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This study aimed to investigate the effects of drought stress at the flowering stage on the physiological and molecular responses of the genes involved in the brassinosteroid pathway of two chickpea cultivars (ILC1799: drought tolerant, and ILC3279: drought sensitive). The drought resulted in significant reductions in chlorophyll a, chlorophyll b, total chlorophyll and carotenoid content in both cultivars, and had significantly lesser effects on the tolerant cultivar, Samin, compared to that of ILC3279. However, the relative water content, the osmotic potential and the cell membrane stability were less affected by drought in both cultivars. The proline content and peroxidase activity increased significantly under drought stress in both cultivars, with a higher amount in Samin (ILC1799). Members of the BES1 family positively mediate brassinosteroid signaling and play an important role in regulating plant stress responses. The expression of these genes was analyzed in chickpea cultivars under drought. Further, a genome-wide analysis of BES1 genes in the chickpea genome was conducted. Six CaBES1 genes were identified in total, and their phylogenetic tree, gene structures, and conserved motifs were determined. CaBES1 gene expression patterns were analyzed using a transcription database and quantitative real-time PCR analysis. The results revealed that the expression of CaBES1 genes are different in response to various plant stresses. The expression levels of CaBES1.1, CaBES1.2, CaNAC72 and CaRD26 genes were measured by using qRT-PCR. The relative expression of CaBES1.2 in the drought conditions was significantly downregulated. In contrast to CaBES1.1 and CaBES1.2, the expression of CaRD26 and CaNAC72 showed a significant increase under drought stress. The expression of CaRD26 and CaNAC72 genes was significantly higher in the Samin cultivar compared to that of ILC3279 cultivars. [ABSTRACT FROM AUTHOR]

Seed priming and foliar application are two crop management practices that can increase grain yield and quality. The research aimed to assess the influence of seed priming and foliar application on rainfed wheat. Two field experiments with two seed priming rates (control and priming) and five foliar applications [control, urea (4%), silicon (4 mM), FeSO4.7H2O (0.6%), and ZnSO4.7H2O (0.4%)] at the anthesis/Z61 stage were conducted. Seeds were primed for 12 h at 25 ± 2°C, by soaking in an aerating solution [urea (20 g L−1) + FeSO4.7H2O (50 ppm) + ZnSO4.7H2O (50 ppm) + silicon (20 mg L−1)]. Seed weight-to-solution volume ratio was 1:5 (kg L−1). A pot experiment was also conducted to examine the effect of priming on root growth. Overall, combined seed priming and foliar application induced a positive impact on physiological traits and attributes. Maximum chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid concentrations (1.58, 0.669, 2.24, and 0.61 mg g−1 FW), membrane stability index (77.31%), superoxide dismutase and peroxidase activity (0.174 and 0.375 Unit mg−1 protein), 1,000-grain weight (35.30 g), biological yield, grain yield (8,061 and 2,456 kg ha−1), and minimum malondialdehyde concentration (3.91 µg g−1 FW) were observed in seed priming combination with ZnSO4 foliar application. The highest glycine betaine concentration (6.90 mg g−1 DW) and proline (972.8 µg g−1 FW) were recorded with the co-application of seed priming and foliar urea spraying. Foliar application of ZnSO4, FeSO4, and urea drastically enhanced grain Zn (29.17%), Fe (19.51%), and protein content (increased from 11.14% in control to 12.46% in urea foliar application), respectively. Compared to control, seed priming increased root length, root volume, and dry mass root by 8.95%, 4.31%, and 9.64%, respectively. It is concluded that adequate Zn, Fe, silicon, and N supply through seed priming and foliar applications of these compounds at the terminal stage of rainfed wheat alleviates drought stress and improves GY and biofortification. [ABSTRACT FROM AUTHOR]

The purpose of the experiment was to investigate the relationship between the accumulation of polyamines during the filling period of wheat grain with yield and grain protein under dryland and supplemental irrigation (SI) conditions and also the effect of foliar spraying of urea on the amount of polyamines in grain a factorial experiment was conducted based on randomized complete block design with three replications during two cropping seasons. The examined treatments included water availability (dryland and SI), wheat cultivars (Homa, Sardari, Rijaw, Ouhadi, and Azar2), and foliar application of urea (control and 4% urea foliar application). The results demonstrated that SI (10%) reduced and urea foliar (12%) application increased the percent of grain protein. SI reduced the contents of three PAs by 24%: spermine, spermidine, and putrescine. But urea foliar application increased the three PAs in the first and second years by 31% and 27% in dryland conditions and 12% and 4% in SI conditions, respectively. These results indicated that there is less need for PAs in SI conditions, and they thus exhibit poorer accumulation in the grain; in dryland conditions, however, their content increases with greater access to foliar nitrogen. Older cultivars Sardari and Azar 2 had more polyamines. According to the observed positive correlation between 1000-grain weight and the three PAs under stress conditions, PAs are probably involved in the improvement of grain filling, and urea foliar application can affect drought tolerance by increasing PA accumulation. Moreover, cadaverine exhibited a different function from the other PAs. [ABSTRACT FROM AUTHOR]

