Department of Botany, Banaras Hindu University, Varanasi-221005
* Present address: Department of Genetics and Plant Breeding, Banaras Hindu University, Varanasi-221005.
Heterocyst production in Anabaena variabilis is repressible by fixed inorganic nitrogen sources. Derepression of heterocyst differentiation occurs in nitrogen-free medium and the alga grows well at the expense of N2. All attempts to grow the alga heterotrophieally failed.
