The Fusarium genus is responsible for serious diseases in many economically important crops. Among these diseases it is distinguished the mango flower malformation, caused by the fungus Fusarium subglutinans. The objective of this work was to develop specific oligonucleotide primers for the polymerase chain reaction (PCR) targeting the mango flower malformation by fungus F. subglutinans. The DNA amplification of eight Fusarium spp. collected from different hosts making the use of a random oligonucleotide primer UBC-41 generated a fragment of approximately 1300 pb in size, specifically for the mango flower malformation fungus (Fusarium subglutinans). Since standard RAPD banding patterns are not considered reliable because of their low results of reproducibility, the distinctive fragment was eluted off the agarose gel, purified, cloned and then sequenced. The nucleotide sequences were used to identify and also to synthesize four pairs of specific oligonucleotide named herein Fs 5, Fs 13, Fs 14 and Fs 15. Other Fusarium spp. DNAs sampled from other hosts (garlic, peanut, sugarcane, cyclamen, pea, melon and wheat), from a healthy mango tree cv. Tommy Atkins and other six isolates from symptomatic mango plants were submitted to PCR amplification with these pairs of oligonucleotide. Only fragments from the mango tree fungus Fusarium subglutinans were visualized, showing this way the SCAR oligonucleotide specificity.
primers; Mangifera indica; molecular markers; RAPD-PCR
