Essential Oils as Biocontrol Agents of Early and Late Blight Diseases of Tomato under Greenhouse Conditions

Tomato production worldwide is usually restrained by various infections, among them mainly the late and early blight caused by Phytophthora infestans and Alternaria solani, respectively. Lately, there has been a growing concern over the use of synthetic fungicides on environmental and food safety, hence the need to explore other alternatives that are friendly to the user, the consumer, and the general environment. This research sought to test the potency of ginger, garlic, and Mexican marigold essential oils against the early and late blight diseases of tomato under greenhouse conditions. A synthetic fungicide (Ridomil Gold®) was used as a positive control while distilled water acted as a negative control. The extraction of essential oils was done by dry steam distillation and then mixed with tween twenty before being topped up with sterile distilled water. They were then used to spray tomato plants that had been inoculated with A. solani and P. infestans isolates under greenhouse conditions. The tomato plants were evaluated for growth, yield, and disease severity. The data obtained was subjected to ANOVA and separation of means was conducted using Student–Newman–Keul (SNK) test at 95% level of confidence. The three essential oils had a significant potency against the two diseases which is comparable to the synthetic fungicide. Marigold essential oil was also found to have a significant impact on the general growth of sprayed tomato plants. Essential oils of the three plants can be further explored as alternative products management of the two diseases.

Download Full-text

In Vitro Control of Phytophthora infestans and Alternaria solani Using Crude Extracts and Essential Oils from Selected Plants

International Journal of Agronomy ◽

10.1155/2020/8845692 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Lydia G. Mugao ◽

Phyllis W. Muturi ◽

Bernard M. Gichimu ◽

Ezekiel K. Njoroge

Keyword(s):

Essential Oils ◽

Phytophthora Infestans ◽

Radial Growth ◽

Fungal Growth ◽

Alternaria Solani ◽

Growth Media ◽

Distilled Water ◽

Tomato Production ◽

Crude Extracts

Tomato production is constrained by fungal diseases especially the early and late blight caused by Alternaria solani and Phytophthora infestans, respectively. Control of the two diseases is usually by use of synthetic fungicides which have a long residue effect and also contribute to environmental pollution. Innovative use of biocontrols may offer an eco-friendly and more sustainable solution. This study tested the in vitro efficacy of crude extracts and essential oils of ginger, garlic, tick berry, and Mexican marigold in inhibition of radial growth of A. solani and P. infestans. Extraction of the crude extracts was done using distilled water, ethanol, and methanol solvents, while essential oils were extracted using the dry steam distillation method. The extracts and essential oils were used to amend the growth media of the test pathogens before introducing the precultured pathogens. Sterile distilled water and synthetic fungicide, Ridomil Gold®, were used as positive and negative controls, respectively. Fungal growth inhibition was determined by measuring the radial growth of the test pathogens. Both the crude extracts and the essential oils portrayed some efficacy against the test pathogens. Garlic crude extracts were found to be the most effective, while ethanol was the most suitable extraction solvent. Essential oils were more effective in restricting the pathogen growth than crude extracts. Ginger and garlic oil was found to be as effective as the synthetic fungicide, and thus it was concluded that the two plants have strong antifungal properties with high potential of being utilized as biofungicides. However, effective utilization of these products in farmers’ fields may require industrial formulation to improve their efficiency.

Download Full-text

Essential oils as tick repellents on clothing

Experimental and Applied Acarology ◽

10.1007/s10493-019-00422-z ◽

2019 ◽

Vol 79 (2) ◽

pp. 209-219 ◽

Cited By ~ 3

Author(s):

Oliver Soutar ◽

Freya Cohen ◽

Richard Wall

Keyword(s):

