تاثير محلول نانوكلات پتاسيم بر برخي ويژگي‌هاي فيزيولوژيكي و مورفولوژيكي گندم تحت تنش خشكي

Effect of nano –chelated potassium solution on some physiological and morphological characteristics of wheat under drought stress

از آﻧﺠﺎﯾﯽ ﮐﻪ ﭘﺘﺎﺳﯿﻢ ﻧﻘﺶ ﺑﺴﺰاﯾﯽ در ﻓﻌﺎﻟﯿﺖﻫﺎي ﺣﯿﺎﺗﯽ ﮔﯿﺎه داﺷﺘﻪ و ﺟﺰو ﻣﻬﺎرﮐﻨﻨﺪه ﻫﺎي اﺛﺮات ﻣﺨﺮب ﻧﺎﺷﯽ از ﺗﻨﺶ ﺧﺸﮑﯽ ﻣﯽ ﺑﺎﺷﺪ. ﺑﻪ ﻣﻨﻈﻮر ﺑﺮرﺳﯽ ﺗﺎﺛﯿﺮ ﻧﺎﻧﻮﮐﻼت ﭘﺘﺎﺳﯿﻢ ﺑﺮ ﺑﺮﺧﯽ وﯾﮋﮔﯽ ﻫﺎي ﻓﯿﺰﯾﻮﻟﻮژﯾﮑﯽ و ﻣﺮﻓﻮﻟﻮژﯾﮑﯽ ﮔﻨﺪم در ﺷﺮاﯾﻂ ﺗﻨﺶ ﺧﺸﮑﯽ، آزﻣﺎﯾﺸﯽ ﺑﻪ ﺻﻮرت ﻓﺎﮐﺘﻮرﯾﻞ در ﻗﺎﻟﺐ ﻃﺮح ﭘﺎﯾﻪ ﮐﺎﻣﻼً ﺗﺼﺎدﻓﯽ ﺑﺎ ﺳﻪ ﺗﮑﺮار ﺑﻪ ﺻﻮرت ﮐﺸﺖ ﮔﻠﺪاﻧﯽ در ﮔﻠﺨﺎﻧﻪ داﻧﺸﮑﺪه ﮐﺸﺎورزي داﻧﺸﮕﺎه ﻣﺤﻘﻖ اردﺑﯿﻠﯽ اﺟﺮا ﺷﺪ. ﻓﺎﮐﺘﻮرﻫﺎي ﻣﻮرد ﺑﺮرﺳﯽ ﺷﺎﻣﻞ ﻓﺎﮐﺘﻮر اول ﺗﻨﺶ ﺧﺸﮑﯽ در ﺳﻪ ﺳﻄﺢ ﭘﺘﺎﻧﺴﯿﻞ اﺳﻤﺰي )4،-8- و ﺻﻔﺮ ﺑﺎر(، ﻓﺎﮐﺘﻮر دوم ارﻗﺎم ﮔﻨﺪم )رﺻﺪ و ﮔﺎﺳﮑﻮﯾﻦ( و ﻓﺎﮐﺘﻮر ﺳﻮم ﺷﺎﻣﻞ ﻧﺎﻧﻮﮐﻼت ﭘﺘﺎﺳﯿﻢ )ﻋﺪم ﮐﺎرﺑﺮد ﻧﺎﻧﻮﮐﻼت ﭘﺘﺎﺳﯿﻢ، 35 و 65 ﻣﯿﻠﯽ ﮔﺮم در ﻟﯿﺘﺮ( ﺑﻮد. ﻣﺤﻠﻮل ﭘﺎﺷﯽ ﻧﺎﻧﻮﮐﻼت ﭘﺘﺎﺳﯿﻢ و ﺗﻨﺶ ﺧﺸﮑﯽ ﺑﺎ ﭘﻠﯽ اﺗﯿﻠﻦ ﮔﻠﯿﮑﻮل 6000 ﺑﻪﻃﻮر ﻫﻤﺰﻣﺎن ﺑﻪ ﮔﯿﺎﻫﺎن در ﻣﺮﺣﻠﻪي ﺳﻪ ﺗﺎ ﭘﻨﺞ ﺑﺮﮔﯽ ﺑﻪ ﻣﺪت ﭘﻨﺞ روز اﻋﻤﺎل ﺷﺪ و ﺳﭙﺲ ﻧﻤﻮﻧﻪ ﺑﺮداري از ﻧﻤﻮﻧﻪﻫﺎي ﺷﺎﻫﺪ و ﺗﯿﻤﺎري اﻧﺠﺎم ﮔﺮﻓﺖ. ﻣﺤﻠﻮلﭘﺎﺷﯽ ﻧﺎﻧﻮﮐﻼت ﭘﺘﺎﺳﯿﻢ ﻣﻮﺟﺐ اﻓﺰاﯾﺶ ﻣﻘﺪار رﻧﮕﺪاﻧﻪ ﻫﺎي ﻓﺘﻮﺳﻨﺘﺰي، ﺷﺎﺧﺺ ﮐﻠﺮوﻓﯿﻞ ﺑﺮگ، ﻋﻤﻠﮑﺮد ﮐﻮاﻧﺘﻮﻣﯽ، ارﺗﻔﺎع اﻧﺪام ﻫﺎي ﻫﻮاﯾﯽ و زﻣﯿﻨﯽ، وزن ﺧﺸﮏ و ﺗﺮ ﺳﺎﻗﻪ و رﯾﺸﻪ ﮔﺮدﯾﺪ. ﺗﻨﺶ ﺧﺸﮑﯽ ﻣﻮﺟﺐ ﮐﺎﻫﺶ ﻋﻤﻠﮑﺮد ﮐﻮاﻧﺘﻮﻣﯽ، ﻣﻘﺎدﯾﺮ ﮐﻠﺮوﻓﯿﻞ b a و ﮐﻠﺮوﻓﯿﻞ ﮐﻞ و ﻣﯿﺎﻧﮕﯿﻦ ﻃﻮل ﺳﺎﻗﻪ، ﻃﻮل ﻣﯿﺎﻧﮕﺮه، ﻃﻮل ﺑﺮگ، ﻃﻮل رﯾﺸﻪ و ﻫﻤﭽﻨﯿﻦ ﻣﻮﺟﺐ ﮐﺎﻫﺶ وزن ﺗﺮ و ﺧﺸﮏ ﺳﺎﻗﻪ ﺷﺪ. ﺑﯿﻦ ارﻗﺎم ﻣﻮرد ﻣﻄﺎﻟﻌﻪ رﻗﻢ ﮔﺎﺳﮑﻮﯾﻦ واﮐﻨﺶ ﻣﻨﺎﺳﺐﺗﺮي ﻧﺴﺒﺖ ﺑﻪ ﺗﻨﺶ ﺧﺸﮑﯽ ﺗﺤﺖ ﻣﺤﻠﻮلﭘﺎﺷﯽ ﻧﺎﻧﻮﮐﻼت ﭘﺘﺎﺳﯿﻢ ﻧﺸﺎن داد ﮐﻪ ﻧﺸﺎن دﻫﻨﺪه ﺗﺤﻤﻞ ﺑﯿﺸﺘﺮ اﯾﻦ رﻗﻢ ﻧﺴﺒﺖ ﺑﻪ ﺗﻨﺶ ﺧﺸﮑﯽ اﺳﺖ. ﺑﻄﻮر ﮐﻠﯽ ﮐﺎرﺑﺮد ﻧﺎﻧﻮ ﮐﻼت ﭘﺘﺎﺳﯿﻢ در ﻏﻠﻈﺖ 35 ﻣﯿﻠﯽﮔﺮم در ﻟﯿﺘﺮ ﻣﻮﺟﺐ ﺗﻌﺪﯾﻞ اﺛﺮات ﻣﺨﺮب ﺗﻨﺶ ﺧﺸﮑﯽ روي ﺻﻔﺎت ﻣﻮرد اﻧﺪازهﮔﯿﺮي ﺷﺪه و ﻣﻮﺟﺐ اﻓﺰاﯾﺶ ﺳﺎزوﮐﺎرﻫﺎي دﻓﺎﻋﯽ ﮔﯿﺎه ﺑﺨﺼﻮص ﺑﻬﺒﻮد ﺳﯿﺴﺘﻢ ﻓﺘﻮﺳﻨﺘﺰي ﮔﯿﺎه ﮔﺮدﯾﺪ.