Drought is a major obstacle for wheat production around the world. Seed priming and foliar nutrition spray at various stages of growth have both been shown to be beneficial in lowering stress and improving wheat grain production. For this reason, this experiment was conducted in the form of split plots in a randomized complete block design with two factors including seed priming (Main factor) and foliar application (Sub-factor), and 3 replications during the 2018–2019 and 2019–2020 cropping seasons. Eight seed priming treatments including control (without seed priming), water (hydro-priming), urea (2%), zinc sulfate (0.6%), potassium chloride (1%), calcium chloride (1.4%), vitaspirin (1 g L−1), and cytokinin (50 mg L−1) were randomized on the main plot, and 3 foliar application treatments including control (without foliar application), urea (4%), and vitaspirin (0.1%) were randomized on a sub-plot. The results showed that the thousand kernel weight had not had much effect on grain yield in this experiment. Furthermore, treatments that increased the number of grains had a positive impact on enhancing grain yield. In the 2020–2019 cropping season, none of the seed priming treatments enhanced grain yield because of temperature and rainfall constraints. This demonstrated the role of early growth conditions in the effectiveness of seed priming treatments. As a result, seed priming treatments without foliar application under dryland conditions cannot be recommended due to the unpredictability of weather conditions. In both cropping seasons, seed priming with calcium chloride + foliar application of vitaspirin was one of the top three treatments in terms of grain yield. [ABSTRACT FROM AUTHOR]

Six plots include three plots of solid-set sprinkler and three plots of border irrigation methods in Kangavar plain (Iran), were evaluated under farmers' management standards. Wheat was grown in each of the plots and all the irrigation events were evaluated. The average values of irrigation indexes, distribution uniformity, potential application efficiency of the low quarter, application efficiency of the low quarter, application efficiency, deep percolation ratio, adequacy of irrigation, and water requirement efficiency in border-irrigated plots were 80.4%, 80.4%, 69.1%, 80.5%, 19.5%, 53.1%, and 80.8%, respectively. Those values indicated much better performance than the average values for the movable solid-set sprinkler-irrigated plots, which were 55.8%, 44.7%, 37.2%, 41.5%, 38.6%, 85.0% and 96.5%, respectively. So the system design and the farmers' management are suitable with border irrigation in accordance with the experiences they have gained with time. That was not the case for the movable sprinkler irrigation system, in which the performance indexes are below the recommended minimum values. Therefore, the efficiency of an irrigation system is not independent of its management, and the farmer's skill on the irrigation system is one of the most important indices for selecting a suitable irrigation system. Also, improving farmer's management is the most appropriate way for improving irrigation performance. [ABSTRACT FROM AUTHOR]

Potato (Solanum tuberosum L.) is a relatively sensitive crop to water stress and is widely cultivated north hemisphere and especially in Iran. Today a need for water-conserving irrigation strategies is becoming increasingly important in arid and semi-arid countries such as Iran. In the present study, field experiments comparing different irrigation strategies and irrigation levels on potato tuber yield, yield components and irrigation water use efficiency (IWUE) were carried out in a loam soil during growing seasons of 2011 and 2012. There were seven surface drip irrigation treatments including: (1) full irrigation (FI); irrigated when 35 percent of the available water at 0.2m depth was extracted, (2,3,4) deficit irrigation (DI): received 80 (DI80), 70 (DI70) and 60% (DI60) of full irrigation at each irrigation, and (5,6,7) partial root zone drying (PRD): received 80 (PRD80), 70 (PRD70) and 60% (PRD60) of full irrigation at each irrigation, respectively. Results showed that irrespective of irrigation levels, DI and PRD treatments produced lower fresh tuber yield, while increased the IWUE in DI70, DI60, PRD80 and PRD70. DI and PRD treatments significantly reduced the leaf area index, tuber weight and tuber number per plant. Tuber yield was more correlated to tuber weight (r = 0.96) than to tuber number (r = 0.82). Based on this study, the DI80 and DI70 can be used for alternative irrigation strategies except where water resources are not limited or irrigation water is not expensive. [ABSTRACT FROM AUTHOR]

A field experiment was undertaken to investigate the effectiveness of arbuscular mycorrhizal (AM) fungi (Funneliformis mosseae) on nutrients uptake, biomass production, yield components, chlorophyll content and essential oil yield and composition in fenugreek (Trigonella foenum graecumL.), coriander (Coriandrum sativumL.) and nigella (Nigella sativa L.). All these medicinal plants were grown with or without AM fungi colonization. A randomized complete block design with three replications was employed to compare the treatments. Mycorrhiza colonization increased shoot P, Ca, Zn and Fe contents. However, K contents of fenugreek and nigella was not affected by AM colonization. AM colonization significantly increased the growth and yield components, chlorophyll content, and EO yield as compared to non-colonized plants. Changes in EO composition were detected in AM-colonized fenugreek, coriander and nigella plants. The contents of ether, limonene, carvone, iso-dihydrocarvone, myristicin, p-cymene, decanal, 2-decenal and n-dihydrocarvone were enhanced in EO obtained from AM-colonized plants, while AM colonization resulted in a lesser content of β-phellandrene, iso-dihydrocarveol, 1-decanol, cis-sabinol, pentadecanal, 2-pentadecanone,6,10,14-trimethyl, cis-9,17-octadecadienal, phytol and trans-2-dodecenal.ABSTRACT FROM PUBLISHERCopyright of Journal of Essential Oil Research is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. [ABSTRACT FROM AUTHOR]

Drought is one of the main constraints restricting the growth and yield of crop plants. It is suggested that antioxidants, like salicylic acid (SA) and ascorbic acid (AA), may enhance drought tolerance in plants. Results showed that seed yield, plant biomass, plant height and water use efficiency were decreased whereas protein content and soluble carbohydrates were increased as the result of complete drought stress. The maximum plant height and the highest protein content of the chickpea belonged to ILC482 and Kurdistan cultivars respectively. The plant biomass was increased by application of salicylic and ascorbic acids as compared with control plants significantly. The results showed that ascorbic acid application increased rate of biological water use efficiency significantly as compared with control plants. Application of salicylic acid led to significant increase in protein content of leaves in complete drought stress condition. Application of ascorbic acid at non-stress (control) condition resulted in the highest rate of economical water use efficiency. [ABSTRACT FROM AUTHOR]