Lavender Plants Research Articles

Efeitos de tratamentos com nanopartículas e estresse salino na estrutura genética e características fisiológicas de Lavandula angustifolia Mill.

Lavandula angustifolia Mill. is an aromatic herb of the Lamiaceae family, which has been widely used by humans for many centuries. In the current study, we treated L. angustifolia samples with various concentrations of ZnO and Fe2O3 nanoparticles in the presence/ absence of NaCl salinity stress to evaluate the composition of essential oils, genetic structure, glandular trichome density and cellular Zn2+ and Fe2+ contents. We used Inter Simple Sequence Repeat (ISSR) molecular markers to investigate the parameters of genetic diversity among the treated samples. Furthermore, the hydro-distilled essential oil from the aerial parts of the samples was subjected to GC and GC / MS analyses. SPSS ver. 15, PAST, PopGene, and GenAlex software were employed for statistical analyses. Intracellular concentrations of Fe2+ and Zn2+ differed under various concentrations of nanoparticles and salinity treatments, and a significant negative correlation was observed between these elements, however, nanoparticles treatment significantly increased intracellular concentrations of iron and zinc ions. We found four types of glandular trichomes on the surface of the leaf of the treated plants, and the ANOVA test revealed a significant variation for most of them. Meanwhile, the short-stalked capitate trichomes were the most frequent in most of the evaluated samples. The main and trace essential oil compounds were the same among the treated plants, meanwhile, their percentages varied among the samples. The percentages of 1,8- cineole and camphor decreased in treated plants, which affects the quality of essential oils. Parameters of genetic diversity differed among the treated samples. Furthermore, the AMOVA test demonstrated a significant genetic variation that its substantial part belonged to among treated samples. These findings revealed that the treatment of nanoparticles and salinity stress strongly influenced the genetic diversity, trichomes density, iron and zinc ions content in lavender plants.

Metabolomic Profile and Biological Properties of Sea Lavender (Limonium algarvense Erben) Plants Cultivated with Aquaculture Wastewaters: Implications for Its Use in Herbal Formulations and Food Additives.

Water extracts from sea lavender (Limonium algarvense Erben) plants cultivated in greenhouse conditions and irrigated with freshwater and saline aquaculture effluents were evaluated for metabolomics by liquid chromatography-tandem high-resolution mass spectrometry (LC-HRMS/MS), and functional properties by in vitro and ex vivo methods. In vitro antioxidant methods included radical scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), ferric-reducing antioxidant power (FRAP), and copper and iron chelating assets. Flowers’ extracts had the highest compounds’ diversity (flavonoids and its derivatives) and strongest in vitro antioxidant activity. These extracts were further tested for ex vivo antioxidant properties by oxidative haemolysis inhibition (OxHLIA), lipid peroxidation inhibition by thiobarbituric acid reactive substances (TBARS) formation, and anti-melanogenic, anti-tyrosinase, anti-inflammation, and cytotoxicity. Extract from plants irrigated with 300 mM NaCl was the most active towards TBARS (IC50 = 81 µg/mL) and tyrosinase (IC50 = 873 µg/mL). In OxHLIA, the activity was similar for fresh- and saltwater-irrigated plants (300 mM NaCl; IC50 = 136 and 140 µg/mL, respectively). Samples had no anti-inflammatory and anti-melanogenic abilities and were not toxic. Our results suggest that sea lavender cultivated under saline conditions could provide a flavonoid-rich water extract with antioxidant and anti-tyrosinase properties with potential use as a food preservative or as a functional ingredient in herbal supplements.

Chemical Composition and Assessment of Antimicrobial Activity of Lavender Essential Oil and Some By-Products.

