scholarly journals Evaluation of Antifungal Activities of Five Plant Extracts against Pseudoperenospora cubensis (Downy Mildew) in Muskmelon (Cucumis melo L.)

Author(s):  
M. J. Falade ◽  
O. A. Borisade ◽  
M. Aluko

Laboratory study was conducted to evaluate the effect of leaf extracts of five indigenous plant on conidia germination, growth and sporulation of Pseudoperenospora cubensis causing downy mildew disease of muskmelon. Extracts of five plant; mexican sunflower (Tithonia diversifolia), bush banana (Uvaria chamae), salt and oil tree (Cleistopholis patens), goat weed (Ageratum conyzoides) and African eggplant (Solanum macrocarpon) at Four concentrations (15, 30, 45 and 60%) were tested against the growth, conidial germination and sporulation of Pseudoperenospora cubensis in vitro. Results show that all the plant extracts significantly inhibited conidia germination and radial growth compared to the control. The extracts had no significant (p≤0.05) effect on sporulation. The rate of inhibition of growth and conidia germination was concentration dependent being highest at 60% for the extracts. The extracts of Solanum macrocarpon was the most effective followed by Ageratum conyzoides, Cleistopholis patens and Uvaria chamea whileTithonia diversifolia caused the least inhibition of growth and conidia germination. At 15, 30, 45 and 60% concentrations growth of Pseudoperenospora cubensis on PDA modified with Solanum macrocqrponwere 3.79, 3.65, 3.33 and 2.87; and 4.25, 4.12, 3.92 and 3.89 for PDA modified with Tithonia diversifolia. Similarly, conidia germination percentages recorded at same concentration of extracts S. macrocarpon were 87, 85, 70 and 62% while that of T. diversifolia were 91, 87, 84 and 72%. The study shows that the plant extracts has the potential for inhibition of the pathogen.

1970 ◽  
Vol 1 (4) ◽  
pp. 82-88 ◽  
Author(s):  
MJ Foysal ◽  
MM Rahman ◽  
M Alam

Studies were conducted to identify Pseudomonas fluorescens isolates from a collection of bacteria isolated from bacterial haemorrhagic septicaemia infected carp and catfish, evaluate their antibiotic sensitivity pattern and screen the antibacterial activity of some medicinal plant extracts against the isolates.. A total of 10 isolates were identified as P. fluorescens by morphological, physiological and biochemical tests. In vitro antibiotic sensitivity test of the P. fluorescens isolates were conducted by disc diffusion method for seven antibiotics where, all of the isolates were found to be sensitive only against streptomycin and gentamycin but, most of the isolates (80%) were found resistant to chloramphenicol (C). Moreover, eighty percent of the isolates showed resistance to multiple antibiotics. A total of 118 plant extracts were screened for their antibacterial activity against the P. fluorescens isolates where the isolates exhibited sensitivity to 30 samples. Leaf extracts of Tamarindus indicus, Terminalia chebula, Citrus aurantifolia, Eugenia caryophyllata and Spondias pinnata were found to inhibit the growth of all of the P. fluorescens isolates. DOI: http://dx.doi.org/10.3329/ijns.v1i4.9733 IJNS 2011 1(4): 82-88


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
M. M. Rahman ◽  
A. A. Khan ◽  
M. E. Ali ◽  
I. H. Mian ◽  
A. M. Akanda ◽  
...  

Extracts from eleven different plant species such as jute (Corchorus capsularisL.), cheerota (Swertia chiraitaHam.), chatim (Alstonia scholarisL.), mander (Erythrina variegata), bael (Aegle marmelosL.), marigold (Tagetes erecta), onion (Allium cepa), garlic (Allium sativumL.), neem (Azadiracta indica), lime (Citrus aurantifolia), and turmeric (Curcuma longaL.) were tested for antibacterial activity against potato soft rot bacteria,E. carotovorasubsp.carotovora (Ecc)P-138, underin vitroand storage conditions. Previously,EccP-138 was identified as the most aggressive soft rot bacterium in Bangladeshi potatoes. Of the 11 different plant extracts, only extracts from dried jute leaves and cheerota significantly inhibited growth ofEccP-138in vitro. Finally, both plant extracts were tested to control the soft rot disease of potato tuber under storage conditions. In a 22-week storage condition, the treated potatoes were significantly more protected against the soft rot infection than those of untreated samples in terms of infection rate and weight loss. The jute leaf extracts showed more pronounced inhibitory effects onEcc-138 growth both inin vitroand storage experiments.


