生石灰对福寿螺的毒性效应研究

通过室内毒性试验,探索了生石灰对不同大小福寿螺的毒性效应。试验中将福寿螺按照壳高（H）分为小螺（5 mm≤H〈15 mm）、中螺（15 mm≤H〈25 mm）、大螺（25 mm≤H〈35 mm）和超大螺（35 mm≤H〈45 mm）,结果表明：（1）生石灰的控螺效应显著,尤其是对中小福寿螺具很强的抑制和杀灭作用;生石灰处理6 d,除了最低质量浓度0.05 g.L-1处理造成35%死亡率,其他处理死亡率均在70%以上,其中0.20、0.50、1.00和2.00 g.L-1处理中超过90%的福寿螺死亡。（2）生石灰对不同大小福寿螺的半抑制质量浓度（24 h）大小顺序为超大螺〉中螺、大螺〉小螺,半致死质量浓度（24 h）大小顺序为超大螺〉大螺〉中螺〉小螺;（3）生石灰对福寿螺的毒性以抑制效应为主,生石灰对福寿螺的平均半抑制质量浓度为0.06～0.22 g.L-1,低于平均半致死质量浓度0.11～1.09 g.L-1;（4）0.50 g.L-1和2.00 g.L-1质量浓度的石灰处理12 h后,福寿螺鰓组织SOD酶活性呈极显著下降,分别为对照的33%和38%。研究表明,生石灰可用于防治入侵生物福寿螺,在实践中可部分替代杀螺剂的使用。

Study on the toxic effect of calcium oxide on Pomacea canaliculata

In this study,molluscicidal activity of calcium oxide against Pomacea canaliculata was evaluated under laboratory conditions.According to the shell height（H）,snails were divided into four groups including small size（5 mm≤H15 mm）,medium size（15 mm≤H25 mm）,large size（25 mm≤H35 mm） and extra large size（35 mm≤H45 mm）.Experimental results showed that（1）The molluscicidal characteristic of calcium oxide was significant on Pomacea canaliculata,especially on the small and medium size of snail.After 6 days,except 0.05 g·L-1 treatment with 35% mortality,all other treatments resulted in above 70% mortality of Pomacea canaliculata.Furthermore,treatments of 0.20,0.50,1.00 g·L-1 and 2.00 g·L-1 killed Pomacea canaliculata completely;（2） The order of median inhibitive concentration（24 h） of calcium oxide on different sizes of snails was extra large size medium size and large size small size.Also,the order of median lethal concentration（24 h） on different sizes of snails of calcium oxide was extra large size large size medium size small size;（3） The inhibitive effect of calcium oxide on Pomacea canaliculata was stronger than the lethal effect greatly;the mean inhibitive effect of calcium oxide ranged from 0.06 g·L-1 to 0.22 g·L-1,and the mean lethal effect of calcium oxide ranged from 0.11 g·L-1 to 1.09 g·L-1.（4） After 12 h,SOD activities in the gills of Pomacea canaliculata were significantly decreased by 33% and 38% in the treatments of 0.50 g·L-1 and 2.0 g·L-1 respectively,compared with the control.In the experiment,calcium oxide showed toxic effect on Pomacea canaliculata to a certain extent,and it would be helpful in partly substituting the conventional chemical molluscicides in farming practice.