scholarly journals Indian Mustard and Allyl Isothiocyanate Inhibit Sclerotium rolfsii

2002 ◽  
Vol 127 (1) ◽  
pp. 27-31 ◽  
Author(s):  
Stephanie G. Harvey ◽  
Heather N. Hannahan ◽  
Carl E. Sams
Keyword(s):  
Treatment Effect ◽  
Radial Growth ◽  
Mycelial Growth ◽  
Sclerotium Rolfsii ◽  
Indian Mustard ◽  
Allyl Isothiocyanate ◽  
Potato Dextrose Agar ◽  
Soilborne Pathogen ◽  
Low Concentrations ◽  
Sclerotial Germination

Allyl isothiocyanate (AITC) is the predominant isothiocyanate produced by damaged tissues of Indian mustard (Brassica juncea (L) Czerniak). This study investigated Indian mustard and AITC mediated suppression of mycelial growth and sclerotial germination of Sclerotium rolfsii Saccardo, a common soilborne pathogen. Indian mustard (IM) treatments of 0, 0.1, 0.2, 0.6, 1.0, 2.0, 4.1, 5.1, 10.2, 20.4, 40.8, 81.6, and 163.3 g·L-1 (weight of reconstituted mustard per liter of air) were evaluated for suppression of mycelial growth. Treatment effect was evaluated by measuring the radial growth of mycelia. Sclerotia were placed in culture tubes containing 18 g autoclaved soil and covered with an additional 5 g soil. AITC at concentrations of 0, 4.0, 16.0, 64.0, 256.0, 1024.0, or 4096.0 μmol·L-1 was injected into the tubes. Treated sclerotia were removed from tubes and plated on potato dextrose agar to determine viability. Mycelial growth was inhibited with IM treatments (P < 0.01). Inhibiting concentrations (IC) of IM for mycelial growth inhibition of 50% and 90% were 0.7 and 1.0 g·L-1, respectively, with death resulting with >2 g·L-1. Inhibition attributable to AITC alone was lower than that achieved by IM producing equivalent amounts of AITC. Germination of sclerotia was negatively correlated with AITC concentration (r = 0.96; P < 0.01). The IC50 and IC90, of AITC were 249.0 and 528.8 μmol·L-1, respectively, at 42 hours. The lethal concentration for sclerotia was not reached; only suppression occurred at the highest treatment concentrations. Sclerotium rolfsii mycelia were sensitive to the IM volatiles and were suppressed at low concentrations. Sclerotia were more resistant than the mycelia and required higher concentrations of AITC to suppress germination.

scholarly journals Effect of Different Carbon and Nitrogen Sources on Sclerotium rolfsii sacc. Mycelial Growth and Sclerotial Development

2020 ◽  
Vol 9 (1) ◽  
pp. 17-27
Author(s):  
Fakher Ayed ◽  
Hayfa Jabnoun-Khiareddine ◽  
Rania Aydi-Ben Abdallah ◽  
Mejda Daami-Remadi
Keyword(s):  
Ammonium Chloride ◽  
Radial Growth ◽  
Mycelial Growth ◽  
Sodium Citrate ◽  
Ammonium Acetate ◽  
Sclerotium Rolfsii ◽  
N Source ◽  
Sclerotial Formation ◽  
Sclerotial Development ◽  
Sclerotial Germination

