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Antagonistic
activity of selected strains of Bacillus thuringiensis
against Rhizoctonia solani of chili pepper
Virgilio Mojica-Marín1*,
Hugo A. Luna-Olvera2, Carlos Fco.
Sandoval-Coronado2, Benito Pereyra-Alférez2,
Lilia H. Morales-Ramos2, Carlos E. Hernández-Luna2
and Omar G. Alvarado-Gomez3.
1Facultad de Ciencias
Químicas. Universidad Juárez Del Estado de Durango (UJED),
Av. Veterinaria s/n, Circuito Universitario, CP. 34120.
Durango, Dgo. México.
2Facultad de Ciencias
Biológicas. Universidad Autónoma De Nuevo León (UANL), Av.
Pedro de Alba y Manuel L. Barragán, Ciudad Universitaria,
CP. 66450, A.P. 414 y 2790 San Nicolás de los Garza, Nuevo
León, México.
3Facultad de Agronomía.
Universidad Autónoma De Nuevo León (UANL), Carretera Zuazua
-Marín Km 17.5, CP. 66700. Marín, Nuevo León, México.
*Corresponding author. E-mail:
vmojica@citologica.com,
vmojicamx@yahoo.com.mx. Tel/Fax: (618) 1-30-11-11;
1-30-11-20.
Accepted 12 March, 2008 |
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The aim of this work was to determine, in vitro, the
antagonistic effectiveness of 60 strains of Bacillus
thuringiensis against damping-off and root and stem rot
caused by Rhizoctonia solani. The strains were
obtained from the International Collection of
Entomopathogenic Bacillus at the FCB-UANL. During the in
vitro dual culture assay only 16 of the strains
displayed an inhibitory effect. Six strains were chosen to
be screened simultaneously by volatile antibiotics,
thermostability and seedling assay. In the volatile
antibiotics assay, the strains GM-11 and GM-121 showed the
best inhibitory effect over R. solani growth. None of
the strains showed an efficient antagonistic effect during
the thermoestability assay. In seedling assay, majority of
the antagonistic isolates, GM-23, GM-11and GM-121, were
effective in the reduction of R. solani infection. In
addition, GM-23 increased the length of pepper seedlings.
These results suggest that the B. thuringiensis
strains studied have an excellent potential to be used as
bio-control agents of R. solani in chili pepper.
Key words:
Antagonist, biological control, damping-off, Rhizoctonia
solani. |
