نوع مقاله : مقاله کامل علمی پژوهشی
نویسندگان
1 گروه علوم باغبانی، دانشکده تولید گیاهی، دانشگاه علوک کشاورزی و منابع طبیعی گرگان، ایران
2 گروه علوم باغبانی، دانشکده تولید گیاهی، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، ایران
3 گروه علوم باغبانی، دانشکده کشاورزی، دانشگاه لرستان
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Background and Objective: Drought is one of the most important factors restricting agricultural production, which seriously affects crop yield. Water deficit in plants leads to disturbance in physiological processes such as reduction of photosynthesis. Silicon is the second most abundant element in the earth's crust, which plays a role in plant resistance to biotic and abiotic stresses. Therefore, according to the medicinal importance of Satureja rechingeri Jamzad, the objective of this experiment is to investigation the effect of silicon and nanosilicon on leaf length and width traits, photosynthetic pigments and chlorophyll fluorescence parameters of Satureja rechingeri Jamzad under drought stress.
Material and Methods: this experiment was performed as factorial based on the randomized complete design in three replications under greenhouse conditions. The factors include drought stress in three levels of severe stress, medium stress and none stress respectively (50-60, 70-80 and 90-100% of soil moisture based on field capacity) and silicon foliar spraying in five levels (0, 50 and 100 mg/L of silicon, 50 and 100 mg/L of nanosilicon).
Results: The interaction effect of silicon and drought stress on leaf width, all chlorophyll fluorescence parameters and concentration of photosynthetic pigments except carotenoid was significant(p<0.05). The highest amount leaf width was obtained in the treatment of none stress with foliar spraying of 50 mg/l silicon. the highest contents of chl-a and total chlorophyll was obtained in the treatment of nanosilicon 50 mg/L under none stress and the highest amount of chlorophyll b was achieved with the treatment of nanosilicon 50 and silicon 100 mg/L under none stress treatment. The lowest amount of minimal fluorescence (F0) belonged to the control treatment and the highest amount of maximal fluorescence (Fm) and variable fluorescence (FV) was observed under medium stress without foliar. Silicon 50, 100 mg/L and nanosilicon 50 mg/L treatments in none stress in addition to zero and 50 mg/L silicon concentrations in medium stress had the highest maximum quantum yield of photosystem II (Fv/Fm). The highest efficiency of water splitting system (Fv/F0) was observed in silicon 50 mg/L treatment under none stress. The highest electron transport flux per RC (ET0/RC) was obtained in the treatment of 100 mg/L nanosilicon in none stress. The highest trapped energy flux per RC (TR0/RC) and dissipated energy flux per RC (DI0/RC) were obtained under severe stress without foliar spraying. The highest quantum yield of electron transport (ɸE0) was observed in control, silicon 50 and 100 mg/L and nanosilicon 50 mg/L treatments under medium stress.
Conclusion: Severe drought stress caused a decrease in photosynthetic pigments and chlorophyll fluorescence indices, and the application of silicon and nanosilicon improved the destructive effects of drought stress on the amount of photosynthetic pigments and fluorescence indices.
کلیدواژه‌ها [English]
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