scholarly journals Efficacy of Two New Fungicides Against Colletotrichum Kahawae Infecting Coffee in Kenya

2021 ◽  
Vol 9 (2) ◽  
pp. 83-90
Author(s):  
Samuel Musime Malaka ◽  
Getrude Okutoyi Alwora ◽  
Shem Nchore Bonuke
Keyword(s):  
Negative Control ◽  
Potato Dextrose Agar ◽  
Control Treatment ◽  
Coffee Berry ◽  
Control Data ◽  
Colony Diameter ◽  
Colletotrichum Kahawae ◽  
Poisoned Food Technique ◽  
Positive Controls

Coffee Berry Disease(CBD) caused by Colletotrichum kahawae is a destructive fungal disease of coffee in Kenya, leading to a loss of about 75%. This study aimed to assess the In Vitro efficacy of two fungicides:- CRI 1 (Pyraclostrobin 150 g/L + Fluxapyroxad 75 g/L) and CRI 2 (Pyraclostrobin 128 g/Kg + Boscalid 252 g/Kg) against C. kahawae using poisoned food technique on Potato Dextrose Agar. A total of 170 coffee berries with C. kahawae symptoms were purposively collected from both sprayed and unsprayed plots. Ten rates of each of the two fungicides were assessed ranging from 0.01% to 0.1% at an interval of 0.01%. Two commercial standard fungicides Pyraclostrobin 250 g/L at 0.04% and Tebuconazole 200 g/L + Trifloxystrobin 100 g/L at 0.1% were used as positive controls. Fungal inoculum in PDA media devoid of the fungicide acted as the negative control. Data on colony diameter was collected after every 24 hours for 13 days. Analysis of Variance (ANOVA) of the data on colony diameter was done using CoStat software version 6.400. The results revealed that all the rates of CRI 1 and CRI 2 fungicides controlled the colony diameter of C. kahawae compared to the control treatment. CRI 1 fungicide suppressed the growth of C. kahawae even at the lowest concentration of 0.01% with a percentage control of 64.74 %. The highest concentration of 0.1% had a percentage control of 66.15% . CRI 1 is more effective in controlling C. kahawae since it controls the fungus at a rate even lower than Pyraclostrobin 250 g/L which had a percentage control of 66.10 at a recommended rate of 0.04% and Tebuconazole 200 g/L + Trifloxystrobin 100 g/L fungicides which had a percentage control of 65.76 at a recommended rate of 0.1%. CRI 1 also hade a better percentage control as compared to CRI 2. CRI 2 had a percentage control of 54.63% at the highest rate of 0.1% and a percentage control of 35.60% at the lowest rate of 0.01% . Further studies on CRI 1 and CRI 2 fungicides should be carried out for yield assessment in the field.

scholarly journals The Potential of Fungi as Bio-Control Agents in Managing Colletotrichum Kahawae In Kenya

2021 ◽  
Vol 9 (3) ◽  
pp. 171-178
Author(s):  
Happiness Nyambuge Msenya ◽  
Steven Runo ◽  
Douglas Watuku Miano ◽  
Mary Wanjiku Gikungu ◽  
Elijah Kathurima Gichuru ◽  
...  
Keyword(s):  
Potato Dextrose Agar ◽  
Coffee Berry ◽  
Coffee Production ◽  
Coffee Berry Disease ◽  
Colletotrichum Kahawae ◽  
Environment And Health ◽  
Inhibition Of Growth ◽  
Resistant Varieties ◽  
Antagonistic Potential

Colletotrichum kahawae is a causative fungal agent of Coffee Berry Disease (CBD) that negatively affects coffee production. Its control relies on use of resistant varieties and chemical control. Fungicides used in control of CBD are costly and pose a risk to environment and health. The study was aimed at assessing the possible antagonistic potential of fungal isolates against Colletotrichum kahawae in in vitro conditions. Five isolates were used; one isolate was collected from berries while the rest were collected from soil. Testing for antagonism against Colletorichum kahawae was done by co-culturing the isolates on Potato Dextrose Agar. The degree of antagonism was determined by measuring and comparing the radial growth of pathogen with the bio-agent against the control. Out of the five isolates tested against C. kahawae, three isolates Fusarium proliferetum, Penicillium and Fusarium ceraneasum significantly inhibited test pathogen growth at 60%, 55% and 45.45%, respectively. The other isolates, Fumigatus aspergillus and Chaetomium perithecia showed inhibition of growth at 40% and 18.18% respectively. It was concluded that there is potential of using fungi as bio control of the coffee berry disease.

