious timber resourcing in afforestation, a comparative analysis of the characteristics of photosynthetic physiology and leaf anatomy in three different Quercus L. Section Cyclobalanopsis seedlings of Quercus chungii, Quercus gilva, and Quercus glauca was performed during three growth stages (July, September, and November) in South China. The results showed that there are significant differences in photosynthetic physiological characteristic parameters, chlorophyll content, and leaf anatomical structure among the three seedlings in each growth stage (p < 0.05). The photosynthetic parameters, i.e., Pn, Gs, Tr, WUE and Ci in each tree species all had the same trend of increase from July to September and decrease from September to November, and with a pick point in September during the three stages. The Pn in Q. chungii was higher than that in the other two species in each stage, and the highest Pn with an average value of 8.26 μmol·m−2·s−1 was obtained in September in Q. chungii, which was 13.77% and 20.06% higher than that of in Q. gilva and Q. glauca at the same time, respectively. Significant differences were also detected in the chlorophyll fluorescence of Fo, Fm, Fv/Fm, Y, ETR, qP, and NPQ among three seedlings within each growth stage from July to November (p < 0.05). The thickness of the mature leaf was decreased in order as Q. chungii, Q. glauca, and Q. gilva. From July to September, more notable changes were observed in Q. chungii in September, with a drop of 3.49% in leaf thickness, and a drop of 3.34% and 10.06% in the volume of palisade tissue and sponge tissue, respectively. Consequently, increasing tightness and deducing looseness were observed in Q. chungii. The principal component analysis (PCA) on photosynthesis and leaf anatomy showed that Q. chungii displayed a stronger photosynthetic physiology with a positive coordination on water, air, light, and heat. These findings facilitate the evaluation of ecological adaptability among the three Quercus seedlings and provide compelling evidence for the application of Q. chungii for precious timber resources in afforestation.

Molecular mechanism of leaf adaxial upward curling caused by BpPIN3 suppression in Betula pendula.

Leaves are one of the vegetative organs of plants that are essential for plant growth and development. PIN-FORMED (PINs) gene is an indoleacetic acid (IAA) transporter that plays a critical role in leaf development. To determine the function of BpPIN3 in leaf polarity formation in Betula pendula, the transgenic lines with BpPIN3 overexpression (OE) and BpPIN3-reduced expression (RE) were analyzed using the Agrobacterium-mediated method. The RE lines displayed the characteristics of leaf margin adaxial upward curling, with lower expression of BpPIN3 resulting in greater rolling. Tissue localization of IAA in the auxin GUS reporter system proved that auxin in the RE was mainly distributed in the secondary veins, palisade tissues, and epidermal cells in the leaf margin area. The auxin content in the leaf margin area was significantly greater than that in the main vein tissue. The cell density of the palisade tissue and the ratio of palisade tissue to spongy tissue in the curled leaf margin of the RE lines were found to be significantly decreased. RNA-seq analysis revealed that the RE hormone-signaling pathway genes were significantly enriched compared with those of the OE and WT lines; in particular, the auxin response-related genes SAURs (i.e., SAUR23, SAUR24, SAUR28, and SAUR50) and GH3.10 were found to be significantly upregulated. qRT-PCR analysis indicated that BpPIN3 expression at the leaf margin was significantly lower than that near the main vein in the RE lines. In contrast, the expression levels of SAURs and GH3.10 were significantly higher than those near the midrib. In conclusion, BpPIN3 regulates the expression of auxin response-related genes and the polar transport of auxin to change the polar form of the proximal and distal axes of birch leaves.