Essential Oils ◽

No Reduction ◽

Positive Control ◽

Negative Control ◽

Tick Abundance ◽

Spearmint Oil ◽

Oregano Oil ◽

Negative Controls ◽

Tick Repellents

Abstract Essential oils show promise as natural alternatives to synthetic tick repellents, but few studies have investigated their repellent efficacy in vivo or under field conditions. Here, blanket-drags and standardised walks were employed to evaluate tick acquisition by 1 m2 cotton blankets or cotton trousers, respectively, in woodland edge habitats of known high tick abundance. Blankets and trousers had been treated with one of 5% oregano, rosemary, spearmint or thyme oils, 20% DEET (N,N-diethyl-3-methylbenzamide) (positive control) or ethanol excipient-only (negative control). The number of ticks present on the blankets or trousers differed significantly between treatments: spearmint oil treatments resulted in significantly fewer ticks than the negative controls for both blankets and trousers and significantly fewer ticks were present on the oregano oil treated blankets. For ticks that did attach to the trousers, the rate of drop off within 3 min was significantly higher for trousers treated with spearmint oil or thyme oil than ethanol, oregano oil and rosemary oil. No reduction in repellence was detected over a 24 h period between treatment and testing. The results suggest that 5% oregano and spearmint oils exhibit potential as natural clothing repellents, with an effective equivalence to 20% DEET.

Download Full-text

Effects of avilamycin and essential oils on mRNA expression of apoptotic and inflammatory markers and gut morphology of piglets

Czech Journal of Animal Science ◽

10.17221/338-cjas ◽

2008 ◽

Vol 53 (No. 9) ◽

pp. 377-387 ◽

Cited By ~ 24

Author(s):

A. Kroismayr ◽

J. Sehm ◽

M.W. Pfaffl ◽

K. Schedle ◽

C. Plitzner ◽

...

Keyword(s):

Essential Oils ◽

Negative Control Group ◽

Positive Control ◽

Negative Control ◽

Feed Additives ◽

Feed Additive ◽

Pcr Analysis ◽

Control Group ◽

Mesenteric Lymph Nodes ◽

Tissue Samples

In this study 120 piglets were allotted to 3 dietary treatments, negative control group, one group receiving a blend of essential oils (EO) derived from oregano, anise and citrus peels (40 mg/kg diet), and a positive control group treated with avilamycin as growth promoting feed additive (40 mg/kg diet). On day 22 of the experiment, 12 representative animals from each treatment group were sacrificed and tissue samples were collected for quantitative real time-PCR analysis and gut tissue morphology. EO and avilamycin decreased the gene expression of the transcriptional factor NFκB and the apoptotic marker TNFα significantly in the ileum and jejunum, respectively. The expression of the proliferation marker Cyclin D1 was also significantly decreased by both substances in the colon, mesenteric lymph nodes and spleen. The colonic crypt depth was reduced by avilamycin, and also numerically by the essential oils. These changes correlated with the up-regulation of the apoptosis factor Caspase 3. Histomorphometry revealed a smaller size of ileal Peyer’s patches through the use of both feed additives, which correlated significantly with lower expression rates of NFκB. In conclusion, the results suggest that EO and avilamycin relieved weaning piglets from an immune defence stress in a similar way.

Download Full-text

Silver Nanoparticle of Acalypha indica Linn. Leaf As Bio-larvicide against Anopheles sp. Larvae

Open Access Macedonian Journal of Medical Sciences ◽

10.3889/oamjms.2021.6628 ◽

2021 ◽

Vol 9 (A) ◽

pp. 760-765

Author(s):

Yos Banne ◽

Olfie Sahelangi ◽

Steven Soenjono ◽

Elisabeth Natalia Barung ◽

Selfie Ulaen ◽

...

Keyword(s):

