اثرات نيترات پتاسيم بر خصوصيات جوانه زني و رشد اوليه آفتابگردان تحت تنش هاي شوري و خشكي

Effects of Potassium Nitrate on Germination Characteristics and Early Growth of Sunflower under Salinity and Drought Stresses

ﺑﻪ ﻣﻨﻈﻮر ﻣﻄﺎﻟﻌﻪ ﺗﺎﺛﯿﺮ ﭘﺮاﯾﻤﯿﻨﮓ ﺑﺬور آﻓﺘﺎﺑﮕﺮدان ﺑﺎ ﻧﯿﺘﺮات ﭘﺘﺎﺳﯿﻢ ﺑﺮ ﺟﻮاﻧﻪ زﻧﯽ آنﻫﺎ در ﺷﺮاﯾﻂ ﺗﻨﺶﻫﺎي ﺷﻮري و ﺧﺸﮑﯽ آزﻣﺎﯾﺸﺎﺗﯽ ﺻﻮرت ﭘﺬﯾﺮﻓﺖ. ﻣﺤﻞ اﻧﺠﺎم آزﻣﺎﯾﺶﻫﺎ آزﻣﺎﯾﺸﮕﺎه ﻓﯿﺰﯾﻮﻟﻮژي داﻧﺸﮑﺪه ﮐﺸﺎورزي داﻧﺸﮕﺎه ﺑﻮﻋﻠﯽ ﺳﯿﻨﺎ ﻫﻤﺪان ﺑﻮد. آزﻣﺎﯾﺶ ﺷﻮري ﺑﻪ ﺻﻮرت ﻓﺎﮐﺘﻮرﯾﻞ در ﻗﺎﻟﺐ ﻃﺮح ﮐﺎﻣﻼ ﺗﺼﺎدﻓﯽ ﺑﺎ دو ﻓﺎﮐﺘﻮر ﭘﺮاﯾﻤﯿﻨﮓ ﺑﺬر و ﺗﻨﺶ ﺷﻮري و در ﺳﻪ ﺗﮑﺮار اﻧﺠﺎم ﺷﺪ. ﺳﻄﻮح ﭘﺮاﯾﻢ ﺷﺎﻣﻞ ﺷﺎﻫﺪ و ﺗﯿﻤﺎر ﺑﺬر ﺑﺎ ﻧﯿﺘﺮات ﭘﺘﺎﺳﯿﻢ و ﺳﻄﻮح ﺷﻮري ﺷﺎﻣﻞ 6 ،-4 ،-2 ،0- و 8- ﺑﺎر ﺑﻮد. آزﻣﺎﯾﺶ ﺧﺸﮑﯽ ﻧﯿﺰ ﺑﻪ ﺻﻮرت ﻓﺎﮐﺘﻮرﯾﻞ در ﻗﺎﻟﺐ ﻃﺮح ﮐﺎﻣﻼ ﺗﺼﺎدﻓﯽ ﺑﺎ دو ﻓﺎﮐﺘﻮر ﭘﺮاﯾﻤﯿﻨﮓ ﺑﺬر و ﺳﻄﻮح ﺧﺸﮑﯽ و در ﺳﻪ ﺗﮑﺮار اﻧﺠﺎم ﺷﺪ. ﺗﯿﻤﺎرﻫﺎي آزﻣﺎﯾﺶ ﺧﺸﮑﯽ ﺷﺎﻣﻞ ﭘﺮاﯾﻢ ﺑﺬور در دو ﺳﻄﺢ ﺷﺎﻫﺪ )ﺑﺪون ﭘﺮاﯾﻢ( و ﭘﺮاﯾﻢ ﺑﺎ ﻧﯿﺘﺮات ﭘﺘﺎﺳﯿﻢ و ﺗﯿﻤﺎر ﺗﻨﺶ ﺧﺸﮑﯽ در ﭘﻨﺞ ﺳﻄﺢ )6 ،-4 ،-2 ،0- و 8- ﺑﺎر ( ﺑﻮدﻧﺪ. ﻧﺘﺎﯾﺞ دو آزﻣﺎﯾﺶ ﻧﺸﺎن داد ﮐﻪ ﺑﺎ اﻓﺰاﯾﺶ ﺗﻨﺶ ﺷﻮري و ﺧﺸﮑﯽ، ﻣﻮﻟﻔﻪ ﻫﺎي ﺟﻮاﻧﻪ زﻧﯽ ﺷﺎﻣﻞ درﺻﺪ ﺟﻮاﻧﻪ زﻧﯽ، ﺳﺮﻋﺖ ﺟﻮاﻧﻪ زﻧﯽ و وزن ﺧﺸﮏ ﮔﯿﺎﻫﭽﻪ ﮐﺎﻫﺶ ﯾﺎﻓﺘﻨﺪ. وﻟﯽ، ﻣﯿﺰان اﯾﻦ ﮐﺎﻫﺶ ﺑﺮاي ﺑﺬرﻫﺎي ﺗﯿﻤﺎر ﺷﺪه ﺑﺎ ﻧﯿﺘﺮات ﭘﺘﺎﺳﯿﻢ ﮐﻤﺘﺮ ﺑﻮد. در ﮐﻠﯿﻪ ﺳﻄﻮح ﺷﻮري و ﺧﺸﮑﯽ ﺑﺬرﻫﺎي ﺗﯿﻤﺎر ﺷﺪه ﻧﺴﺒﺖ ﺑﻪ ﺑﺬور ﺷﺎﻫﺪ داراي ﻋﻤﻠﮑﺮد ﺑﻬﺘﺮي از ﻟﺤﺎظ ﺻﻔﺎت ﻣﻮرد ﺑﺮرﺳﯽ ﺑﻮدﻧﺪ. ﺑﻪ ﻃﻮر ﮐﻠﯽ ﻣﯽ ﺗﻮان ﻧﺘﯿﺠﻪ ﮔﺮﻓﺖ ﮐﻪ ﭘﺮاﯾﻤﯿﻨﮓ ﺑﺬور آﻓﺘﺎﺑﮕﺮدان ﺑﺎ ﻧﯿﺘﺮات ﭘﺘﺎﺳﯿﻢ ﺗﺎ ﺣﺪودي ﺑﺎﻋﺚ ﺑﻬﺒﻮد ﻣﻮﻟﻔﻪ ﻫﺎي ﺟﻮاﻧﻪ زﻧﯽ در ﺷﺮاﯾﻂ ﺗﻨﺶﻫﺎي ﺷﻮري و ﺧﺸﮑﯽ ﮔﺮدﯾﺪ و ﻣﯽ ﺗﻮاﻧﺪ ﻣﻘﺎوﻣﺖ ﮔﯿﺎه آﻓﺘﺎﺑﮕﺮدان را در ﻣﻘﺎﺑﻞ اﯾﻦ ﺗﻨﺶ ﻫﺎ در ﻣﺮﺣﻠﻪ ﺟﻮاﻧﻪ زﻧﯽ اﻓﺰاﯾﺶ دﻫﺪ.

In order to study the effect of priming sunflower seeds by potassium nitrate on germination seeds was conducted experiments in salinity and drought conditions. Location of experiments was Physiology Laboratory, Faculty of Agriculture, Bu Ali Sina University, Hamedan. Salinity experiment was conducted as factorial based on randomized complete block design (RCBD) with two factor of seed priming and salinity and three replications. Priming levels included control and seed treatment by potassium nitrate and salinity levels included 0, -2, -4, -6, and -8 bar. Also, drought experiment was conducted as factorial based on randomized complete block design (RCBD) with two factor of seed priming and drought levels in three replications. Drought experiment treatment included control (non-priming) and priming by potassium nitrate and drought stress treatment were five levels (0, -2, -4, -6, and -8 bar). The results of two experiments showed that increasing in salinity and drought stress, decreased germination components including germination, germination rate and dry weight of seedlings. However, this reduction was lower for seeds that were treated by potassium nitrate. In terms of the studied traits, at all of the levels of salinity and drought treatment seeds were better than control seeds. In general, it can be concluded that the priming of sunflower seeds by potassium nitrate improved the germination components under salinity and drought stress and can increase sunflower plant resistant against these stresses in the germination stage.