The producers of essential oils from the Republic of Moldova care about the quality of their products and at the same time, try to capitalize on the waste from processing. The purpose of the present study was to analyze the chemical composition of lavender (Lavanda angustifolia L.) essential oil and some by-products derived from its production (residual water, residual herbs), as well as to assess their “in vitro” antimicrobial activity. The gas chromatography-mass spectrometry analysis of essential oils produced by seven industrial manufacturers led to the identification of 41 constituents that meant 96.80–99.79% of the total. The main constituents are monoterpenes (84.08–92.55%), followed by sesquiterpenes (3.30–13.45%), and some aliphatic compounds (1.42–3.90%). The high-performance liquid chromatography analysis allowed the quantification of known triterpenes, ursolic, and oleanolic acids, in freshly dried lavender plants and in the residual by-products after hydrodistillation of the essential oil. The lavender essential oil showed good antibacterial activity against Bacillus subtilis, Pseudomonas fluorescens, Xanthomonas campestris, Erwinia carotovora at 300 μg/mL concentration, and Erwinia amylovora, Candida utilis at 150 μg/mL concentration, respectively. Lavender plant material but also the residual water and ethanolic extracts from the solid waste residue showed high antimicrobial activity against Aspergillus niger, Alternaria alternata, Penicillium chrysogenum, Bacillus sp., and Pseudomonas aeroginosa strains, at 0.75–6.0 μg/mL, 0.08–0.125 μg/mL, and 0.05–4.0 μg/mL, respectively.

First Report of Blackleg DiseaseCaused by Epicoccum sorghinumon on Lavender (Lavandula stoechas) in China.

Lavender (Lavandula angustifolia Mill) is an ornamental plant and worldwidely grown for its aromatic and pharmacological qualities. In June 2020, the symptoms of blackleg disease on lavender plants were observed, with more than 50% incidence in Chaohu city (117°38'19.12″N, 31°47'18.94″W) of Anhui Province, China. The disease symptoms progressed from stem wilt and necrosis to prolonged necrosis and bending of leaves, and all infected lavender plants died eventually. Ten necrotic stem lesions werecollectedfrom ten independent plants for the isolation of pathogen. All samples were washed in 70% ethanol for 1 minute, rinsed twice in sterile distilled water and placed on water agar (WA) plates containing 30 mg/liter of kanamycin. All 16 fungal isolates were transferred onto potato dextrose agar (PDA) and incubated at 26°C for 5 days, and all fungal colonies were isolated consistently, which produced redish-gray mycelium at 26°C with a 12-h photoperiod on PDA media. They developed black pycnidia with abundant hyaline, unicellular, oval shaped conidia (4.5 to 5.9 × 2.1 to 2.5 μm) after 14 days. DNA was extracted (10-day-old culture) using the Fungal DNA Mini Kit (Omega Bio-tek, China), according to the manufacturer's protocol. The internal transcribed spacer (ITS), beta-tubulin (β-tub) and translation elongation factor 1-alpha (tef1-α) genes of three isolates were amplified using the primers: ITS1/ITS4 (White et al. 1990), Bt2a/Bt2b (Glass et al. 1995) and EF1-728F/EF1-986R (Carbone et al. 1999), respectively. The ITS(MT883331), β-tub(MT896891) andtef1-α (MT874165) genes were sequenced and analyzed through BLASTn. The ITS sequence showed 99.81% with Epicoccum sorghinum (GenBank Accession No. MK020690.1). The β-tub and tef1-α showed 100% homology with Epicoccum sorghinum (GenBank AccessionMN554062.1 and MN512426.1), respectively. To complete Koch's postulates, pathogenicity tests were performed by spraying the fungal spore suspension (1×105 CFU/ml) prepared from 14-day-old cultures onto needling wounded stems of 1-year-old potted healthy L. angustifolia plants. The healthy plants were sprayed with sterilized water onto needling wounded stems served as negative control. Wilting and stem necrosis were observed 5 days afterinoculation and incubation in a growth chamber at 26°C, with a 12-h photoperiod. All fungal infected plants died after 10 days, while, the control plants remained healthy. The fungus was re-isolated from the lesions of the inoculated plants and verified. Based on morphological characteristics, sequence analysis and pathogenicity test, the pathogen was identified as E. sorghinum. The pathogen has been observed previously on many plants such as tea (Bao et al. 2019) and taro (Liu et al. 2018), in China. To our knowledge, this is the first report of E. sorghinum causing blackleg disease of lavender in China and worldwide.

