T. Prameela Devi1, Deeba Kamil1, Ravi Mehndiratta2, N. Prabhakaranand R. Sudeep Toppo1

1Division of Plant Pathology, Indian Agricultural Research Institute, New Delhi-110 012, India.
2Amity Institute of Biotechnology, Amity University Haryana, Amity Education Valley, Gurgaon-122413, Haryana, India.

Received on 16 July 2016 and accepted on 20 September 2016


Rhizoctonia bataticola (Taub.)Butl.a omnipresent soil-borne fungus having pycnidial state as Macrophomina phaseolina (Tassi.) Goid., causes dry root rot disease in a wide range of hosts starting from cereal crops to horticultural and medicinal crops. The present study was aimed to find out genetic and morphological variability among the twenty five indigenous isolates of R. bataticolacollected from geographically distinct regions (10 states) infecting 19 different crop plants. Sclerotial morphology of the isolates was studied and they were confirmed to species using species-specific primers. All the isolates were grouped into four different types of sclerotia. Genetic diversity of all these isolates was analysed using random amplified polymorphic DNA (RAPD) markers and inter simple sequence repeat (ISSR) markers. Ten random primers for RAPD and six primers for ISSR were tested for amplification of genomic DNA of R. bataticola isolates. Best six primers for RAPD and five primers for ISSR were further analysed. Unweighted pair-group method using arithmetic means (UPGMA) clustering of data showed that isolates did clearly differentiate to the specific group according to the geographical origins. ISSR markers were found more efficient than RAPD markers to correlate the genetic diversity with the grouping of isolates according to the geographical regions.But RAPD markers were found efficient todifferentiate R. bataticola isolates into different clusters according to their sclerotial morphology. It was the first study that investigated genetic relationships with two PCR-markers among different isolates of R. bataticola belongs to different hosts from India.

Keywords: Dry root rot, Genetic diversity, ISSR, Rhizoctonia bataticola, RAPD, Sclerotial morphology.