Change in leaf anatomy, physiology, and essential oil of Varronia curassavica Jacq. accessions under two light conditions

The aim of this study was to evaluate the effect of light on anatomy, physiology and essential oil content and composition of Varronia curassavica. They were analysed two light conditions (full sunlight and protected environment with 50% shade screen) and five accessions (VCUR-101, VCUR-102, VCUR-201, VCUR-302, VCUR-802). V. curassavicacultivated in full sun presented a greater development of the leaf blade and palisade parenchyma thickness for all accessions. Chlorophyll levels did not differ according to the two light environments. The leaf area was larger in the protected environment. The essential oil yield of the accessions ranged from 0.26 to 0.87 mL/plant in full sun and from 0.34 to 0.53 mL/plant in the protected environment. The composition of the essential oil was influenced by the light and the accession. All accessions presented (E)-caryophyllene and α-humulene. The influence of light on the evaluated variables is genotype dependent.

Sunflower Leaf Structure Affects Chlorophyll a Fluorescence Induction Kinetics In Vivo

Chlorophyll a fluorescence induction kinetics (CFI) is an important tool that reflects the photosynthetic function of leaves, but it remains unclear whether it is affected by leaf structure. Therefore, in this study, the leaf structure and CFI curves of sunflower and sorghum seedlings were analyzed. Results revealed that there was a significant difference between the structures of palisade and spongy tissues in sunflower leaves. Their CFI curves, measured on both the adaxial and abaxial sides, also differed significantly. However, the differences in the leaf structures and CFI curves between both sides of sorghum leaves were not significant. Further analysis revealed that the differences in the CFI curves between the adaxial and abaxial sides of sunflower leaves almost disappeared due to reduced incident light scattering and refraction in the leaf tissues; more importantly, changes in the CFI curves of the abaxial side were greater than the adaxial side. Compared to leaves grown under full sunlight, weak light led to decreased differences in the CFI curves between the adaxial and abaxial sides of sunflower leaves; of these, changes in the CFI curves and palisade tissue structure on the adaxial side were more obvious than on the abaxial side. Therefore, it appears that large differences in sunflower leaf structures may affect the shape of CFI curves. These findings lay a foundation for enhancing our understanding of CFI from a new perspective.

Heat and Cold-Stressed Individuals of Pistacia lentiscus (Mastic Tree) Do Modify Their Secreting Profile.

Seedlings from the germinated seeds of Pistacia lentiscus were cultured in plant growth chambers for three months. Then, the plants were separated into three groups. Each group was cultured under different conditions. The first group was left to grow under normal Mediterranean conditions, as those recorded in spring. The other group was subjected to a ten-day heat stress while the last one also suffered a cold stress for ten days. The anatomical features of the leaves (leaf thickness, epidermal cell thickness, number of palisade layers, and development) between these three groups differed. The stressed plants accumulated large amounts of phenolics within their mesophyll cells. The biomass of the cold-stressed plants was minor, while it was high for the control plants. The oxidative stress was hardly detectable in the leaves of the control plants, while their heat-stressed counterparts suffered the highest concentration of reactive oxygen species. Differences concerning the absorption spectra of the three groups of leaves were not significant. An interesting incompatibility between the three groups concerned the expression of L-Dopa Decarboxylase, which climbed significantly in the heat-stressed plants. Finally, an interesting variation was observed concerning the concentrations of some biogenic amines/amino acids. This variation can be correlated to the other stress-induced reactions of the plants and, in some cases, was impressive. In conclusion, environmental stress can shift Pistacia lentiscus' metabolism to synthesize different biogenic products, which can be considered as exploitable for the pharmaceutical or food industry.

Translocation and Utilization Mechanisms of Leaf Intracellular Water in Karst Plants Orychophragmus violaceus (L.) O. E. Schulz and Brassica napus L.