EFFECT OF CHICKEN MANUREFERTILIZATION, ACTIVE DRY YEAST FOLIAR SPRAY CONCENTRATIONS AND THEIR INTERACTION ON LAVANDER (LAVANDULA OFFICINALIS, CHAIX) PLANTS GROWTH AND PRODUCTIVITY

A field experimental laid out at a completely randomized block design at the experimental farm of Fac. of Environ. Agric. Sci., Arish Univ., El-Arish, North Sinai Governorate, Egypt during the two successive summer seasons of 2017/2018 and 2018/2019, to study the effect of chicken manure (ChM) as N fertilizer source, dry yeast spraying concentrations and their interaction on vegetative, yield and chemical composition of lavender (Lavandula officinalis). Results showed that fertilization lavender plants with 100 % from the recommended N rate as chicken manure (ChM) recorded the maximum growth, yield and chemical constitutes of lavender. Moreover, application of dry yeast at 200 ppm increased significantly lavender growth, yield and chemical constitutes. For the interaction between chicken manure (ChM) as N fertilizer source and dry yeast concentrations the same trend were observed when plants fertilized with 100 % from the recommended N rate as chicken manure (ChM) and sprayed with 200ppm dry yeast.

INFLUENCE OF CHITOSAN AND MICRONUTRIENTS (FE + ZN) CONCENTRATIONS ON GROWTH, YIELD COMPONENTS AND VOLATILE OIL OF LAVENDER PLANT

To study the influence of the two factors of chitosan concentration (0.0, 100, 200 and 400 ppm), micronutrients as FeSO4 + ZnSO4 (0.0, 50, 100 and 200 ppm) and their combination treatments on plant growth, yield components, volatile oil production, total carbohydrates % and total chlorophyll content (SPAD unit), two filed experiments were conducted on lavender (Lavandula officinalis, Chaix.) during the two summer consecutive seasons of 2018 and 2019 at Agric. Res. Farm, Fac. Agric., Zagazig Univ., Egypt. The Experimental layout was split-plot design between the four chitosan concentrations as main plots and the four micronutrients concentration as sub-plots in randomized complete blocks design with 3 replicates. The obtained results referred to that using chitosan concentration of 400 ppm significantly increased growth parameters (plant height, number of branches/plant, fresh and dry weights of roots/plant as well as root number and length), yield components (total dry herb yield/plant and /feddan), volatile oil production (volatile oil percentage and volatile oil yield per plant) and chemical constituents (total chlorophyll content and total carbohydrates percentage) compared to control and the other levels under study. Furthermore, the highest values in these characters were noticed by micronutrients at 200 ppm treatment in both seasons, in most cases. In general, it is preferable to spray lavender plants with chitosan at 400 ppm combined with Fe + Zn at 200 ppm five times a season to increase the plant growth, yield components and plant pigments as well as volatile oil production of this important aromatic plant

Agroecological approach to quality assessment of organic aromatic products

The developed complex scientific-methodical approach to the survey of organic agricultural enterprise was presented in order to confirm the quality of aromatic products of the “Organic” class. The analysis of agrochemical soils indicators was performed for the first time, which were cultivated according to organic technology for eleven years. It was proven that long-term use of organic farming contributes to the preservation and improvement of soil fertility. An elemental biomass analysis of the apical part of lavender plants grown by organic method was carried out, from which the essential oil was then obtained. It was confirmed that the essential oil composition depends on the place of its production and on the soil characteristics on which the plants were grown. The elemental analysis of essential oil showed that there is an intensive carry-over of all major macro- and micronutrients from the soil into plants during their growth and development. In the lavender essential oil, there are more than 50 substances that determine its uniqueness. Therefore, to confirm the quality of “Organic” class products, we propose to conduct a comprehensive assessment of all components of the organic production system “soil — plant — products”. Thermal analysis, electron microscopy with detectors for energy dispersion analysis, chromatographic analysis, potentiometry, flame photometry and chemical analytical methods were used for the research. Differences in quality indicators of organic essential oil and oil obtained with the traditional farming method were revealed. The study found that the produced lavender oil is a unique quality product grown in an organic way. At present, quality management of agricultural products is possible subject to specialists' availability in the agro-industrial complex with competence in the field of chemical-toxicological and environmental analysis knowing methods to determine the quality and safety of agricultural products, including organic products.

Growth and development of narrow-leaved lavender plants depending on methods of reproduction, planting time and technological measures.

