Molecular Analysis of Genetic Variability  in Rhizoctonia solani AG–7 Isolates  Affecting Cotton Crop (Gossypium  hirustum) in Semi Arid Tropics

Manju Rani; J. S. Rana; K. K. Dahiya; Himansu Aggarwal; Namita Singh

Volume : II, Issue : III, March - 2013

Molecular Analysis of Genetic Variability in Rhizoctonia solani AG–7 Isolates Affecting Cotton Crop (Gossypium hirustum) in Semi Arid Tropics

Manju Rani, J. S. Rana, K. K. Dahiya, Himansu Aggarwal, Namita Singh

Abstract :

Rhizoctonia disease, caused by Rhizoctonia solani is one of the most important fungal diseases in cotton fields in Northern India. A total of 25 isolates of Rhizoctonia solani AG–7 obtained from diseased cotton seedlings showing typical symptoms of damping–off were characterized using universally primed PCR (UP–PCR) fingerprinting. Of 35 primers tested, two primers produced polymorphic amplification patterns with individual–specific bands. Amplification products obtained from the two UPs AA2M2 and L45 ranged between 0.3kb to 1.9kb. A combined dendrogram of 25 Rhizoctonia solani AG–7 isolates was prepared by using similarity coefficients of 30 DNA markers generated by UP primer AA2M2 and L45. At 0.27 similarity index the isolates divided into two groups. There was high genetic variability among the isolates collected from different locations. The results suggest that UP–PCR having long primer and higher annealing temperature, would be very useful, more sensitive and reliable marker in characterizing genetic diversity in R. solani.