Evaluation of Commercial Latex as a Positive Control for In Vitro Testing of Bioceramics

2014 ◽  
Vol 631 ◽  
pp. 357-362 ◽  
Author(s):  
Emanuelle Stellet Lourenço ◽  
Juliana Côrtes ◽  
Joyce Costa ◽  
Adriana Linhares ◽  
Gutemberg Alves
Keyword(s):  
Cell Viability ◽  
Cell Survival ◽  
Low Cost ◽  
Control Cell ◽  
Experimental System ◽  
Biological Evaluation ◽  
Negative Control ◽  
International Standards ◽  
Positive Controls

Several tests for the biological evaluation of bioceramic materials and medical devices are provided in specific international standards, where in vitro tests have a major role. Tests involving exposure of cells in culture require the use of validated positive controls, which, in the same preparation and treatment conditions, present a substantial and well-known cytotoxicity. The present work aimed to test and validate 3 different sources of low cost, commercially available latex, as positive controls in cytotoxicity tests for bioceramic materials performed by indirect exposure. The tested origins for latex samples were: surgical gloves without powder, 100% pure amber latex hospital-grade tourniquets and 60 % latex White tubing. MC3T3-E1 murine pre-osteoblasts in culture were exposed to conditioned media (extracts) of each material tested, along with sintered stoichiometric hydroxyapatite bioceramics, and polystyrene beads as negative control. Cell viability was determined by XTT and Crystal Violet Exclusion tests. Concentration curves of the extracts were performed to obtain the DC50. Only the 100% pure amber latex tubing was proven to be cytotoxic, with cell survival less than 5%. This material did not affected neighboring groups at the same experimental system. Moreover, latex samples showed great repeatability in different tests against latex and biomaterials, with consistent toxicity under 20% cell survival as shown in 3 different cell viability parameters. We conclude that fragments of latex ambar tubing are suited as effective positive controls in tests of medical bioceramic materials.

scholarly journals Meloidogyne javanica control by Pochonia chlamydosporia, Gracilibacillus dipsosauri and soil conditioner in tomato

2013 ◽  
Vol 39 (2) ◽  
pp. 122-125 ◽  
Author(s):  
Guilherme Silva de Podestá ◽  
Leandro Grassi de Freitas ◽  
Rosangela Dallemole-Giaretta ◽  
Ronaldo João Falcão Zooca ◽  
Larissa de Brito Caixeta ◽  
...  
Keyword(s):  
Meloidogyne Javanica ◽  
Positive Control ◽  
Nematophagous Fungus ◽  
Antagonistic Activity ◽  
Negative Control ◽  
Control Treatment ◽  
In Vitro Tests ◽  
Pochonia Chlamydosporia ◽  
Soil Conditioner

Organic matter plays a fundamental role in the antagonistic activity of microorganisms against phytonematode populations on the soil. In this study, the compatibility between the fungus Pochonia chlamydosporia (Pc-12) and the rhizobacterium Gracilibacillus dipsosauri (MIC 14) was evaluated in vitro, as well as the effect of the fungus at the concentration of 5,000 chlamydospores per gram of soil, rhizobacterium at 4.65 x 10(9) cells/g of soil, and the soil conditioner Ribumin® at 10 g/pot, either alone or in combination, against Meloidogyne javanica population in tomato plants (3,000 eggs/pot). A suspension of water or Ribumin® alone was applied on the soil as negative control, while a suspension of nematode eggs was applied as positive control. The reduction in the number of galls in roots per plant was 48 and 41% for the treatments Ribumin + MIC 14 + Pc-12 and MIC 14 + Pc-12, respectively. Regarding to the number of eggs per plant, MIC 14 and Pc-12 + Ribumin led to a reduction by 26 and 21%, respectively, compared to the control treatment. Interaction between the nematophagous fungus and the rhizobacterium was positive for the nematode control, even though G. dipsosauri inhibited P. chlamydosporia growth by up to 30% in in vitro tests.

