The population dynamic, life history and insecticide screening of Scirtothrips dorsalis Hood (Thysanoptera: Thripidae)

• Main Authors: Yan- Zi Li, 李燕姿
• Other Authors: Tsui-Ying Chang
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/57497447798474943532

碩士 === 國立屏東科技大學 === 植物醫學系所 === 98 === Scirtothrips dorsalis Hood (Inseta, Thysanoptera, Terebrantia, Thripidae) is highly polyphagous and widely distributive in tropical area. Because of its small size, it can hide in buds and leaves and be difficult to observe and control. It fed on Zizyphus mauritiana Lam. (Indian Jujube) and cause fruits damage. In order to understand the density, spatial distribution and population dynamic of S. dorsalis Hood, a field investigation was carried out in the Indian Jujube orchard in Talou Village, Ligang Township, Pingtung county. To analyze the amount of S. dorsalis Hood on different maturity leaves, the result show that S. dorsalis Hood prefers to feed on shoot leaves and with significant difference compared to old leaves. The β vaule of Iwao’s patchiness regression (IPR) and the b vaule of Taylor’s power law (TPL) indicated the aggregation dispersion of S. dorsalis Hood on Indian Jujube. Chosen a precision level of 0.05, estimates of sample size based on the assumption of IPR were 48,419, but TPL were only 407 when the density reaches 1 thrip per leaf. S. dorsalis Hood was raised at 20, 25 and 30℃on the leaf of Mangifera indica L. (Mango). The developmental time (from the egg to adult) was 22.3, 14.0 and 11.7 days, respectively. The developmental low threshold (℃) and accumulative effective temperature (DD) (from egg to adult emergence) was obtained as 11.0℃and 208.4DD. The best longevities of adult female and male thrip at 20℃ were 22.5 and 9.3 days, respectively. The intrinsic rate of increase (rm) was best 0.1342 day-1 at 30℃. The finite rate of increase (λ) was 2.055、2.095 and 2.144 day-1 at 20, 25 and 30℃, respectively. The net reproductive rate (R0) was highest 10.5 eggs/female at 30℃. The mean generation time (T) was shortest 17.8 day at 30℃. The insecticide screening includes Cabosulfan, Chlorfenapyr, Acetamiprid, Fipronil, Methomyl, Imidacloprid, Dinotefuran and Lambda-cyhalothrin for the S. dorsalis Hood. The mortality of nymphs after 12hrs were up to 100% with the treatment by Chlorfenapyr, Fipronil and Cabosulfan. 72 hrs after the treatment by Chlorfenapyr, Fipronil, Cabosulfan, Imidacloprid, Acetamiprid, Lambda-cyhalothrin and Methomyl were highly effective. The mortality of adult thrips after 12 hrs was up to 100% the treatment by Chlorfenapyr. 48 hrs after the treatment by Chlorfenapyr, Methomyl, Fipronil, Imidacloprid and Cabosulfan were highly effective and the statistical analysis shows no significant difference between them.