Punjab Agricultural University, Ludhiana, Punjab
*Present address: Department of Soils, Rajendra Agricultural University, Pusa, Samastipur, Bihar
The mean molecular weights of soil humic acid, fulvic acid and poultry litter humic acid and fulvic acid were approximated from their elution volume and void volume on sephadex gels as 6918, 906, 4207, 509, respectively. Elution pattern indicated heterogeneity of these humic substances. A significant correlation between Kd and E4/E6 colour ratios of fulvic acid fractions was noted.
Sephadex gel, E4/E6, molecular weight, elution pattern
