- Bal, A.R. (1976). BioI. Plant., 18: 227-229.
- Bates, L.S. et a/. (1973). PI. Soil, 39: 205-208.
- Brown, L.M. and Hellebust, JA (1978). Can. J. Bot., 56: 676-679.
- Dubey, R.S. (1984). Oryza, 21: 213-217.
- Gloux, K. and Rudulier, D. Le (1989). Archives Microbiol., 151(2): 143-148.
- Khanna, S. and Rai, V,K. (1995). Indian J. Exp. BioI., 33: 766-770.
- Lauter, D.J. and Munns, D.N. (1986). PI. Soil, 95: 271-279.
- Lowry, O.H. etal. (1951). J. BioI. Chern., 193: 265-275.
- Miller, G.L (1959). Anal. Chern., 31: 426-428.
- Raggi, V. (1994). Physiol. Plant, 91: 427-434.
- Singh, M. and Singh, S. (1995). Indian J. PI. Physiol., 38(2): 109-113.
- Singh, G. etal. (1985). Experientia, 41: 40-41. .
- Thakur, P.S. and Rai, V.K. (1985). Biol. Plant, 27: 438-461.
- Trevelyan, W.E. and Harrison, J.S. (1952). Biochem. J.. 50: 299