椰扁甲啮小蜂寄生对椰心叶甲蛹免疫反应的影响

为了测明椰扁甲啮小蜂Tetrastichus brontispae寄生对寄主椰心叶甲Brontispa longissima蛹的血细胞和体液免疫反应的影响，开展了椰扁甲啮小蜂寄生对椰心叶甲蛹血细胞数量和延展性、血淋巴酚氧化酶活性、血淋巴黑化百分率和血细胞凝集素活性等影响的研究。结果表明：与同期未被寄生蛹相比，寄生蛹血细胞总量在寄生后2 d显著降低，但寄生后4 d显著升高； 寄生蛹的浆血细胞延展率在寄生后2 d显著降低，寄生后4 d显著升高；寄生蛹的血淋巴黑化百分率在寄生后0.5～2 d较高，寄生后3～4 d降低直至为0；寄生蛹的血淋巴酚氧化酶活性在寄生后0.5 d，1 d和4 d时显著升高；寄生蛹的血凝素活性在寄生后2 d较高，寄生后1 d和4 d较低。结果说明椰扁甲啮小蜂寄生使寄主椰心叶甲蛹血细胞和体液免疫反应呈现不规律的变化。

Effects of parasitization by Tetrastichus brontispae (Hymenoptera:Eulophidae)on immunoreaction of the coconut hispine beetle,Brontispa longissima(Coleoptera:Chrysomelidae)

For evaluating the effects of parasitization by Tetrastichus brontispae on immunoreaction of Brontispa longissima, the changes of total number of hemocytes, the percentage of spread plasmatocytes, the rate of melanization, phenoloxidase activity and hemagglutin activity in the parasitized Brontispa longissima pupae were measured. The results indicated that compared with the unparasitized pupae, the parasitization by the parasitoid resulted in a significant decrease in the total number of hemocytes and the spread percentage of plasmatocytes at 2 d post parasitization and a significant increase in the parasitized pupae at 4 d post parasitization. The rate of melanization in the hemolymph in the parasitized pupae was higher than that of the unparasitized pupae during 0.5-2 d post parasitization and decreased to 0 in 3-4 d post parasitization. The phenoloxidase activity in the hemolymph in the parasitized pupae increased significantly at 0.5, 1 and 4 d post parasitization. A peak of the hemagglutin activity appeared at 2 d post parasitization in the parasitized pupae, which decreased to the lowest level at 1 and 4 d post parasitization. The results suggest that the parasitization by Tetrastichus brontispae may result in irregular changes of immunoreaction of its host Brontispa longissima.