Aerial Parts Of Plant Research Articles

Lipopeptide-enriched extracts of Bacillus velezensis B157 for controlling tomato early blight

Bacillus strains used in plant disease control produce cyclic lipopeptides (LPs) with antifungal activities. The LP concentration in Bacillus-cell suspensions may be insufficient to protect aerial plant parts against phytopathogens and the de novo metabolite production by bacteria on leaf surfaces is limited, leading to inconsistent control results in the field. We investigated the use of LP-enriched crude organic extracts of Bacillus velezensis strain B157 for controlling early blight, a destructive tomato disease caused by Alternaria linariae. Liquid chromatography–tandem mass spectrometry-based LP dereplication and molecular networking analysis revealed a complex mixture of iturins, fengycins, and surfactins in the organic extract of B157. Fengycins and iturins showed a marked in vitro antifungal activity. Treating tomato plants with the organic extract significantly reduced the severity of early blight, attaining more than 90% of disease control efficacy in two independent greenhouse experiments. These results show the potential of using LP-enriched biochemical fungicides for plant disease control.

Chemical components of essential oils from aerial parts of Pycnanthemum virginianum and P. californicum (Lamiaceae) plants

Aim. The research is aimed at determining the qualitative and quantitative content of essential oils in the aerial part of two species of the genus Pycnanthemum Michx. (Lamiaceae) – P. virginianum (L.) T. Durand & B.D. Jacks. ex B.L. Rob & Fernald and P. californicum Norr. exDurand. The plants were introduced in the M. M. Gryshko National Botanical Garden of National Academy of Sciences of Ukraine (Forest-Steppe zone). These are representatives of the flora of North America, and they are little known in Ukraine. Plants have useful medicinal and nutritional properties, but the biochemical composition of their essential oils has not been sufficiently studied in the world.Materials and methods. In the experiment, the aerial herbal part of plants collected during the flowering phase was used. The quantitative content of the essential oil was determined by the hydrodistillation method, and its qualitative characteristics were found by the GC-MS analysis. The chromatographic profile was obtained on an Agilent Technologies 7890. The component composition of the essential oil was determined on a gas chromatograph with a HP 6890 mass spectrometric detector with a mass spectrometric detector 5973. We used a mass spectrometric detector 1.6 – 800 a.o.m., EI ionization, SIM & Scan mode, “Hewlett Packard”, USA. Identification of essential oil components was performed using the NIST mass spectrum library in combination with AMDIS content-time identification programs.Results and discussion. P. virginianum was found to produce 1.96 ± 0.17 % of essential oil, in which 12 compounds out of 13 were identified; P. californicum had 2.66 ± 0.13 % of essential oil, 13 compounds out of 15 were identified. The essential oil samples obtained have pulegone as the dominant component: P. virginianum – 44.65 %, P. californicum – 86.07 %. In addition to it, they also contain thymol, myrcene, 1.8-cineole, menthone, limonene and other compounds.Conclusions. For the first time, the qualitative and quantitative composition of the essential oils of plants of P. virginianum and P. californicum species introduced in Ukraine has been determined. The results obtained indicate that when introduced plants have a high biosynthesizing ability to produce essential oil. Pulegone has been found to be the dominant component; therefore, the essential oil can be classified as a pulegone-type essential oil. We believe that the raw material of P. virginianum and P. californicum are potentially suitable for use in perfumery, cosmetics, aromatherapy, personal care products, dentistry, and in the pharmaceutical and food industries.

Chitosan and salty irrigation water affect morphological and physiological characteristics of rosemary herb

There are numerous uses for rosemary essential oil (Rosmarinus officinalis), including aromatherapy, antioxidant activity, antimicrobial and antitumour properties. High salinity of irrigation water is one of the main barriers inhibiting the growth of rosemary cultivation in Egypt's new reclamation zones. Chitosan is a natural biopolymer which is obtained from the deacetylation of chitin and has a high potential to improve plant productivity under stressful conditions. So, this study aimed to minimize the negative effects of salty irrigation water on rosemary plants by assisting them in adjusting to salt stress through foliar application of chitosan to determine the potential for increasing their cultivation in the new reclamation zones as a natural supply of essential oil. Rosemary plants were subjected to different doses of salty irrigation water (0, 25.7, 51.3, 77.0, 102.6 mM) without or with chitosan (6 mg L-1). Plants irrigated by salty water with spraying chitosan resulted in higher values of plant aerial parts, photosynthetic pigments, carbohydrates, protein, phenols, flavonoids, antioxidant enzymes (peroxidase and superoxide dismutase), essential oil, nitrogen, phosphorous and potassium than those irrigated by salty water without chitosan. In contrast, lower amounts were found in free radical scavenging, sodium and chloride of plant treated with salty water x chitosan than those treated with saline water only. Saline water, chitosan, and their interactions caused a number of changes in detected amino acids and essential oil components. It may be summarized that productivity of rosemary plants can be improved with adapting them under saline irrigation conditions by adding chitosan. This trial benefits the producers of rosemary to alleviate the hurtful effects of saline water in reclaimed regions with adding chitosan.

