Desiccation tolerance in embryonic stages of the tardigrade
Desiccation tolerance in embryonic stages of the tardigrade
复制标题
缓步动物胚胎阶段的干燥耐受性
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
G. Fritz
中科院分区：
文献类型：
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作者：
R. O. Schill;G. Fritz
迟滞中常见的脱水耐受性使它们能够应对可用水的时间变化。虽然成虫的长期存活已在几个物种中得到证实，但卵和胚胎的脱水耐性研究较少，但从生态学和进化的角度来看，这是一个重要的方面。本研究首次评价了延迟性种延缓乳杆菌5个不同发育阶段在8个不同湿度水平(10、20、31、40、54、59、72、81%)下复水后的脱水耐性和随后的孵化成功率。湿度水平和发育阶段是决定孵化率的重要因素。结果表明，欠发达阶段对干燥非常敏感。发育前3天的低湿度水平会导致复水后孵化率下降。发育后期的胚胎孵化率高于早期干燥的胚胎。然而，在低湿度水平下快速干燥会导致复水后发育延迟和孵化率降低。一般来说，进一步发育的胚胎表现出比年轻阶段更好的生存能力。
Desiccation tolerance commonly found among tardigrades allows them to cope with temporal variation of available water. Although the long-term survival of adults has been demonstrated in several species, desiccation tolerance of eggs and embryos is less well studied, however it is an important aspect from an ecological and evolutionary point of view. For the first time we evaluated the desiccation tolerance and subsequent hatching success of five different developmental stages of the tardigrade species Milnesium tardigradum, when rehydrated following drying at eight different humidity levels (10, 20, 31, 40, 54, 59, 72, 81%). Humidity level and developmental stage are significant factors in determining successful hatch rates. The results showed that the less developed stages were quite sensitive to desiccation. Low humidity levels during the first 3 days of development lead to a decrease in hatch rates following rehydration. Later developmental stages showed higher hatch rates than embryos dried at earlier stages. However, fast drying at low humidity levels resulted in delayed development and lower hatch rates following rehydration. In general, further developed embryos exhibit a better survival capacity compared with younger stages.