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 BC 1 F 1 progeny were field-evaluated during the wheat cropping season (November-June) at the Isfahan University of Technology research farm (32˚32′ N, 51˚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 BC 1 F 1 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.

Few prior efforts have been made to investigate the genetic potential of different subspecies of Triticum turgidum for drought tolerance and their quality-related traits compared with common wheat (Triticum aestivum) and to identify the association among agronomic, micronutrients, and quality-related traits, especially under climate change conditions. In this research, grain quality, technological properties of flour, and some agronomic traits were studied in 33 wheat genotypes from six different subspecies of Triticum turgidum along with three cultivars of Triticum aestivum in the field, applying a well-watering (WW) and a water stress (WS) environment during two growing seasons. A high degree of variation was observed among genotypes for all evaluated traits, demonstrating that selection for these traits would be successful. Consequences of water stress were manifested as declined DM, GY, and LASRC; and significantly increased GPC, K+/Na+, WAF, WSRC, SuSRC, and SCSRC compared to the well-watering condition. The reductions in the unextractable polymeric protein fraction and glutenin-to-gliadin ratio indicated a poorer grain yield quality, despite higher protein content. This study showed that the early-maturing genotypes had higher water absorption and pentosan, and therefore were more suitable for bread baking. In contrast, late-maturing genotypes are ideal for cookie and cracker production. Two subspecies of T. turgidum ssp. durum and T. turgidum ssp. dicoccum with high micronutrient densities and quality-related traits, and T. turgidum ssp. oriental due to having high values of grain protein content can be used to improve the quality of T. aestivum through cross-breeding programs. Based on the association of different traits with SRC values and other quality-related traits and PCA results, contrasting genotypes can be used to develop mapping populations for genome studies of grain quality and functional properties of flour in future studies.

This study aimed to examine the reaction of several wheat species with different ploidy levels to foliar application of zinc (Zn) and iron (Fe) under different water regimes. Thirty-five wheat genotypes, including nineteen tetraploids from ten different species, ten hexaploids from five species, and six diploids from three species, were evaluated in the field over two moisture regimes with the following four treatments: control, foliar Zn application, foliar Fe application, and foliar Zn + Fe application. The experiments were conducted according to a split-plot scheme in a randomized complete block design with two replications in each moisture regime. Water stress negatively affected all measured traits, except grain Zn and Fe content. Combined foliar application of Zn + Fe significantly increased yield and alleviated yield reduction caused by water stress. Applying Zn and Fe significantly increased both micronutrient content in grains under both moisture conditions. Tetra and hexaploid species yielded nearly four times as much grain as unimproved diploid species and were less affected by water stress. All ploidy levels responded almost similarly to Zn and Fe treatments, with the combined application being as effective as each element separately. The highest yield increase in response to combined application of Zn + Fe under the two moisture conditions and the highest grain Zn content in response to Zn application under water stress was observed in hexaploid wheat. Combined foliar application of Zn and Fe increases grain Zn and Fe and alleviates water stress's adverse effects on all wheat ploidy levels, making biofortification cost-effective.

Few prior efforts have been made to investigate the genetic potential of different subspecies of Triticum turgidum for drought tolerance and their quality-related traits compared with common wheat (Triticum aestivum) and to identify the association among agronomic, micronutrients, and quality-related traits, especially under climate change conditions. In this research, grain quality, technological properties of flour, and some agronomic traits were studied in 33 wheat genotypes from six different subspecies of Triticum turgidum along with three cultivars of Triticum aestivum in the field, applying a well-watering (WW) and a water stress (WS) environment during two growing seasons. A high degree of variation was observed among genotypes for all evaluated traits, demonstrating that selection for these traits would be successful. Consequences of water stress were manifested as declined DM, TGW, GY, and LASRC; and significantly increased GPC, ZEL, GH, WAF, WSRC, SuSRC, and SCSRC compared to the well-watering condition. The reductions in the unextractable polymeric protein fraction and glutenin-to-gliadin ratio indicated a poorer grain yield quality, despite higher protein content. This study showed that the early-maturing genotypes had higher water absorption and pentosan, and therefore are more suitable for bread baking. In contrast, late-maturing genotypes are ideal for cookie and cracker production. Two subspecies of T. turgidum ssp. durum and T. turgidum ssp. dicoccum with high micronutrient densities and quality-related traits, and T. turgidum ssp. oriental due to having high values of grain protein content can be used to improve the quality of T. aestivum through cross-breeding programs. Based on the association of different traits with SRC values and other quality-related traits and PCA results, contrasting genotypes can be used to develop mapping populations for genome studies of grain quality and functional properties of flour in future studies.

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