3.1 │ Disease response
P. melonis -inoculated plants of all tested genotypes revealed a wide range of symptoms depending on their genetic makeup and none of the inoculated plant was symptomless. The genotypes responded as resistant showed minor symptoms, moderately resistant ones indicated moderate, while highly susceptible genotypes revealed severe symptoms as earlier reported by hashemi et al. (2019). The defense response in the resistant genotypes were able to stop pathogen growth and infection, whereas in the susceptible genotypes, necrosis continued to progress along the roots and stem until the plant dies (Fig 1).