Selective Isolation and Characterization of Phytophthora infestans from Potatoes Using Rye Agar Media in India
Lingareddy Usha Rani
Department of Plant Pathology, Centre for Plant Protection Studies, Tamil Nadu Agricultural University, Coimbatore – 641003, India.
G. Senthilraja *
Department of Plant Pathology, Centre for Plant Protection Studies, Tamil Nadu Agricultural University, Coimbatore – 641003, India.
P. Parameshwari
Department of Plant Pathology, Centre for Plant Protection Studies, Tamil Nadu Agricultural University, Coimbatore – 641003, India.
V. Paranidharan
Department of Plant Pathology, Centre for Plant Protection Studies, Tamil Nadu Agricultural University, Coimbatore – 641003, India.
D. Jeya Sundara Sharmila
Centre for Agricultural Nanotechnology, Tamil Nadu Agricultural University, Coimbatore – 641003, India.
M. Raveendran
Department of Plant Biotechnology, Centre of Plant Molecular Biology and Biotechnology, Tamil Nadu, Agricultural University, Coimbatore – 641003, India.
Sanjeev Sharma
ICAR-Central Potato Research Institute, Shimla - 171 001, India.
Priyank Hanuman Mhatre
ICAR-Central Potato Research Institute Regional Station, Ooty - 643 004, India.
*Author to whom correspondence should be addressed.
Abstract
Phytophthora infestans is a pathogen that causes late blight, a major disease of potatoes. The isolation of P. infestans from infected potato plants using agar media has been challenging. This study investigated the use of Rye A and Rye B agar media for the isolation of P. infestans from infected potato tubers collected from the Nilgiris district of Tamil Nadu during 2022. The media were evaluated for hyphal growth, sporangial production, oospore formation, and long-term storage of P. infestans. Phenotypic diagnosis based on cultural and morphological characteristics confirmed the identity of P. infestans. The results were confirmed by a molecular identification test using primers specific to P. infestans. Pathogenicity tests were carried out to assess the virulence of the isolates. This study provides a useful protocol for the selective isolation and characterization of P. infestans, the potato late blight pathogen.
Keywords: Phytophthora infestans, late blight disease, rye agar, potato, isolation