| Popis: |
Control of virus diseases such as zuchini yellow mosaic virus (ZYMV) of cucumber causing major yield and quality losses is impossible by using any chemical pesticide except for using elimination of vectors of viruses and resistant cultivar. The objectives of this study were to investigate structure of genetic resistance to ZYMV of cucumber for marker-assisted selection (MAS). Forty-eigth resistant and 48 susceptible lines were selected from a germplasm of 600 cucumber lines. Bulk DNAs of resistant and susceptible lines were screened to find candidate marker(s) by using ISSR, RAPD and a cleaved amplified polymorphism (CAP) primers, which targeted over 5000 loci of cucumber. Candidate markers later were applied to 96 lines including 48 resistance and susceptible lines to find associating markers. A total of 54 candidate marker loci were produced, which were clustered into two groups based on Dice’, average distance, simple matching and correlation similarity matrices. In the association analyses by using TASSEL software, associating markers were detected. These markers were then subjected to backward regression analysis by SAS program. The results explained %78 of total variation for ZYMV. The remaining 22% of the variation was possibly due to presence of additional gene(s) and environmental effect that caused lower repeatability. |
