Using oligoagar to improve the survival of Neoporphyra haitanensis conchocelis infected by Vibrio mediterranei 117-T6

Neoporphyra haitanensis is a vital economic seaweed in China. As an infectious disease with a high incidence in the conchocelis sporeling culture of Porphyra, yellow spot disease (YSD) seriously affects the industrial development of seaweed cultivation. In the present study, we analyzed the protective effect of oligoagar (OA) on YSD caused by Vibrio mediterranei 117-T6 (Vm 117-T6). The experiment was conducted under the standard culture conditions of N. haitanensis conchocelis. The results showed that OA treatment (0.1 g L−1 OA treatment for 1 h and performed twice with a 48 h interval) could significantly improve the survival of N. haitanensis conchocelis infected by Vm 117-T6 (P < 0.05). Furthermore, OA treatment increased the physiological and biochemical indexes, such as superoxide dismutase (SOD), phycobiliprotein and photosynthetic pigment content of Porphyra. Therefore, OA treatment has good application potential for preventing YSD caused by V. mediterranei 117-T6.