2010 ◽  
pp. 96-104
Author(s):  
Rokshana Panna ◽  
FM Aminuzzaman ◽  
MR Islam ◽  
MHM Borhannuddin Bhuyan

Studies were conducted in the Seed Pathology Laboratory, Department of Plant Pathology, Sher-e-Bangla Agricultural University to evaluate some indigenous plant extracts on the incidence of Bipolaris sorokiniana of wheat and seed germination. Seed treated with plant extracts reduced the incidence of Bipolaris sorokiniana. The lowest incidence was counted (12.33%) in seeds treated with Burmuda grass extracts (1:2W/V). While the highest seed germination (99.60%) was recorded in seeds treated with this grass extract followed by 99.33% germination in seeds treated with Neem leaf extract (1:2W/V), 98.00% with nut sedge grass rhizome extract (1:2 W/V), 87.67% with Allamanda leaf extract (1:2W/V). Comparatively the lowest incidence of Bipolaris sorokiniana (14.00%) was observed in seeds treated with Neem leaf extracts (1:2W/V) followed by 14.50% in seeds treated with Nut sedge grass rhizome extracts (1:2W/V), Black cumin seed extracts (15.20%) and Allamanda leaf extract (24.00%).


2018 ◽  
Vol 5 (2) ◽  
pp. 67 ◽  
Author(s):  
Rita Harni ◽  
Efi Taufik ◽  
Samsudin Samsudin

<em>Rust disease caused by fungus </em>Hemileia vastatrix<em> is a major disease of Arabica coffee</em><em>, which reduces yield by 20%–70%.</em> <em>Botanical fungicide </em><em>is a potential alternative because environmentally friendly and safe to humans health. The research aimed to analyze the effect of oils and extracts of fungicidal plants on uredospore germination and attack intensity of </em>H. vastatrix<em>. The research was conducted </em><em>in laboratory and greenhouse of Indonesian Industrial and Beverages Crops Research Institute (IIBCRI), Sukabumi, from January to December 2016. The plant oils were of cloves, citronella, </em>Reutealis trisperma<em>, and neem, while the plant extracts use</em><em>d were mahogany, </em>Ageratum conyzoides<em>,</em><em> and wood vinegar. Those oils and extracts were assessed on uredospores germination of </em>H. vastatrix<em>, both in vitro and on coffee seedling</em><em>s in the greenhouse. A complete randomized block design was used with 9 treatments and 5 replications. The oils and extracts at 5% concentration were applied on coffee leaves of 6 months old plants then inoculated with </em>H. vastratrix<em> uredospora simultaneously. </em><em>Attack symptoms, incubation period, attack percentage and intensity were observed. The results showed that plant oils and extracts used in present study effectively reduced the uredospora germination of </em>H. vastatrix<em>. </em><em>However, oils of neem and </em>R. trisperma<em> </em><em>as well as </em>A. conizoides<em> extract are more potential to suppress </em>H. vastatrix<em> infection in coffee le</em><em>aves in greenhouse and reduced attack intensity from 22.2% to 3.6%; 5.2%; and 7.6% with inhibitory level at 83.8%; 76.6%; and 65.8%, respectively. Therefore, they are considered as potential biocontrols for rust disease.</em>


2017 ◽  
Vol 43 (2) ◽  
pp. 223-232
Author(s):  
Md Adnan Al Bachchu ◽  
Kismot Ara ◽  
Md Nizam Uddin ◽  
Roushan Ara

An investigation was carried out on the larvicidal efficacy of four indigenous plant extracts against the 6th instar larvae of red flour beetle, Tribolium castaneum (Herbst) during the period of February to July 2016. The result revealed that all the four plant extracts were effective in checking insect infestation and had different toxic effects against the 6th instar larvae of red flour beetle. Average mortality indicated that castor plant extract showed the highest toxic effect (average mortality 57.78%) whereas the lowest toxicity (average mortality 27.46%) was found in the neem leaf extracts. The larval mortality significantly differed among all the concentrations of the plant extracts applied and the highest mortality (60.75%) was recorded in maximum concentration (10.61 mg/cm2) of the plant extract. No larval mortality was observed in untreated control up to 72 HATs. Mortality percentage was also observed directly proportional to the level of concentrations of plant extracts and to the exposure period. Probit analysis of larval mortality also revealed that the castor plant extract showed the highest toxicity at different time interval among all the plant extracts applied. Asiat. Soc. Bangladesh, Sci. 43(2): 223-232, December 2017


Author(s):  
Abiodun Olusoji Owoade ◽  
Adewale Adetutu ◽  
Olufemi Ogundeji Ogundipe ◽  
Akinade William Owoade