Phytochemical profile and biological activities of the essential oils in the aerial part and root of Saposhnikovia divaricata

The dried root of Saposhnikovia divaricata (Turcz.) Schischk. is popular as a good medicinal material, however the abundant aerial part is often discarded, which caused the waste of resources. In order to exploit resources, the essential oils of the plant aerial part and root were extracted, separately called as VOA and VOR, their chemicals were identified. The tumor necrosis factor-α, interleukin-6, nitric oxide and interleukin-1β were detected to evaluate the oils anti-inflammatory activities. Then, the oils free radical scavenging rates were measured with DPPH, ABTS and hydroxyl free radical. The oils antitumor activities were evaluated with HeLa and HCT-8 cancer cell lines. The results showed the concentrations of VOA and VOR were separately 0.261% and 0.475%. Seventeen components of VOA were identified, accounting for 80.48% of VOA, including phytol, spathulenol, phytone, 4(15),5,10(14)-Germacratrien-1-ol, neophytadiene, etc. Seven components of VOR were determined, representing 90.73% of VOR, consisted of panaxynol, β-bisabolene, etc. VOA and VOR significantly inhibited the secretion of nitric oxide, interleukin-1β, interleukin‐6 and tumor necrosis factor-α, effectively scavenged the DPPH, ABTS and hydroxyl free radicals, and showed significant antiproliferative activity against HeLa and HCT-8. The two oils presented important biological activity, which provided a hopeful utilized basis, and helped to reduce the waste of the aerial non-medicinal resources of S. divaricata.

Localization of Sesquiterpene Lactones Biosynthesis in Flowers of Arnica Taxa.

Arnica montana is a valuable plant with high demand on the pharmaceutical and cosmetic market due to the presence of helenalin (H) and 11α, 13-dihydrohelenalin (DH) sesquiterpene lactones (SLs), with many applications and anti-inflammatory, anti-tumor, analgesic and other properties. Despite the great importance of these compounds for the protection of the plant and their medicinal value, the content of these lactones and the profile of the compounds present within individual elements of florets and flower heads have not been studied so far, and attempts to localize these compounds in flower tissues have also not been conducted. The three studied Arnica taxa synthesize SLs only in the aerial parts of plants, and the highest content of these substances was found in A. montana cv. Arbo; it was lower in wild species, and a very small amount of H was produced by A. chamissonis. Analysis of dissected fragments of whole inflorescences revealed a specific distribution pattern of these compounds. The lactones content in single florets increased from the top of the corolla to the ovary, with the pappus calyx being a significant source of their production. Histochemical tests for terpenes and methylene ketones indicated the colocalization of lactones with inulin vacuoles.

Exogenous hydrogen sulfide alleviates chromium toxicity by modulating chromium, nutrients and reactive oxygen species accumulation, and antioxidant defence system in mungbean (Vigna radiata L.) seedlings

