Studies On The Population Dynamics And Pesticides Control Of Pseudophacopteron Canarium

The life history, the population dynamics and the natural enemies of Pseudophacopteron canarium Yang & Li were investigated in one-thousand-acre olive orchard in Yanshou village, Putian. This psylla had 8 generations per year, with generation overlapping and adults overwintering in Putian. There were six significant peaks in the occurrences of its eggs, nymphs (1-5 instar) and adults per year. The egg and nymph occurrences reached the highest peak at the autumn-shoot stage, whereas the eclosion reached its highest peak at the summer-shoot stage. The psylla population fluctuation had a close relation with the shoot occurrence of Canarium album. At each shoot stage, there were a peak of egg laying and a peak of nymph occurrence, and a significant high population growth rate was also observed. After the new shoot took shape, the population dramatically dropped to a low level with the occurrence and the peak of young nymphs 5-10 days later as compared with egg laying. Observed data indicated that natural enemies of Pseudophacopteron canarium Yang & Li were mostly the predators, which included large variety of species. Among the predators, ladybug, which took more than 70% of total natural enemies, was the predominant population, with Coelophora circumusta Mulsant and Phtynucaria congener (Schoenherr) being the dominant species.The toxicity of different kinds of pesticides to Pseudophacopteron canarium Yang & Li was examined in the laboratory. The results illustrated that the toxicity of 15 kinds of insecticides and 6 kinds of mixtures with different proportion to Pseudophacopteron canarium Yang & Li varied. Nymph tended to be most sensitive to 1% abamectin, 2.5% lambdacyhalothrin, and the mixture of 2.5% lambdacyhalothrin and 10% imidacloprin (12.5:1), with their relative toxicity indices more than 35 times as that of omethoate and LCso less than 1.7ug/mg.Pesticides which were determined to be relatively highly toxic were used for controlling Pseudophacopteron canarium Yang & Li in fields and 15 kinds ofpesticides were tested to be effective in controlling Pseudophacopteron canarium Yang & Li with the control effect lasting for more than 7 days and even still remaining above 90% 7 days after application. However, these pesticides performed significantly differently in terms of their quick-acting. 1% abamectin diluted with 2000 times, 2.5% lambdacyhalothrin with 2000 times, the mixture of 2.5% lambdacyhalothrin and 10% imidacloprin (12.5:1) with 2000 times and the mixture of 2.5% lambdacyhalothrin and 10% imidacloprin (1:2) with 2000 times were examined to be the best in both control effect and quick-acting with their control effects above 91.58% 1 day, effects above 99.03% 3 day, effects 100% 7 day after application, .Different measures of pesticide application were explored in this study. Conventional spraying was proved to be the best and stem-brushing and root-irrigating could cause plant harm by pesticides without good control effect to the insect pest.According to the indoor toxicity tests and field trials, 1% abamectin, 2.5% lambdacyhalothrin, and the mixture of 2.5% lambdacyhalothrin and 10% imidacloprin were the relatively ideal pesticides for controlling Pseudophacopteron canarium Yang & Li, could be developed, registered, produced and extended to be the new pesticides for controlling Pseudophacopteron canarium Yang & Li. With respect to the performance and cost, the mixture with the proportion of 1:2 (2.5% lambdacyhalothrin and 10% imidacloprin) would be the best.The control strategy for Pseudophacopteron canarium Yang & Li was also developed based on the above research results. The key prevention measure was to spray pesticides to prevent the shoot from being infected, especially the spring shoot. In the meantime, the role of natural enemies in controlling Pseudophacopteron canarium Yang & Li should be played to the full. With regard to the pesticide application, the pesticides with high efficiency, low residue and less harm to the natural enemies, such as pyrethrin and biological pestic...