Abstract:
Objective To study the effects of temperature and host on Cacopsylla citrisuga growth and development.
Method C. citrisuga was parasitized on healthy or Candidatus Liberibacter asiaticus-infected Citrus limon in the incubators under simulative natural environment. The developmental periods, survival rates of different life stages, preoviposition period and fecundity of C. citrisuga were analyzed and compared. Adult survival rates were compared for C. citrisuga parasitized on C. limon, Murraya exotica and Citrus sunki under 15, 20 and 25℃.
Result Under 15 ℃, 70% relative humidity and on healthy C. limon, the mean duration of C. citrisuga egg was 9.38 days, the durations from 1st to 5th instar nymph were 8.80, 6.66, 6.00, 6.76 and 5.94 days respectively, the preoviposition period was 16.2 days, the total duration of generation was 59.74 days and the survival rate of generation was 28.34%. For C. citrisuga parasitized on Ca. L. asiaticus-infected C. limon, the durations of 2nd instar, 4th instar and total nymph stages significantly decreased, the preoviposition period significantly increased, and the survival rates of 4th instar, total nymph stages and generational period significantly decreased compared to those on healthy lemon. There was no significant difference in fecundity when the same origin psyllid females were laying eggs on healthy and infected C. limon, but the fecundity of the subsequent generation females emerged from healthy C. limon was significantly higher compared to those from infected C. limon. The survival rate of C. citrisuga adults was the highest on C. limon comparing three hosts under the same temperature, and was the highest under 15℃ comparing different temperatures when reared on the same host plant species. There were 81.67% adults survived after 20 days of being parasitized on C. limon under 15 ℃. The nymph developed faster when parasitized on Ca. L. asiaticus-infected C. limon, but the pathogen negatively influenced the survival and reproduction of C. citrisuga.
Conclusion C. citrisuga can accomplish the whole generation with high survival rate under the above conditions, which can be applied to breed C. citrisuga indoor, and can be used for other studies related to C. citrisuga growth and Huanglongbing mechanisms.