Chromium (Cr), a highly toxic redox-active metal cation in soil, seriously threatens global agriculture by affecting nutrient uptake and disturbing various physio-biochemical processes in plants, thereby reducing yields. Here, we examined the effects of different concentrations of Cr alone and in combination with hydrogen sulfide (H2S) application on the growth and physio-biochemical performance of two mungbeans (Vigna radiata L.) varieties, viz. Pusa Vishal (PV; Cr tolerant) and Pusa Ratna (PR; Cr sensitive), growing in a pot in hydroponics. Plants were grown in the pot experiment to examine their growth, enzymatic and non-enzymatic antioxidant levels, electrolyte balance, and plasma membrane (PM) H+-ATPase activity. Furthermore, root anatomy and cell death were analysed 15 days after sowing both varieties in hydroponic systems. The Cr-induced accumulation of reactive oxygen species caused cell death and affected the root anatomy and growth of both varieties. However, the extent of alteration in anatomical features was less in PV than in PR. Exogenous application of H2S promoted plant growth, thereby improving plant antioxidant activities and reducing cell death by suppressing Cr accumulation and translocation. Seedlings of both cultivars treated with H2S exhibited enhanced photosynthesis, ion uptake, glutathione, and proline levels and reduced oxidative stress. Interestingly, H2S restricted the translocation of Cr to aerial parts of plants by improving the nutrient profile and viability of root cells, thereby relieving plants from oxidative bursts by activating the antioxidant machinery through triggering the ascorbate-glutathione cycle. Overall, H2S application improved the nutrient profile and ionic homeostasis of Cr-stressed mungbean plants. These results highlight the importance of H2S application in protecting crops against Cr toxicity. Our findings can be utilised to develop management strategies to improve heavy metal tolerance among crops.

Trifolium pratense and the Heavy Metal Content in Various Urban Areas

Effective biomonitoring strategies are essential for identifying and assessing the sources and levels of contamination of heavy metal pollutants in urban areas, given their negative impacts on human health and the environment. This study aimed to assess the potential of common weed, Trifolium pratense as a bioindicator of heavy metal contamination in various land uses in urban areas, with a focus on Cd, Cu, Cr, Ni, and Pb. The results have shown that Cr and Ni had high bioconcentration factor (BCF) values in most sites, in comparison with Cu, Cd and Pb. Contamination factor (CF) values varied across all sites. The industrial area and old town sites had the highest translocation factor (TF) values for Cr and Ni, indicating greater transport of these metals from roots to aerial parts of plants. Differences between heavy metals (HMs) according to land use were observed; especially, Pb and Cu were more concentrated in soils than other heavy metals in industrial areas. Overall, these findings suggest that Trifolium pratense is a promising bioindicator for heavy metal contamination in various land uses in urban areas, making it a potentially valuable tool for monitoring heavy metal pollution in cities of the northern hemisphere.

Mechanisms of As, Cd, Pb, and Zn hyperaccumulation by plants and their effects on soil microbiome in the rhizosphere

Excess potentially toxic elements (PTEs), including arsenic (As), cadmium (Cd), lead (Pb), and zinc (Zn), above permissible limits in the environment, have detrimental effects on trophic levels. Hence, imperative to devise advertent measures to address this situation, especially in the soil ecosystem: the major reservoir of many PTEs. Using aerial plant parts (shoot) to accumulate As, Cd, Pb, and Zn - hyperaccumulators are considered a permanent approach to PTE removal from soils. This communication expatiated the principles that govern the hyperaccumulation of plants growing on As, Cd, Pb, and Zn-contaminated soils. The contribution of soil microbial communities during hyperaccumulation is well-elaborated to support the preference for this remediation approach. The study confirms a flow direction involving PTE uptake–translocation–tolerance–detoxification by hyperaccumulators. Rhizosphere microbes exhibit a direct preference for specific hyperaccumulators, which is associated with root exudations, while the resultant formation of chelates and solubility of PTEs, with soil physicochemical properties, including pH and redox potential, promote uptake. Different compartments of plants possess specialized transporter proteins and gene expressions capable of influx and efflux of PTEs by hyperaccumulators. After PTE uptake, many hyperaccumulators undergo cellular secretion of chelates supported by enzymatic catalysis and high transport systems with the ability to form complexes as tolerance and detoxification mechanisms. The benefits of combining hyperaccumulators with beneficial microbes such as endophytes and other rhizosphere microbes for PTE removal from soils are vital in enhancing plant survival and growth, minimizing metal toxicity, and supplying nutrients. Inoculation of suitable rhizosphere microbes can promote efficient cleaning of PTEs contaminated sites utilizing hyperaccumulator plants.

