التنوع الوراثي بين عزلات لبعض الفطور الممرضة للحشرات المعزولة من مناطق مختلفة

الملخص EN

Assessment of the genetic variability of entomopathogenic fungi (EPF) is useful for the development of effective biocontrol strategies.

In this study, 24 isolates, derived from three species of EPF were collected from different geographical regions, approximately half of them from Syria.

Initially, the DNA was extracted from the fresh mycelium following CTAB procedures.

DNA concentration and purity were tested using the UV absorbance values at 260 and 280 nm.

Furthermore, the integrity of the extracted DNA was tested in 1% agarose gel.

Twenty four RAPD primers were applied for studying the genetic diversity.

High DNA concentrations were extracted (3.2 μg/μl from B.

bassiana, and 2.9 μg/μl from I.

farinosa and L.

lecanii) with UV 260/280 absorbency ratio of 1.7 for all tested isolates.

Four RAPD primers revealed polymorphism and separated the isolates according to the fungus species into two main clusters.

The first cluster included Isaria isolates and the second one contained two groups, one for Beauveria and the second for Lecanicillium.

Banding pattern of P793 marker showed high efficiency in distinguishing the fungi species in contrast to other markers.

Genetic diversity was not associated with geographic location.

RAPD analysis revealed the presence of high level of genetic diversity between the tested isolates.

The sets of amplified bands showing identical pattern to others were grouped at 100% similarity level.

A wide range (6 -100%, 18–86% and 17-56%) of Jaccard similarity coefficient was observed among the isolates of B.

bassiana, I.

farinosa and L.

lecanii, respectively.