The nutritional significance of sterol metabolic constraints in the generalist grasshopper Schistocerca americana
The nutritional significance of sterol metabolic constraints in the generalist grasshopper Schistocerca americana
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DOI：
10.1016/s0022-1910(98)00131-0
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发表时间：
1999-04-01
影响因子：
2.2
通讯作者：
Elias, DO
中科院分区：
文献类型：
--
作者：
Behmer, ST;Elias, DO
甾醇是蚱蜢以及所有其他昆虫的必需营养素，但代谢限制可能会限制支持正常生长和发育的植物甾醇。在当前的研究中，利用美洲蝗虫解决了与蝗虫甾醇营养相关的两个问题：（1）甾醇数量如何影响生长和存活，以及（2）不同浓度的合适和不合适的甾醇混合物如何影响生长和存活？第一个实验的结果表明，该蝗虫物种的最低甾醇需求量为 0.05% 干重；然而，当甾醇数量增加到该浓度以上时，存活率和性能并没有提高。第二个实验的结果揭示了蚱蜢甾醇营养的两个新方面：（1）当合适的甾醇受到限制时，大多数个体不能使用不合适的甾醇来满足最低甾醇需求（即不发生节约），以及（2）超过一定阈值，即使合适的甾醇以单独允许正常生长和发育的浓度存在，不合适的甾醇也是有害的。我们在 蚱蜢的甾醇代谢限制如何影响觅食。 (C) 1999 Elsevier Science Ltd. 保留所有权利。
Sterols are essential nutrients for grasshoppers, as well as all other insects, but metabolic constraints can limit which phytosterols support normal growth and development. In the current study, the generalist grasshopper Schistocerca americana was used to address two questions related to grasshopper sterol nutrition: (1) how does sterol quantity influence growth and survival, and (2) how do mixtures of suitable and unsuitable sterols at different concentrations influence growth and survival? Results from the first experiment indicated that this grasshopper species had a minimum sterol requirement of 0.05% dry weight; as sterol quantity increased above this concentration, however, survival and performance were not enhanced. Results from the second experiment revealed two novel aspects of sterol nutrition in grasshoppers: (1) when suitable sterols were limiting, most individuals could not use unsuitable sterols to meet the minimum sterol requirement (i.e. no sparing occurred), and (2) above a certain threshold, unsuitable sterols were deleterious even when suitable sterols were present at a concentration that alone permits normal growth and development We discuss these physiological findings in terms of how sterol metabolic constraints in grasshoppers might influence foraging. (C) 1999 Elsevier Science Ltd. All rights reserved.