Foliar applied titanium dioxide nanoparticles (TiO2 NPs) modulate growth, physiological and phytochemical traits in Melissa officinalis L. under various light intensities

Lemon balm (Melissa officinalis L.) is a valuable medicinal plant belonging to the mint family Lamiaceae with different uses in the food, cosmetic-hygienic, and pharmaceutical industries. Therefore, it is crucial to identify novel factors affecting growth, yield, and phytochemical compounds of this plant. In the current study, titanium dioxide (TiO2) nanoparticles (NPs) were foliarly applied at different concentrations (0, 50, and 100 mg L−1) following various light intensities (full (control), 75% and 50% sunlight) on lemon balm in a factorial experiment based on randomized complete block design (RCBD) with three replications (n = 3) for two continues years. IAnalytical techniques, SEM and EDX analyses, confirmed the uptake of TiO2 NPs through aerial parts of plant. Output of shoot dry weight, chlorophyll a (Chl-a) content, and total Chl and relative water content (RWC) were at their highest levels on plants grown at 50% light intensity upon foliar application of TiO2 NPs (100 mg L−1) in both years. High shading (50% of light intensity) without TiO2 NPs application markedly reduced EO content (by 60%), when compared to full solar radiation and exposure to TiO2 NPs (at 50 and 100 mg L−1) during two experimental years. Neral and geranial were the two main components of EO, with 30.7% and 45.05% in the first year of experiment, followed by 30.24% and 43.03% in full light intensity under 100 mg L−1 TiO2 NPs applications in the second year, respectively. Thus, a relatively shady environment and 100 mg L−1 TiO2 NPs foliar spray are recommended to attain a higher yield in lemon balm plants. Key findings of this study revealed the beneficial effects of high light intensity with TiO2 NPs foliar spray to improve the quality and quantity output of EO rich in neral and geranial constituents.

Teucrium fruticans L., a Multi-Scale Study: From Trichomes to Essential Oil.

This work represents the first multi-scale study on Teucrium fruticans L. cultivated at the Ghirardi Botanic Garden (Lombardy, Northern Italy), combining a micromorphological and a phytochemical survey on the plant's aerial parts. Micromorphological investigations, performed by Light Microscopy, Fluorescence Microscopy and Scanning Electron Microscopy, highlighted the presence of five trichomes morphotypes, distinguished by a different distribution pattern: peltates, short-stalked and ball-like medium-stalked capitates, ubiquitous on the whole plant, medium-stalked and long-stalked capitates, exclusive to the floral whorls. Both peltates and medium-stalked capitates were recognized as the main terpene production sites. Phytochemical characterization focused on the essential oils (EOs), obtained by Clevenger-type hydrodistillation in February and April 2022 and characterized by Gas Chromatography-Mass Spectrometry (GC/MS), which resulted mainly formed by sesquiterpene hydrocarbons. The February EO profile was characterized by β-caryophyllene (28.30 %) and germacrene D (19.16 %) as main compounds, while in April β-myrcene was detected at high percentage (13.77 %), in addition to the previous two components (15.72 % and 11.55 %, respectively). Literature data, dealing with the biological activities of the main oil constituents, highlighted an anti-microbial, anti-inflammatory, and anti-tumor potential, due to the high content in sesquiterpenes and, particularly, of β-caryophyllene and germacrene D.

Identification and pathogenicity of Nigrospora sphaerica and Curvularia penniseti associated with leaf spot disease of cowpea (Vigna unguiculata (L.) Walp.) in Nigeria

Pathogenic fungi are one of the main causes of plant diseases due to their ability to colonise plants and rapidly spread disease. Cowpea is one of the most highly consumed grain legumes in Nigeria, but its yearly production is usually affected by fungi attacks. Disease presenting browning of the aerial parts of the cowpea plant was observed during the dry season between 2021 and 2022 in the country. This disease caused stunted growth in the affected plant stand. The fungi were isolated from the symptomatic aerial parts. The fungi were viewed under the microscope and identified by molecular and phylogenetic tools using the Internal Transcribed Spacer (ITS) gene region. The fungi isolated from the symptomatic aerial part of cowpea were identified as Nigrospora sphaerica and Culvularia penniseti. The pathogenicity of the isolated fungi was tested on detached leaves and stems and on intact cowpea seedlings. The test gave a positive result, which confirms the pathogenicity of the isolated fungi on the cowpea plant. This is the first report of N. sphaerica and C. penniseti infecting cowpea cultivated on farmland in Nigeria. Early detection of foreign fungi causing disease in the country’s cowpea crop will aid researchers in addressing the negative effects on crop yield.

Triterpenoids of Three Apple Cultivars-Biosynthesis, Antioxidative and Anti-Inflammatory Properties, and Fate during Processing.

