V. Rajesh Kannan, S. Sithara and S. Chandru
Hemoglobin is functioning as carriers and storage sources of oxygen in a wide variety of organisms including plants. Plant hemoglobins are found greatest abundance in the nitrogen fixing nodules of legumes. Mostly nodules are formed by bacteria like, Rhizobium or Bradyrhizobium by root colonization. After colonization, the bacteria begin to fix the nitrogen required by the plant. Commonly, the plant nodules are found certain tribes of tropical legumes such as Vigna and on some temperate legumes such as lotus. In this study four tropical legumes such as, Arachis hypogaea, Vigna radiata, Vigna mungo and Mymosa putika plant root nodules were selected and their protein content were analyzed, also 19 Rhizobium species isolated from selected plants root nodules. Among these nodules M. putika root nodules were showed maximum amount of protein (10.65 μg/ml) and Rhizobium GN3 had showed high total protein content (34.95 μg/ml). Leghaemoglobin for all root nodules and rhizobial isolates of respective root nodules were tested by Cyanmethemoglobin method. Among these nodules Leghaemoglobin concentration is high in the root nodules of A. hypogaea GN7, M. putika TN3, V. radiata GG3 and V. mungo BG2 showed that the absorbance value of 0.088, 0.044, 0.024 and 0.020. In conclude that those selected leguminous plants nodules Leghaemoglobin levels highly varied in quantitatively.
