National Center of Excellence in Molecular Biology (CEMB)
Abstract
Background: Barley yellow dwarf in wheat is an important viral disease among wheat cultivating areas of the world. It is gradually progressing as a major threat to wheat crop in Pakistan due to availability of favorable environmental conditions. The use of resistant cultivar is environmentally safest method for disease control so, it is necessary to develop resistant cultivars before epidemic outbreaks.Methods: The most commonly used wheat variety Inqilab91 was crossed with BYDV / CYDVresistant variety TC14. F1 generation obtained from the P1 cross was then allowed to self-cross. 61 plants were selected from F2 generation onTHE BASIS OF disease tolerance or susceptibility and only tolerant plants were included for further experiments in the study. The presence of BDV2 among F2 generation was confirmed by sequence characterized amplified region (SCAR) markers in 6 (91, 96, 110, 119, 121 and 131) out of 61 genotypes which were then backcrossed with recurrent parent. Advance analysis regarding the presence of resistance source among the selected F2 generation was carried out using ELISA. Moreover, appearance of symptoms, agronomic values for different parameters, green house and field responses were also kept under consideration to characterize and confirm the presence of BDV2 among plants.Results: Results indicated that majority of F2 segregating population showed less yellowing, low viral titer and good agronomic values. ELISA value, glasshouse and field analysis showed that seven genotypes (30, 81, 89, 91,101,110 and 121) were resistant, and twenty-four genotypes were found moderately resistant. Tolerance was detected in genotypes 31, 47, 48, 50, 52, 56, 57, 60, 61, 94, 103, 106, 113, 115, 127, 140 and 413.Conclusion: Wheat lines containing Bdv2 genes showed resistance in both field and glasshouse. These wheat germplasm could be used as a source of resistance in CDRP-NARC for the further development of resistant wheat varieties against BYDV / CYDV