scholarly journals UJI EFEKTIVITAS MUKOLITIK EKSTRAK UMBI BAWANG DAYAK (Eleuherine bulbosa (Mill) Urb) SECARA IN VITRO PADA USUS SAPI

2021 ◽  
Vol 3 (2) ◽  
pp. 71-77
Author(s):  
Zulmai Rani ◽  
Robiatun Rambe
Keyword(s):  
Positive Control ◽  
Negative Control ◽  
Test Solution ◽  
Equivalent Effect ◽  
Significant Difference ◽  
The One ◽  
Tuber Extract ◽  
Better Than ◽  
Positive Controls

Dayak Onions are a typical Borneo plant that have been used by generations of Dayaks as herbal medicine. Empirically, tubers can be used as cough medicines. The purpose of this study was to determine the mucolytic effect of Dayak onion tuber extract by in vitro and the concentration range which gaves an equivalent effect with the effect of 0.1% acetylcysteine. This study conducted extraction using maceration and mucolytic effectiveness by in vitro to reduce the viscosity of cattle mucus. The test solution was made with a concentration of 0.5%, 1%, and 1.5% mixed with a mucus-phosphate buffer pH 7 20:80. The test solution was incubated for 30 minutes at 37oC. Further, positive control used was 0.1% acetylcysteine drug and the negative control was mucus solution without extract. Viscosity values obtained were analyzed using the One-way Anova statistical test with a confidence level of 99% (α 0.01). Based on the results, it was revealed that the extract of Dayak tuber with a concentration of 0.5%, 1%, and 1.5% showed a significant difference and a concentration of 0.5%.  Mucolytic effectiveness was better than positive controls (acetylcysteine).

scholarly journals Supplementation of an Orange Juice with Dietary Proteins to Prevent Enamel and Dentin Erosion

2015 ◽  
Vol 26 (3) ◽  
pp. 263-267
Author(s):  
Stella S. Ferreira ◽  
Tais Scaramucci ◽  
Anderson T. Hara ◽  
Idalina V. Aoki ◽  
Maria Angela Pita Sobral
Keyword(s):  
Orange Juice ◽  
In Vitro Study ◽  
Negative Control ◽  
Protein Supplementation ◽  
Dietary Proteins ◽  
Surface Microhardness ◽  
Human Enamel ◽  
Dentin Erosion ◽  
Positive Controls

Protein supplementation may be an alternative to reduce the erosive potential of acidic drinks. The aim of this in vitro study was to evaluate the erosive potential of an orange juice modified by dietary proteins. A commercially available orange juice was added 0.2 g/L casein, 2.0 g/L ovalbumin and their combination. The juice with no additives and a commercially available calcium-modified juice were used as negative and positive controls, respectively. Human enamel and dentin specimens (n=11) were tested in an erosion-remineralization cycling model. Enamel was analyzed by surface microhardness and profilometry, whilst dentin by profilometry only. Statistical analyses were performed using one-way ANOVA followed by Tukey's test (p<0.05). Calcium-modified juice showed the lowest erosive potential for both analyses (p<0.05). For enamel, the protein-added groups did not differ from each other (p>0.05) and showed significantly lower enamel loss compared to negative control (p<0.05). Regarding surface microhardness, casein showed the highest values compared to negative control (p<0.05). For dentin, none of the protein-added groups showed lower values of surface loss compared to negative control (p>0.05). In conclusion, for enamel the protein-modified orange juices presented reduced erosion of enamel, with casein showing a trend for better protection. For dentin, no reduction in the erosive potential was observed for the tested protein-modified orange juices.