Growth and development of narrow-leaved lavender plants depending on methods of reproduction, planting time and technological measures.

EFFECT OF ORGANIC AND BIO-FERTILIZERON GROWTH, YIELD, AND ESSENTIAL OIL OF LAVANDULA OFFICINALIS L. PLANT GROWN IN TO SANDY SOIL

Lavender (Lavandula officinalis L) has high economic and medicinal value. The current experiment was carried out during the two successive seasons 2018/2019 and 2019/2020. It aimed to investigate the effect of compost, biofertilizers (Azospirillum spp., Azotobacter spp.), mixtures of them, and active dry yeast on vegetative and chemical composition of lavender herbs cultivated on plastic pots filled with sandy soil. Fertilizers were added to the plant roots three times during the growing seasons. Growth and yield characteristics were quantitatively assessed and were compared to each other. Lavender essential oil percentage was determined from the fresh herb, as well as the oil constituents to assess the oil quality. Moreover, the study was tailed by an economic assay to determine the study feasibility. Results indicated that application of biofertilizers significantly increased plant height, number of branches, fresh weight, dry weight, yield, % essential oils, N, P, K%, crude protein content, total pigment, antioxidant, flavonoid, phenol, total carbohydrates, and free amino acids contents compared with the control treatment. Mixtures of bacteria (Azotobacter, Azospirillum) treatments were the superior in all measured variables. It also increased the percentage of essential oils. The main essential oils (EO) constituents were linalool, linalyl acetate, borneol, terpinen4-ol, and 1,8-cineole. From the economic point of view, also the biofertilizer treatments were feasible, this could result in environmentally safe plants to minimize the hazards of pollution caused by using mineral fertilizers. The economic evaluation indicated that mixtures of bacteria resulted in the highest value of net return for lavender plants.

Frost resistance, shoots, scale, damage index, bark, cambium, wood, core.

Aim. The article aimed at investigation of low temperatures affects features on lavender (Lavandula angustifolia Mill.) cultivars of different ages to determine the possibility of the spread of crop areas in the soil-climatic zones of the Forest-Steppe and Polissya of Ukraine. Methods. The influence of low temperatures on the structural parts of shoots of lavender plants of narrow-leaved cultivars ‘Prima’, ‘Record’ and ‘2-56’ grown in the conditions of the Forest-Steppe of Ukraine in the collection nursery of the Institute of Horticulture of the National Academy of Sciences of Ukraine is analyzed. Critical temperature indices (–25ºC and –30ºC), determined by three-year studies on the structure of lavender plants of the green bark (bark, cambium, wood and core). Results. It was found that one-year shoots were the most damaged by low temperatures – from 2.5 to 4.5 points on a 6-point scale, the least – two and three-year from 0.8 to two points. The most resistant to low temperatures in the average of three years of research were plants of sample ‘2-56’, which had been transferred to the State cultivar testing under the name ‘Mriya’, which total damage rate reached 11.3%. The record-resistant plants were the least resistant to low temperatures, indicating their low adaptive capacity to uncharacteristic growing conditions. The –30ºC temperature regime on the structural units of two- and three-year-old ‘Prima’ and ‘Mriya’ had the most significant negative impact. The objects of research were the most damaged by low temperatures of bark and cambium – up to 3.5 points. The smallest core – up to 2.5 points was seen (except for the ‘Record’ cultivar, all structural units damaged up to 4.5 points). It has been determined that the frost resistance of narrow-leaved lavender plants was a high-grade genetically fixed trait that could be improved as a result of breeding work. Conclusions. The research shows that the structural units of the plants of all the cultivars that were in the experiment did not reach the damage index 400, which destroys the plant, as well as the mark 100 for individual structural units, indicating less or more endurance of narrow-leaved lavender plants under the conditions of forest-steppe cultivation in the Kyiv region. According to the research, the cultivars ‘Prima’ and ‘Mriya’ could be recommended for introduction in the Forest-Steppe of Ukraine, as well as the Polissya zone. ‘Record’ cultivar plants could be used as a source of high levels of decorative and essential oil content.

