پديد آورندگان :
دولت كردستاني، مجتبي دانشگاه هرمزگان - دانشكده علوم كشاورزي و منابع طبيعي - گروه مرتع و آبخيزداري , تقوايي، منصور دانشگاه شيراز - گروه زراعت و اصلاح نباتات - دانشكده كشاورزي , برخوري، سعيد دانشگاه هرمزگان - دانشكده علوم كشاورزي و منابع طبيعي - گروه مرتع و آبخيزداري
كليدواژه :
آنتي اكسيدان , پرولين , پلي آمين , خشكي , كلروفيل
چكيده فارسي :
ﺑﺎ ﺗﻮﺟﻪ ﺑﻪ اﻫﻤﯿﺖ درﺧﺘﭽﻪ اﺳﺘﺒﺮق در اﺣﯿﺎي ﻣﻨﺎﻃﻖ ﺧﺸﮏ و ﺑﯿﺎﺑﺎﻧﯽ و ﻗﺮارﮔﯿﺮي ﮐﺸﻮر اﯾﺮان در ﻣﻨﺎﻃﻖ ﮐﻢ ﺑﺎران و ﺧﺸﮏ ﺗﺎ ﮐﻨﻮن ﭘﮋوﻫﺶ ﻫﺎي ﮐﺎﻓﯽ ﺑﺮاي ﺷﻨﺎﺧﺖ وﯾﮋﮔﯽ ﻫﺎي ﻣﻮرﻓﻮﻓﯿﺰﯾﻮﻟﻮژﯾـﮏ درﺧﺘﭽﻪ اﺳﺘﺒﺮق در ﺷﺮاﯾﻂ ﺗﻨﺶ ﺧﺸﮑﯽ و ﺗﻌﯿﯿﻦ ﺟﺎﯾﮕﺎه ﭘﻮﺗﺮﺳﯿﻦ در ﮐﺎﻫﺶ اﺛﺮات ﻣﺨﺮب ﺧﺸﮑﯽ اﻧﺠﺎم ﻧﺸﺪه اﺳﺖ. ﺑـﻪ ﻫﻤـﯿﻦ ﻣﻨﻈﻮر ﭘﮋوﻫﺸﯽ ﺑﺎ ﻫﺪف اﺛﺮ ﭘﻮﺗﺮﺳﯿﻦ ﺑﺮ ﺑﺮﺧﯽ وﯾﮋﮔﯽ ﻫﺎي ﻣﻮرﻓﻮﻟﻮژﯾﮑﯽ و ﻓﯿﺰﯾﻮﻟﻮژﯾﮑﯽ ﻧﻬﺎل ﻫﺎي اﺳﺘﺒﺮق در ﺷﺮاﯾﻂ ﺗﻨﺶ ﺧﺸﮑﯽ، ﺑﻪ ﺻﻮرت ﻃﺮح ﮐﺮت ﻫﺎي ﺧﺮد ﺷﺪه در ﻗﺎﻟﺐ ﻃﺮح ﺑﻠﻮك ﻫﺎي ﮐﺎﻣﻞ ﺗﺼﺎدﻓﯽ ﺑـﺎ ﭼﻬـﺎر ﺗﮑﺮار در ﻣﺰرﻋﻪ ﺗﺤﻘﯿﻘﺎﺗﯽ داﻧﺸﮕﺎه ﻫﺮﻣﺰﮔﺎن اﻧﺠﺎم ﺷﺪ. ﻓﺎﮐﺘﻮر اﺻﻠﯽ ﺷﺎﻣﻞ ﭘﻨﺞ ﺳﻄﺢ (1 (ﺷـﺎﻫﺪ)، 3، 6، 9 و 12 روز دور آﺑﯿﺎري) و ﺗﯿﻤﺎر ﭘﻮﺗﺮﺳﯿﻦ ﺑﻪ ﺻﻮرت ﻣﺤﻠﻮلﭘﺎﺷﯽ ﺑﺮﮔﯽ 3 ﻧﻮﺑﺖ ﺑﻪ ﻓﺎﺻﻠﻪ 20 روز ﯾﮑﺒﺎر در ﭘـﻨﺞ ﺳﻄﺢ (0، 0/5، 1، 1/5 و 2 ﻣﯿﻠﯽ ﻣﻮﻻر) در ﭘﻼت ﻫﺎي ﻓﺮﻋﯽ ﻗﺮار ﮔﺮﻓﺖ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ اﻓﺰاﯾﺶ دور آﺑﯿﺎري ﺗﺎ 12 روز ﺳﺒﺐ ﮐﺎﻫﺶ ﺳﻄﺢ ﺑﺮگ، وزن ﺗﺮ و ﺧﺸﮏ اﻧﺪام ﻫﻮاﯾﯽ، وزن ﺗﺮ و ﺧﺸﮏ رﯾﺸﻪ و ﻣﺤﺘﻮاي ﮐﻠﺮوﻓﯿﻞ ﺷﺪ. ﻫﻤﭽﻨﯿﻦ اﻓﺰاﯾﺶ دور آﺑﯿﺎري ﺗﺎ 12 روز ﺳﺒﺐ اﻓﺰاﯾﺶ ﻣﺤﺘﻮاي ﭘﺮوﻟﯿﻦ و ﻓﻌﺎﻟﯿﺖ آﻧـﺰﯾﻢ ﻫـﺎي ﺳﻮﭘﺮاﮐﺴـﯿﺪ دﯾﺴﻤﻮﺗﺎز، ﮐﺎﺗﺎﻻز، ﭘﺮاﮐﺴﯿﺪاز و آﺳﮑﻮرﺑﺎت ﭘﺮاﮐﺴﯿﺪاز ﮔﺮدﯾﺪ. اﻓﺰاﯾﺶ در ﻏﻠﻈﺖ ﭘﻮﺗﺮﺳﯿﻦ ﺑﻪ ﻃﻮر ﻣﻌﻨـﯽ داري ﺳﺒﺐ اﻓﺰاﯾﺶ ﺳﻄﺢ ﺑﺮگ، وزن ﺗﺮ و ﺧﺸﮏ اﻧﺪام ﻫﻮاﯾﯽ و رﯾﺸﻪ، ﻣﺤﺘﻮاي ﮐﻠﺮوﻓﯿﻞ، ﻣﺤﺘﻮاي ﭘﺮوﻟﯿﻦ و ﻓﻌﺎﻟﯿﺖ آﻧﺰﯾﻢ ﻫﺎي ﺳﻮﭘﺮاﮐﺴﯿﺪ دﯾﺴﻤﻮﺗﺎز، ﭘﺮاﮐﺴﯿﺪاز و آﺳﮑﻮرﺑﺎت ﭘﺮاﮐﺴﯿﺪاز در ﺑﺮگ ﻫﺎ ﮔﺮدﯾﺪ. ﺑﻬﺘﺮﯾﻦ ﺗﯿﻤﺎر ﭘﻮﺗﺮﺳﯿﻦ ﺟﻬﺖ ﮐﺎﻫﺶ اﺛﺮات ﻣﺨﺮب ﺧﺸﮑﯽ در ﻏﻠﻈﺖ 2 ﻣﯿﻠﯽ ﻣﻮﻻر ﻣﺸﺎﻫﺪه ﺷﺪ. ﺑﺎ ﺗﻮﺟﻪ ﺑـﻪ ﻧﺘـﺎﯾﺞ ﺑـﻪ دﺳـﺖ آﻣـﺪه اﺳﺘﻔﺎده از ﭘﻮﺗﺮﺳﯿﻦ ﺟﻬﺖ اﺳﺘﻘﺮار اﯾﻦ ﮔﯿﺎه در ﺷﺮاﯾﻂ ﺧﺸﮑﯽ ﻗﺎﺑﻞ ﺗﻮﺻﯿﻪ ﻣﯽ ﺑﺎﺷﺪ.