In vitro studies were conducted on Potato Dextrose Agar using different carbon (C) and nitrogen (N) sources to evaluate their effects on the mycelial growth, and the sclerotial development of three Tunisian Sclerotium rolfsii Sacc. isolates. Radial growth was optimum on basal medium supplemented with ammonium chloride (0.48 gram of nitrogen per liter (g of N.L-1)) as N source but was restricted on L-Arginine and completely inhibited on ammonium acetate amended media (0.48 g N.L-1). Sclerotial initiation occurred from the 3rd to the 12th day of incubation for all tested isolates. Potassium nitrate was the most suitable N source for sclerotial formation whereas sclerotial development was completely inhibited on ammonium acetate amended medium. Optimal sclerotial germination was recorded using L-Arginine (78-80%) followed by L-Asparagine (46-94%) and ammonium chloride (46-88%) as N sources. Nevertheless, the lowest sclerotial germination rate was noted on sodium nitrate and ammonium acetate amended media. As for C sources (16 gram of carbon per liter (g of C.L-1)), optimal radial growth occurred using D-mannitol for Sr1 and Sr2 isolates and maltose for Sr3, but no mycelial growth was recorded using sodium citrate for all isolates. All C sources tested, except sodium citrate, were suitable for sclerotial formation, production, and germination. Mature sclerotia became brownish after 6 to 12 days of incubation and sclerotial production was highest using D-mannitol, maltose, and D-glucose, depending on isolates used, as C sources. Optimal germination of sclerotia was noted using D-glucose, D-mannitol and maltose for Sr1 isolate, maltose for Sr2 and D-glucose and maltose for Sr3. It was concluded that N and C sources are both important factors for the growth of S. rolfsii and its survival.

scholarly journals 401 Effects of Allyl Isothiocyanate on Mycelial Growth from Germinating Sclerotia of Sclerotium rolfsii

HortScience ◽  
2000 ◽  
Vol 35 (3) ◽  
pp. 462A-462
Author(s):  
Stephanie G. Harvey ◽  
Carl E. Sams
Keyword(s):  
Mycelial Growth ◽  
Field Experiments ◽  
Field Isolate ◽  
Sclerotium Rolfsii ◽  
Indian Mustard ◽  
Allyl Isothiocyanate ◽  
Field Capacity ◽  
Volatile Chemicals ◽  
Mesh Bags ◽  
Loam Soil

Isothiocyanates are volatile chemicals produced by damaged tissues of Brassica species. Allyl isothiocyanate (AITC), the predominant isothiocyanate in Indian mustard (B. juncea), has been shown to control pest in laboratory and field experiments. We investigated the effectiveness of AITC against the germination of sclerotia of Sclerotium rolfsii Saccardo, a common soilborne pathogen of tomato. Sclerotium rolfsii was cultured on PDA from a field isolate. Mature sclerotia were collected and placed in polyester mesh bags. Culture tubes (16 × 150 mm) were packed with 18 g clay loam soil. A sclerotia-bag was placed in each tube and covered with an additional 5 g soil. Soil was maintained at 60% field capacity for the duration of the experiment. AITC was injected into each tube through a septum. Treatments consisted of 0, 5.6, 11.2, 22.4, and 44.8 μmol AITC/L of atmosphere and an ethanol control. AITC in each tube was sampled using SPME and analyzed on GC-MS. Tubes remained sealed for 42 h at 30 °C. Sclerotia were then removed from tubes and bags and plated on PDA to determine viability. Radial growth was measured to determine the effects of AITC. Mycelial growth was negatively correlated to AITC concentration (P < 0.01). The highest concentration of AITC resulted in a 40.3% reduction in mycelial growth. Although the AITC concentrations used in this study did not kill sclerotia of S. rolfsii, they did suppress mycelial growth from germinating sclerotia. At higher concentrations, or mixed with other chemicals, AITC may prove to be an affective control for this pathogen.

Inhibition of Fungal Growth by Macerated Plant Tissues in a Closed Environment

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 476e-476
Author(s):  
Craig S. Charron ◽  
Catherine O. Chardonnet ◽  
Carl E. Sams
Keyword(s):  
Radial Growth ◽  
Fungal Pathogens ◽  
Solid Phase ◽  
Indian Mustard ◽  
Fungal Growth ◽  
Allyl Isothiocyanate ◽  
Pythium Ultimum ◽  
Alternative Methods ◽  
Gas Chromatography Mass Spectrometry ◽  
Clean Air

