روﻧﺪ ﺗﻐﯿﯿﺮات ﻣﺘﺎﺑﻮﻟﯿﺖ ﻫﺎي ﮐﻠﺰا ﺗﺤﺖ ﺷﺮاﯾﻂ ﮐﻢ آﺑﯽ و ﺳﻄﻮح ﻣﺨﺘﻠﻒ ﻧﯿﺘﺮوژن

Changes in metabolites of canola under deficit water conditions and different nitrogen levels

ﭼﮑﯿﺪه ﺑﻪ ﻣﻨﻈﻮر ﺑﺮرﺳﯽ ﺗﺎﺛﯿﺮ ﺗﻨﺶ ﮐﻢ آﺑﯽ و ﻧﯿﺘﺮوژن ﺑﺮ ﺗﻐﯿﯿﺮات اﺳﯿﺪ آﻣﯿﻨﻪ ﻫﺎ و ﭘﺮوﻟﯿﻦ آزﻣﺎﯾﺶ ﮔﻠﺨﺎﻧﻪ اي ﺑﺼﻮرت ﻓﺎﮐﺘﻮرﯾﻞ در ﻗﺎﻟﺐ ﻃﺮح ﮐﺎﻣﻼ ﺗﺼﺎدﻓﯽ ﺑﺎ ﺳﻪ ﺗﮑﺮار ﺑﻪ ﻣﻮرد اﺟﺮا ﮔﺬاﺷﺘﻪ ﺷﺪ. ﺗﯿﻤﺎرﻫﺎي آزﻣﺎﯾﺶ ﺷﺎﻣﻞ ﺗﻨﺶ ﺧﺸﮑﯽ در ﺳﻪ ﺳﻄﺢ )%30، %50 و 70% ﻇﺮﻓﯿﺖ زراﻋﯽ( و ﺳﻄﻮح ﻣﺨﺘﻠﻒ ﻧﯿﺘﺮوژن در ﭘﻨﺞ ﺳﻄﺢ )ﺷﺎﻫﺪ ﺑﺮ اﺳﺎس آزﻣﻮن ﺧﺎك، 25% ﮐﻤﺘﺮ از ﻣﯿﺰان ﺗﻮﺻﯿﻪ ﺷﺪه، 50% ﮐﻤﺘﺮ از ﻣﯿﺰان ﺗﻮﺻﯿﻪ ﺷﺪه، 25% ﺑﯿﺸﺘﺮ از ﻣﯿﺰان ﺗﻮﺻﯿﻪ ﺷﺪه و 50% ﺑﯿﺸﺘﺮ از ﻣﯿﺰان ﺗﻮﺻﯿﻪ ﺷﺪه( ﺑﻮد. ﻧﺘﺎﯾﺞ ﺗﺠﺰﯾﻪ وارﯾﺎﻧﺲ ﻧﺸﺎن داد ﮐﻪ اﺛﺮ ﺳﺎده ﺗﻨﺶ، ﻧﯿﺘﺮوژن و ﻫﻤﭽﻨﯿﻦ اﺛﺮ ﻣﺘﻘﺎﺑﻞ ﺗﻨﺶ و ﻧﯿﺘﺮوژن در ﺗﻤﺎم ﻣﺮاﺣﻞ ﻧﻤﻮﻧﻪﺑﺮداري )ﻣﺮﺣﻠﻪ ﭼﻬﺎر ﺗﺎ ﺷﺶ ﺑﺮﮔﯽ و ﻫﺸﺖ ﺗﺎ ده ﺑﺮﮔﯽ( ﺑﺮ ﻣﯿﺰان ﭘﺮوﺗﺌﯿﻦ ﻣﺤﻠﻮل ﮐﻞ، اﺳﯿﺪ آﻣﯿﻨﻪﻫﺎي ﻟﯿﺰﯾﻦ، ﻣﺘﯿﻮﻧﯿﻦ و ﭘﺮوﻟﯿﻦ ﻣﻌﻨﯽدار ﺑﻮد. ﺣﺪاﮐﺜﺮ ﭘﺮوﺗﺌﯿﻦ ﻣﺤﻠﻮل ﮐﻞ )28/63 ﻣﯿﻠﯽﮔﺮم در ﻫﺮ ﮔﺮم وزن ﺗﺮ( در ﻣﺮﺣﻠﻪ ﻫﺸﺖ ﺗﺎ ده ﺑﺮﮔﯽ ﺑﻪ ﺗﯿﻤﺎر ﺗﻨﺶ ﮐﻢ آﺑﯽ ﺷﺪﯾﺪ )30 % = FC و ﮐﺎرﺑﺮد 0/09 ﮔﺮم ﻧﯿﺘﺮوژن در ﻫﺮ ﮐﯿﻠﻮﮔﺮم ﺧﺎك )ﺷﺎﻫﺪ( اﺧﺘﺼﺎص ﯾﺎﻓﺖ. ﻣﯿﺰان ﻟﯿﺰﯾﻦ در ﻣﺮﺣﻠﻪ ﻫﺸﺖ ﺗﺎ ده ﺑﺮﮔﯽ در ﻣﻘﺎﯾﺴﻪ ﺑﺎ ﻣﺮﺣﻠﻪ ﭼﻬﺎر ﺗﺎ ﺷﺶ ﺑﺮﮔﯽ ﮐﺎﻫﺶ ﯾﺎﻓﺖ، اﻣﺎ ﺑﺮ ﺗﺠﻤﻊ ﻣﺘﯿﻮﻧﯿﻦ اﻓﺰوده ﺷﺪ.

To evaluate the effects of deficit water and nitrogen on changing of amino acids and proline, a factorial experiment was conducted in a completely randomized design with three replications at the experimental greenhouse. Treatments included three levels of drought stress (30%, 50%, and 70% of FC) and five levels of nitrogen (control, based on soil test results; 25% less than the recommended level; 50% less than the recommended level; 25% more than the recommended level; and 50% more than the recommended level). Anova results showed that deficit water, nitrogen and their interaction significantly affected total protein, lysine, methionine and proline at various stages of growth. The total soluble protein content increased with the advancement of plant growth. The highest total soluble protein (28.63 mg.g-1 fresh weight) was observed at 8-10 leaf stage under severe water stress conditions (30% FC) and the application of 0.09 g nitrogen per Kg of soil (control). Changes in lysine and methionine amino acids were different over the growth period, so that the lysine content was decreased at 8-10 leaf stage compared to that of 4-6 leaf stage while the methionine was accumulated over the same period of time.