Abstract
A hydroponic study was conducted to investigate the nutritional role of calcium on growth and ionic concentration of Brassica (B. napus cv. Dunkled) at four levels of NaCI salinity (0, 30, 60 and 90 mM) and two calcium levels (4 and 8 mM) as calcium sulfate. The salinity levels were imposed a week after transplantation by incremental addition of 30 mM NaCI on alternate days while calcium levels were maintained two days after transplantation. Significant reduction of 33 and 42 % in shoot dry matter yield was noticed at 60 and 90 mM NaCI levels as compared to control (harvest I). However, 24, 38 and 5 % increase in shoot dry matter yield at 0, 60 and 90 mM NaCI levels were recorded when plants were fed with elevated level of calcium supply (8mM) as compared to 4 mM Ca (Harvest I). With increasing concentration of NaCI in root medium, 20 and 32% reduction in root dry matter yield at 60 and 90 mM NaCI levels. Elevated supply of calcium increased 27 and 15% root dry matter yield at 0 and 30 mM NaCI levels. However, elevated supply of calcium did not improve the root dry matter yield at 60 and 90 mM NaCI levels. Plant shoot exhibited more sodium concentration with the increasing sodium chloride concentration. However, the presence of elevated calcium supply resulted in 44% less sodium contents in plant shoot as compared to 4 mM Ca supply. Elevated level of calcium application to plants increased 33% calcium in plant tissues as compared to 4 mM calcium supply. Significant negative correlation (r = -0.85) between dry matter and sodium contents in shoot at 4 mM calcium supply to root medium. However, significant positive correlation (r=0.97) between dry matter yield and K concentration in plants at 4 mM calcium supply. Keywords: Brassica napus, calcium, sodium, saline conditiuon