Silver Nanoparticles ◽

Silver Nanoparticle ◽

Negative Control Group ◽

Positive Control ◽

Negative Control ◽

Probit Analysis ◽

Control Group ◽

Distilled Water ◽

Lc50 Value ◽

Acalypha Indica

BACKGROUND: Acalypha indica Linn. has been used as traditional medicine, it contains flavonoids, alkaloids, tannins, saponins, steroids, triterpenoids, and essential oils. AIM: This study aimed to determine the bio-larvicide effects of A. indica Linn. leaf stew and the silver nanoparticles against Anopheles sp. larvae. METHODS: The fresh leaves of A. indica Linn. extracted using distilled water at 100°C for 30 min. The silver nanoparticles were made by mixing a solution of silver nitrate with the stew, which acts as a reducing agent. The resulting silver nanoparticles were characterized by particle size analyzer and UV-vis spectrophotometer. The bio-larvicide effects against Anopheles sp. larvae performed using a completely randomized design. There were eight groups consisted of ten larvae and three replications. Treatment groups of stew and silver nanoparticle for concentrations 0.05%, 0.5%, and 5%, respectively. The negative control group was distilled water and the positive control group was the 0.01% abate solution. Assessment of larvicide activity was carried out every hour for 6 h and continued if there were larvae that live up to 24 h. The LC50 value was calculated based on Probit analysis. RESULTS: The results showed that the A. indica Linn. leaf stew can be made into silver nanoparticles preparations, optimal results were obtained from a mixture of 1% stew and 3 mM AgNO3. The result of bio-larvicides effect test against Anopheles sp. larvae showed that the LC50 value of the A. indica Linn. leaf stew was 727,3 ppm and the LC50 value of silver nanoparticles was 3.366 ppm. CONCLUSION: It can be concluded that A. indica Linn. is a promising larvicidal plant and can be made into silver nanoparticle preparations.

Download Full-text

Pengaruh Antibakteri Ekstrak Kulit Batang Matoa (Pometia pinnata) terhadap Bakteri Staphylococcus aureus secara In vitro

Jurnal MIPA ◽

10.35799/jm.2.2.2013.3121 ◽

2013 ◽

Vol 2 (2) ◽

pp. 128 ◽

Cited By ~ 2

Author(s):

Mercy Ngajow ◽

Jemmy Abidjulu ◽

Vanda S. Kamu

Keyword(s):

Staphylococcus Aureus ◽

Secondary Metabolites ◽

Antibacterial Effect ◽

Inhibition Zone ◽

Stem Bark ◽

Positive Control ◽

Negative Control ◽

Bark Extract ◽

Distilled Water

Telah dilakukan penelitian secara kualitatif terhadap pengaruh antibakteri dari ekstrak kulit batang matoa (Pometia pinnata. Spp.) terhadap bakteri Gram positif Staphylococcus aureus . Sebelum dilakukan uji antibakteri, sampel yang telah diekstrak secara maserasi diuji fitokimia terlebih dahulu untuk menentukan kandungan metabolit sekunder yang telah diketahui berperan sebagai agen antibakteri. Setelah dilakukan uji fitokimia, ekstrak diuji aktivitas antibakterinya terhadap bakteri Staphylococcus aureus dengan menggunakan teknik difusi agar dengan cara sumuran. Ekstrak dilarutkan pada aquades steril dengan perbandingan 2 g ekstrak pada 2 mL air. Untuk kontrol positif, digunakan ciprofloxacin dan aquades steril sebagai kontrol negatif. Hasil penelitian ini menunjukkan bahwa ekstrak kulit batang matoa memiliki aktivitas antibakteri setelah diinkubasi selama 24 jam pada 37 OC. Dari 3 kali pengulangan dengan masing – masing 3 sumuran, didapat zona hambat masing – masing 16.84 mm, 12.5 mm dan 14.5 mm dengan kontrol positif 29.67 mm serta kontrol negatif 0 mm. Hasil yang diperoleh didukung oleh keberadaan metabolit sekunder hasil uji fitokimia yaitu tanin, flavonoid, terpenoid dan saponin.A qualitative study has done of the antibacterial effect of matoa (Pometia pinnata) stem bark extract against Gram-positive bacteria Staphylococcus aureus . Before the antibacterial test , samples were extracted by maceration and then phytochemical tested to measuring the content of secondary metabolites that have been known to act as an antibacterial agent . After being tested of phytochemical , extracts were tested the antibacterial effect against Staphylococcus aureus using agar diffusion technique. Extract was dissolved in sterile distilled water with a ratio of 2 g of extract in 2 mL of water . For the positive control , use of ciprofloxacin and sterile distilled water as a negative control . Results of this study indicate that matoa bark extract has antibacterial effect after incubation for 24 h at 37OC . Of 3 times with each repetition - each 3 wells, the inhibition zone obtained - each 16.84 mm , 12.5 mm and 14.5 mm with 29.67 mm of positive control and a negative control by 0 mm . The results are supported by the presence of secondary metabolites by phytochemical test such as tannins , flavonoids , terpenoids and saponins.

