نوع مقاله : مقاله پژوهشی
عنوان مقاله English
نویسندگان English
Extended Abstract
Introduction: Pepper is an essential fruit vegetable that is widely grown around the world, and its global demand is continuously increasing. However, pepper is a crop that is sensitive or semi-sensitive to salinity, which poses a significant challenge for its cultivation in many regions. Salinity can be a major abiotic stress that affects pepper production, particularly in arid and semi-arid areas where soil salinity is a prevalent issue. High concentrations of soluble salts, such as sodium, chloride, and sulfate, in the soil can disrupt the plant's ability to absorb water and essential nutrients, leading to reduced growth, yield, and quality of the pepper crop. Furthermore, the imbalance of nutrients in saline soils can interfere with the plant's capacity to efficiently utilize applied fertilizers. To overcome these challenges and meet the increasing global demand for pepper, researchers and growers must adopt integrated approaches that consider the complex interactions between soil salinity, nutrient availability, and pepper plant physiology. This may involve the application of soil amendments to mitigate salinity, and the implementation of precise irrigation and fertilization management practices to ensure the sustainable production of high-quality pepper crops.
Materials and Methods: The present research was conducted in 2021 in a greenhouse in Tiran with an average daytime temperature of 26-28ºC and a night temperature of 16-18ºC in the form of a completely randomized design with 3 replications. Greenhouse red bell pepper seeds, variety "Westland 8108" were planted in peat moss and perlite in the seedling trays, and about three weeks later, when the seedlings reached the stage of 4-6 true leaves, they were planted in the main bed. The treatments include the application of Sal-fit (polyhydroxycarboxylic calcium), foliar spraying with auxin + gibberellin, 25% reduction of nutrient solution concentration, fruit pruning, and common greenhouse nutrient solution (as a control). Sal-Fit treatment with a solution based on polyhydroxycarboxylic calcium was applied as an irrigation fertilizer at the rate of 50 kg per hectare in 3 stages of greenhouse irrigation. Auxin and gibberellin foliar spraying each in a concentration of 10 µM and combination with each other with a time interval of 24 h was applied on the target bell pepper plants in the fruiting stage. The nutrient solution reduction treatment was applied in such a way that 25% of water was added to the concentration recommended by the greenhouse nutrition expert at each time of fertilization (solution spraying and irrigation fertilizer), and then foliar spraying or irrigation fertilizer was done with a new solution. For the treatment, pruning was done after the emergence of fruits by keeping the number of 5-7 fruits per plant and removing the rest of the fruits. At the end of the research, some growth and physiological characteristics of sweet pepper were investigated
Results and Discussion: The findings indicated that the application of the Sal-Fit treatment yielded a statistically significant and favorable impact on growth characteristics in the presence of severe soil salinity stress. Additionally, this treatment exhibited the lowest incidence of fruit malformation, as well as a higher relative content of fruit juice and organic acid percentage. The enhancement of soluble solids percentage, nitrogen and calcium content indicators, and reduction in flower and fruit drop, collectively contributed to the overall improvement in the quality of the product. In comparison to alternative treatments, fruit pruning yielded a statistically significant, albeit modest, impact on various traits, including the relative concentration of fruit juice, percentage of soluble solids, shoot nitrogen content, fruit taste, fruit length, and yield, when compared to the control group. Additionally, fruit pruning demonstrated a greater efficacy in reducing the duration of fruit ripening, as well as flower and fruit drop, in contrast to other treatments. The findings demonstrate that the reduction of the nutrient solution concentration by 25%, as advised by the greenhouse nutrition specialist, had an impact on all the characteristics, with the exception of the quantity of fruit categorized as grade 1, grade 2, and grade 3, as well as the firmness of the fruit's texture.
Conclusion: According to research findings, the application of chemical fertilizers in saline soils may result in varying effects on crop yield, which could either be positive, negative, or neutral. Sal-Fit, also known as polyhydroxy carboxylic calcium, is a chemical compound. This particular solution has demonstrated high efficacy in environments characterized by elevated salinity and alkalinity. It effectively mitigates soil salinity by resolving the aforementioned issue to a level deemed appropriate. The study concluded that the beneficial impacts of anti-salt and alkali compounds are attributed to their positive influence on various physical and chemical characteristics of the soil, such as SAR, PH, EC, and ESP. These factors ultimately enhance nutrient accessibility for plants, augment water availability and foster interactions between phenolic and carboxylic groups.
کلیدواژهها English