This study was carried out to compare the in-vitro antioxidant potentials, antidiabetic and phytochemical constituents of methanolic leaf extracts of Anthocleista djalonensis, Chrysophyllum albidium, Bauhinia thonningii, Daniellia oliveri, and Cola nitida. The results of this study show that all the plant extracts have strong antioxidant potentials against various radicals. The extracts scavenged DPPH and ABTS radicals, in a concentration-dependent manner and scavenged nitric oxide radicals with IC50 values of 152.39, 186.36, 213.40, 303.58 and 355.53 µg/ml for C. albidium, D. oliveri, C. nitida, A. djalonensis and B. thonningii, respectively. All the extracts also inhibited the induction of lipid peroxidation and α-amylase activity in a concentration-dependent manner, while the degree of ferric reducing power by the extracts was of the order C. albidium > D. oliveri > B. thonningii > C. nitida > A. djalonensis. Phytochemical and gas chromatography analyses carried out on the extracts revealed the presence of known chemical constituents. The amounts of total phenolics in A. djalonensis, C. albidium, B. thonningii, D. oliveri, and C. nitida were 68.39 mg/g, 95.11 mg/g, 61.03 mg/g, 103.74 mg/g, and 63.31 mg/g, respectively, in gallic acid equivalents. In all cell-free assays, C. albidium and D. oliveri, the two plants with higher amounts of phenolic compounds, were found to be more effective as antioxidants than other plant extracts with lower phenolic contents under the same experimental conditions. Therefore, the effectiveness of the antioxidant and antidiabetic activities of these plant extracts may be related to their phenolic content. The presence of phenolics and various antioxidant compounds in the plants may explain the strong pharmacological potentials of these plants.


2014 ◽  
Vol 94 (2) ◽  
pp. 417-424 ◽  
Author(s):  
Haider M. Hassan ◽  
Zi-Hua Jiang ◽  
Christina Asmussen ◽  
Emma McDonald ◽  
Wensheng Qin

Hassan, H. M., Jiang, Z.-H., Asmussen, C., McDonald, E. and Qin, W. 2014. Antibacterial activity of northern Ontario medicinal plant extracts. Can. J. Plant Sci. 94: 417–424. In the present study, the antibacterial activity (in vitro) of the leaf and/or flower crude extracts of Anaphalis margaritacea (L.) Benth & Hook.f., Grindelia squarrosa (Pursh) Dunal, Apocynum androsaemifolium L., Arctostaphylos uva-ursi (L.) Spreng, Cornus canadensis L. and Xanthium strumarium L. medicinal plants was analyzed through the hole-plate diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays against Escherichia coli, Aeromonas caviae, Paenibacillus alvei, Micrococcus luteus, Mycobacterium avium subsp. avium and Bacillus cereus bacteria. In addition, the time-kill dynamic processes of these extracts against A. caviae, B. cereus, P. alvei, and M. luteus bacteria were also tested. The leaf and flower extracts of Anap. margaritacea and G. squarrosa possess significant antibacterial activity against all the bacteria tested, with inhibition of A. caviae, P. alvei and M. luteus within 1–12 h of incubation at MBC. Particularly, at higher concentrations of the Anap. margaritacea flower crude extract (2–3×MBC), inhibition of A. caviae, B. cereus, P. alvei, and M. luteus bacteria is achieved between 0.5 and 4 h of incubation. In addition, these extracts exhibit high inhibition diameters (majority > 18 mm) and low MIC and/or MBCs (majority=1.25 mg mL−1). In contrast, the leaf extracts of Arct. uva-ursi, X. strumarium, Apoc. androsaemifolium and C. canadensis plants demonstrate moderate to low activity. These results indicate that extracts from Anap. margaritacea and G. squarrosa could be a source of novel antimicrobial scaffolds, compounds or pharmacophores with implications in the pharmaceutical industry and medicine.


2015 ◽  
Vol 10 (2) ◽  
pp. 423
Author(s):  
Arushdeep Sidana ◽  
Umar Farooq

<p>The present study was aimed at <em>in vitro</em> antileishmanial screening of ten plants used in the traditional medicine in India. MTT method was used to evaluate the cell death after application of 100, 250, 350 and 500 μg/mL of the methanolic extracts followed by incubation for 24 hours at 25°C. Methanolic leaf extracts of <em>Acorus calamus, Alstonia scholaris</em> and <em>Berberis aristata</em> showed significant antileishmanial activity at a concentration of 500 µg/ml. In order to identify the antileishmanial compounds present in the active extracts of the screened plants, an LC-MS analysis of the tested extracts was carried out. The active extracts revealed the presence of some natural products with known antileishmanial activity along with other compounds. The present study suggests that the active plant extracts may be processed to isolate the compounds that may further be screened for their antileishmanial potential.</p>


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