Biological control of ground nut stem rot fungus, Sclerotium rolfsii (Sacc.) by Streptomyces Violaceusniger along with organic ammendments

Stem rot of groundnut caused by Sclerotium rolfsii, seriously damages groundnut production in central Vietnam. Biological control is a promising strategy for sustainable groundnut cultivation. In this study, indigenous bacteria were isolated from the rhizosphere of groundnut and tested for fungal inhibition against S. rolfsii in vitro and disease control under net house condition. Genetic diversity of isolated bacterial population was evaluated by BOX-PCR and 16S rDNA sequences. Bacterial strains that showed high disease control in net house were evaluated under natural conditions in farmer fields. The antifungal mechanism of the best bacterial strain was identified. Results of the study showed that the antagonistic bacterial population in groundnut rhizosphere is separated in three bacterial genera including Bacillus, Pseudomonas and Burkholderia. One bacterial strain which produces 2,4-DAPG reduced stem rot of groundnut caused by S. rolfsii and increased yield from 20.3 to 26.3% compared to the control.

Download Full-text

Biological control of Sclerotinia stem rot of soybean with Sporidesmium sclerotivorum

10.31274/rtd-180813-13923 ◽

1999 ◽

Author(s):

Luis Enrique del Rió Mendoza

Keyword(s):

Biological Control ◽

Stem Rot ◽

Sclerotinia Stem Rot

Download Full-text

A Comparison of Disease Assessment Methods for Southern Stem Rot of Peanut

Peanut Science ◽

10.3146/pnut.29.1.0012 ◽

2002 ◽

Vol 29 (1) ◽

pp. 66-71 ◽

Cited By ~ 4

Author(s):

S. L. Rideout ◽

T. B. Brenneman ◽

K. L. Stevenson

Keyword(s):

Alternative Assessment ◽

Disease Incidence ◽

Sclerotium Rolfsii ◽

Correlation Coefficients ◽

Assessment Method ◽

Assessment Methods ◽

Alternative Methods ◽

Stem Rot ◽

Disease Assessment ◽

Time Required

Abstract Southern stem rot (caused by the soilborne fungus Sclerotium rolfsii Sacc.) of peanut (Arachis hypogaea L.) traditionally has been assessed based on the percentage of infected 30.5-cm row segments, commonly referred to as disease incidence. Several alternative disease assessment methods were evaluated in four fungicide trials during the growing season (aboveground ratings) and immediately after peanut inversion (belowground ratings). Pearson's correlation coefficients compared disease assessments and yields for all trials. Across all disease assessment methods, belowground assessments at inversion showed a stronger correlation with yield than in-season aboveground assessments. Several of the alternative assessment methods showed a stronger negative correlation with yield than did the traditional disease incidence rating. However, none of the alternative methods were consistently more precise across all assessment dates and trials. There was a significant positive correlation between many of the alternative methods and the traditional disease incidence method. Furthermore, none of the alternative methods was better than the traditional method for detecting differences among fungicide treatments when subjected to ANOVA and subsequent Waller-Duncan mean separation tests (k-ratio = 100). Based on comparisons of the time required to assess disease intensity, the traditional disease assessment method was found to be the most time efficient method of those tested in this study.

Download Full-text

Production of lytic enzymes by Trichoderma strains during in vitro antagonism with Sclerotium rolfsii, the causal agent of stem rot of groundnut

African Journal of Microbiology Research ◽

10.5897/ajmr2014.7330 ◽

2015 ◽

Vol 9 (6) ◽

pp. 365-372 ◽

Cited By ~ 8

Author(s):

J Parmar H ◽

P Bodar N ◽

N Lakhani H ◽

V Patel S ◽

V Umrania V ◽

...

Keyword(s):

Sclerotium Rolfsii ◽

Causal Agent ◽

Stem Rot ◽

Lytic Enzymes

Download Full-text

Soil-Borne Pests of Peanut in Growers' Fields with Different Cropping Histories in Alabama1

Peanut Science ◽

10.3146/i0095-3679-23-1-7 ◽

1996 ◽

Vol 23 (1) ◽

pp. 36-42 ◽

Cited By ~ 8

Author(s):

K. L. Bowen ◽

A. K. Hagan ◽

J. R. Weeks

Keyword(s):