Orychophragmus violaceus (L.) O. E. Schulz adapts to karst environments through a variety of adaptability mechanisms. However, the leaf intracellular water translocation and utilization mechanism is still unknown. This study hypothesizes that plants adapt to dehydration by synergistically adjusting the leaf anatomy, cell elasticity and intracellular water translocation. Leaf structure, elastic modulus (Em), physiological capacitance (CP), impedance (Z), water potential (ΨL), leaf tensity (LT) and chlorophyll fluorescence parameters of the detached leaves in plants of O. violaceus and Brassica napus L. were measured at each water loss time (0, 1, 2, 3, 4 and 5 h). The uniform leaves were randomly selected from five different plants for each species. The cell vacuole volume and translocation resistance of intracellular water could be represented by the electrophysiological parameters, such as CP and Z. The results indicated that timely shrinkage of O. violaceus leaves and mesophyll cells together with the increased water translocation resistance retained the intracellular water and maintained the turgor pressure. Water within sponge parenchyma could also be translocated into palisade parenchyma. The PSII reaction center was kept stable, and the photosynthetic activity of O. violaceus was clearly inhibited at 3 h. Palisade parenchyma of B. napus leaves increased quickly to improve the intercellular water translocation due to the strong cell stiffness. Gradually increasing intracellular water translocation resistance and recovery of the cell elasticity slowed down the leaf water loss, which, however, could not timely stop the damage on the PSII reaction center and the photochemical efficiency. The photochemical efficiency was seriously inhibited at 4 h and 5 h. The response mechanism of intracellular water to dehydration can be investigated with the help of leaf electrophysiological traits. However, the direct determination of plant drought resistance using electrophysiological information can still not be realized at present and needs further research.

On-field optical imaging data for the pre-identification and estimation of leaf deformities

Visually nonidentifiable pathological symptoms at an early stage are a major limitation in agricultural plantations. Thickness reduction in palisade parenchyma (PP) and spongy parenchyma (SP) layers is one of the most common symptoms that occur at the early stage of leaf diseases, particularly in apple and persimmon. To visualize variations in PP and SP thickness, we used optical coherence tomography (OCT)-based imaging and analyzed the acquired datasets to determine the threshold parameters for pre-identifying and estimating persimmon and apple leaf abnormalities using an intensity-based depth profiling algorithm. The algorithm identified morphological differences between healthy, apparently-healthy, and infected leaves by applying a threshold in depth profiling to classify them. The qualitative and quantitative results revealed changes and abnormalities in leaf morphology in addition to disease incubation in both apple and persimmon leaves. These can be used to examine how initial symptoms are influenced by disease growth. Thus, these datasets confirm the significance of OCT in identifying disease symptoms nondestructively and providing a benchmark dataset to the agriculture community for future reference.

Effects of NaCl Stress on the Growth, Physiological Characteristics and Anatomical Structures of Populus talassica × Populus euphratica Seedlings.

In order to elucidate the salt tolerance mechanism of Populus talassica × Populus euphratica, the growth, physiology and anatomical characteristics of P. talassica × P. euphratica were studied under different concentrations of NaCl-stress treatments. In this study, the annual seedlings of Populus talassica × Populus euphratica were used as the test material in a field potted control experiment. The basic salt content of the culture soil was the control (CK), and two NaCl treatments of 200 mmol/L and 400 mmol/L were established. The pot experiment showed that: (1) Compared with CK, the 200 mmol/L NaCl-stress treatment significantly increased the growth parameters of P. talassica × P. euphratica, such as leaf area, plant height, ground diameter, biomass, root length, root surface area, root fork number and root-shoot ratio. However, compared with CK, the 400 mmol/L NaCl-stress treatment significantly reduced most growth parameters. (2) The 200 and 400 mmol/L NaCl-stress treatments significantly decreased various physiological parameters such as relative water content (RWC), chlorophyll content, water potential, stomatal opening and photosynthetic parameters and increased the accumulation of MDA and Pro compared with CK. The 200 mmol/L NaCl-stress treatment significantly increased the activity of antioxidant enzymes, and the 400 mmol/L NaCl-stress treatment significantly decreased the activity of antioxidant enzymes. (3) Compared with CK, 200 and 400 mmol/L NaCl-stress treatments significantly improved the leaf palisade tissue thickness and palisade-to-sea ratio, as well as the stem xylem and stem phloem thickness and pith diameter, and significantly increased the root xylem thickness, root phloem thickness, and root cross-cutting diameter of P. talassica × P. euphratica. The growth, physiological characteristics and anatomical characteristics of P. talassica × P. euphratica under NaCl-stress treatments showed that it had good salt tolerance and adaptability, and the 200 mmol/L NaCl-stress treatment promoted the growth of P. talassica × P. euphratica to a certain extent. This study provided a theoretical basis for the study of the salt-tolerant mechanism of P. talassica × P. euphratica.