Insects on lavender in Isparta province, Turkey

Since ancient times, people have been interested in parfumed and spicy plants and used them in many areas such as cosmetics, flavors, foodstuffs and dyes. The effects of plant extracts and essential oils derived from these plants on plant diseases and pests have been studied in detail for many years. The lavender is becoming one of the most important aromatic plants in Isparta province and there has recently been an increase in lavender plantations. However, there is limited or no any study on pests of lavender in Turkey. This study aimed at identifying insect that attack to lavender plants. The surveys were performed in two locations of Isparta province in Turkey between 2015-2016. The Insects on lavander plants were sampled by three different methods (sweep net, pitfall and direct plant sampling). The collected insects’ samples were brought to the laboratory in the plastic containers. Once morphologically identified, the insects were sent to the authorities for species identification. As a result, some insects belonging to different orders (Orthoptera, Hemiptera, Coleoptera, Diptera, Lepidoptera, Hymenoptera) were determined. Poecilimon glandifer Karabağ (Orthoptera: Tettigoniidae), Cercopis vulnerata Rossi (Hemiptera: Cercopidae), Lepyronia coleoprata (L.), Neophilaenus lineatus (L.), Philaenus spumarius (L.), Philaenus spumarius (L.) (Hemiptera: Aphrophoridae), Atrococcus achillae (Kiritchenko) (Hemiptera: Pseudococcidae) were found to be the most common pest species in sampled lavender plants.

Effect of AuNPs and AgNPs on the Antioxidant System and Antioxidant Activity of Lavender (Lavandula angustifolia Mill.) from In Vitro Cultures.

The aim of this study was to determine the effect of gold and silver nanoparticles on the activity of antioxidant enzymes (ascorbate peroxidase (APX), superoxide dismutase (SOD), guaiacol peroxidase (POX), and catalase (CAT)), the free radical scavenging capacity, and the total polyphenol capacity of lavender (Lavandula angustifolia Mill.) cultivar “Munstead” propagated in vitro. In the experiment, fragments of lavender plants were cultivated in vitro on medium with the addition of 1, 2, 5, 10, 20, and 50 mg∙dm−3 of AgNPs or AuNPs (particle sizes 24.2 ± 2.4 and 27.5 ± 4.8 nm, respectively). It was found that the nanoparticles increase the activity of the antioxidant enzymes APX and SOD; however, the reaction depends on the NP concentration. The highest APX activity is found in plants propagated on media with 2 and 5 mg∙dm−3 of AgNPs. AuNPs significantly increase the APX activity when added to media with a concentration of 10 mg∙dm−3. The highest SOD activity is recorded at 2 and 5 mg∙dm−3 AgNP and AuNP concentrations. The addition of higher concentrations of nanoparticles to culture media results in a decrease in the APX and SOD activity. The addition of AuNPs to culture media at concentrations from 2 to 50 mg∙dm−3 increases the POX activity in comparison to its activity when AgNPs are added to the culture media. No significant influence of NPs on the increase in CAT activity was demonstrated. AgNPs and AuNPs increased the free radical scavenging capacity (ABTS•+). The addition of NPs at concentrations of 2 and 5 mg∙dm−3 increased the production of polyphenols; however, in lower concentrations it decreased their content in lavender tissues.

Crescimento e fluorescência de alfazema submetida ao osmocondicionamento das sementes e à salinidade

A alfazema é uma espécie medicinal amplamente utilizada na medicina popular, especialmente na região Nordeste do Brasil. Contudo, seu crescimento pode ser limitado pelo excesso de sais na água utilizada na irrigação, sendo necessária a busca por alternativas que minimizem os efeitos. Assim, objetivou-se avaliar o condicionamento osmótico das sementes nas características de crescimento e fluorescência da clorofila ‘a’ em plantas de M. suaveolens sob estresse salino. O delineamento estatístico foi o de blocos casualizados em esquema fatorial incompleto 5x5 com cinco níveis de condutividade elétrica da água de irrigação (0,5; 1,45; 5,00; 8,55; e 10,0 dS m-1) e cinco potenciais osmóticos (0,0; -0,15; -0,50; -0,85; e -1,0 MPa), com quatro repetições constituídas de duas plantas, totalizando nove combinações geradas através da matriz Composto Central de Box. Foram avaliadas as características de crescimento e os parâmetros de fluorescência da clorofila ‘a’ aos 45 dias após o início da aplicação das águas salinas. Os dados foram submetidos aos testes de normalidade (Shapiro-Wilk) e de homogeneidade das variâncias (Bartlett). Após os dados terem atendido aos pressupostos, os mesmos foram submetidos à análise de variância pelo teste F, nos casos de significância foi realizada análise de regressão polinomial. As características de crescimento foram afetadas severamente pelo aumento da salinidade da água de irrigação. Salinidade acima de 3,9 dS m-1 reduz todos os parâmetros de fluorescência da clorofila a em plantas de alfazema brava. O osmocodicionamento das sementes com polietilenoglicol atenua os efeitos negativos da salinidade sobre a emissão de folhas. O condicionamento das sementes com PEG estimula a atividade dos índices de fluorescência da clorofila ‘a’.