scholarly journals Efficacy and Safety Assessment of T. Angelica Herbal Tonic, a Phytomedicinal Product Popularly Used in Nigeria

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Charles O. Esimone ◽  
Peter A. Akah ◽  
Chukwuemeka S. Nworu
Keyword(s):  
Guinea Pig ◽  
Reproductive Toxicity ◽  
Herbal Product ◽  
Negative Control ◽  
Control Treatment ◽  
Efficacy And Safety ◽  
Guinea Pig Ileum ◽  
Promoting Effect ◽  
Pregnant Rats

T. Angelica Herbal Tonic (TAHT) is a herbal product indicated for indigestion and constipation and highly patronized in Nigeria. In this study, the efficacy and safety of the herbal tonic in relation to the label claims were assessed. The effect on peristalsis in mice was evaluated by the charcoal meal model andin vitrousing guinea pig ileum. The effects of TAHT on behavior, fertility, birth and organ weights were also determined. Teratogenic potential and reproductive toxicity were studied in pregnant rats. Acute toxicity studies showed that at doses above 5000 mg kg−1, the herbal tonic did not cause lethality and produced no signs of intoxication in mice. The study did not show any gross behavioral changes in mice treated with 1000 mg kg−1of TAHT as compared with the negative control treatment. TAHT (400 mg kg−1) exhibited a dose-dependent enhancement in the gastrointestinal tract motility in mice when compared with the negative control. At concentrations up to 300 μg mL−1, TAHT did not cause any significant effect on acetylcholine, histamine and nicotine-evoked contractions of guinea pig ileum preparation. It took an average of 31.25 ± 4.52 days for the TAHT-treated animals to litter, which is significantly (P< .05) different from the 55 ± 4.51 days recorded for the control treatment group. TAHT exhibited a modest fertility-promoting effect and showed lack of abortifacient and teratogenic properties in the study. Generally, the results of this study showed some favorable pharmacological effects of TAHT in animals which may authenticate some of the label claims.

In vitro screening of coffee genotypes for resistance to coffee berry disease (Colletotrichum kahawae)

1995 ◽  
Vol 127 (2) ◽  
pp. 251-261 ◽  
Author(s):  
N. E. NYANGE ◽  
B. WILLIAMSON ◽  
R. J. McNICOL ◽  
CHRISTINE A. HACKER
Keyword(s):  
In Vitro Screening ◽  
Coffee Berry ◽  
Coffee Berry Disease ◽  
Colletotrichum Kahawae

scholarly journals Aktivitas Anti Cendawan Ekstrak Daun Sereh Wangi (Cymbopogon nardus L.) Terhadap Colletotrichum sp Penyebab Penyakit Antraknosa Pada Buah Cabai (Capsicum annum L.) Secara In Vitro Dan In Vivo

Agrologia ◽  
2015 ◽  
Vol 4 (1) ◽  
Author(s):  
Mohamad Ana Syabana ◽  
Andree Saylendra ◽  
Deri Ramdhani
Keyword(s):  
Weight Loss ◽  
Antifungal Activity ◽  
In Vitro Study ◽  
Positive Control ◽  
Negative Control ◽  
Control Treatment ◽  
Capsicum Annum ◽  
Anti Fungal

The aim of this research was to examine in vitro and in vivo anti fungal activity of citronella leaves extract against Colletotrichum sp caused antrachnose disease on chilli. The in vitro and in vivo research used randomized completely design (RCD) with one factor and five level. The factor was citronella leaves extract and the level were 0,1 % (v/v), 0,2 % (v/v), 0,3 % (v/v), 0,4 % (v/v), 0,5 % (v/v). Negative control treatment was conducted by growing Colletotrichum sp on PDA (in vitro) and chili (in vivo) without citronella leaves extract while positive control was conducted by growing Colletotrichum sp on PDA (in vitro) and chili (in vivo) containing synthetic fungicide. The in vitro study showed that the higher concentration of citronella leaves extract caused higher growth inhibition of Colletotrichum sp. Whereas the in vivo study resulted that higher concentration of citronella leaves extract caused lower incubation period of Colletotrichum sp, intensity of disease and weight loss of chillies. The highest concentration of citronella leaves extract (0,5%) has higher antifungal activity compared to other treatments and negative control while lower than positive control.

