Article

Viral coat protein gene was detected in thirty isolates of different soil-borne fungi, using cotton leaf curl coat protein specific primers (geminiviruses). Out of them, seven fungal isolates showed positive results (a band with a molecular size of 680 bp). The products amplified from two isolates, Macrophomina phaseolina (Tassi) Goid. and Mucor racemosus Bull., were excised from the gel, purified and sequenced. The sequence analysis revealed that the amplicons were coat protein genes of geminivirus. The gene isolated from M. phaseolina was similar to that of wheat dwarf geminivirus with identity not exceeding 36 %; and the coat protein isolated from M. racemosus was 43 % identical with the maize streak geminivirus. These low identities suggest that the amplification products belong to new records of geminiviruses designated (MpDV) and (MrDV), respectively. The isolate from M. racemosus was selected to investigate the viral transmission into the phytopathogenic fungus Fusarium oxysporum Schlecht. Some phenotypic changes were observed in the infected mycelia of F. oxysporum, including growth rate reduction and increased pigmentation. The infected mycelia of both fungi were subjected to electron microscopy examination and the results revealed that different virus-like particles (VLPs) were observed. This finding may help in understanding and using the ssDNA mycoviruses in fungal biocontrol and expands our knowledge of virus ecology and evolution.