8448

7829

كارشناسي ارشد

خاك شناسي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي

1392

سيزده،86ص.: مصور،جدول،نودار

ص.ع.به فارسي و انگليسي

اميرحسين خوشگفتارمنش

فرشيد نوربخش

5/11/92

حسين شريعتمداري، بهروز مصطفي زاده

مهندسي كشاورزي

ID7829

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Abstract Nickel Ni is a structural component of urease enzyme and it is required for nitrogen metabolism in higher plants Deficiency of Ni results in reduction of urease activity and probably other enzymes responsible for nitrate reduction Little is known regarding the growth and physiological response of onion plant to Ni nutrition In this research study we investigated the effects of Ni on nitrogen metabolism and growth of two onion cultivars Allium cepa L cvs Dorrcheh and Cebolla Valenciana supplied with ammonium nitrate or urea as nitrogen source Three levels of nickel 0 25 and 50 M were used in the form of NiCl 2 or Ni histidine Ni His 2 complex Results obtained from the present study showed that in plants supplied with urea as sole nitrogen source aaddition of Ni in the forms of NiCl2 or Ni His 2 complex resulted in increase of urease activity and decrease of bulb urea concentration Addition of Ni into the nutrient solution regardless of its applied source stimulated hydrolysis of urea and production of NH 4 and resulted in higher concentration of the total amino acids and nitrogen in onion bulbs The efficiency of Ni His 2 complex in improving Ni uptake and increasing activity of urease and glutamine synthetase GS two enzymes involved in urea metabolism was greater than NiCl2 Results also indicated that Ni nutrition resulted in enhancement of onion bulb yield probably due to the positive effect of Ni on improvement of nitrogen metabolism in plans grown at the nutrient solutions containing urea For onion plants supplied with ammonium nitrate as nitrogen source addition of Ni into the nutrient solution positively affected nitrate metabolism and resulted in lower accumulation of nitrate in the bulbs Addition of Ni into the nutrient solution regardless of its source improved bulb yield of onion cultivars via stimulating reduction of nitrate and increasing concentrations of NH4 and total nitrogen In nutrient solution containing ammonium nitrate the efficiency of Ni His 2 complex in improving Ni uptake increasing activity of nitrate reductase NR and glutamine synthetase GS increasing total nitrogen concentration and reduction of nitrate accumulation was greater than NiCl 2 According to the results obtained from the present study Ni nutrition particularly in the form of Ni His 2 complex as a modern Ni fertilizer source in the nutrient solution decreased urea and nitrate concentration in onion bulb and thereby increased yield and health quality of onion Key words Nickel Histidine Onion Nitrogen metabolism Urease Nitrate reductase NR Glutamine synthetase GS PDF created with pdfFactory trial version www pdffactory com

اميرحسين خوشگفتارمنش

فرشيد نوربخش

حسين شريعتمداري، بهروز مصطفي زاده