Cicer arietinum) were all enhanced by the feather hydrolysate treatment. The treat ment improved soil fertility by increasing the C/N ratio and N, P, and K contents in the soil. The microbial activities in the soil were also boosted such that the inci dences of free nitrogen fixers and phosphate solubilizers were increased by 2- and 5.8-folds, respectively. Similarly, Arasu et al. (2009) investigated the plant growth promoting ability of two keratinolytic Bacillus strains, and found out that the feather hydrolysates obtained after their fermentations significantly increased the vigor index of rice seeds by 30%.