نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه زراعت و اصلاح نباتات دانشکده کشاورزی دانشگاه ایلام، ایلام،ایران
2 گروه زراعت و اصلاح نباتات دانشکده کشاورزی دانشگاه ایلام، ایلام
3 گروه زراعت و اصلاح نباتات دانشکده کشاورزی دانشگاه ایلام، ایلام، ایران.
4 گروه زراعت و اصلاح نباتات دانشکده کشاورزی دانشگاه ایلام، ایلام، ایران
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Wheat is one of the primary cereals in most countries, and in recent decades, its cultivation has been significantly impacted by environmental conditions due to climate change. Therefore, an experiment was conducted during the 2020-2021 agricultural year to examine the response of photosynthetic pigments and the yield of different wheat cultivars to the combined application of bacteria and sulfur under rainfed conditions. This factorial experiment was conducted in a randomized complete block design with three replications. The experimental factors included four wheat cultivars: Eivan, Sardari, Homa, and Azar 2, sulfur treatment at two levels: foliar spray with distilled water as a control and foliar spray with sulfur and bacterial treatment at two levels: without inoculation (control) and inoculation with Azospirillum bacteria. The results showed that the highest grain yield (3030 kg/ha) was observed in the Eivan cultivar with the application of Azospirillum bacteria. Inoculation with Azospirillum bacteria increased the grain yield of the Eivan and Sardari cultivars by 17.9% and 42%, respectively, while no statistically significant effect was observed on the grain yield of the Homa and Azar 2 cultivars. The results indicated that sulfur spraying and bacterial application improved photosynthesis. Under rainfed conditions, the Eivan cultivar had significantly higher grain yield compared to the Sardari, Homa, and Azar 2 cultivars and produced a higher yield with bacterial application. Azospirillum bacteria increased leaf photosynthesis. Plant nutrition management and the use of growth-promoting bacteria, with their physiological effects, can be considered strategies for improving yield under rainfed conditions.
کلیدواژه‌ها [English]
EXTENDED ABSTRACT
Wheat is a crucial agricultural crop, and increasing its production by leveraging its genetic potential and environmental responsiveness plays a significant role in reducing hunger and boosting global food production. Utilizing the potential of beneficial soil organisms can be an economically viable strategy to mitigate the effects of drought stress in crops, aligning with the principles of sustainable agriculture. Rhizosphere bacteria that stimulate plant growth are among the biological resources that enhance plant growth through both direct and indirect methods. Azospirillum bacteria are an example of such growth-promoting bacteria. These bacteria can produce and secrete active biological substances in the root environment, creating conditions that foster root system development, enhance nutrient uptake, and facilitate the biological stabilization of nitrogen and phosphorus, ultimately increasing yield. Among the nutrients, sulfur is particularly used to reduce the pH of alkaline soils. As a widely used fertilizer, sulfur not only contributes to about 15% of the dry weight of wheat plant biomass but also lowers soil pH and improves the absorption of micronutrients. Additionally, it enhances water retention in the soil. Given the abundance of sulfur and its beneficial effects on plants, as well as the physical and chemical characteristics of soils in arid and semi-arid regions, and considering the positive impacts of using growth-promoting bacteria under stress conditions to stimulate plant growth and development, this research aims to investigate the role of sulfur and Azospirillum bacteria in different wheat cultivars by improving photosynthesis and yield.
The experiment aimed to investigate the response of photosynthetic pigments and the yield of wheat cultivars to the combined application of bacteria and sulfur under rainfed conditions during the 2020-2021 crop year. It was conducted using a factorial design within a randomized complete block design, with three replications. The experimental factors included four wheat cultivars: Eivan, Sardari, Homa, and Azar 2. The sulfur treatment had two levels: foliar spraying with distilled water as a control and foliar spraying with sulfur. The bacterial treatment also had two levels: non-inoculation (control) and inoculation with Azospirillum bacteria.
The results showed that the highest seed yield (3030 kg/ha) was observed in the Eivan variety with the use of Azospirillum bacteria. Inoculation with Azospirillum bacteria increased the grain yield of the Eivan and Sardari cultivars by 17.9% and 42%, respectively, while the increase in grain yield for the Homa and Azar 2 cultivars was not statistically significant. Based on the comparison of average treatments, the highest amount of chlorophyll a following bacterial inoculation was observed in the Eivan cultivar (4.298 mg g⁻¹ FW), while the lowest amount was observed in the Azar 2 cultivar (2.531 mg g⁻¹ FW). Among the cultivars studied under rainfed conditions, the Eivan cultivar showed a significant advantage in grain yield compared to the Sardari, Homa, and Azar 2 cultivars, producing a higher yield with the use of bacteria. Additionally, Azospirillum bacteria increased the rate of leaf photosynthesis.
Sulfur increases photosynthetic pigments (chlorophyll a, chlorophyll b, and total chlorophyll) and enhances photosynthesis. Based on the results, it can be concluded that new wheat cultivars, such as the Eivan variety, showed significant superiority compared to older cultivars like Sardari. The Eivan variety had a high grain yield and produced even more yield with the use of bacteria. Bacterial inoculation increased the concentration of chlorophyll a in the leaves of the wheat cultivars. Plant nutrition management and the use of growth-promoting bacteria, through their effects at the physiological level, can be recommended as strategies to improve performance under rainfed conditions.
Methodology, software, formal analysis, writing—original draft preparation, Z.K; conceptualization, visualization, investigation, validation, resources, data curation, supervision, M.J.Z.; writing—review and editing, A.F.; writing—review and editing, B.Z
All authors have read and agreed to the published version of the manuscript. All authors contributed equally to the conceptualization of the article and writing of the original and subsequent drafts.
“Not applicable”
Hereby, we extend our thanks and appreciation to Ilam University for providing the necessary facilities for conducting this research.
The authors avoided data fabrication, falsification, plagiarism, and misconduct.
The author declares no conflict of interest.
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