The invention discloses a primer and a method for quantitatively monitoring the
biomass of
sargassum hemiphyllum based on an
environmental DNA technology, and belongs to the technical field of
molecular ecology. The primer probe group comprises an upstream primer, a downstream primer and a fluorescent probe which are specifically targeted to the
sargassum hemiphyllum mitochondria COX1
gene, and the sequence is shown as SEQ ID NO.1-3. The kit comprises the primer probe group, a qPCR (quantitative
polymerase chain reaction) premixed solution,
nuclease-
free water and a
sargassum hemiphyllum
plasmid positive control. The method comprises the following steps: collecting a
water sample, enriching eDNA, performing qPCR detection by using the primer probe group after extraction and purification, and realizing qualitative detection and quantitative evaluation of sargassum hemiphyllum through a Cq value or a
standard curve. The method disclosed by the invention has the advantages of high sensitivity, strong specificity, no damage to the environment and target organisms, capability of realizing large-scale rapid general survey and the like, and is suitable for early warning of gulfweed blooms, investigation of
population distribution and evaluation of ecological influence.