نوع مقاله : پژوهشی
نویسندگان
1 گروه زراعت، دانشکده تولید گیاهی، دانشگاه علوم کشاورزی و منابع طبیعی گرگان
2 استاد تمام،گروه زراعت، دانشکده تولید گیاهی، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ، ایران
3 گروه زراعت، دانشکدهتولید گیاهی، دانشگاه علوم کشاورزی و منابع طبیعی گرگان
4 استاد تمام، موسسه کشاورزی تاسمانی، دانشگاه تاسمانی، هوبارت، استرالیا
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Introduction
waterlogging and salinity stress are expected stresses in cultivated areas, and their concurrent happening can lead to a greater decrease in growth and yield compared to each stress alone. Combined stresses also generate a wide range of physiological and biochemical responses in plants. While the physiological and molecular mechanisms of plant responses to these environmental restrictions have been studied in detail, the basic mechanisms of plant tolerance to their combined stress are much less known.
Materials and methods
To investigate the effect of foliar spraying of melatonin and nutrients on barley cultivars under conditions of waterlogging stress with salt water, a factorial experiment with 3 factors in the form of a completely randomized design with six replications in pots in the open environment in two crop years 1400-1401 and was executed in 1401-1402. The test factors include four cultivars of barley (Mahor, Auxin, Sahra, Fardan), waterlogging stress with salt water (two levels: no stress and applied stress), foliar application of melatonin and nutrients (three levels: no foliar application, foliar application in It was the stage of tillering and stemming. In this study, various parameters including root length and volume, and dry weight of root and shoot were measured. Also, the ratio of root weight to shoot weight, iron and manganese concentration, and the ratio of sodium to potassium, calcium to potassium, and nitrogen to potassium were scrutinized and analyzed.
Results and discussion:
The results in four varieties of barley showed that waterlogging with salt water caused a decrease of 9.4 cm in root length, 0.2 cubic cm in root volume, 0.5 g in root dry weight, and 0.4 g in dry weight. Shoots, the root-to-shoot ratio was 7.8, the ratio of calcium to potassium was 0.01, the ratio of nitrogen to potassium was 0.18, the amount of iron was increased by 8 mg/kg, and the amount of manganese was 11 mg/kg, and the difference in the ratio Sodium to potassium reached 11. Foliar application of nutrients and melatonin reduced the effects of stress and improved plant growth, and root length and volume were 14.5, 11.3, 15.3, 16.4 cm, and 2.78, 24 cm respectively. 2.2, 4.18, and 3.43 cubic centimeters corresponding to Mahor, Axin, Sahra, and Fardan cultivars after foliar spraying at the tillering stage to 19.2, 15.7, 19.9 and 21 centimeters and 4.36, 3.73, 5.73 and 4.98 cubic centimeters improved. Also, the amounts of iron and manganese in the roots under stress conditions were 13.25, 12.75, 12.83, and 13.42 mg/kg and 17, 17.5, 18.33, and 16 mg/kg, respectively. Regarding Mahur, Axin, Sahra, and Fardan cultivars after foliar spraying in the tillering stage iron to 7.75, 8.08, 7.92, and 7.67 mg/kg, and manganese to 11.42, 5. 12, 10.67 and 12.08 mg/kg decreased.
Conclusions:
Waterlogging and salinity stress significantly affected root and shoot growth and led to an imbalance in ion homeostasis. The use of nutrients and melatonin in waterlogging stress with salt water reduced the negative effects of stress through different mechanisms, improving growth parameters and ionic homeostasis in roots and aerial organs. Regarding the concentration of iron and manganese, it can be pointed out that spraying reduces the concentration of these elements under stress and reduces the possibility of toxicity. It should also be noted that foliar spraying was much more effective at the tillering stage than at the stemming stage, which was probably due to the longer duration of the melatonin effect, the absorption of more nutrients, and the regeneration of tissues. Therefore, spraying melatonin and nutrients can be considered as a suitable solution to reduce the damage of this stress in barley cultivars.
کلیدواژهها [English]