To assess the response of promising safflower genotypes to late-season drought stress in delayed planting conditions, an experiment was conducted in two years (2016–2017 and 2017–2018) in Iran. The irrigation regime was specified in two levels, including normal irrigation and irrigation cut off in the seed filling stage in main plots, and five safflower genotypes, including Soffe, Goldasht, Golmehr, Padideh, and Parnian were categorized in subplots. Applied drought stress significantly reduced the seed yield and yield components of all genotypes, which accompanied with a substantial decrease in oil content and oil yield of all genotypes. However, the highest seed and oil yield in drought stress conditions obtained in the Parnian genotype by value 2338 and 561 kg/ha, respectively. Moreover, a significant drought-induced increase in palmitic, stearic, and oleic acids, as well as a decrease in linoleic acid content, was observed in all genotypes. Parnian genotype with high unsaturated fatty acids content (90.9%) and the minimum amount of saturated fatty acids (8.7%) might be a promising genotype to starting a formal crop improvement program to achieve more drought-tolerant safflower genotype.

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An experiment was performed in the Seed and Plant Improvement Institute, Karaj, Iran to study the influence of plant densities on physiological traits of six canola cultivars. Treatment conditions included three different plant densities (40, 60, and 80 plants m-2) for triplicates of six canola cultivars, namely, Ahamadi, Opera, Okapi, L72, Karaj1, and Sw102. Results indicated that L72 cultivar exhibited the highest yield at the lowest plant density (40 plants m-2). For all cultivars, both plant densities of 60 and 80 plants m-2 resulted in lower relative water content than 40 plants m-2. Proline and carbohydrate content significantly increased with increasing plant densities. The highest proline content was obtained from L72 under the highest plant density, whereas the lowest was also detected in this cultivar at the lowest plant density. All cultivars grown at the lowest density showed higher amounts of photosynthetic pigments chlorophylls a and b than those at the highest density. Glucosinolate increased with increasing plant densities, with L72 yielding the highest quantity when grown at the highest density. In conclusion, a density of 40 plants m-2 is recommended for growing L72 in this region.

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To assess the response of two safflower genotypes to auxin foliar application under late-season drought stress using a factorial split-plot experiment with the randomised complete block design, a two-year experiment (2016–2017 and 2017–2018) was conducted in Iran. The watering regime as specified in two levels including, regular irrigation and drought stress in main plots and two safflower genotypes and auxin foliar application in two levels including non-foliar application (control) and auxin foliar application at a concentration of 30 ppm were categorised in subplots. Drought stress at the seed filling stage reduced the safflower seed and oil yield. Moreover, a significant drought-induced decrease in linoleic acid, palmitic acid and behenic acid content, as well as an increase in oleic acids, was observed in two safflower genotypes. Among two safflower genotypes, the early maturing genotype less affected by drought and Goldasht had higher seed yield than the Padideh by 814 kg/ha, respectively. Auxin foliar application alleviates the adverse effects of drought, which led to an 18% increase in seed yield and components. However, the auxin application had no effect on the safflower seed oil content but palmitic acid content was affected by auxin foliar application. Generally, safflower along with auxin application can be recommended to develop safflower cultivation in semi-arid areas.

Multilayer composites have recently attracted considerable attention due to their ability to take advantage of the benefits of various metallic materials simultaneously. The present study is the first to use parallel tubular channel angular pressing (PTCAP) as a severe plastic deformation method to fabricate a bimetal Al/Mg tube. This process was applied on commercially pure aluminum along with an AM60 magnesium alloy at the temperature range of 250-400 °C. According to the microstructural and mechanical tests, there is a strong bond between layers besides the grain refinement after the process. Additionally, microhardness examinations showed that there is an excellent homogeneity in addition to the dramatic increase in the hardness of bimetallic PTCAP processed Al/Mg tube. Scanning electron microscope and energy-dispersive x-ray spectroscopy analyses in the interface between the layers and also the results of the shear strength test showed that by increasing the temperature, the diffusion rate at the interface increases. For instance, the significant bonding strength of 30 MPa was achieved after the PTCAP specimen at 400 °C. Therefore, these investigations substantiate that the PTCAP process can be used as an appropriate cladding technique for obtaining simultaneous severe plastic deformation microstructures and sufficient bonding strength in the production of bimetallic tubes.

To identify appropriate genotypes for breeding varieties suitable for semi-arid areas, yield components, as well as morphophonological traits of 127 safflower genotypes, were assessed at the Seed and Plant Improvement Institute, Iran. Cluster analysis revealed four distinct groups. The largest group (third cluster) includes 48 genotypes with characteristics such as mostly yellow-coloured flowers, mostly thorny with few thistle genotypes, relatively early-flowering, relatively high number of heads and grains per plant, highest 1000-grain weight with the highest grain yields. In contrast, the smallest group (second cluster) contains 13 genotypes with characteristics such as yellow florets, semi-dwarf, thorny, moderately late-flowering, low number of heads per plant and number of grains per head, low 1000-grain weight, and low grain yield. Principal component analysis results showed that the three components accounted for 29.5, 15.9 and 11.1% of the total variation, respectively. Graphic representation of the biplots based on the first and second principal components showed that the experimental genotypes were classified into four groups. The results also indicated that stem diameter, the number of branches, heads per plant and grains per head had the highest correlation with the first component, and grain yield, flower colour, flowering initiation and plant height had the highest correlation with the second component. These traits can be considered as an appropriate index for the selection of elite safflower genotypes for breeding varieties suited to cultivation in semi-arid conditions.