Control of Seed Transmission of Cylindrocladium parasiticum in Peanut with Seed Treatment Fungicides

Seeds of peanut cultivars VA 98R and NC-V 11 with speckled testae were treated with fungicide and assayed on a selective medium to determine the viabil­ ity of Cylindrocladium parasiticum. The fungus was isolated from 78 and 90% of the untreated speckled seed of the respective cultivars. Seed treatment with captan + pcnb + carboxin, fludioxonil, captan, and thio­ phanate methyl Significantly reduced recovery of the pathogen in both cultivars. Speckled seed of VA 98R and NC-V11 were treated with fungicides and planted in greenhouse and/or field trials in Suffolk, VA. Plants became infected with C. parasiticum after treated and untreated speckled seed were planted in steam-treated soil in the greenhouse. In one trial, seed treatment with fludioxonil, tebuconazole, and LS 176 significant­ 1y reduced taproot colonization by C. parasiticum com­ pared to the untreated check. In a second greenhouse trial, only fludioxonil provided significant suppression of disease. In the field, treatment with fludioxonil, thi­ ram, and tebuconazole Significantly lowered Cylindrocladium black rot (CBR) incidence compared to the untreated check. Thiram Significantly reduced taproot colonization compared to all treatments except fludioxonil. Based on the present study, the addition of thiram and/or fludioxonil to the standard treatment of captan + pcnb + carboxin may offer the best protection against seed transmission of C. parasiticum.

[1]  P. Phipps,et al.  Incidence and Survival of Cylindrocladium parasiticum in Peanut Seed. , 2003, Plant disease.

[2]  M. K. Beute,et al.  Seed Transmission of Cylindrocladium parasiticum in Peanut. , 2001, Plant disease.

[3]  D. L. Glenn.  Incidence and Management of Seed Transmission of Cylindrocladium Black Rot of Peanut in Virginia , 2001 .

[4]  P. Crous,et al.  Cylindrocladium parasiticum sp. nov., a new name for C. crotalariae , 1993 .

[5]  D. M. Porter,et al.  Colonization of peanut seed by Cylindrocladium crotalariae , 1991 .

[6]  P. Phipps.  Control of Cylindrocladium black rot of peanut with soil fumigants having methyl isothiocyanate as the active ingredient. , 1990 .

[7]  D. M. Porter,et al.  Importance of Seed Transmission in The Spread of Cylindrocladium Crotalariae1 , 1986 .

[8]  D. Krigsvold.  Microsclerotial Germination ofCylindrocladium crotalariaein the Rhizospheres of Susceptible and Resistant Peanut Plants , 1982 .

[9]  P. Phipps.  Population Dynamics of Cylindrocladium crotalariae Microsclerotia in Naturally-Infested Soil , 1979 .

[10]  P. Phipps.  Influence of Soil Temperature and Moisture on the Severity of Cylindrocladium Black Rot in Peanut , 1977 .

[11]  W. T. Thomson.  Agricultural Chemicals, Book IV. Fungicides , 1992 .

[12]  R. Rowe.  Formation and Dispersal of Cylindrocladium crotalariae Microsclerotia in Infected Peanut Roots , 1974 .

[13]  D. Bel,et al.  A Peg, Pod, and Root Necrosis of Peanuts Caused By a Species of Calonectria , 1966 .