RFLP-ITS-rDNA profiles of four populations of Heterodera cruciferae collected from Tabriz vegetables growing area against restriction enzymes. A: K6, B: K3, C: C6 and D: C3 (1: Ladder, 2: Intact PCR product, 3: Mva I, 4: Alu I, 5: Xba I, 6: Pst I, 7: Bsu R I, 8: Pvu I, 9: Sa II, 10: Hinf I, 11: Hin 6 I, 12: Eco RI, 13: Rsa I, 14: Bam H I, 15: Bsp 143 I, 16: Hind III, 17: Kpn I, 18: Msp I, 19: Ladder).