scholarly journals The Effectiveness of Kenikir and Betel Leaves Extract as Bio Fungicide to the Causes of Anthracnose Disease (Colletotrichum Capsici) on Chili Plants (Capsicum annum L.) with Invitro

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Maimunah Maimunah ◽  
Azwana Azwana ◽  
Cornelis Pandala
Keyword(s):  
Capsicum Annuum ◽  
Positive Control ◽  
Negative Control ◽  
Research Use ◽  
Anthracnose Disease ◽  
Betel Leaf ◽  
Colony Diameter ◽  
Capsicum Annum ◽  
Colletotrichum Capsici

Effectiveness Kenikir and Betle Leaft Extraction as Biofungicide to Cause Disease Antraknosa (Colletotricum capsici) On Chili (Capsicum annuum) in In vitro. The research was done in the Laboratory Protection Plant Agriculture Faculty University of Medan Area, was held since Mei to July 2018. The research use Design Random Complete (RAL) Non Factorial with treatment F0 = negative control (PDA Media 100 %) F1 = Positive control (Synthetic fungicide 0.2%), F2 = 20% kenikir+ 10%betel, F3 = 30 % kenikir+ 10%betel,, F4 = 40% kenikir+ 10%betel, F5 = 20% kenikir+ 20%betel, F6 = 30 % kenikir+ 20%betel, F7 = 40% kenikir+ 20%betel, F8 = 20% kenikir+ 30%betel, F9 = 30% kenikir+ 30%betel, F10 = 40 % kenikir+ 30%betel. The results of the study: the tested extract of kenikir and betel leaf leaves showed the same results for inhibiting the growth of colony diameter and percentage of fungi growth.

scholarly journals OPTIMISATION OF GROWING CONDITIONS OF EUROPEAN MISTLETOE HYPERPARASITIC FUNGUS (PHAEOBOTRYOSPHAERIA VISCI): EFFECT OF DIFFERENT MEDIA AND ANTIBIOTICS / OPTIMALIZÁCIA RASTOVÝCH PODMIENOK PHAEOBOTRYOSPHAERIA VISCI, HYPERPARAZITICKEJ HUBY IMELA BIELEHO: VPLYV RÔZNYCH ŽIVNÝCH MÉDIÍ A ANTIBIOTÍK

2013 ◽  
Vol 16 (2) ◽  
pp. 44-47
Author(s):  
Ildikó Varga ◽  
Tivadar Baltazár ◽  
Miloš Pejchal
Keyword(s):  
Biocontrol Agent ◽  
Woody Species ◽  
Optimal Growth ◽  
Viscum Album ◽  
Potato Dextrose Agar ◽  
Oatmeal Agar ◽  
Colony Diameter ◽  
Mycelia Growth ◽  
Growing Conditions

Abstract European mistletoe (Viscum album) is an evergreen, perennial, hemiparasitic shrub, which is able to infect more than 450 woody species. Besides mechanical pruning, a hyperparasitic fungus (Phaeobotryosphaeria visci) could be a successful candidate to develop an effective biocontrol agent against mistletoe. It was necessary to find antibiotics which make the isolation easier and do not effect mycelia growth negatively under strain. Furthermore, we wanted to define a medium for optimal growth under in vitro laboratory conditions. Three different media (potato-dextrose agar, modified oatmeal agar, ¼ PDA + V8 agar) and four antibiotics (kanamycin, ampicillin, rifampicin, nystatin) were tested. Oatmeal agar and potato-dextrose agar are optimal to maintain the fungal strains, the colony diameter was 9 cm on the 12th day. All tested antibiotics are useful, except nystatin.

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