大蒜对四角蛤蜊早期生长发育的影响

摘要

[Objective] The research aimed to study the disease prevention effect and application method of garlic in the early growth and development of Mactra veneriformis.[Method] Using index gradient method,the effects of various concentrations of garlic extracts (0,2,4,8,16,32 mg/L) on early growth and development of M.veneriformis and the growth and survival of juvenile shellfish after returning to normal seawater were studied.[Result] The hatching rate of D-larvae increased to the highest (8 mg/L,P ＜ 0.05) and then decreased as the concentration of garlic extracts increased.During the planktonic stage,the larvae survival rate showed a "S" trend with the increasing of garlic extracts concentrations and the optimal concentration of garlic extracts was 2 mg/L(P ＜ 0.05).As garlic extracts concentrations increased,the metamorphic rate of larvae decreased,the metamorphism time was postponed and the size were decreased.The growth and survival of larvae and juveniles were depressed by continuously feeding garlic extracts for a long term.After juveniles returned to normal seawater 72 h,the survival rate of juveniles in different groups had no significant difference (P ＞ 0.05).And the survival rate of juveniles in different groups were all more than 85％ after juveniles returned to normal seawater 15 and 25 days (P ＞ 0.05).But 2 mg/L and 4 mg/L garlic extracts groups showed extremely significant predominance in relative growth (P ＜ 0.05).[Conclusion] The research provided scientific basis for early disease resistance of M.veneriformis.%[目的]研究大蒜在四角蛤蜊早期生长发育过程中的防病效果及应用方法.[方法]采用指数梯度设置法,研究了不同大蒜汁浓度(0、2、4、8、16、32 mg/L)对四角蛤蜊早期生长发育及停用大蒜汁后稚贝的生长与存活的影响.[结果]D型幼虫的孵化率随大蒜汁浓度的增加先升高后降低,最高点出现在8 mg/L处(P＜0.05)；浮游期间,幼虫的存活率随大蒜汁浓度的增加呈“S”型变化,以2mg/L为最适浓度(P＜0.05).随着大蒜汁浓度的增加,幼虫的变态率降低、变态延迟、变态规格小型化.长期连续投喂大蒜汁抑制了幼虫及稚贝的生长与存活.停用大蒜汁后72 h,各处理组稚贝的存活率无显著差异(P＞0.05).停用后第15天和第25天,各处理组存活率均大于85％ (P ＞0.05),但2 mg/L组和4 mg/L组均表现出极显著的相对生长优势(P＜0.05).[结论]该研究为四角蛤蜊早期抗病提供了科学依据.