Abstract
To produce salt-tolerant wheat germplasm through wide hybridization, 8 different salt-tolerant accessions of Ae. cylindrica were crossed with 3 hexaploid wheat cultivars: Pak-81, LU-26, and Shalimar-88. Frequency of seed set ranged between 1.72% (Shalimar-88 x Ae. cylindrica acc. 38-53) and 52.6% (Pak-81 x Ae. cylindrica acc. G.). The performance of wheat cultivars LU-26 and Shalimar-88 as female parent for F hybrid production was poor. Frequency of BC1 seed production ranged between 0.53% (Pak-81 x Ae. cylindrica// LU-26) and 8.92% (Shalimar-88 x Ae. cylindrica// LU-26). BC1 plants with different chromosome numbers were selfed to produce BC1F1 derivatives. Seven BC1 combinations produced selfed seeds ranging between 1 and 200. Six BC1 combinations did not produce selfed seeds and were backcrossed again with LU-26 to produce BC2 seeds, which ranged between 1 and 12 seeds per BC1 combination. Of the 30 different BC2 seeds produced in different combinations, only 19 produced BC2F1 selfed seeds. All the BC2F1 and BC1F2 seeds were tested for germination under saline solutions of EC 2.5 (control) 15, 20, and 25 dS/m. Salinity induced reduction and delay in seed germination; reduction in shoot and root length and in seedling fresh weight was observed with considerable variation among different salinity levels and among different genotypes at one salinity level. The results have been discussed with reference to the wide hybridization approach and its potential use in the production of genetic variability for polygenically controlled characters such as salt-tolerance.