نوع مقاله : مقاله پژوهشی
نویسندگان
1 استادیار بخش تحقیقات خاک و آب، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی استان آذربایجان شرقی،سازمان تحقیقات، آموزش و ترویج کشاورزی،
2 گروه اکوفیزیولوژی گیاهی دانشکده کشاورزی، دانشگاه تبریز، تبریز، ایران
3 دانشیار بخش تحقیقات خاک و آب، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی استان آذربایجانشرقی، سازمان تحقیقات، آموزش و ترویج کشاورزی،
4 دانشیار موسسه تحقیقات خاک و آب، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
The factorial experiment based on a randomized complete block design was conducted with three replications at the research greenhouse of Tabriz University in 2017. The experimental factors include three levels of salinity stress (non-saline, salinity 3 and 6 dS/m) from the source of sodium chloride, foliar spraying in three levels without hormonal and nutritional foliar spraying, foliar spraying of 2 mM silicon and foliar spraying of 1mM salicylic acid, and the third factor, bacterial inoculation in four levels included: no inoculation, inoculation with Azosprilium, inoculation with Azotobacter and combined inoculation of two bacteria. The results of this research showed that the salt stress reduced the growth and yield of garlic. Spraying of salicylic acid and silicon and inoculation with bacteria improved potassium absorption, plant height, and leaf surface area, number of leaves per plant, yield components, biomass, and yield of garlic. The treatments significantly reduced the sodium concentration in both roots and leaves. The positive effects of the proposed treatments not only improved plant growth and performance under salinity stress conditions but also under non-saline conditions. Among the studied treatments, salicylic acid and silicon foliar applications along with the combined use of Azospirillium and Azotobacter showed more favorable effects on the growth and productivity of garlic than the other treatments. Finally, it was suggested to use growth-promoting bacteria in combination with salicylic acid and silicon solution spraying to mitigate the effects of salinity stress in garlic plants.
کلیدواژهها [English]
The effects of plant growth-promoting bacteria, foliar sprays of salicylic acid and silicon on growth parameters of garlic under salt stress
Extended Abstract
Salinity stress is a global problem that negatively affects plant growth and productivity. It is the second most common form of environmental stress after drought stress, and it is prevalent in Iran and worldwide. Salinity stress causes various physiological changes in plants, leading to hindered growth. Several solutions have been suggested to alleviate the impact of salt stress, and one of the most effective methods is the use of plant growth-promoting bacteria. Additionally, silicon, a vital nutrient, and salicylic acid, a stress resistance hormone, have distinct roles in enhancing plant resistance to salt stress. Garlic is a highly valuable and widely utilized product in the food and pharmaceutical industries globally, with significant economic value. However, its production can decrease under salt stress.
The purpose of this study was to examine the potential impact of growth-promoting bacteria, salicylic acid, and silicon on enhancing the growth of garlic plants when exposed to high levels of salt.
This study was performed using a factorial design with randomized complete blocks in three replications. The main factors of the experiment were the foliar spraying of salicylic acid and silicon, as well as the use of growth-stimulating bacteria (Azospirillum and Azotobacter) under salt stress. The experiment took place in a greenhouse, using perlite as the culture medium. The bacteria were used both individually and in combination.
Salinity stress had negative effects on various aspects of plant growth, including plant height, leaf growth, number of leaves, potassium levels in roots and leaves, plant weight, and garlic yield. Conversely, it led to an increase in sodium concentration in both the root and leaf tissues. The application of growth-stimulating bacteria (Azospirillum and Azotobacter), along with salicylic acid and silicon foliar spray, improved plant growth, increased potassium levels in leaves and roots, and enhanced garlic yield in both saline and non-saline conditions. These treatments also reduced the absorption and accumulation of sodium in plant tissues. Among the tested treatments, the combination of foliar spraying with salicylic acid, and the use of Azospirillum and Azotobacter, had the best results in enhancing the growth and productivity of garlic under salt stress. Nevertheless, other treatments, whether applied individually or in combination, also demonstrated positive effects on plant growth in both saline and non-saline conditions.
The results of this research clearly showed that salt stress can cause a decrease in garlic yield by reducing the overall growth of the plant. Using biological fertilizers to manage plant growth is an effective strategy for increasing plant production under salt stress. The utilization of growth-promoting bacteria, particularly when used in combination, can enhance plant growth in conditions of salt stress. Based on this, it is recommended to use growth-promoting bacteria in combination with salicylic acid to enhance plant growth under salt stress.