Water structuring device for the quality improvement of aromatic plants Primary tabs

The paper presents the results of research aimed at improving the growth of aromatic plants and stimulating microbial communities in the rhizosphere of two test plants (Lavender and Rosemary), using a water structuring device (Alchewat). The experiments, started in November 2019, were conducted in the greenhouses of CREA-OF in Pescia (PT). The experimental groups were: i) group without structured water, irrigated with water and substrate previously fertilized; ii) group with structured water, irrigated with water and substrate previously fertilized. The test showed a significant improvement in the agronomic parameters analyzed in Lavender and Rosemary plants treated with structured water. In particular, all plants treated with structured water showed a significant increase in plant height, vegetative and roots weight, total flowers biomass and total microbial count. In addition, there was a significant reduction in Lavender of the number of plants dried in structured water treatment and a positive trend in Rosemary, but not significant. The results of this experiment are in accordance with literature and field observation data that report a beneficial effect of structured water on plant growth, health, quantity and quality of yields. Also very interesting is the increase in the substrate of the theses treated with structured water of the number of useful microorganisms, which are probably supporters of the improvement of plant growth. The presence of microorganisms in the substrate can also affect the biotic and abiotic stress resistance of plants. These aspects consequently become very interesting for the grower who can reduce the use of water and fertilizers and increase the quality of the plants by using alternative techniques.

First report of Xanthomonas hortorum causing bacterial leaf spot of lavender (Lavandula × intermedia) in Ohio.

In July 2018, a sample of lavender var. Grosso (Lavandula × intermedia 'Grosso') from Miami County, OH was received by The Ohio State University Vegetable Pathology Laboratory in Wooster. Lavender plants were field-grown in sandy clay soil with plastic mulch under drip irrigation. Disease incidence ranged from 0 to 32% depending on variety. Leaves and stems showed dark necrotic lesions that varied from roughly circular (ca. 0.3 to 0.5 mm diameter) to large coalesced necrotic areas surrounded by a water-soaked halo. Bacterial streaming from lesions was observed microscopically. Leaf tissue pieces (~0.5 cm2) were surface sterilized in 70% ethanol for 30 seconds and rinsed in sterile deionized water. The tissue was sliced aseptically into smaller sections in 100 μl sterile water and the bacterial suspension was streaked on yeast dextrose calcium carbonate agar medium. Ten yellow Xanthomonas-like colonies were selected after 72 hours of incubation at 28ºC in the dark. Strains were gram negative, oxidase negative and caused hypersensitive reactions on Nicotiana benthamiana (L.). All strains were genotyped after whole-cell DNA extraction by BOX-PCR (Louws et al. 1999) and had the same banding profile. Four 8-wk-old lavender plants (Lavandula dentata and Lavandula × ginginsii 'Goodwin Creek Gray') were spray-inoculated with a 106 CFU/ml suspension of strain SM175-2018 in sterile water. Control plants were sprayed with sterile water. Plants were kept in plastic bags for the first 48 h at 28°C with a 14-h photoperiod. Water-soaked necrotic lesions appeared 14 days after inoculation with SM175-2018, whereas mock-inoculated plants did not show symptoms. Bacterial isolation from symptomatic leaf tissue was carried out as described above. The BOX-PCR profile of the re-isolated strain was identical to that of SM175-2018. Multilocus sequence analysis of the housekeeping genes fuyA, gyrB, and rpoD was performed (Accession numbers: MT764834 - MT764836). The resulting concatenated data set was used to perform a phylogenetic analysis using maximum likelihood criteria to evaluate relationships with closely related Xanthomonas spp. using published reference sequences (Young et al. 2008). SM175-2018 was assigned to the X. hortorum clade (Moriniere et al. 2020) with strong bootstrap support. The strain was subjected to whole genome analysis. Genomic DNA was extracted using a QIAGEN Genomic DNA buffer set with genomic-tip 100/G following manufacturer's protocol and sequenced using the iSeq-100 Illumina platform with the Nextera DNA Flex Library Prep protocol kit and Nextera DNA CD indexes. Average nucleotide identity (ANI) analysis was performed with the ANI-Matrix software Enveomics tool (Rodriguez-R and Konstantinidis 2016) using the sequenced genome (NCBI GenBank Biosample no. SAMN11831455) and those of other X. hortorum (Vauterin et al. 1995) bacteria (pvs. hederae, carotae, vitians). SM175-2018 shared a 96% ANI with other X. hortorum strains. X. hortorum is associated with bacterial leaf spot of carrot (Scott and Dung, 2020) and also reported on ornamental plants (Mirik et al. 2010, Oliver et al. 2012, Roberts and Parkinson 2014, Klass et al. 2019), however additional research is needed to establish the host specificity of lavender strains. To our knowledge this is the first report of X. hortorum causing bacterial leaf spot of lavender in Ohio. The disease may negatively impact the yield and quality of flowers used in production of lavender oils and essences.

