Concurrent improvement of durum and emmer wheat through reciprocal backcrossing and hybridization

Emmer wheat has not been improved but is a valuable gene source for improving durum (Triticum turgidum ssp. durum). Conversely, durum is less looked upon for emmer (T. turgidum ssp. dicoccum) improvement. This study examined the possibility of concurrently improving the two species by crossing eight durum cultivars with four emmer local varieties in a half-diallel fashion in two consecutive years. Also, emmer and two durum genotypes were reciprocally backcrossed, and their BC1F1 progeny were field-evaluated during the wheat cropping season (November-June) at the Isfahan University of Technology research farm (32 degrees 32 ' N, 51 degrees 23 ' E). The results showed that durum wheat had a considerable effect on the grain yield (GY), kernel diameter, 1,000-kernel weight (TKW), and test weight of F-1 hybrids, whereas emmer contributed more to increasing the grain protein content (GPC), kernel length, and plant height (PH). A similar pattern was observed for BC1F1 hybrids from the two recurrent durum parents. The GPC was reduced with recurrent durum parents in the backcrosses compared with emmer, but was still higher than in both durum parents. In the backcrosses with the recurrent emmer parent, GY and TKW were higher than those of emmer but only slightly lower than those of the durum parents. The PH was strongly influenced by emmer in all crosses, though the lodging was significantly reduced compared with emmer, possibly through obtaining stronger stems from durum. These findings suggest the possibility of combining desirable genes from the two species and their concurrent improvement in a single breeding program.