Since potassium plays an important role in the vital activities of the plant and is one of the inhibitors of the destructive effects of drought stress. In order to investigate the effect of potassium nano-chelated on some physiological and morphological characteristics of wheat in drought stress conditions, a factorial experiment in the form of a completely randomized basic design with three replications was performed in potted culture in the greenhouse of Mohaghegh Ardabili University. The factors include the first factor of drought stress at three levels of osmotic potential (0, -4 and -8 Bar), the second factor of wheat cultivars (Rasad and Gascogn) and the third factor including nano-chelated potassium (non-application of nano-chelated potassium, 35 and 65 mg /litr). Foliar application of nano-chelated potassium and drought stress with polyethylene glycol 6000 was applied simultaneously to plants in three to five leaves stage for five days and then samples were taken from control and treated samples. Foliar application of nano-chelated potassium increased the amount of photosynthetic pigments, leaf chlorophyll index, quantum yield, height of aerial and terrestrial organs, dry and wet weight of stems and roots. Drought stress reduced maximum fluorescence, quantum yield, chlorophyll a, chlorophyll b and total chlorophyll and the average stem length, internode length, leaf length, root length and also reduced wet and dry stem weight. Among the studied cultivars, the highest amount of measured physiological and morphological traits under drought condition was related to Gascogn cultivar. In other words, this cultivar showed a better response to drought stress under foliar application of potassium nano-chelated, which indicates greater tolerance of this cultivar to drought stress. In general, the application of nano-chelated potassium at a concentration of 35 mg / l moderated the damaging effects of drought stress and increased plant defense mechanisms, especially improving the plant's photosynthetic system.