Assessment of seed germination on the response to water potential in different canola genotypes using hydrotime model

Identification of cultivars with tolerance to water stress has important for crop production in arid and semi-arid areas. In order to, a factorial experiment was conducted based on completely randomized design with two factors of 20 genotypes of canola and 5 water potentials of 0, -0.15, -0.3, -0.5, and -0.8 MPa in 4 replications in Seed Technology laboratory of College of Aburaihan, during 2015-16. Seed germination of different genotypes was recorded twice in a day for each water potential at 20 oC. Thereafter, Hydrotime model was fitted to time course germination. Results indicated that Karaj1 and Opera had the lowest value of base water potential with -1.23 and -1.2 (MPa) and they were the most tolerant genotypes to drought. Genotypes of 203 and Likord had the highest value of base water potential with -0.27 and -0.22 and the most sensitive genotypes to water stress. The lowest hydrotime constant belonged to Zarfam and Talaye with 22.67 and 23.73 MPa-hours and the highest hydrotime constant belonged to 389 and Opera with 50.93 and 48.07 MPa-hours. The base water potential with 95 % had the highest broad sense heritability. Using this information it is possible to identifying genotypes with higher efficiency and more tolerate to water stress in future breeding programs to breed new genotypes with tolerance to water stress.