Effects of mesophilic and thermophilic composts on suppression of Fusarium root and stem rot of greenhouse cucumber

2000 ◽  
Vol 46 (11) ◽  
pp. 1021-1028 ◽  
Author(s):  
T Kannangara ◽  
R S Utkhede ◽  
J W Paul ◽  
Z K Punja
Keyword(s):  
Electrical Conductivity ◽  
Fusarium Oxysporum ◽  
Fungal Pathogen ◽  
Potato Dextrose Agar ◽  
Disease Suppression ◽  
Stem Rot ◽  
Stunted Growth ◽  
The Third ◽  
Colony Forming Units ◽  
Greenhouse Cucumber

Three composts were tested for their ability to suppress root and stem rot caused by the soil borne fungal pathogen Fusarium oxysporum f. sp. radicis-cucumerinum (FORC) on cucumber. Two of the composts were prepared from separated dairy solids either by windrow (WDS) or vermicomposting (VMC) while the third, obtained from International Bio-Recovery (IBR), was prepared from vegetable refuse using aerobic digestion. Three sets of potting mixes were prepared by mixing the composts with sawdust at varying ratios, and seeded with cucumber cv. Corona. After 14 days of growth in the greenhouse, inoculum of FORC (20 mL of 5 × 106micro-conidia per mL) was applied to each pot at three different times (14, 21, and 35 days). In unamended inoculated pots, the pathogen caused stunted growth and reduced flowers. Amendment of WDS in the potting mix suppressed these symptoms, while VMC and IBR had no effect. All three composts reduced the FORC colony forming units (cfu) at the end of the experiment (10 weeks). There was a large increase of fluorescent bacteria near the vicinity of roots particularly in WDS amended potting mixes. When water extracts of the composts were plated onto acidified potato dextrose agar (APDA), only IBR contained a potent thermostable inhibitor to FORC. This inhibitor was removed by activated charcoal but was not partitioned into petroleum ether at acid, basic, or neutral pH. Inhibition of FORC by IBR was not due to electrical conductivity or trace elements in the compost. Contrasting effectiveness of the WDS and VMC made from the same waste suggests that composting method can influence the disease suppression properties of the finished compost.Key words: Fusarium oxysporum f. sp. radicis-cucumerinum, biological control.

scholarly journals Greenhouse Cucumber Cultivars Differ in Susceptibility to Fusarium Root and Stem Rot

2004 ◽  
Vol 14 (2) ◽  
pp. 240-242 ◽  
Author(s):  
Steve Rose ◽  
Zamir K. Punja
Keyword(s):  
Fusarium Oxysporum ◽  
Disease Severity ◽  
Severity Index ◽  
Stem Rot ◽  
Disease Severity Index ◽  
Plant Mortality ◽  
Breeding Lines ◽  
The Third ◽  
Enhanced Resistance ◽  
Greenhouse Cucumber

Eighteen cucumber (Cucumis sativus L.) cultivars (long English type) were screened for their susceptibility to fusarium root and stem rot caused by Fusarium oxysporum Schlechtend.: Fr. f.sp. radicis-cucumerinum D.J. Vakalounakis using seedlings at the third true-leaf stage. Roots were trimmed and dipped into a spore suspension (105 spores/mL) of the pathogen and the plants were re-potted. A disease severity index (DSI) was used to assess disease responses 4 or 8 weeks later based on plant mortality and the height of surviving plants compared to the noninoculated controls. `Sienna', `Amazing' and `Dominica' were most susceptible to infection and the resulting DSI values were significantly (P ≤ 0.05) higher compared to noninoculated control plants. The cultivars `Korinda', `Euphoria' and `Aviance' displayed significantly lower DSI values which were not significantly different from noninoculated control plants. The remaining 12 cultivars displayed DSI values which were intermediate between the above two classes of responses. The results from this study indicate there is the potential to identify and develop cultivars and breeding lines of greenhouse cucumbers with enhanced resistance to fusarium root and stem rot.