Enhanced bioactive compounds composition in Lavandula officinalis in-vitro plantlets using NaCl and Moringa oleifera, Aloe vera and Spirulina platensis extracts

Biotic and abiotic elicitors have been reported to promote growth or multiplication as well as alter bioactive compositions of different plant species. Lavandula officinalis is a perennial plant, which produces fragrant flowers that are utilized to prepare the lavender oil. Lavender oil is rich in beta-linalool, cineol, camphor and many other bioactive compounds, which together contributes to its pain relieving, antimicrobial and cicatrizing activities. Micropropagation is a good alternative to propagate lavender as it reduces the time required to achieve the production of essential oil and eliminates the exposures of the lavender plants to environmental pollutants, thus ensuring a better quality of the oil produced. In this study, we have investigated the effects of 3 biotic elicitors - Moringa oleifera leaf extract (MLE), Aloe vera leaf extract (ALE), Spirulina platensis aqueous extract (SAE) and an abiotic elicitor - Sodium chloride (NaCl) on the growth, multiplication and phytochemical compositions of Lavandula officinalis in-vitro plantlets. All tested biotic elicitors (MLE, ALE, SAE) negatively affected the plantlets fresh weight and shoots height. However, these elicitors were found to enhance the number of leaves per explant. On the other hand, the effect of abiotic elicitor (NaCl) were opposite to that of the biotic elicitors. In contrast to the negative growth effects, SAE and high ALE concentration (40 ml/L) were found to enhance number of shoots per explant. Interestingly, we found that all tested biotic and abiotic elicitors were able to increase the beta-linalool contents in the L. officinalis in-vitro plantlets. We observed that SAE is the best elicitor among the 4 tested elicitors because both 0.5 and 1.0 g/L SAE were able to increase linalool production and enhanced shoots proliferation.

EFFECT OF SOME AMINO ACIDS CONCENTRATION ON GROWTH AND YIELD OF LAVENDER (Lavandula officinalis, CHAIX) PLANT UNDER DIFFERENT NPK FERTILIZATION LEVELS

Two field experiments were conducted at the experimental farm, Faculty of Agriculture, Zagazig University, Egypt during the two consecutive summer seasons of 2018 and 2019. They study aimed to investigate the effect of different NPK fertilization levels (0.0, 25, 50, 75 and 100% of recommended rate), amino acid concentrations (control, L-tryptophan acid at 50 and 100 ppm as well as phenylalanine acid at 150 and 300 ppm) and their interactions on growth and yield components of lavender (Lavandula officinalis, Chaix) plant. The NPK recommended rates (RR) were 61.5, 31 and 24 kg of N, P2O5 and K2O/faddan, respectively. The obtained results pointed out that the maximum value for each of plant height, number of branches/plant, fresh and dry weights of roots/plant and root length as well as fresh and dry weights of lavender herb/ plant and /faddan were recorded when lavender plants were fertilized with 100% RR of NPK. Also, increasing NPK fertilization levels gradually increased abovementioned parameters. Foliar spray with L-tryptophan at 100 ppm, significantly increased lavender growth parameters and yield components compared to spraying with the other amino acid concentrations and control (untreated plants), in most cases. Generally, the best interaction treatment in this connection was obtained by the treatment of 100% recommended rate of NPK and spraying with 100 ppm of L-tryptophan acid.