Early leaf development of Typha domingensis Pers. (Typhaceae)

ABSTRACT Typha domingensis Pers. (cattail) is a globally widespread aquatic plant that causes significant impacts as an invasive species; this ability is dependent on its photosynthetic capacity that is related to leaves. Thus, understanding leaf development is essential for interpreting shoot growth and the formation of its photosynthetic area. This study investigates leaf ontogeny in T. domingensis from early stages until complete development of primary tissues. Plants were collected from natural wetlands and cultivated in a greenhouse. Rhizomes were then selected, and leaves were removed to enable the emergence of new shoots. Rhizome fragments containing leaves were collected at 1-day intervals until day 7 and were subjected to routine procedures in plant microtechnique. New leaves emerged from lateral buds located along the rhizome. The anatomy of scale leaves differs from that of photosynthetic leaves since they contain solid inclusions without palisade parenchyma. Leaf primordia arose laterally from the shoot apical meristem, which was organized as a tunica-corpus. Final leaf shape was influenced by different meristematic zones: the leaf apical meristem, the marginal meristem, the rib meristem, and intercalary meristems. Most leaf tissues developed basipetally, except for xylem and phloem. Within seven days following leaf initiation, all primary tissues were developed and morphologically functional. Leaf formation of Typha domingensis is similar to that of other monocot species. Leaves of T. domingensis develop very early, providing fully functional photosynthetic tissues, which may have implications for its invasive capacity.

Foliar nutrition alleviate citrus plants from Asian citrus psyllid feeding by affecting leaf structure and secondary metabolism

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae) is the primary vector of pathogenic bacteria disseminating Huanglongbing. Nutrients enhancement have been reported to be few optional methods to relieve Huanglongbing. However, limited studies have focused on the interactions between citrus plants and psyllid under nutritional enhancement. The present work was conducted to study psyllid feeding and psyllid feeding with nutrients enhancement. Our results suggested that psyllid feeding up-regulated the amino acid metabolism especial phenylalanine of leaf, which hence attracted more insect adults. Psyllid feeding significantly decreased palisade tissue pectin methylation but increased fibrous ring tissue, with increasing the concentration of different nutrients of leaves, resulted in an increased leaf thickness, leaf weight, and leaf dry mass per unit area. These changes facilitated psyllid feeding process, embodied in increased phloem ingestion and decrease in piercing process. While, foliar supply of nutrients affected the leaf nutrient composition, having cascading effect on down-regulation of amino acids mediated metabolism coupled with poor growth of palisade tissues, but accelerated the growth of fibrous ring tissues inhibited the ability of psyllid to recognize host, thereby, reduced the feeding efficiency of psyllid. Compared with the pesticide treatment, pesticide+nutrients treatment showed a higher reduction rate of psyllid population. Our study, hence, provided some evidences about behavior of psyllid under three distinct feeding environments, for insightful analysis of behavioral dynamics of psyllid feeding, an issue considered important for uncontrolled spread of Huanglongbing.