Is Thermal and Light-Induced Annealing of Met Astable Defects in a-Si:H Driven by Electrons?

1995 ◽  
Vol 377 ◽  
Author(s):  
Helena Gleskova ◽  
S. Wagner
Keyword(s):  
Electrical Conductivity ◽  
Light Intensity ◽  
Defect Density ◽  
Hydrogenated Amorphous Silicon ◽  
Free Electrons ◽  
Free Electron Density ◽  
Independent Variables ◽  
The Third ◽  
Defect Annealing ◽  
Hydrogenated Amorphous

ABSTRACTWe report results of a search for a unifying rate law for the annealing of metastable defects in hydrogenated amorphous silicon (a-Si:H). We tested the hypothesis that defect-annealing by both heating or illumination is driven by the density of free electrons. This hypothesis is formulated via the rate equation - dN/dt = A nα N f (T), where N is the defect density, t the time, A a constant, n the free electron density, and f (T) a function of temperature derived from a distribution of annealing energies. The model fits two sets of data, with light-intensity and electrical conductivity as the independent variables, reasonably well, with a ranging from 0.39 to 0.76, but not the third set, where we varied the temperature.

scholarly journals Characterization of Fusarium oxysporum Isolates Obtained from Cucumber in China by Pathogenicity, VCG, and RAPD

Plant Disease ◽  
2004 ◽  
Vol 88 (6) ◽  
pp. 645-649 ◽  
Author(s):  
D. J. Vakalounakis ◽  
Z. Wang ◽  
G. A. Fragkiadakis ◽  
G. N. Skaracis ◽  
D.-B. Li
Keyword(s):  
Fusarium Oxysporum ◽  
Random Amplified Polymorphic Dna ◽  
Vegetative Compatibility ◽  
Stem Rot ◽  
Chinese Isolate ◽  
Vegetative Compatibility Group ◽  
Group I ◽  
Compatibility Group ◽  
First Time

Thirty-four isolates of Fusarium oxysporum, obtained in China from cucumber plants showing either Fusarium wilt (F. oxysporum f. sp. cucumerinum) or root and stem rot (F. oxysporum f. sp. radicis-cucumerinum) symptoms, were characterized by pathogenicity, vegetative compatibility, and random amplified polymorphic DNA (RAPD). Of these, 23 isolates were identified by pathogenicity as F. oxysporum f. sp. cucumerinum, and one as F. oxysporum f. sp. radicis-cucumerinum, while 10 isolates were avirulent on cucumber, melon, sponge gourd, and pumpkin. The Chinese isolates of F. oxysporum f. sp. cucumerinum were assigned to RAPD groups III and XXI and to vegetative compatibility group (VCG) 0183, four new VCGs, 0184 to 0187, and a single-member VCG included in the artificial VCG 018-. The Chinese isolate of F. oxysporum f. sp. radicis-cucumerinum was assigned to RAPD group I and bridging VCG 0260/0261. The occurrence of F. oxysporum f. sp. radicis-cucumerinum on cucumber is reported for the first time in China.

scholarly journals Keanekaragaman Kapang Patogen dan Non Patogen pada Imago, Kokon, dan Larva Instar Keenam Ulat Sutera Liar Attacus atlas (Lepidoptera: Saturniidae)

2019 ◽  
Vol 37 (2) ◽  
pp. 232
Author(s):  
Agustin Indrawati ◽  
Damiana Rita Ekastuti ◽  
Erdina Pangestika ◽  
Reinilda Alwina
Keyword(s):  
Aspergillus Fumigatus ◽  
Fusarium Oxysporum ◽  
Aspergillus Flavus ◽  
Microscopic Observation ◽  
Potato Dextrose Agar ◽  
Aspergillus Versicolor ◽  
Wild Silkworm ◽  
Opportunistic Pathogenic