Triterpenoids are a group of secondary plant metabolites, with a remarkable pharmacological potential, occurring in the cuticular waxes of the aerial parts of plants. The aim of this study was to analyze triterpenoid variability in the fruits and leaves of three apple cultivars during the growing season and gain new insights into their health-promoting properties and fate during juice and purée production. The identification and quantification of the compounds of interest were conducted using gas chromatography coupled with mass spectrometry. The waxes of both matrices contained similar analytes; however, their quantitative patterns varied: triterpenic acids prevailed in the fruits, while higher contents of steroids and esterified forms were observed in the leaves. The total triterpenoid content per unit area was stable during the growing season; the percentage of esters increased in the later phases of growth. Antioxidative and anti-inflammatory properties were evaluated with a series of in vitro assays. Triterpenoids were found to be the main anti-inflammatory compounds in the apples, while their impact on antioxidant capacity was minor. The apples were processed on a lab scale to obtain juices and purées. The apple purée and cloudy juice contained only some of the triterpenoids present in the raw fruit, while the clear juices were virtually free of those lipophilic compounds.

Antioxidant activities in relation to the transport of heavy metals from the soil to different parts of Betula pendula (Roth.)

BackgroundBirch is a tree with a common occurrence in the environment and its organs are used in the form of herbal material. An important aspect of this study is birch pollen, which is a problem for allergy sufferers, and due to a variety of environmental conditions, its allergenicity may increase. Among the organs studied, inflorescences deserve attention, which, as seen from an overview of the literature, are analysed for the content of heavy metals for the first time in this study.ResultsThis paper investigated the relationship between antioxidant properties and the content of heavy metals (Cu, Zn, Cd, Pb, Ni and Cr) as the plant's response to stress, taking into account both the vegetative and generative organs of the tree Betula pendula. While studying the accumulation of elements in individual organs, the research was extended to include the aspect of different environmental conditions, reflected in two soil types of differing physicochemical properties: sandy and silty soils. In order to thoroughly analyse the transport of the studied heavy metals from the soil to individual organs (leaves, inflorescences and pollen), ecotoxicological indicators were used. A modified translocation factor (TF) index into sTF (sap translocation factor) was presented as a novelty in research, calculated based on the content of selected heavy metals in the sap flowing to individual birch organs. This allowed for a more complete description of the transport of elements in the aerial parts of plants, indicating the accumulation of zinc and cadmium, especially in leaves. Among the studied environmental conditions which may affect the accumulation of heavy metals, sandy soil is of particular significance, conditioning lower pH values, among other things. However, analysis of the reaction of birch to the conditions of the soil environment and the content of heavy metals, based on antioxidant properties, demonstrated an evident reaction to stress, but without an unambiguous response among the studied vegetative and generative organs.ConclusionsAs birch is a plant with wide utility values, monitoring studies are advisable to exclude the risk of accumulation of heavy metals in its organs, and for this purpose it may be useful to use the sTF indicator and assess the antioxidant potential.

New insight into the mechanisms of preferential encapsulation of metal(loid)s by wheat phytoliths under silicon nanoparticle amendment

Silicon nanoparticles (SiNPs) have been widely used to immobilize toxic trace metal(loid)s (TTMs) in contaminated croplands. However, the effect and mechanisms of SiNP application on TTM transportation in response to phytolith formation and phytolith-encapsulated-TTM (PhytTTM) production in plants are unclear. This study demonstrates the promotion effect of SiNP amendment on phytolith development and explores the associated mechanisms of TTM encapsulation in wheat phytoliths grown on multi-TTM contaminated soil. The bioconcentration factors between organic tissues and phytoliths of As and Cr (> 1) were significantly higher than those of Cd, Pb, Zn and Cu, and about 10 % and 40 % of the total As and Cr that bioaccumulated in wheat organic tissues were encapsulated into the corresponding phytoliths under high-level SiNP treatment. These observations demonstrate that the potential interaction of plant silica with TTMs is highly variable among elements, with As and Cr being the two most strongly concentrated TTMs in the phytoliths of wheat treated with SiNPs. The qualitative and semi-quantitative analyses of the phytoliths extracted from wheat tissues suggest that the high pore space and surface area (≈ 200 m2 g−1) of phytolith particles could have contributed to the embedding of TTMs during silica gel polymerization and concentration to form PhytTTMs. The abundant SiO functional groups and high silicate-minerals in phytoliths are dominant chemical mechanisms for the preferential encapsulation of TTMs (i.e., As and Cr) by wheat phytoliths. Notably, the organic carbon and bioavailable Si of soils and the translocation of minerals from soil to plant aerial parts can impact TTM sequestration by phytoliths. Thus, this study has implications for the distribution or detoxification of TTMs in plants via preferential PhytTTM production and biogeochemical cycling of PhytTTMs in contaminated cropland following exogenous Si supplementation.

