Centre : Indian Institute of Vegetable Research
Name of the Protocol
Molecular race identification of Fusarium oxysporum f.sp. lycopersici infecting tomato in India
Nature : Modification of existing protocol
Crop / Pathogen : Tomato/Fusarium oxysporum f.sp. lycopersici
Twenty isolates of Fusarium oxysporum f.sp. lycopersici infecting tomato collected throughout India was subjected to PCR reaction for the detection of races prevalent in India. Two set of specific primers based on polygalacturonase gene that can amplify race 1 & 2 and race 2 & 3 were used. PCR reactions were carried out in a 25µl volume consisting of 1X PCR buffer (Fermentas Inc., USA), 0.2mM of each dNTPs (Fermentas Inc. Maryland, USA), 2mM MgCl2 (Fermentas Inc. Maryland, USA), 0.5µM of each primers (Eurofins), 1U of Taq DNA polymerase (Genei, Banagalore), 2.5µl of template DNA and final volume make up with sterile distilled water. The thermal cycling conditions used were: initial denaturation at 94°C for 5min, followed by 45 cycles of denaturation, annealing and elongation steps respectively at 94°C for 60sec , 61ºC for 60sec and 72ºC for 2min and a final extension step of 72ºC for 10min. Race 1 of FOL was found to be prevalent in India. This race identification has been confirmed with the differential varieties obtained from the AVRDC specific to different races by inoculating the 21 days old tomato plant with conidial suspension by root dipping and planting in sterilized soil under green house conditions.