Research Concerning the Use of Different Mulching Methods on Lavender

Lavandula angustifolia Mill. is a highly appreciated and precious shrub worldwide due to the high essential oil content and properties. The aim of this research was to determine the influence of organic farming on lavender production. The experiment was carried out during a 2-years period (2018 - 2019) at the University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, in the experimental field. The biological material used in this experiment was represented by two Lavandula angustifolia Mill. cultivars (‘Codreanca’ and ‘Sevtopolis’). The observations consisted of the evaluation of weed density, two times/year, at the beginning and at the end of the flowering period of the lavender plants. As expected, the highest weed density was in the control treatment followed by the straw/hay treatment while the lowest weed density was recorded in the treatment with the mulch foil.

Drought-Induced Mortality: Branch Diameter Variation Reveals a Point of No Recovery in Lavender Species.

In the context of climate change, determining the physiological mechanisms of drought-induced mortality in woody plants and identifying thresholds of drought survivorship will improve forecasts of forest and agroecosystem die-off. Here, we tested whether continuous measurements of branch diameter variation can be used to identify thresholds of hydraulic failure and physiological recoverability in lavender (Lavandula angustifolia and Lavandula × intermedia) plants exposed to severe drought. Two parameters of branch diameter variation were tested: the percentage loss of diameter and the percentage loss of rehydration capacity. In two greenhouse experiments with different growth conditions, we monitored variation in branch diameter in the two lavender species exposed to a series of drought/rewatering cycles that varied in drought-stress intensity. Water potential, stomatal conductance, loss of xylem hydraulic conductance, and electrolyte leakage were also measured. We observed that plants were not able to recover when percentage loss of diameter reached maximum values of 21.3% ± 0.6% during drought, regardless of species and growth conditions. A percentage loss of rehydration capacity of 100% was defined as the point of no recovery, and was observed with high levels of cellular damage as estimated by electrolyte leakage measured at 75.4% ± 9.3% and occurred beyond 88% loss of xylem hydraulic conductance. Our study demonstrates that lavender plants are not able to recover from severe drought when they have used up their elastic water storage. Additionally, drought-induced mortality in these species was not linked to xylem hydraulic failure but rather to high levels of cell damage.

Phytomanagement of a chromium-contaminated soil by a high-value plant: Phytostabilization of heavy metal contaminated site

Phytoremediation of metal-contaminated soil can be an eco-friendly technology. However, relatively long cultivation times impedes its popularization on a commercial scale. This study evaluated the effectiveness of lavender plants (Lavandula dentata L.) to remediate a highly chromium (Cr)-contaminated site through a pot experiment. The lavender growing soil was mixed both with and without biochar (2.5% w/w) + oyster shell waste (2.5% w/w) and biochar (2.5% w/w) + citrus peel waste (2.5% w/w). The results indicated that Cr(VI) accounted for 19.0% to 4.7% of the total soil Cr, while Cr(III) accounted for 81.0% to 95.3%, from the beginning to the end of the cultivation. The water-soluble Cr concentration decreased from 44.6 mg/kg to 7.5 mg/kg. The biomass of the lavender growing in the contaminated soil decreased by factors in the range between 4-fold and 6-found.The addition of soil amendments significantly reduced the (potential) bioavailable Cr (p < 0.05) in the range of 2 to 3 fold, consequently improving the growth of lavender in the highly toxic soil. In addition, the soil amendments significantly reduced the Cr bioaccumulation and the translocation from the roots to the shoots. These results showed that the cultivation of lavender with suitable amendments can effectively be used for phytomanagement techniques in highly contaminated soil.