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Background and objectives: Durum wheat (Triticum turgidum L. var. durum) is an industrial and agricultural product that is mainly used in pasta production industries. One of the important goals of durum wheat breeding programs is to produce high-yielding cultivars that have suitable characteristics for cultivation in different regions of the country. Therefore, the purpose of this research was to investigate the genotype × environment interaction using GGE biplot graphic method in durum wheat promising lines and to identify and introduce lines with economic and stable yield for introduction and cultivation in different regions of the country. Materials and methods: In this experiment, 18 promising lines of durum wheat with two check Hana and Aran in five research stations of Karaj, Kermanshah, Khorramabad, Dezful and Darab (under two conditions of normal irrigation and irrigation cutting during the flowering stage) were cultivated and compared in the form of randomized complete blocks design in three replications and in two cropping seasons (2019-2021). Results: The results of two-year combined variance analysis for grain yield under normal irrigation conditions in five research stations of Darab, Dezful, Khorramabad, Karaj and Kermanshah and dry conditions at the end of the season in Darab showed that the effect of year in both conditions and all stations was significant. In normal irrigation conditions, the difference between genotypes grain yield was significant in Darab, Dezful and Kermanshah stations, but not significant in Karaj and Khorramabad stations. Genotype × year interaction was significant under normal conditions in Darab and Kermanshah, but not significant in Karaj, Dezful and Khorramabad. Based on the average grain yield, lines G8, G9, G10, G14 and G18 (respectively with the average grain yield of 7725, 7597, 7742, 7661 and 7558 Kg ha-1) were superior to the controls. According to the GGE biplot, three large environments were identified. The first large environment included Dezful and Khorramabad regions, and G8 and G10 genotypes were among the top genotypes in these two regions, respectively. The second largest environment was Kermanshah and Karaj, and G9 and G14 genotypes were among the top genotypes in these two regions. The third large environment included two test conditions in Darab and the superior genotype in Darab was G18 in both drought stress and non-stress conditions. GGE Biplot results showed that G8 and G10 genotypes were among the most stable lines and also had the highest grain yield. The comparison of the studied lines with the ideal genotype showed that G10 and G8 are the closest genotypes to the ideal genotype, which have the highest grain yield and stability. The results of qualitative characteristics showed that the hardness index average of genotypes was in the range of 57-58% and the promising lines were not significantly different from the control cultivars. G17 genotype had the lowest (14%) and G14 genotype had the highest average of grain yellow berry (45%). Also, a relatively large variation was observed in terms of the amount of wet gluten, so that genotypes G9 and G13 had the lowest and highest amount of wet gluten with 23.8 and 27.3%, respectively. Conclusion: In general, according to the average grain yield and GGE biplot results in both normal and drought conditions and according to some quality characteristics of the grain, lines G8 (D-98-8) and G10 (D-98-10) were selected as the most suitable lines for both normal and dry conditions. These lines will be tested in on-farm yield trials of next crop season and finally one of them will be introduced as a new cultivar. [ABSTRACT FROM AUTHOR]

Background and objectives: Drought stress is the most important abiotic stress limiting growth and development of crops. Zinc is one of the required elements for chemical processes in the plants. Studies have shown that the application of zinc fertilizer reduces the negative effects of drought stress leads to an increase in yield and yield components of crops. Therefore, this study was conducted in order to evaluate the effect of application of different forms and concentrations of zinc fertilizer on the yield and oil quality of Neptune variety rapeseed oil under water stress conditions during the 2019 and 2020 in Biston region located in Kermanshah province. Materials and methods: The experiment was carried out in a splitplot design based on a randomized complete block design with four replications. Water stress treatment as the main factor (no stress, cut of irrigation at early flowering and cut of irrigation at early podding), foliar treatment as a secondary factor at two levels (s zinc sulfate and zinc nanochelate) with three concentrations of zero, 3 and 5 per thousand. Results: The results showed that the effect of drought stress and application of zinc sulfate on the characteristics of seed yield, biological yield, seed oil percentage, seed oil yield, erucic acid percentage and oleic acid percentage were significant. Also, according to the results of mean comparison, it was found that increasing the zinc sulfate concentration and nano zinc application increased the grain yield and biomass up to 2839 Kg ha-1 and 14634 Kg ha-1, respectively. The effect of zinc nanochelate on the increase of these two traits was greater than that of zinc sulfate. Oil percentage and yield decreased in both levels of water stress. According to the results, it was found that increasing of Zn concentration especially the nano form increased oil percentage up to 43.6% and its yield up to 1423 Kg ha-1. In addition, it was found that water stress reduced the percentage of oleic acid in rapeseed oil, but nanozinc partially compensated for this decrease and increased the percentage of oleic acid to 65.75%. Conclusion: According to these results, it was found that although the percentage of oleic acid decreased with the cut of irrigation during the flowering and podding stages, the results showed that the application of zinc nanochelate in the conditions of drought stress and the absence of drought stress had a more positive effect on increasing the percentage of oil oleic acid. Therefore, the application of nano zinc chelate can be suggested in the conditions of drought stress to increase the yield and quality of rapeseed oil in the region. As a result, in order to achieve the maximum seed yield and high oil quality in rapeseed, a concentration of 5 per thousand zinc nanochelates can be used in the absence of drought stress. [ABSTRACT FROM AUTHOR]