The U.S. Clean Air Act bans the use of methyl bromide after 2001. Consequently, the development of alternative methods for control of soilborne pathogens is imperative. One alternative is to exploit the pesticidal properties of macerated tissues of Brassica spp. This study tested the potential of several Brassica spp. for control of fungal pathogens. Pythium ultimum Trow or Rhizoctonia solani Kühn plugs on potato-dextrose agar on petri dishes were sealed in 500-ml glass jars (at 22 °C) containing macerated leaves (10 g) from one of six Brassica spp. Radial growth was measured 24, 48, and 72 h after inoculation. Indian mustard (B. juncea) was the most suppressive, followed by `Florida Broadleaf' mustard (B. juncea). Volatile compounds in the jars were sampled with a solid-phase microextraction device (SPME) and identified by gas chromatography-mass spectrometry (GC-MS). Allyl isothiocyanate (AITC) comprised over 90% of the total volatiles measured from Indian mustard and `Florida Broadleaf' mustard. Isothiocyanates were detected in jars with all plants except broccoli. (Z)-3-hexenyl acetate was emitted by all plants and was the predominant volatile of `Premium Crop' broccoli (B. oleracea L. var. italica), `Michihili Jade Pagoda' Chinese cabbage (B. pekinensis), `Charmant' cabbage (B. oleracea L. var. capitata), and `Blue Scotch Curled' kale (B. oleracea L. var. viridis). To assess the influence of AITC on radial growth of P. ultimum and R. solani, AITC was added to jars to give headspace concentrations of 0.10, 0.20, and 0.30 mg·L–1 (mass of AITC per volume of headspace). Growth of both fungi was inhibited by 0.10 mg·L–1 AITC. 0.20 mg·L–1 AITC was fungicidal to P. ultimum although the highest AITC level tested (0.30 mg·L–1) did not terminate R. solani growth. These results indicate that residues from some Brassica spp. may be a viable part of a soilborne pest control strategy.

scholarly journals Effects of pH and Aeration on Sclerotium rolfsii sacc. Mycelial Growth, Sclerotial Production and Germination

2018 ◽  
Vol 7 (3) ◽  
pp. 123-129 ◽  
Author(s):  
Fakher Ayed ◽  
Hayfa Jabnoun-Khiareddine ◽  
Rania Aydi-Ben-Abdallah ◽  
Mejda Daami-Remadi
Keyword(s):  
Mycelial Growth ◽  
Sclerotium Rolfsii ◽  
Dry Weight ◽  
Ph Values ◽  
Effects Of Ph ◽  
Ph Range ◽  
Sclerotial Development ◽  
Sclerotial Germination

Sclerotium rolfsii is one of the devastating soilborne fungus responsible for significant plant losses. The effects of pH and aeration on pathogen mycelial growth, sclerotial production and germination were investigated for three Tunisian isolates. Optimal mycelial growth occurred at pH 6 for Sr2 and Sr3 isolates and at pH 6-7 for Sr1. Dry mycelial growth was optimum at pH values ranging between 4 and 7. Sclerotial initiation started on the 3rd day of incubation at all pH values tested and mature sclerotia were formed after 6 to 12 days. Optimal sclerotial production was noted at pH 5. The dry weight of 100 sclerotia varied depending on isolates and pH and occurred at pH range 4-7. At pH 9, mycelial growth, sclerotial production and dry weight of 100 sclerotia were restricted. The optimum sclerotial germination, noted after 24 h of incubation, varied depending on isolates and pH and occurred at pH 4-9. Mycelial growth was optimum in aerated plates with a significant isolates x aeration treatments interaction. Sclerotial initiation occurred at the 3rd day of incubation and mature sclerotia were observed after 6-9 days. Sclerotial development was very slow in completely sealed plates and dark sclerotia were produced only after 15 days of incubation. The highest sclerotial yields were noted in aerated plates. The highest dry weight of 100 sclerotia for Sr1 isolate was recorded in ½ sealed, no sealed and completely sealed plates, while for Sr2, it was noted in ½ and ⅔ sealed plates. For Sr3, the maximum dry weight of 100 sclerotia was recorded in ½, ⅔ and completely sealed plates. Germination of S. rolfsii sclerotia, after 24 h of incubation, did not vary significantly depending on aeration treatments and ranged from 90 to 100% for all isolates.

