Genetic Variations Among Isolates of <I> Trichoderma </I> from Rhizosphere of Chilli and Biofungicide
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Ninety-four isolates of Trichoderma spp. were randomly collected from the rhizosphere of chilli found in five different geographic regions. These isolates were isolated from the soil by using the dilution plate method. The other six isolates of Trichoderma spp. used in this study were from biofungicides. The results of their morphological studies indicated that 100 isolates of Trichoderma spp. could be grouped into seven species. The polymorphism of the internal transcribed spacer (ITS) regions was also used to characterize isolated Trichoderma spp. in this study. The ITS regions of 100 isolates of Trichoderma spp. were amplified by using a polymerase chain reaction (PCR) with universal primers ITS1 and ITS4. The amplified products (600 bp) were then digested with BamHI, SmaI and EcoRI. The BamHI digestion profiles could classify the 100 isolates of Trichoderma spp. into three groups. These results resembled the results of the cluster analysis of PCR-RFLP data which clearly partitioned the 100 studied isolates into three groups (at 78 percent similarity). Group A was comprised of T. harzianum 34 isolates, T. hamatum 23 isolates, T. aureoviride 14 isolates and T. viride 1 isolate, group B was comprised of T. koningii 4 isolates and group C was comprised of T. longibrachiatum 19 isolates and T. pseudokoningii 5 isolates.
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