Download Full-text

Effects of coronal leakage on concentration of hydrogen ions and calcium release of several calcium hydroxide pastes over different periods of time

Journal of Research in Dentistry ◽

10.19177/jrd.v1e32013230-239 ◽

2013 ◽

Vol 1 (3) ◽

pp. 230

Author(s):

Mariana Pires Crespo ◽

Milton Carlos Kuga ◽

Marcus Vinicius Reis Só ◽

Katia Cristina Keine ◽

André Luis Shinohara

Keyword(s):

Calcium Hydroxide ◽

Calcium Release ◽

Water Concentration ◽

Positive Control ◽

Negative Control ◽

Distilled Water ◽

Filling Material ◽

Hydrogen Ions ◽

Ion Release ◽

Temporary Filling

PURPOSE: To evaluate the effects of coronal leakage on concentration of hydrogen ions (pH) and calcium release of several calcium hydroxide pastes, over different periods of time. MATERIAL AND METHODS: Fifty extracted human mandibular central incisors (n=10) were instrumented up to the F2 instrument and assigned to the following intracanal dressing: G1- Calen, G2- Calen with 0.4% chlorhexidine (CHX), G3- Calcium hydroxide with camphorated paramonochlorophenol (CPMC) and glycerin, G4- Calen, but temporary filling material maintained during all test (positive control) and G5- Root canal without intracanal dressing (negative control). All groups were immersed in distilled water for 7 days. In sequence, the temporary filling materials were removed, except in controls groups. All specimens were individually mounted on a specific device and only its root again immersed in distilled water. Concentration of hydrogen ions and calcium release by calcium hydroxide pastes in distilled water were evaluated in 24h, 7, 14 and 28 days. The results were submitted to ANOVA test (p = 0.05). After 28 days, root canals from experimental groups were examined in SEM. RESULTS: G1, G2, G3 and G4 presented similar pH values and calcium release and did not differ from each other (p>0.05), up to 7 days. After this time G1, G2 and G3 presented values lower values than G4 (p<0.05). In SEM analysis, calcium hydroxide residues were observed in all experimental groups. CONCLUSIONS: After 7 days, coronal leakage decreased the concentration of hydrogen ions and calcium ion release provided by all calcium hydroxide pastes.

Download Full-text

UJI EFEK ANTIPIRETIK EKSTRAK MENIRAN (Phyllantus niruri L.) PADA TIKUS WISTAR (Rattus norvegicus) JANTAN YANG DIINDUKSI VAKSIN DPT-HB

Jurnal e-Biomedik ◽

10.35790/ebm.3.1.2015.7427 ◽

2015 ◽

Vol 3 (1) ◽

Author(s):

Ivana Jansen ◽

Jane Wuisan ◽

Henoch Awaloei

Keyword(s):