scholarly journals Effect of Osmotic and Matric Potentials on Sclerotinia minor and Sclerotinia sclerotiorum Virulence on Peanut

2016 ◽  
Vol 4 (3) ◽  
pp. 147-158 ◽  
Author(s):  
Ahmed Abd-Elmagid ◽  
Robert Hunger ◽  
Carla Garzón ◽  
Mark Payton ◽  
Ho-Jong Ju ◽  
...  
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Vegetative Growth ◽  
Mycelial Growth ◽  
Potato Dextrose Agar ◽  
Matric Potential ◽  
Progress Curve ◽  
High Concentrations ◽  
Matric Stress ◽  
Osmotic Potentials ◽  
Sclerotial Germination

The effect of osmotic and matric potentials on mycelial growth, sclerotia production, germination, and virulence of two isolates of Sclerotinia sclerotiorum, and one isolate of S. minor were studied on potato dextrose agar (PDA) media adjusted with KCl, glycerol, or agar. Osmotic potentials created by KCl and glycerol significantly reduced vegetative growth of the three isolates. On matrically adjusted PDA, vegetative growth of the three isolates was not negatively affected by matric stress up to -3.5 MPa. When KCl was the osmoticum, sclerotia number did not follow a consistent pattern. However, sclerotia number decreased when osmotic stress created by glycerol was increased. Matric stress was not a consistent factor affecting sclerotia production by both species.  However, the highest levels of matric stress -3.0 and -3.5 MPa significantly reduced sclerotia production by both species. In general, there was a trend toward lower sclerotial germination with increasing osmotic and matric stress. Pathogenicity of S. minor and S. sclerotiorum on the peanut cultivar (Okrun) was reduced by high concentrations of KCl. Mycelia of both species produced at high matric potential -3.5 MPa did not differ in pathogenicity on Okrun compared with mycelia grown on non-amended PDA. In water-stressed-Okrun, induced by polyethylene glycol 8000, the Area under Disease Progress Curve (AUDPC) was significantly decreased. The relevance of these results to the behavior of S. minor and S. sclerotiorum, and their pathogenicity on peanut is discussed.

scholarly journals Variations In Different Isolates Of Rhizoctonia Solani Based On Temperature And pH

1970 ◽  
Vol 36 (3) ◽  
pp. 389-396 ◽  
Author(s):  
BK Goswami ◽  
MM Rahaman ◽  
AKMA Hoque ◽  
K Bhuiyan ◽  
IH Mian
Keyword(s):  
Growth Factors ◽  
Rhizoctonia Solani ◽  
Radial Growth ◽  
Mycelial Growth ◽  
Potato Dextrose Agar ◽  
Optimum Temperature ◽  
Optimum Ph ◽  
Sclerotial Formation ◽  
Rates Of Growth ◽  
Different Levels

An experiment was conducted to find out variation in isolated Rhizoctonia solani based on radial mycelial growth and sclerotial production. Five isolates of Rhizoctonia solani representing five clusters group were selected and were grown at different levels of temperature and pH on potato dextrose agar (PDA). It was observed that optimum temperature and pH for growth and scierotial production varied among the isolates. The rates of growth and sclerotial formation were not uniform at the same levels of the two growth factors. The maximum mycelial growth of all isolates was found at 30°C. At 35°C, only GAZ-9 and GAZ-18 showed initiation of growth, but the rate was very slow. The optimum temperature for sclerotial production of the isolates GAZ-9, JES- 16, GAZ-18 SYL-26 was 30°C and for the isolate DIN-8 was 25°C. The optimum pH for maximum radial growth was 6 for DIN-8 and 7 for other four isolates. The maximum number of sclerotia was produced by DIN-8, GAZ-9, and SYL-30 at pH 8, 4, and 7, respectively. The optimum pH for sclerotia formation in JES-16 and GAZ-18 was pH 6. Keywords: Rhizoctonia solani; variations; temperature; pH. DOI: http://dx.doi.org/10.3329/bjar.v36i3.9267 BJAR 2011; 36(3): 389-396

scholarly journals Effect of organic amendments on sclerotial germination, mycelial growth, and Sclerotium rolfsii-induced diseases

