Search Filter
- Publications
- Abstract of Theses and Dissertations
- Database
- Population Ecology of Leucaena Psyllid, Ueteropsylla Cubana Crawford...
Population Ecology of Leucaena Psyllid, Ueteropsylla Cubana Crawford (Homoptera: Psyllidae) in the Northern Highland Area of Thailand
Abstract:
A study of the population ecology of a leucaena psyllid, Heteropsylla cubana Crawford, was carried out at Maejo, Chomtong, and Maesa-mai ecological modules in Chiangmai, Thailand, between December 1990 and December 1991. The sampling method used for the population study of H. cubana was modified from Elder and Mayer ( 1991 ). H cubana eggs, nymphs, and adults congregated on the terminaI shoots that spread over the canopy of leucaena. Populations of H. cubana at Maejo (July to April) and Chomtong (September to April) exhibited seasonal fluctuation during the sampling period. At Maesa-mai, psyllid population fluctuated over time and existed year-round but less abundant from April to June. Both density-dependent and density-independent factors were apparently regulating the population density of H. cubana.
Despite the presence of leucaena shoot between May and August, the psyllid population could not be detected in Maejo and Chomthong and the surrounding areas.
Most of the indigenous predators associated with H. cubana were general predators but their role as regulating agents was not evident. No parasite was found in this investigation. Changes in the percentage of total nitrogen in the leucaena shoot during the sampling periods did not correlate with the population levels of H cubana. Fecundity and survival rate of H. cubana populations reared on leucaena seedling with and without shoot were not significantly different. No morphological changes in female and male genitalia of the psyllids were observed throughout the sampling periods.
Among the climatic factors, temperature correlated with population changes.