Determination of Herbicide Resistance in Aquatic Cyanobacteria by Probit Analysis

  • Hale KOKSOY
  • Belma ASLIM
Keywords: Herbicide, lethal concentration and probit analysis


Cyanobacteria are a group of bacteria that obtain their energy by photosynthesis and play a significant role in the breakdown of herbicides in nature. In this study, experiments were performed for a period of 15 days with 12 cyanobacteria obtained from different aquatic environments and three herbicides commonly used in agriculture {2,4 Dichlorophenoxyacetic acid (2,4-D), Trifluralin and Linuron}. The herbicides were pipetted at certain concentrations into BG11 broth. The herbicide resistance of the 12 cyanobacteria was determined by using Chlorophyll-a measurement, rate of growth assessment, the probit analysis and the results of the lethal concentration test (LC10;50). According to the LC10 values at day 15; the Synechocystis sp. strain number 6 in the 2,4-D environment, the Synechococcus sp. strain number 41 in the Trifluralin environment, and the Chroococcus sp. strain number 4 in the Linuron environment, were determined to be resistant to the concentrations of herbicide. According to the day 15 values, the Synechocystis sp. strain number 6 was determined to be resistant to three different herbicide concentrations in the 2,4-D, Trifluralin and Linuron environments. Since it is a study that contributes to the protection of the environment, we intended for this study to set a new precedent for other studies.