چكيده لاتين :
Given the importance of Giant Milkweed shrub in reclamation of deserts and arid regions, and position of Iran in low rainfall and arid areas, so far enough research has not been done to understand the morpho-physiological properties of the Giant Milkweed shrub under drought stress conditions and to determine the status of putrescine in reducing the devastating effects of drought. For this purpose, a field experiment was conducted in a split plot randomized complete block design with four replications to determine the effect of putrescine on some morphological and physiological characteristics of Giant Milkweed seedlings under drought stress conditions in Research Farm of the University of Hormozgan. The main factor included five levels of irrigation (1 (control), 3, 6, 9 and 12 days irrigation intervals) and putrescine treatment by foliar sprays at 3 steps every 20 days at five levels (0, 0.5, 1, 1.5, 2 mM) in sub plots. Results showed that an increase in irrigation interval up to 12 days reduced leaf area, fresh and dry weight of shoots, fresh and dry weight of roots, and chlorophyll content. Also, increased irrigation interval up to 12 days increased proline content, superoxide dismutase, catalase, ascorbate peroxidase, and peroxidase enzymes activities. Increase in the concentration of putrescine, led to a significant increase in leaf area, fresh and dry weights of shoots and roots, chlorophyll content, proline content, and superoxide dismutase, peroxidase, and ascorbate peroxidase enzymes activities in the leaves. The best putrescine treatment to reduce the devastating effects of drought was observed at concentration of 2 mM. According to the results obtained, the use of putrescine to establish the plant in dry conditions is recommended.
