Pathogenic Variability and Differential Interaction of Blast Fungus (Pyricularia grisea SACC.) Isolates with Finger Millet Lines in Nepal

To understand the pathogenic variability of Nepalese isolates of Pyricularia grisea pathogenic to finger millet and their differential interaction with this millet exotic lines and landraces, an experiment was conducted at Institute of Agriculture and Animal Sciences (IAAS), Rampur, Chitwan during August to October, 2008. Five Pyricularia isolates collected from Lumle, Pokhara, Gulmi, Kabre and Rampur were tested with five landraces Acc#4337, Acc#6202, Acc#456, KLB#184, Kabre and four exotic lines, PR#202, HR#911, SPFM#K2, and GPU#48 which have been used in national finger millet research programme by Hill Crop Research Programme (HCRP), Kabre, Dolakha. The experiment was laid out in 5x 9 factorial completely randomized designs with 4 replications in screen house. Eighteen-day-old seedlings grown in earthen pots were inoculated with a Pyricularia spore suspension (105ml-1) with the hand sprayer. Disease assessment was done in five days after inoculation. The aggressiveness of the isolates was noticed maximum in Pokhara and minimum in Gulmi isolates. Considerable pathogenic variations among the tested isolates were observed, however, no clear cut differential interactions were noticed in the interaction. The exotic lines showed comparatively resistant against the fungus reaction than the landraces. Among the tested lines Gpu#48, showed resistant reaction and Acc#4337 showed susceptible reaction in artificial inoculation. DOI: http://dx.doi.org/10.3126/njst.v14i2.10411 Nepal Journal of Science and Technology Vol. 14, No. 2 (2013) 17-24