Evaluation of quantitative and qualitative characteristics of promising bread wheat lines of hot and dry southern climate in the farmers conditions of Khozestan Province

Introduction: Investigating new wheat lines in the form of advanced experiments in similar climate regions and using their classification in order to obtain suitable cultivars for cultivation in each region is common in most of the world's breeding programs. The superior lines of these tests need to be tested in farmers' field conditions for further investigation. Therefore, the selected lines along with the common cultivars of the region are evaluated in the performance comparison test under the title of research-promotional tests. Considering the fact that the environmental conditions can play a significant role in the agronomic and baking characteristics of wheat, this research aims to investigate the quantitative and qualitative characteristics of promising bread wheat lines in hot and dry regions of the country and to identify superior lines for introduction of new variety, was implemented in the conditions of farmers in the northern region of Khuzestan province.
Materials and methods: This experiment was carried out during two crop years of 2021-2023 in the fields of farmers in Shush and Dezful regions in the north of Khuzestan province and in 2000 meter plots. In the first year, four promising lines were evaluated along with the Mehregan variety, and in the second year, three other promising lines were evaluated along with the Mehregan control. The agricultural traits measured included yield and yield components and plant logging. In addition, in order to determine the quality and bakery characteristics of the tested lines, a mixed sample from two regions was prepared and evaluated every year.
Results: The results related to the measured agronomic traits of the promising bread wheat lines of the ER97 series in the first year of the experiment with Mehrgan showed that the performance of these lines has increased significantly compared to the tested line, so that in the Dezful region, line S-10-97 with a yield of 7042 kg/ha has a 28% increase in yield compared to the control variety (with a yield of 5515 kg/ha). On the other hand, the same line has shown an increase of 17% compared to the control with a yield of 6124 kg per hectare in Shush region. Also, the evaluated promising lines are superior to the control variety in terms of other agricultural traits measured. In addition, the results related to the measured agricultural traits of the promising bread wheat lines of the ER98 series in the second year of the experiment with Mehrgan showed that in Dezful region, the yield of S-98-22 line increased by 17% compared to tested line from 4833 kg per hectare to 5660 kg per hectare. The yield of this line in Shush has increased by 14% compared to Mehregan from 4374 kg/ha to 4970 kg/ha. Also, the results related to quality and bakery traits showed that the promising lines of bread wheat compared to the Mehrgan control have an acceptable superiority in most of the measured traits, so that the percentage of grain protein in these lines in the first year compared to the Mehregan (12.7 percent), increased and reached 13 percent in S-97-2 line. Also, in the second year of the experiment, the protein percentage increased from 12.5% in the control to 12.8% in the S-98-11 line.
Conclusion: In general and considering that the studied lines were acceptable and higher than Mehregan's control in terms of quality and bakery parameters, the final selection was made based on crop traits related to yield. Therefore, in the first year, the S-97-10 line with an average yield of 6583 kg per hectare and a 22% increase compared to the control was selected as a candidate line for introduction. Also, based on the results of the second year, the S-98-22 line with an average yield of 5315 kg per hectare in Shush and Dezful regions and an increase of more than 15% compared to Mehregan (control line) as the superior line to be introduced as a new cultivar suitable for cultivation in hot and dry south of the country was chosen.