Aida T.S. Matsumura, Ariano M. Prestes, Sueli T. Van Der Sand, Andréia M.R. de Oliveira
Published: December 30, 2002
Genet. Mol. Res. 1 (4) : 350-358

Cite this Article:
A.T.S. Matsumura, A.M. Prestes, S.T. Van Der Sand, A.M.R. de Oliveira (2002). Intraspecific variability of Bipolaris sorokiniana isolates determined by random-amplified polymorphic DNA (RAPD). Genet. Mol. Res. 1(4): 350-358.

About the Authors
Aida T.S. Matsumura, Ariano M. Prestes, Sueli T. Van Der Sand, Andréia M.R. de Oliveira

Corresponding Author
Andréia M.R. de Oliveira
Email: andreia-oliveria@fepagro.rs.gov.br

ABSTRACT

Isolates of Bipolaris sorokiniana were analyzed by random-amplified polymorphic DNA (RAPD) techniques to determine the amount of intraspecific genetic variability and to study host-pathogen interactions. Ten isolates originated from different regions of Brazil were examined. Plants of the wheat cultivars BR8, BH1146 (original host) and IAC-5 Maringá, classified as resistant, moderately resistant or susceptible to B. sorokiniana, respectively, were inoculated with these 10 isolates. Twenty-seven isolates were recovered from these cultivars and were analyzed by RAPD assay and compared to the RAPD of the original 10 isolates. According to the RAPD profiles there was a high level of genetic variability among the isolates. We detected 69 polymorphic fragments, ranging from 1.6 to 0.54 kb, in the original 10 isolates; 57 fragments with sizes between 1.98 and 0.38 kb from the isolates recovered from BH1146; 47 polymorphic bands, ranging from 1.96-0.54 kb, were detected in the isolates from BR8 and 32 fragments between 1.98 and 0.42 kb in isolates were recovered from IAC-5 Maringá. The number of polymorphic fragments varied, even for the same isolate, when the isolates were recovered from different cultivar hosts.

Key words: Genetic variability, Bipolaris sorokiniana, Wheat, RAPD.