Attacus atlas is one of several mould species in Indonesia known as kupu-kupu gajah. Information about variety of mould is rarely known. The purpose of this research was to obtain data about variety of pathogenic or non pathogenic mould at imago,cocoon, and sixth larvae phase of wild silkworm A. atlas. Mould was isolated from cocoon, integument, alimentary duct and reproduction duct of imago, trachea, midgut and hindgut, also haemolymph of larvae. Isolated mould was cultured on potato dextrose agar. Isolated mould from cocoon and imago was identified by macroscopic and microscopic observation. The results showed that there were two kind of moulds from cocoon which were Fusarium oxysporum  and Aspergillus flavus. There were four kind of moulds from imago A. atlas which were Aspergillus flavus, Aspergillus versicolor, Aspergillus fumigatus, Fusarium dimerum, and Aspergillus sp.There were three kind of moulds from sixth larvae which were Aspergillus fumigatus, Aspergillus flavus, and Fusarium dimerum. The mould which has opportunistic pathogenic for Attacus atlas were Fusarium oxysporum, Aspergillus  flavus, Aspergillus fumigatus and Fusarium dimerum.

scholarly journals KEEFEKTIFAN FORMULA MINYAK CENGKEH DAN SERAI WANGI TERHADAP Fusarium oxysporum f.sp. vanillae PENYEBAB BUSUK BATANG VANILI

2020 ◽  
Vol 18 (4) ◽  
pp. 143
Author(s):  
MESAK TOMBE ◽  
DARMAWAN PANGERAN ◽  
TRI SAPTARI HARYANI
Keyword(s):  
Fusarium Oxysporum ◽  
Soil Microorganisms ◽  
Soil Microorganism ◽  
Stem Rot ◽  
Clove Oil ◽  
Vanilla Planifolia ◽  
Green House ◽  
Microorganism Population