Congolese edible caterpillars, valuable sources of bioactive compounds with human health benefits

Insects are part of the regular diet of more than two billion people around the world and are not only delicacies. Insects provide great opportunities to replace meals but can have important additional benefits as well. In the Democratic Republic of the Congo (DRC), caterpillars are the most consumed insects, and they are consumed by more than 70% of the population throughout the year. The aim of this research was to report the microscopic features, mineral micronutrients, chromatographic fingerprints, antioxidant activities and peroxidase inhibition of edible Congolese caterpillars of the genusCinabra, Imbrasia andGonimbrasia from DRC. Microscopic analysis showed the presence of characteristic features, specific to each host plant of caterpillars, such as palisade cells, stomata, trichomes, sclereids, fibres, vessels, pollen and starch grains. Phytochemical screening by chromatographic techniques revealed the presence of phenolic acids, flavonoids and terpenes as major secondary metabolites. Elemental analysis on dry matter showed that studied caterpillars are insects containing significant amounts of micronutrients such as copper, magnesium, manganese, selenium and zinc.Gonimbrasia belina had the highest selenium, magnesium and zinc content (0.12 g/100 g, 0.17 g/100 g and 0.011 g/100 g, respectively) thanCirina forda, Cinabra hyperbius, Imbrasia truncata andImbrasia sp., C. forda andImbrasia sp. had the highest copper content (0.003 g/100 g).C. forda had the highest manganese content (0.006 g/100 g). All aqueous extracts displayed high radical-scavenging activities with IC50 values ranging from 10 to 80 μg/ml. Extracts showed the best cellular antioxidant activities on reactive oxygen species-induced chemiluminescence using L012 on human leucocytes 60 monocytes related to their IC50 values less than 0.5 μg/ml. In specific immuno-extraction followed by enzymatic detection of myeloperoxidase assay, all extracts of caterpillars exhibited a dose-dependent inhibitory effect on myeloperoxidase activity in the range concentrations of 1 to 20 μg/ml excepted extracts ofImbrasia epimethea,Imbrasia sp. andI. truncata. Our results showed that insects are not only valuable source of lipids, proteins and micronutrients such as selenium but also are sources of phytochemicals with therapeutic benefits.

Transcriptional analysis of grape in response to weak light stress

Grape (Vitis vinifera L.) in production is frequently exposed to inadequate light, which significantly affects its agronomic traits via inhibiting their physiological, metabolic and developmental processes. To explore the mechanism how the grape plants respond to the weak light stress, we used 'Yinhong' grape and examined their physiology-biochemistry characteristics and transcriptional profile under different levels of weak light stress. The results showed that grape seedlings upon low intensity shading treatments were not significantly affected. As the shading stress intensity was strengthened, the epidermis cells, palisade tissue, and spongy tissue in the leaves were thinner, the intercellular space between the palisade tissue and spongy tissue was larger compared with that of the control, and the activities of superoxide dismutase, catalase and peroxidase were decreased gradually. Additionally, the soluble protein content increased and the free proline content decreased gradually. Compared with the control, significant changes in plant photosynthetic characteristics and physiology-biochemistry characteristics were observed under high intensity of shading (80%). RNA-seq data showed that the differentially expressed genes between CK and T2, CK and T4, T2 and T4 were 13 913, 13 293 and 14 943, respectively. Most of the enrichment pathways were closely related with the plant's response to stress. Several signaling pathways in response to stress-resistance, e.g. JA/MYC2 pathway and MAPK signal pathway, were activated under weak light stress. The expression level of a variety of genes related to antioxidation (such as polyphenol oxidase and thioredoxin), photosynthesis (such as phytochrome) was altered under weak light stress, indicating that 'Yinhong' grape may activate the antioxidation related pathways to cope with reactive oxygen species (ROS). In addition, it may activate the expression of photosynthetic pigment and light reaction structural protein to maintain the photosynthesis activity. This research may help better understand the relevant physiological response mechanism and facilitate cultivation of grape seedlings under weak light.