Wistar Rats ◽

Negative Control Group ◽

Positive Control ◽

Negative Control ◽

Control Group ◽

Distilled Water ◽

Phyllanthus Niruri ◽

Antipyretic Effect ◽

Flower Extract ◽

Hb Vaccine

Abstract: The aim of this study is to investigate the antipyretic effect of leaf-flower extract (Phyllanthus niruri L.) in Wistar rats induced by DPT-HB vaccine. Samples were 15 Wistar rats as test animals and were divided into five groups of three in each. The negative control group was given orally distilled water, positive control group was given paracetamol and 3 experimental groups were given ethanolic leaf-flower extracts (100 mg, 200 mg and 300 mg /200 g body weight of rats). Pyrexia was induced in rats by intramuscular injection of 0.2 ml DPT-HB vaccine. Antipyretic activity was measured at 0, 30, 60, 90, 120, 150, 180 minutes after administration of leaf-flower extract, paracetamol and distilled water. The results showed that leaf-flower extract at a dose of 300 mg /200 g BW decreased the rectal temperature greater than with doses of 100 and 200 mg /200 g BW for 180 minutes of measurement. Conclusion: Leaf-flower extract has antipyretic effect in Wistar rats.Keywords: antipyretic, phyllanthus niruri, DPT-HB, wistar ratAbstrak: Penelitian ini bertujuan untuk menguji efek antipiretik ekstrak meniran (Phyllanthus niruri L.) pada tikus Wistar yang diinduksi vaksin DPT-HB. Metode: Hewan uji yang digunakan adalah 15 ekor tikus Wistar yang dibagi ke dalam 5 kelompok, masing-masing kelompok terdiri dari 3 ekor tikus. Kelompok kontrol negatif diberikan aquades, kelompok kontrol positif diberikan parasetamol, dan 3 kelompok eksperimental diberikan ekstrak tanaman meniran masing-masing dengan dosis 100mg, 200mg dan 300 mg/200 grBB tikus. Induksi demam pada hewan uji menggunakan vaksin DPT-HB 0,2ml secara intramuskular. Pengukuran suhu rektal dilakukan sebelum dan sesudah pemberian vaksin dan setelah pemberian bahan uji yaitu pada menit ke-30, 60, 90, 120, 150 dan 180. Hasil penelitian memperlihatkan pemberian ekstrak meniran dengan dosis 300 mg/200 grBB menunjukkan penurunan suhu rektal lebih besar dibanding dengan dosis 100 dan 200 mg/200 grBB selama 180 menit pengukuran. Simpulan: Ekstrak meniran memiliki efek antipiretik pada tikus Wistar.Kata kunci: antipiretik, phyllanthus niruri, DPT-HB, tikus wistar

Download Full-text

An In Situ Study of the Influence of Staining Beverages on Color Alteration of Bleached Teeth

Operative Dentistry ◽

10.2341/15-306-l ◽

2016 ◽

Vol 41 (6) ◽

pp. 627-633 ◽

Cited By ~ 5

Author(s):

AL Briso ◽

TC Fagundes ◽

MO Gallinari ◽

J Moreira ◽

LCAG de Almeida ◽

...

Keyword(s):

Color Change ◽

Grape Juice ◽

Study Groups ◽

Positive Control ◽

Negative Control ◽

Distilled Water ◽

Dental Bleaching ◽

Tooth Color ◽

Mean Values ◽

Bleaching Treatment

SUMMARY The aim of this study was to evaluate overall color change in bovine tooth fragments submitted to dental bleaching treatment performed simultaneously with the ingestion of beverages containing dyes. For this purpose, tooth fragments assembled into intraoral devices were submitted to at-home dental bleaching using 10% carbamide peroxide (CP) for 14 days and to immersion in staining beverages for 10 minutes daily. The specimens were divided into the following study groups according to bleaching treatment and staining substance (n=12): G I (negative control): no bleaching + distilled water; G II (positive control): bleaching + distilled water; G III: bleaching + coffee; and G IV: bleaching + grape juice. Twelve volunteers used the device continually, except during meals, oral hygiene, dental bleaching, and pigment challenge. Color readings were performed using a spectrophotometer both before the bleaching treatment and after each treatment week. The results were submitted to the normality test. The data obtained were submitted to analysis of variance and the Tukey or Kruskal-Wallis and Dunn tests (α=0.05). All bleached groups showed similar ΔE results at the end of treatment. Staining beverages generated negative ΔL mean values, and the lowest result was obtained in the treatment with coffee after 14 days. The Δa values in the groups that received treatment with staining beverages were higher when compared to the control groups. Dental bleaching associated with the consumption of staining substances may not affect overall tooth color change by the end of the treatment, although the consumption of staining substances did influence the different color dimensions.

Download Full-text