<p>ABSTRAK<br />Busuk batang vanili (BBV) yang disebabkan oleh Fusarium<br />oxysporum f.sp. vanillae (Fov) merupakan patogen penting pada vanili dan<br />menyebabkan kerugian besar setiap tahunnya di Indonesia. Jumlah<br />kerugian diperkirakan sebesar 3.000 ton atau sekitar US$ 16 juta.<br />Penelitian dilaksanakan di laboratorium dan rumah kaca Kelti Hama dan<br />Penyakit, Balai Penelitian Tanaman Rempah dan Obat, Bogor pada bulan<br />Februari 2010 sampai Agustus 2010. Tujuan penelitian adalah untuk<br />mengetahui pengaruh formula dengan bahan aktif minyak cengkeh dan<br />serai wangi terhadap penyakit BBV dan dampaknya terhadap kehidupan<br />mikroorganisme tanah. Dalam pelaksanaannya, kegiatan penelitian dilaku-<br />kan dalam 3 tahap yaitu : (1) uji formula in vitro, (2) uji formula in vivo,<br />dan (3) uji dampak formula terhadap mikroorganisme tanah. Percobaan<br />tahap 1, 2, dan 3 masing-masing terdiri atas 10, 6, dan 6 perlakuan,<br />dan.masing-masing disusun menggunakan rancangan acak lengkap dengan<br />3 ulangan. Materi yang dikaji dalam penelitian ini adalah (1) formula<br />dengan bahan aktif minyak cengkeh (formula standar), (2) formula dengan<br />bahan aktif minyak cengkeh dan serai wangi (formula baru), dan (3)<br />fungisida sintetis berbahan aktif mankozeb sebagai pembanding. Hasil uji<br />in vitro menunjukkan bahwa fungisida nabati CS (minyak cengkeh + serai<br />wangi) pada ke 3 tingkatan konsentrasi (terutama konsentrasi 400 ppm)<br />memperlihatkan efektivitas yang tinggi dalam menghambat pertumbuhan<br />miselium dan produksi spora patogen Fov.F117 dibandingkan perlakuan<br />lain dan kontrol. Hasil uji in vivo menunjukkan hal yang sama bahwa<br />fungisida nabati CS memperlihatkan efektivitas yang tinggi dalam<br />menekan intensitas serangan patogen BBV, terutama pada dosis aplikasi 5<br />ml/l. Dampak perlakuan terhadap kehidupan mikroorganisme tanah (fungi<br />dan bakteri) memperlihatkan bahwa penggunaan fungisida sintetis<br />mankozeb menghambat kehidupan mikroorganisme tanah 90-100% jika<br />dibandingkan dengan kontrol. Populasi mikroorganisme tanah pada semua<br />perlakuan fungisida nabati lebih tinggi jika dibandingkan dengan fungisida<br />mankozeb. Populasi mikroorganisme pada aplikasi fungisida nabati pada<br />dosis 5 ml/l tidak berbeda nyata dengan kontrol. Penelitian ini<br />menunjukkan bahwa penggunaan fungisida nabati minyak cengkeh<br />terutama jika dikombinasikan dengan minyak serai wangi mempunyai<br />prospek untuk digunakan dalam pengendalian penyakit BBV dengan<br />interval aplikasi 3-4 minggu sekali.<br />Kata kunci : Vanilla planifolia, Fusarium oxysporum f.sp, vanillae, busuk<br />batang vanili, minyak cengkeh, minyak serai wangi</p><p>ABSTRACT<br />Vanilla stem rot (VSR) disease caused by Fusarium oxysporum f.sp.<br />vanillae (Fov) is an important disease on vanilla and causes severe loss<br />annually in Indonesia. The total annual loss in production due to the VSR<br />was estimated to be 3,000 ton or about US$ 16 million. This research was<br />carried out in the laboratory and green house of Pest and Disease of<br />Research Institute for Spices and Medicinal Crops, Bogor from February<br />2010 until August 2010. The objective of this research was to study the<br />effect of formula using active compounds of clove and citronella oils on<br />the VSR disease and its impact on the survival of soil microorganisms.<br />The research activities were conducted in three stages, namely (1) in vitro<br />formula test; (2) in vivo formula test, and (3) impact test of formula on the<br />soil microorganisms. Materials studied in this research were (1) formula<br />with active compound of clove oil (standard), (2) formula with active<br />compound of clove and citronella oils (new formula), and (3) synthetic<br />fungicide with mancozeb active ingredient as comparison. Every phase of<br />this 3 stage experiment was arranged using completely randomized design<br />with three replicates. First, second, and third phases of the experiment<br />consisted of 10, 6, and 6 treatments, respectively. In vitro test results<br />carried out in the laboratory indicated that botanical formula CS (clove and<br />citronella oils of the three concentration levels, especially on the 400 ppm)<br />showed high effectiveness on inhibiting mycelium growth and spore<br />production of Fov.F117 pathogen compared to other treatments and<br />control. In vivo test in the green house indicated the same result that<br />botanical fungicide CS (clove dan citronella oils) showed high<br />effectiveness in suppressing VSR disease infection intensity, especially on<br />5 ml/l dosage. Application of mancozeb synthetic fungicide inhibited 90 –<br />100% soil microorganism livelihood compared to control. However, the<br />soil microorganism population on all botanical fungicides was higher than<br />on mancozeb fungicide. The microorganism population on the botanical<br />fungicide of 5 ml/l dosage was not significantly different from the control<br />(natural soil with no treatment). This research indicates that aplication of<br />botanical fungicide (combination between clove and citronella oils) with<br />3 - 4 weeks interval is prospectous to control VSR disease.<br />Key words : Vanilla planifolia, Fusarium oxysporum, f.sp. vanillae,<br />vanilla stem rot, clove oil, citronella oil</p>

scholarly journals The sss Colonization Gene of the Tomato-Fusarium oxysporum f. sp. radicis-lycopersici Biocontrol Strain Pseudomonas fluorescens WCS365 Can Improve Root Colonization of Other Wild-type Pseudomonas spp. Bacteria