2004 ◽  
Vol 29 (1) ◽  
pp. 66-74 ◽  
Author(s):  
Luiz E. B Blum ◽  
Rodrígo Rodríguez-Kábana
Keyword(s):  
Mycelial Growth ◽  
Disease Incidence ◽  
Sclerotium Rolfsii ◽  
Organic Amendments ◽  
Pinus Elliottii ◽  
Pine Bark ◽  
Pueraria Lobata ◽  
Trichoderma Sp ◽  
Amend Soil ◽  
Sclerotial Germination

The addition of organic residues to soil is an option to control some soil-borne diseases. Benzaldehyde and powders of kudzu (Pueraria lobata), velvetbean (Mucuna deeringiana), and pine-bark (Pinus elliottii and P. taeda) added to soil could reduce certain soil-borne diseases. This study evaluated the effects of benzaldehyde and the dried powders of kudzu, velvetbean, and pine-bark as soil amendments on germination and formation of sclerotia, on mycelial growth of Sclerotium rolfsii, on plant survival, and disease incidence. The data showed that high amounts of benzaldehyde (0.4 ml kg-1 of soil) and velvetbean (100 g kg-1) inhibited S. rolfsii mycelial growth and sclerotium germination. However, low amounts of benzaldehyde (0.1 ml kg-1), kudzu (25 g kg-1), and pine-bark (25 g kg-1) stimulated mycelial growth and sclerotium germination. Kudzu (25-100 g kg-1) and velvetbean (25-100 g kg-1) inhibited the formation of sclerotia. Nevertheless, benzaldehyde at 0.2 and 0.4 ml kg-1 stimulated the formation of sclerotia. Kudzu (50 and 100 g kg-1) and pine-bark (50 g kg-1) favored the colonization of sclerotia by Trichoderma sp. The numbers of soybean (Glycine max) plants were higher and diseased plants were lower than the non-amend soil in the following treatments: kudzu (50 and 100 g kg-1), velvetbean (50 and 100 g kg-1), and pine-bark (50 g kg-1). Disease severity on tomato (Lycopersicon esculentum) plants was low in soil treated with kudzu or velvetbean (30 and 35 g kg-1) and pine-bark (35 g kg-1). Dried powders of kudzu, velvetbean, or pine-bark added to soil can reduce disease by reducing pathogen inoculum.

scholarly journals Development of Sclerotia and Apothecia of Sclerotinia sclerotiorum from Infected Soybean Seed and Its Control by Fungicide Seed Treatment

Plant Disease ◽  
1999 ◽  
Vol 83 (12) ◽  
pp. 1113-1115 ◽  
Author(s):  
D. S. Mueller ◽  
G. L. Hartman ◽  
W. L. Pedersen
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Radial Growth ◽  
Mycelial Growth ◽  
Seed Treatment ◽  
Soybean Seed ◽  
Potato Dextrose Agar ◽  
Field Soil ◽  
Laboratory Studies ◽  
Infected Seed ◽  
Seed Coats

Field and laboratory studies were done to evaluate the development of sclerotia and apothecia of Sclerotinia sclerotiorum from soybeans and its control with fungicide seed treatment. Soybean seed infected with S. sclerotiorum produced mycelia on both seed coats and cotyledons after 48 h on potato dextrose agar (PDA). Obviously infected soybean seed also were placed in aluminum pans containing field soil and placed in soybean fields near Urbana, Illinois and Clinton, Wisconsin. In 1997, a total of 553 sclerotia, 20 stipes, and 10 apothecia were produced from 500 infected seeds. In 1998, 201 sclerotia and 22 stipes were produced, but no apothecia were observed from the 500 infected seeds. Fludioxonil was the most effective fungicide for reducing radial growth of S. sclerotiorum on PDA plates and suppressed 99% of the radial growth at 0.1 μg a.i./ml. S. sclerotiorum was recovered from 2% of soybean seed lots containing infected seed. When this seed lot was treated with several fungicides, captan + pentachloronitrobenzene + thiabendazole and fludioxonil completely inhibited mycelial growth from infected seed; thiram and thiabendazole each reduced recovery of S. sclerotiorum by 90%. In the field, 754 sclerotia and 10 apothecia were produced from 1,000 infected seeds over a two-year period. When evaluating fungicide control in the field, thiram, fludioxonil, and captan + pentachloronitrobenzene + thiabendazole reduced sclerotia formation from infected seed by more than 98%.

