African Journal of Biotechnology Vol. 4 (7), pp. 667-671, July 2005          
ISSN 1684–5315 © 2005 Academic Journals

Full Length Research Paper

Response of Glycine max in relation to nitrogen fixation as influenced by fungicide seed treatment

Anupama Bikrol, Nidhi Saxena and Kiran Singh*

Laboratory of Bioenergetics, Department of Microbiology, Barkatullah University, Bhopal-462026, India.

*Corresponding Author Tel: +91 0755 2677729, Fax: +91 0755 2677729. E-mail: kirans_edu@yahoo.co.in.

Accepted 8 March, 2005

Glycine max – Rhizobium interaction is a well known symbiotic association occurring in nature and responsible for biological nitrogen fixation. Thiram a well-known fungicide has been in practice as seed dressing in order to prevent fungal colonization. In the present study the effect of various thiram concentrations is investigated. Thiram concentration beyond 500 μg/ml was observed to be highly toxic with respect to plant growth factors and rhizobial infection to the G. max. The nodulation, nodule dry weight, nitrogenase activity were observed to be maximum at 100 μg/ml of thiram. The study is useful in determining the threshold concentration of fungicide for soybean seed dressing for effective nitrogen fixation and crop yield.

Key words: Ascorbic acid, chlorophyll content, Glycine max, nodulation, nodule dry weight, nitrogenase activity, protein content, thiram.