First Report of Lasiodiplodia theobromae Causing Dieback Symptoms on Plantain (Musa AAB subgroup) in Nigeria.

Bananas (banana and plantains) rank sixth among staple food crops (FAO 2018), with production challenged by biotic factors, mainly fungal diseases that may cause a total loss in some orchards (Jones 2018). In April 2017, dieback symptoms (progressive blackening and necrotic aerial plant parts, leaves, fruits and peduncles) were observed on plantain (Musa AAB subgroup), in Onne, Rivers State, Nigeria (4°42'55.4012″N, 7°10'35.92128″E). Diseased plants (n=112) were either wilted with blackened necrotic areas, or dead (Fig. S1). Nearly 10% of the plants had blackened pseudostems and fruits with slate gray to black internal tissues when sliced (Fig. S1) and black, erumpent pycnidia were observed on diseased fruits. A fungal species was consistently isolated when surface disinfected pieces of diseased samples were cultured on PDA plates. Plates were incubated at 25±2°C for 4 to 15 d to observe conidia. Isolates had colonies and conidia consistent with members of the Botryosphaeriaceae family (Phillips et al. 2013). Immature conidia were single-celled, ellipsoidal and hyaline while mature conidia were two-celled, had a thick wall, a central septum, longitudinal striations, and a dark brown, cinnamon-like color. Size of mature conidia (n = 20) ranged 22.9 to 30.0 × 14.2 to 18.4 μm ( = 27.0 × 15.6 μm; Fig. S1). DNA templates of three isolates (23688-2_R16; 19144-18_R15 and PITA_22-1) were amplified using primers ITS1 and ITS4 for the ITS locus, EF1-688F and EF1-1251R for the translation elongation factor 1-α (TEF-1α) locus (Phillips et al. 2013) and sequenced (GenBank accession Nos. MZ413346, MZ413347, and MZ413348 for ITS; and MZ420177, MZ420178, and MZ420179 for TEF-1α). BLASTn query showed 100% identity with reference sequences of various isolates of Lasiodiplodia theobromae. Based on morphological characters and nucleotide homology, the isolates were identified as L. theobromae (Fig. S1 & S2). To fulfil Koch's postulates, 4-month-old plants of plantain hybrid PITA 24, and mature fruits from three genotypes (PITA 24, plantain cultivar Obino L'ewai) were inoculated with mycelial plugs from the margins of 5-d-old cultures of the three L. theobromae isolates. Pseudostems were drilled with a sterile 5 -mm cork borer, a mycelial plug placed down into the wound, covered with sterilized cotton, and sealed with parafilm. Sterile water was injected every third day to maintain moisture at the inoculated area. Toothpicks containing mycelia were used to inoculate fruits, placed in plastic Crisper boxes. Sterile PDA plugs or toothpicks were used for the controls. Inoculated plants and fruits were kept in a screenhouse at room temperature (~26°C) for 14 d. All inoculated materials developed symptoms similar to the diseased plants in the field. Control plants and fruits remained asymptomatic. L. theobromae was re-isolated from the artificially inoculated plant parts and its identity was confirmed. The fungus L. theobromae is distributed in tropical and subtropical regions and has a wide host range (Phillips et al. 2013; Mehl et al. 2017). This fungus was previously reported in grey literature as the causal agent of Musa spp. basal rot at Onne, Nigeria (Mwangi et al. 2005) but its molecular identification was not conducted; it was unknown whether the isolates were indeed L. theobromae or other cryptic species (L. pseudotheobromae or L. parva) (Alves et al. 2008). Over 15 years later, the present study confirms L. theobromae as the causal agent of basal rot of bananas based on nucleotide homology, and to our knowledge, this is the first report of L. theobromae causing dieback disease on plantain in Nigeria and in Africa. There is need to conduct a more comprehensive distribution surveys and develop appropriate control strategies in Nigeria.

