Effect of certain herbicides on survival, growth, and nitrogen fixation of blue-green alga Anabaena doliolum Bharadwaja.

Growth and fixation of nitrogen were retarded in Anabaena doliolum when grown on elemental nitrogen in presence of four different herbicides. The alga was found to be intolerant to these chemicals under nitrogen fixing conditions even in low concentrations. An inhibition of photosynthesis has been regarded as the main basis of herbicidal activity besides other interactions.