Depolymerization of polyaromatic hydrocarbons by Penicillium spp. inhabit the phyllosphere of urban ornamental plants

AbstractA variety of anthropogenic sources release hazardous polyaromatic hydrocarbons (PAHs) into the phyllosphere which is an excellent niche for diverse fungi, and some of them have PAHs degradation capabilities. Therefore, this research attempted to determine the PAHs (phenanthrene, anthracene, naphthalene, and pyrene) degradation capability of phyllosphere inhabited Penicillium species. The leaf samples were collected from highly polluted urban areas (Panchikawatta, Pettah, Orugodawatta, Maradana, Sapugaskanda, and Colombo Fort) in Sri Lanka to isolate fungal species inhabiting the phyllosphere. Furthermore, their distribution patterns among the leaf tissue layers were studied using bright‐field microscopic observations. Moreover, the best PAH degraders were screened out using plate assays and confirmed through High Performance Liquid Chromatography (HPLC) analysis. Further, their enzymatic activities during the PAHs degradation were analyzed. As per the microscopic observations, the highest fungal distribution was in the upper epidermis of the leaves followed by the fungal distribution in the interspaces of palisade mesophyll layers. Out of isolated fungal species, two Penicillium spp. (Penicillium citrinum P23B‐91 and Penicillium griseofulvum P9B ‐ 30) showed the highest PAHs (phenanthrene, anthracene, naphthalene, and pyrene) degradation capabilities. Manganese peroxidase (MnP) enzyme dominated phenanthrene degradation in P. griseofulvum P9B ‐ 30, which showed the highest phenanthrene degradation ability (61%). In addition, P. citrinum P23B‐91 was good at degrading anthracene (88%) and also displayed a higher MnP activity during the anthracene degradation than laccase and lignin peroxidase activities. The discoveries from the toxicity assay during the PAHs degradation processes revealed that the produced byproducts had no toxic effects on the fungal growth cycle and the phyllosphere. Therefore this phyllosphere Penicillium spp. are ideal for the bioremediation of polluted air in urbanized areas.

A Comparison between Vitamin D3 and 25-Hydroxyvitamin D3 on Laying Performance, Eggshell Quality and Ultrastructure, and Plasma Calcium Levels in Late Period Laying Hens.

Simple SummaryThe sharp decline of laying performance and eggshell quality is a common problem in late period laying hens. Vitamin D3 (VD3) is a necessary micronutrient which plays an important role in mineral and skeletal homeostasis. With the rapid development of genetic selection, commercial laying hens have increased requirements for performance and nutrients. The commercial supplementary dose of VD3 (62.5 µg/kg) for late period laying hens may be not enough to satisfy the production. In addition, 25-hydroxyvitamin D3 (25-OHD3) as an active metabolite of VD3, is a viable alternative to replace VD3. Therefore, the objective of this study was to compare the effects of different supplementary doses and sources between VD3 and 25-OHD3 on the laying performance and eggshell quality in late period laying hens. The results showed that supplementary 125 µg/kg doses of VD3 or 25-OHD3 had better effects in late period laying hens compared with 62.5 µg/kg doses of VD3. Additionally, there were no different effects on laying performance or eggshell quality in the hens fed dietary 125 µg/kg doses of VD3 or 25-OHD3.The objective of this study was to compare high supplementary doses (125 µg/kg) of vitamin D3 (VD3) or 25-hydroxyvitamin D3 (25-OHD3) with commercial supplementary doses (62.5 µg/kg) of VD3 on laying performance, eggshell quality and ultrastructure, and plasma calcium levels in late period laying hens. A total of 1512 Roman Gray (60-week-old) laying hens were allotted into three treatments with 12 replicates and 42 birds in each replicate. During the 12-week trial period, the layers were fed a basal diet supplemented with different doses of VD3 or 25-OHD3 (62.5 µg/kg VD3 in control group, CON; 125 µg/kg VD3 in high level VD3 group, VD3; 125 µg/kg 25-OHD3 in high level 25-OHD3 group, 25-OHD3). The results showed that high supplementary doses of VD3 or 25-OHD3 increased laying rate (p < 0.05). Moreover, the layers fed high doses of VD3 or 25-OHD3 diets had decreased unqualified egg rate and mortality (p < 0.05). High supplementary doses of VD3 or 25-OHD3 increased eggshell strength and eggshell thickness (p < 0.05). From observation in eggshell ultrastructure, high doses of VD3 or 25-OHD3 diets increased the palisade layer thickness and mammillary knob density (p < 0.05). Furthermore, high doses of VD3 or 25-OHD3 diets increased the calcium levels in plasma (p < 0.05). In summary, compared with 62.5 µg/kg doses of VD3, supplementary 125 µg/kg doses of VD3 or 25-OHD3 improved the laying performance, eggshell quality, and plasma calcium levels in late period laying hens. Additionally, there was an equal effect on laying performance and eggshell quality in the hens fed dietary 125 µg/kg doses of VD3 or 25-OHD3.

