Effect of herbicides on chlorophyll-a,β- caroten,phycocyanin and allophycocyanin content of Anabaena sp.

Pigments are frequently use in medicine,food,pharmacology,cosmetic,ink and textile preparations. cyanobacteria have a great potential for use as pigment producer,because they are easy to grow with simple nutrient requirements,unlike other microbial systems and additionally have a large number of pigment. cyanobacteria produce some pigments such as chlorophyll-a,carotenoids,phycobiliproteins. in addition,cyanobacteria can fix free atmospheric nitrogen. environmental conditions affect the cyanobacterial growth and pigment production. herbicides use commonly in paddy fields. because of this,herbicides can affect to non-target microorganisms such as cyanobacteria. in this study,production of some pigments by anabaena sp. go10 were studied using different herbicides in bg-11 medium. as herbicide,fenoxaprop-p-ethyl and cyhalofop-0butyl used in this study. in this work,different herbicide concentrations were applied on pigment production. initial fenoxaprop-p-ethyl concentrations (6,25 mg/l) stimulated chlorophyll-a,β- caroten,phycocyanin and allophycocyanin contents. but increasing herbicide concentrations suppressed to the all of pigment contents. the all of pigment contents of anabaena sp. go10 completely suppressed by 100 mg/l fenoxaprop-p-ethyl concentration. the other herbicide is cyhalofop-butyl. initial cyhalofop-butyl concentrations partly stimulated the pigment contents. but,the pigment contents of anabaena sp. go10 increased sharply by 25 mg/l cyhalofop-butyl concentrations. the all of pigment contents of anabaena sp. go10 completely repressed by 400 mg/l cyhalofop-butyl concentrations.