2000 ◽  
Vol 13 (11) ◽  
pp. 1177-1183 ◽  
Author(s):  
Linda C. Dekkers ◽  
Ine H. M. Mulders ◽  
Claartje C. Phoelich ◽  
Thomas F. C. Chin-A-Woeng ◽  
André H. M. Wijfjes ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Pseudomonas Fluorescens ◽  
Pathogenic Fungus ◽  
Cell Types ◽  
Disease Suppression ◽  
Systemic Resistance ◽  
Root Tip ◽  
Wild Type ◽  
Tomato Root ◽  
Colonization Ability

We show that the disease tomato foot and root rot caused by the pathogenic fungus Fusarium oxysporum f. sp. radicis-lycopersici can be controlled by inoculation of seeds with cells of the efficient root colonizer Pseudomonas fluorescens WCS365, indicating that strain WCS365 is a bio-control strain. The mechanism for disease suppression most likely is induced systemic resistance. P. fluorescens strain WCS365 and P. chlororaphis strain PCL1391, which acts through the production of the antibiotic phenazine-1-carboxamide, were differentially labeled using genes encoding autofluorescent proteins. Inoculation of seeds with a 1:1 mixture of these strains showed that, at the upper part of the root, the two cell types were present as microcolonies of either one or both cell types. Microcolonies at the lower root part were predominantly of one cell type. Mixed inoculation tended to improve biocontrol in comparison with single inoculations. In contrast to what was observed previously for strain PCL1391, mutations in various colonization genes, including sss, did not consistently decrease the biocontrol ability of strain WCS365. Multiple copies of the sss colonization gene in WCS365 improved neither colonization nor biocontrol by this strain. However, introduction of the sss-containing DNA fragment into the poor colonizer P. fluorescens WCS307 and into the good colonizer P. fluorescens F113 increased the competitive tomato root tip colonization ability of the latter strains 16- to 40-fold and 8- to 16-fold, respectively. These results show that improvement of the colonization ability of wild-type Pseudomonas strains by genetic engineering is a realistic goal.

scholarly journals Resistance of Chinese asters (Callistephus chinensis Nees.) to Fusarium wilts (Fusarium oxysporum f. sp. callistephi (Beach) Snyder and Hansen) evaluated using artificial inoculations

2008 ◽  
Vol 35 (No. 4) ◽  
pp. 151-161 ◽  
Author(s):  
T. Nečas ◽  
F. Kobza
Keyword(s):  
Statistical Analysis ◽  
Fusarium Oxysporum ◽  
Root Systems ◽  
Mortality Rates ◽  
The Third ◽  
Botanical Species ◽  
Foreign Origin ◽  
Artificial Inoculations ◽  
Moderately Resistant ◽  
Fusarium Wilts

The resistance of Chinese asters to <I>Fusarium</I> wilt was tested by artificially inoculating the root systems. A mixture of <I>Fusarium</I> isolates was prepared with a concentration of about 10<sup>4</sup>–10<sup>9</sup> propagules per litre of the pathogen. 63 cultivars of both domestic and foreign origin were evaluated in the 1<sup>st</sup> year, 95 in the 2<sup>nd</sup> year and 89 in the 3<sup>rd</sup> year. Clear, statistically valid differences in mortality, both with experiments involving artificial inoculations and considering natural infections, make it possible to divide aster varieties into three groups based in their resistance to infections. The first set can be described as resistant. This includes the Matsumoto, Einf. Madeleine and Americká kráska series, and several others. The second set can be described as being moderately resistant. This includes the Chryzantémokvěté and Standy series, and the cultivars Matsumoto Pink, Princes Armida and Jitka. The third set can be described as sensitive. This includes the Průhonický trpaslík, Jehlicovité and Pastel series and several others. A statistical analysis of the results shows that the Einf. Madeleine series of cultivars is the most resistant to <I>Fusarium</I> wilt. This series is phenotypically similar to the original botanical species. Resistance was evaluated by recording the differences in mortality rates between artificially-inoculated plants and non-inoculated group (controls).

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