TABLE 1.

PCR primers used in this study

Primer	Target	Sequence (5′ to 3′)	Reference
NITRO821R	16S rDNA of unicellular cyanobacterial diazotrophs	CAA GCC ACA CCT AGT TTC	This study
CYA359F	16S rDNA of cyanobacteria	GGG GAA TYT TCC GCA ATG GG	19
OXY107F	16S rDNA of oxygenic phototrophs biased	GGA CGG GTG AGT AAC GCG GTG	31
OXY1313R	16S rDNA of oxygenic phototrophs biased	CTT CAY GYA GGC GAG TTG CAG C	31
CNF	nifH of cyanobacteria biased	CGT AGG TTG CGA CCC TAA GGC TGA	20
CNR	nifH of cyanobacteria biased	GCA TAC ATC GCC ATC ATT TCA CC	20