HORTICULTURAL ENTOMOLOGY Biology of Diaphorina citri (Homoptera: Psyllidae) on Four Host Plants

The biology of the citrus psyllid Diaphorina citri Kuwayama was studied at 258C on four commonly grown citrus and related plants [rough lemon, Citrus jambhiri Lush; sour orange, C. aurantiumL.; grapefruit,C.paradisiMacfadyen; andorange jessamine,Murrayapaniculata(L.) Jack] in the laboratory. The biological characteristics of each life stage are described. The average egg incubation periods on orange jessamine, grapefruit, rough lemon, and sour orange varied very little (4.1Ð4.2 d). The average nymphal developmental periods on these four host plants were essentially the same except the Þfth stadium. Survival of immatures on orange jessamine, grapefruit, rough lemon, and sour orange was 75.4, 84.6, 78.3, and 68.6%, respectively. Female adults lived an average of 39.7, 39.7, 47.6, and 43.7 d on these respective host plants. The average number of eggs laid per female on grapefruit (858 eggs) was signiÞcantly more than those on other hosts (P , 0.05). The intrinsic rate of natural increase (rm) for D. citri on grapefruit was highest. Jackknife estimates of rm varied from 0.188 on grapefruit to 0.162 on orange jessamine and rough lemon. The mean population generation time on these hosts ranged from 31.6 to 34.1 d. The continuous ßushes produced by orange jessamine could play an important role in maintaining high populations of this vector when the new ßushes are not available in the commercial citrus groves.