不同补水方式对白星花金龟水分平衡的影响

为研究水分散失和水分补充对新疆新害虫白星花金龟Potosia brevitarsis Lewis的影响,在30℃恒温条件下,采用重量法测定白星花金龟脱水过程以及不同补水方式下(补蒸馏水;补盐水;补糖水)体内水分含量的变化,并与步甲、拟步甲的水分代谢进行比较。结果表明,白星花金龟的脱水与拟步甲科的网目拟地甲Opatrum subaratum Fald相似,在10h内脱水率均约为5%,而斑步甲Anisodactylus signatus 10h内脱水率约为20%。不同补水处理后,白星花金龟体内含水量迅速增加,随后继续脱水;脱水10d后,补蒸馏水、补盐水和补糖水处理的白星花金龟脱水率分别为28%,27%和21%,而未补水白星花金龟的脱水率为34%;未补水处理的甲虫脱水率和补蒸馏水和补盐水处理之间无显著性差异,而和补糖水处理之间存在显著性差异。未补水、补蒸馏水、补盐水和补糖水处理的LT50分别约为9,12,13和17d,补糖水能有效延长甲虫的存活时间。糖能有效地增加白星花金龟体内含水量,对维持其体内水分平衡起重要作用。

The effects to water balance of the leaf chafer Potosia brevitarsis under different water supplying

In order to determine the effect of dehydration and hydration to the leaf chafer Potosia brevitarsis Lewis, the beetles were measured the change of body water by weighting body mass during dehydration and hydrations including supplying distilled water, salt and sugar under constant 30℃. At the same time, the water loss of leaf chafer was compared with carabid and tenebrionid. The results indicate that the rates of water loss of leaf chafer P. brevitarsis were close to tenebrionid, whose rates of water loss were low. The rates of water loss of leaf chafer and tenebrionid were about 5% , and that of carabid were about 20%, within 10 h. After supplying water, the water of body was increased rapidly. The rates of water loss for dehydration were about 34 %, and for supplying distilled water, salt, sugar were 28%, 27%, 21% , respectively. And supplying distilled water and salt have no difference with dehydration, while supplying sugar significantly differed with dehydration. The LT50 of dehydrate and supplying distilled water, salt, sugar were 9, 12, 13 and 17 d. Supplying sugar could prolong the life of leaf chafer effectively. So sugar could increase the body water of P. brevitarsis effectively, and play an important role in water balance.