scholarly journals Evaluation of Some Fungicides against Collar Rot Disease of Soybean

2020 ◽  
pp. 159-166
Keyword(s):  
Mycelial Growth ◽  
Sclerotium Rolfsii ◽  
Potato Dextrose Agar ◽  
University Campus ◽  
Pathology Laboratory ◽  
Collar Rot ◽  
Soybean Plants ◽  
Rot Disease

A number of selected fungicides were evaluated to determine their efficacy for controlling collar rot disease of soybean plants caused by Sclerotium rolfsii. The experiment was conducted under the controlled condition at the Plant Pathology Laboratory and Field laboratory of BINA, Bangladesh Agricultural University campus from November 2018 to August 2019. In-vitro research was done for the observation of radial mycelial growth of S. rolfsii on potato dextrose agar (PDA), treated with five fungicides viz. Antracol 70 WP (T1), Ridomil Gold MZ 68 WP (T2), Secure 600 WG (T3), Bavistin DF (T4), Dithane M-45 (T5), and one non-treated (T0) treatment. The highest percentage of mycelial growth inhibition of S. rolfsii in PDA medium was recorded in treatment T5 (Dithane M-45) 100% and lowest in treatment T3 (Secure 600 WG) 37.33% at 6 days after inoculation. Then the selected five fungicides were again applied to pot under controlled conditions to observe the best effect of selected fungicides against collar rot pathogen of soybean plants. The inoculation was done on a variety of BINA soybean 4 in pot condition. The highest mortality percent for the collar rot disease was found in treatment T0 (controlled) 100% soybean plants conversely, the lowest mortality percent was found in treatment T5 (Dithane M-45) 27.28% besides 38.92% in T2 (Ridomil Gold MZ 68 WP), 43.42% in T1 (Antracol 70 WP), 46.18% in T3 (Secure 600 WG) and 50.00% in treatment T4 (Bavistin DF) respectively. Thus, Dithane M-45 was found superior in controlling collar rot pathogen S. rolfsii of Soybean over all other fungicides tested in both in vitro and in vivo.

Activity of Tolclofos - Methyl (Rizolex) on Sclerotium rolfsii and Rhizoctonia solani in Peanut1

1985 ◽  
Vol 12 (1) ◽  
pp. 32-35 ◽  
Author(s):  
A. S. Csinos
Keyword(s):  
Rhizoctonia Solani ◽  
Radial Growth ◽  
Sclerotium Rolfsii ◽  
Field Tests ◽  
Relative Activity ◽  
Stem Rot ◽  
Sclerotial Germination

Abstract Tolclofos-methyl was compared to PCNB in vitro to determine its relative activity against four isolates of Sclerotium rolfsii Sacc. and two isolates of Rhizoctonia solani Kuehn. Concentrations of 0.001, 0.01, 0.1, 1.0 and 10 μg/mL of each of the fungicides were used to evaluate their effects on radial growth on both S. rolfsii and R. solani and their effects on sclerotia formation and sclerotial germination of S. rolfsii. Little difference in efficacy between the fungicides occurred for S. rolfsii. However, tolclofos-methyl reduced radial growth of R. solani more than PCNB at concentrations of 0.1 and 1.0 μg/mL. In field tests in 1982 and 1984 tolclofos-methyl at 5.6 kg ai/ha or less was as effective or superior to PCNB or PCNB-fensulfothion in reducing incidence of southern stem rot and increasing yield. In 1984, tolclofos-methyl at 8.4 kg ai/ha reduced Rhizotonia limb rot damage over the control, but PCNB at 11.2 kg ai/ha did not.

Sign in / Sign up

Export Citation Format

Share Document