2.1 │ Plant material
Two cucumber genotypes to damping-off (Soheil and Ramezz), one
moderately resistant genotype (Baby) and three susceptible genotypes
(Extrem, Mini 6-23 and Yalda) were selected among a collection of
thirty-eight commercial genotypes of domestic and exotic hybrids, and
inbred lines from different seed companies, we recently investigated and
were screened in another study to identify resistant and susceptible
genotypes (Hashemi et al., 2019, Nasr Esfahani 2019). The six genotypes
are listed from least to most susceptible according to the disease
severity index in greenhouse investigations in Table 1. A number of 100
seeds per genotypes were grown in seedling nursery trays filled with
forced-air oven sterilized mix of sand-peat moss in equal parts at 200°F
for 30 minutes. Cucumber seedlings were grown in a greenhouse condition
(26±2°C), provided with 16 h photoperiod and 65% relative humidity. The
experiment was arranged in a completely randomized factorial design with
three replications (Nasr Esfahani 2012, 2014).