Essential oil composition and antimicrobial activity of Glaucosciadium cordifolium (Boiss.) Burtt. & Davis

Glaucosciadium cordifolium (Boiss.) Burtt. & Davis, which is a monotypic species naturally grown in Turkey belonging to the Apiaceae (Umbelliferae) family. In this study, the essential oil obtained from G. cordifolium was analyzed and evaluated for its antimicrobial effects. In chemical studies, the analyzes of essential oil compounds obtained from the aerial parts of plants by hydrodistillation were carried out with GC-FID and GC-MS. In total, 23 compounds were identified making up 98.7% of the total volatile constituents. Sabinene (42.1%), α-pinene (17.1%), and α-phellandrene (10.1%) were found as the main constituents in the oil. In antimicrobial studies, the anticandidal and antibacterial effects of essential oils were tested against 14 pathogenic microorganisms according to the standard protocols of the Clinical Laboratory Standards Institute (CLSI). It has been determined that essential oils have a very weak inhibitory effect when compared with standard antibacterial agents. MIC values of 1800, 3600 µg/Ml, and higher were determined. In addition, it was determined that it showed inhibitory effects, especially against C. krusei at a concentration of 250 µg/mL, with MIC values ranging from 250 to 2000 µg/mL.

Rubia cordifolia L. Crude Aerial Part Extracts Show a High Potential as Antimalarials against Chloroquine Resistant Plasmodium falciparum Strains in vitro

Pharmacognosy Research,2023,15,2,288-296.DOI:10.5530/pres.15.2.031Published:February 2023Type:Original Article Authors:Magara Jeremiah, Lucy Kamau, Grace Nyambati, and Hastings Ozwara Author(s) affiliations:Magara Jeremiah1, Lucy Kamau1, 2,*, Grace Nyambati3, Hastings Ozwara4 1Department of Zoological Sciences, Kenyatta University, Nairobi, KENYA. 2Department of Animal Sciences, Kenyatta University, Nairobi, KENYA. 3Department of Biomedical Sciences and Technology, The Technical University of Kenya, Nairobi, KENYA. 4Department of Tropical and Infectious Diseases, Institute of Primate Research, Nairobi, KENYA. Abstract:Introduction: Plasmodium falciparum human malaria parasite is resistant to most available medicines in Africa, necessitating research for new drugs. Rubia cordifolia L. is used in traditional malaria treatment in Kenya despite no supporting scientific data. Objectives: To evaluate anti-plasmodial efficacy of extracts from the aerial part of Rubia cordifolia against chloroquine sensitive (3D7) and resistant (W2) Plasmodium falciparum strains. Methods: Hexane, methanol and water were separately used in crude extractions from open shade dried aerial plant parts. Phytochemical composition was determined qualitatively. Anti-plasmodial efficacy of serial dilutions (range; 0.4 to 50 μg/ml) of each extract were evaluated in vitro and compared using ANOVA and Tukey’s HSD test, at p<0.05). Results: All the extracts significantly inhibited parasites growth, in a dose dependent manner. At 50 μg/ml, inhibition was (84.07%, 77.94% and 66.08%) for hexane, methanol and water extracts respectively against W2 and (80.06%, 78.36% and 60.92%) against 3D7 strain. Hexane extract showed IC50 0.551 μg/ml and 2.747 micrograms/ml against W2 and 3D7 respectively. Methanol extract, IC50 1.231 and 3.528 μ g/ml respectively, aqueous extract showed moderate activity, IC50 5.348 μg/ml and 17.341 μg/ml against the strains respectively. Chloroquine resistant (W2 strain) was more responsive to the extracts than 3D7 strain. Conclusion: Anti-plasmodial activities were in the order, Hexane>methanol>aqueous and were attributed to the phytochemicals present in the extracts. This presents evidence of R. cordifolia as anti-malarial drugs’ source. Further work is required to identify, purify, and characterize active molecules for development of anti-malaria drugs. Keywords:Antimalarial activity, Crude extracts, in vitro, Plasmodium falciparum, Rubia cordifolia.View:PDF (236.96 KB)

Enrichment and distribution characteristics of heavy metal(loid)s in native plants of abandoned farmlands in sewage irrigation area.

