This article discusses the isolation and characterization of PR1 gene in Grand Naine during the time of infection by Meloidogyne incognita. The methodology includes the use of RNAiso Reagent Kit, PCR Fragment Recovery Kit, PCR cloning vector pmem, restriction enzymes, and other chemical reagents. The article also covers the treatment of the culture, isolation of total RNA and DNA, cloning of PR1 gene and full cDNA, Southern blotting, and expression of PR1 in Grand Naine.