Objective  Biological characteristics of the pathogen, Colletotrichum gloeosporioides, that infects the honey pomelos in Fujian were studied, and effective antifungal agents evaluated.

  Method  Effects of temperature, light, and pH on the mycelial growth, lethality, and sporulation of C. gloeosporioides were determined by crisscrossing and cell count methods. An in vitro toxicity test based on the mycelial growth rate was conducted to examine the efficacy of 4 fungicides against the anthracnose.

  Result  The optimum conditions for the pathogenic development included 25 ℃ for mycelial growth and 30 ℃ for sporulation at pH 7 and light exposure for sporulation. The mycelia died at 51 ℃ in 10 m. The indoor virulence test on the fungicides showed prochloraz with the lowest EC₅₀ at 0.0171 mg·L⁻¹, followed by difenoconazole at 0.0237 mg·L⁻¹, pyraclostrobin at 0.0345 mg·L⁻¹, and carbendazim at 0.2586 mg·L⁻¹.

  Conclusion  Temperature and pH exerted significant effects on the growth and sporulation of C. gloeosporioides. Limited effect was observed the mycelial growth by light exposure. Among the tested fungicides, prochloraz exhibited the greatest potential for controlling C. gloeosporioides.