Soil samples and native plants were collected from abandoned farmlands with a long history of sewage irrigation along Dongdagou stream, Baiyin City. We investigated the concentrations of heavy metal(loid)s (HMMs) in soil-plant system to evaluate the accumulation and transportation ability of HMMs in native plants. Results indicated that soils in study area were severely polluted by Cd, Pb, and As. With the exception of Cd, the correlation between total HMM concentrations in soil and plant tissues was poor. Among all investigated plants, no one was close to the criteria for the HMM concentrations of hyperaccumulators. The concentrations of HMMs in most plants were reached the phytotoxic level and the abandoned farmlands could not be used as forages, which showed that native plants may possess resistance capabilities or high tolerance for As, Cu, Cd, Pb, and Zn. The FTIR (Fourier transform infrared spectrometer) results suggested that the detoxification of HMMs in plants may depend on the functional groups (-OH, C-H, C-O, and N-H) of some compounds. Bioaccumulation factor (BAF), bioconcentration factor (BCF), and biological transfer factor (BTF) were used to identify the accumulation and translocation characteristics of HMMs by native plants. S. glauca had the highest mean values of BTF for Cd (8.07) and Zn (4.75). C. virgata showed the highest mean BAFs for Cd (2.76) and Zn (9.43). P. harmala, A. tataricus, and A. anethifolia also presented high accumulation and translocation abilities for Cd and Zn. High HMMs (As, Cu, Cd, Pb, and Zn) accumulation in the aerial parts of plants may lead to increased accumulation of HMMs in the food chain; additional research is desperately required. This study demonstrated the HM enrichment characteristics of weeds and provided a basis for the management of abandoned farmlands.

Morphogenesis at the shoot meristem.

Shoot apical meristems are populations of stem cells which initiate the aerial parts of higher plants. Work during the last decades has revealed a complex network of molecular regulators, which control both meristem maintenance and the production of different types of organs. The behavior of this network in time and space is defined by the local interactions between regulators and also involves hormonal regulation. In particular, auxin and cytokinin are intimately implicated in the coordination of gene expression patterns. To control growth patterns at the shoot meristem the individual components of the network influence directions and rates of cell growth. This requires interference with the mechanical properties of the cells. How this complex multiscale process, characterized by multiple feedbacks, is controlled remains largely an open question. Fortunately, genetics, live imaging, computational modelling and a number of other recently developed tools offer interesting albeit challenging perspectives.

Responses of Aerial and Belowground Parts of Different Potato (Solanum tuberosum L.) Cultivars to Heat Stress

The mechanism of potato (Solanum tuberosum L.) thermotolerance has been the focus of intensive research for many years because plant growth and tuber yield are highly sensitive to heat stress. However, the linkage between the aerial and belowground parts of potato plants in response to high temperatures is not clear. To disentangle this issue, the aerial and belowground parts of the heat-resistant cultivar Dian187 (D187) and the heat-sensitive cultivar Qingshu 9 (Qs9) were independently exposed to high-temperature (30 °C) conditions using a special incubator. The results indicated that when the belowground plant parts were maintained at a normal temperature, the growth of the aerial plant parts was maintained even when independently exposed to heat stress. In contrast, the treatment that independently exposed the belowground plant parts to heat stress promoted premature senescence in the plant's leaves, even when the aerial plant parts were maintained at a normal temperature. When the aerial part of the plant was independently treated with heat stress, tuberization belowground was not delayed, and tuberization suppression was not as severe as when the belowground plant parts independently underwent heat stress. Heat stress on the belowground plant parts alone had virtually no damaging effects on the leaf photosynthetic system but caused distinct tuber deformation, secondary growth, and the loss of tuber skin colour. Transcriptome analysis revealed that the treatment of the belowground plant parts at 30 °C induced 3361 differentially expressed genes in the Qs9 cultivar's expanding tubers, while the D187 cultivar had only 10,148 differentially expressed genes. Conversely, when only the aerial plant parts were treated at 30 °C, there were just 807 DEGs (differentially expressed genes) in the D187 cultivar's expanding tubers compared with 6563 DEGs in the Qs9 cultivar, indicating that the two cultivars with different heat sensitivities have distinct regulatory mechanisms of tuberization when exposed to heat stress. The information provided in this study may be useful for further exploring the genes associated with high-temperature resistance in potato cultivars.