Aspergillus Flavus ◽

Meloidogyne Incognita ◽

Leaf Spot ◽

Sclerotium Rolfsii ◽

Stem Rot ◽

Peanut Seed ◽

Control Programs ◽

Aflatoxigenic Fungi ◽

Peanut Production ◽

Seed Invasion

Abstract Pest levels and yields of peanut were monitored in growers' fields in 1991 through 1993. Yields ranged from 2085 to 6440 kg/ha and averaged 3947 kg/ha over the 3 yr. Incidence of southern stem rot (SSR) (caused by Sclerotium rolfsii) averaged 7.6 foci (up to 30 cm in length) per 30.5 m row and ranged from 0 to 31.0 foci. Peanut yield tended to be inversely related to incidence of SSR and directly related to the number of years between peanut crops. Incidence of SSR was inversely related to number of years between peanut crops and was consistently greater in fields cropped to peanut every other year compared to other fields with less intensive peanut production. Yields obtained from irrigated fields averaged 11.4% greater than those without irrigation. Leaf spot control programs used by growers provided consistent levels of control. Peanut seed invasion by aflatoxigenic fungi and plant damage by larvae of the lesser cornstalk borer (Elasmopalus lignosellus) generally were low. Seed invasion by Aspergillus flavus-type fungi was positively correlated (P < 0.05) with damage due to lesser cornstalk borer in 1993. Juvenile populations of root knot nematodes (Meloidogyne incognita) were positively correlated (P < 0.001) with incidence of SSR in 1992.

Download Full-text

On-Farm Evaluations of Reduced Input Fungicide Programs in Peanut Fields with Low, Moderate, or High Levels of Disease Risk

Peanut Science ◽

10.3146/ps11-23r2.1 ◽

2014 ◽

Vol 41 (1) ◽

pp. 50-57 ◽

Cited By ~ 6

Author(s):

J. E. Woodward ◽

T. B. Brenneman ◽

R. C. Kemerait ◽

A. K. Culbreath ◽

N. B. Smith

Keyword(s):

Leaf Spot ◽

Cultural Practices ◽

Disease Risk ◽

Sclerotium Rolfsii ◽

Stem Rot ◽

Cercospora Arachidicola ◽

Production Region ◽

Net Returns ◽

Peanut Production ◽

On Farm

ABSTRACT In 2003, 2004, and 2005 standard and reduced input fungicide programs were evaluated throughout the peanut production region of Georgia for control of early leaf spot (Cercospora arachidicola), late leaf spot (Cercosporidium personatum), and southern stem rot (Sclerotium rolfsii). Disease risk was determined for each field based on the cultural practices implemented and ranged from low to high. Six to eight fungicide applications were made in the standard programs, versus three to six applications in reduced programs. Leaf spot ratings were higher for the reduced programs in five of the fourteen trials with substantial defoliation occurring in one trial. Overall, southern stem rot control for the reduced programs was equal to or better than that for the standard program, which could be attributed to the differences in fungicide selection or timing. Pod yields for the reduced programs were equal to or greater than the standard programs in all but one trial. Net returns were higher for the reduced programs in half of the trials; however, the reduced program resulted in lower net returns in one trial in 2004. Our results indicate that reduced input fungicide programs can be used to adequately manage fungal diseases of peanut without compromising yield or profitability, and that the use of cultivars with moderate levels of disease resistance may enhance disease control.

Download Full-text

Potential for Improved Control of Southern Stem Rot of Peanut with Resistance and Fungicides1

Peanut Science ◽

10.3146/pnut.12.1.0002 ◽

1985 ◽

Vol 12 (1) ◽

pp. 4-7 ◽

Cited By ~ 1

Author(s):

B. B. Shew ◽

M. K. Beute ◽

J. E. Bailey

Keyword(s):

North Carolina ◽

Disease Resistance ◽

Arachis Hypogaea ◽

Sclerotium Rolfsii ◽

Stem Rot ◽

Arachis Hypogaea L ◽

Disease Loci ◽

Moderate Resistance

Abstract Potential for improved control of southern stem rot caused by Sclerotium rolfsii Sacc.on peanut (Arachis hypogaea L.) was evaluated by combining moderate resistance with fungicide use. Various fungicides including carboxin, oxycarboxin, propiconazol, OAC 3890, and PCNB were applied to peanut lines NC 8C, NC Ac 18016, and Florigiant in North Carolina during 1980, 1981, and 1982. Consistently fewer disease loci occurred on NC Ac 18016 than on NC 8C or Florigiant. At least one fungicide reduced stem rot incidence in two of three years tested, but fungicide use did not result in greater yields. Effects of disease resistance and fungicides on suppression of stem rot development were additive.

Download Full-text