Effects of Plant-Growth-Promoting Rhizobacteria (PGPR) and Cyanobacteria on Botanical Characteristics of Tomato (Solanum lycopersicon L.) Plants.

Tomatoes are an important agricultural product because they contain high concentrations of bioactive substances, such as folate, ascorbate, polyphenols, and carotenoids, as well as many other essential elements. As a result, tomatoes are thought to be extremely beneficial to human health. Chemical fertilizers and insecticides are routinely utilized to maximize tomato production. In this context, microbial inoculations, particularly those containing PGPR, may be utilized in place of chemical fertilizers and pesticides. In this study, we investigated the effects of PGPR (Bacillus subtilis, and Bacillus amyloliquefaciens) and cyanobacteria when utilized alone, and in conjunction with each other, on the growth, quality, and yield of fresh fruits of tomato plants. The results showed that the inoculation significantly increased all measured parameters of tomato plants compared with the control. Combined use of B. subtilis and B. amyloliquefaciens had a positive impact on tomato yield, increasing fruit yield. Moreover, leaflet anatomical characteristics were altered, with increased thickness of the upper epidermis, lower epidermis, palisade tissue, spongy tissue, and vascular bundles. Tomato fruit quality was improved, as measured by an increased number of fruit per plant (76% increase), fruit weight (g; 33% increase), fruit height (cm; 50% increase), fruit diameter (cm; 50%), total soluble solids (TSS; 26% increase), and ascorbic acid (mg/100 g F.W.; 75% increase), relative to the control, in the first season. In addition, fruit chemical contents (N, P, and K) were increased with inoculation. The results suggest that inoculation with B. subtilis and B. amyloliquefaciens could be successfully used to enhance tomato plant growth and yield.

Genome-wide identification and characterization of OVATE family proteins in Betula luminifera reveals involvement of BlOFP3 and BlOFP5 genes in leaf development.

Ovate family proteins (OFP) are plant-specific transcription factors involved in regulating morphologies of the lateral organs, plant growth and development. However, the functional roles of OFP genes in Betula luminifera, an important timber tree species, are not well studied. In this study, we identified 20 BlOFP genes and analyzed their phylogenetic relationship, gene structure, conserved motifs, and cis-elements. Further, expression analysis indicates that BlOFP genes were up-regulated in leaves on the one-year-old branch compared to leaves on the current-year branch and bract, except BlOFP7, BlOFP11, BlOFP14 and BlOFP12. The overexpression of BlOFP3 and BlOFP5 in Arabidopsis thaliana not only resulted in a slower growth rate but also produced sawtooth shape, flatter and darker green rosette leaves. Further investigation showed that the leaf thickness of the transgenic plants was more than double that of the wild type, which was caused by the increasement in the number and size of palisade tissue cells. Furthermore, the expression analysis also indicated that the expressions of several genes related to leaf development were significantly changed in the transgene plants. These results suggested the significant roles of BlOFP3 and BlOFP5 in leaf development. Moreover, protein-protein interaction studies showed that BlOFP3 interacts with BlKNAT5, and BlOFP5 interacts with BlKNAT5, BlBLH6 and BlBLH7. In conclusion, our study demonstrates that BlOFP3 and BlOFP5 were involved in leaf shape and thickness regulation by forming a complex with BlKNAT5, BlBLH6 and BlBLH7. In addition, our study serves as a guide for future functional genomic studies of OFP genes of the B. luminifera.