Race 2 anthracnose disease rating data for genetic study in three watermelon populations: population 1 (PI 189225 x New Hampshire Midget), population 2 (Perola x PI 189225), and population 3 (Verona x PI 189225).
Steps to reproduce
F2 individuals were generated by selfing F1 individuals obtained from the crosses of Population 1 (PI 189225 x ‘New Hampshire Midget’), Population 2 (‘Perola’ x PI 189225), and Population 3 (‘Verona’ x PI 189225). PI 189225 is resistant to race 2 anthracnose. The race 2 anthracnose isolate was used to inoculate the three-week old watermelon seedlings. The watermelon seedlings were inoculated with a 100,000 spores/mL concentration of the fungus in a greenhouse using a CO2 sprayer at 30 PSI. Inoculated seedlings were moved into a humidity chamber (approximately 100% relative humidity, temperature: 22 to 24 °C) for 48 hours and later placed under natural light at greenhouse (day temperature: 30 °C and night temperature: 25 °C). The biparental F2 populations were rated at seven days post inoculation. True leaves from each watermelon seedling were rated for percent leaf lesion, 0% indicating no lesion and 100% indicating dead true leaf.