浙江丽水中华大蟾蜍和黑眶蟾蜍蝌蚪对水位变化的表型响应

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 浙江丽水中华大蟾蜍和黑眶蟾蜍蝌蚪对水位变化的表型响应 DOI: 10.5846/stxb201404280845 作者: 作者单位: 丽水学院生态学院,丽水学院生态学院,丽水学院生态学院,丽水学院生态学院,丽水学院生态学院,丽水学院生态学院,丽水学院生态学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目(31270443, 30970435); 浙江省大学生科技创新活动计划(2012R429022) Phenotypic responses to water level change in Bufo gargarizans and Duttaphrynus melanosticus tadpoles at Lishui, Zhejiang Author: Affiliation: College of Ecology,Lishui University,College of Ecology,Lishui University,College of Ecology,Lishui University,College of Ecology,Lishui University,College of Ecology,Lishui University,College of Ecology,Lishui University,College of Ecology,Lishui University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:全球气候变暖引发栖息地干涸将对生活在水中的无尾类幼体提出了挑战。通过浙江丽水中华大蟾蜍(Bufo gargarizans)和黑眶蟾蜍(Duttaphrynus melanosticus)蝌蚪在实验条件下对不同水位变化的表型响应,检测表型可塑性的遗传性和环境近因性影响。结果表明,水位变化对中华大蟾蜍蝌蚪早期发育历期、头宽和体重影响不显著,对体长影响显著,其中逐减水位最大、恒低水位最小,慢波、恒高与快波、逐增水位依次减少;水位变化对黑眶蟾蜍蝌蚪早期发育历期、体长、头宽和体重影响均显著;发育历期以恒高水位最大,恒低水位最小;体长以逐减水位最大,恒低、快波和慢波水位显著偏小,逐增和快波水位居中;头宽以恒低水位最小,逐增水位居中,其余较大;体重以恒低水位最小、恒高水位最大,其余居中。水位变化对中华大蟾蜍蝌蚪的变态时间、体长、头宽和体重影响均不显著;水位变化对黑眶蟾蜍蝌蚪的变态时间、体长和体重影响均显著,对头宽影响不显著;恒低水位的变态时间最长,恒高水位的变态时间最短,其他水位变化之间差异不显著;恒高水位的体长最大,恒低和快波水位最小,其他居中;逐增和快波水位的体重最大,恒低水位最小。研究结果表明,繁殖季节不同的中华大蟾蜍和黑眶蟾蜍蝌蚪响应水位变化的表型可塑性差异显著,长期在容易发生干旱和水位变化的冬季繁殖的中华大蟾蜍蝌蚪的表型可塑性低,在雨水充沛的春季繁殖的黑眶蟾蜍蝌蚪的表型可塑性高,表现出表型可塑性的种间差异和遗传性;在早期发育过程中,两种蝌蚪体长的共同的表型变异与缺乏遗传基础的环境近因性影响有关;黑眶蟾蜍蝌蚪对低水位或水位下降作出减速分化的消极响应,响应程度与环境信号的强弱直接相关。 Abstract:Habitat drying caused by global warming will raise a challenge for anuran larvae living in water. We investigated the phenotypic response to six different patterns of water level change in Bufo gargarizans and Duttaphrynus melanosticus tadpoles under laboratory conditions. The aim of this study was to examine the heritable basis and environmental proximate causes of phenotypic plasticity of these two species tadpoles. The results showed that all the six water level treatments had no significant effect on the early development Gosner stage (GS), head width (HW), or body mass (BM) of B. gargarizans tadpoles on the 14th day, but there was a significant effect on their snout-vent length (SVL). The SVL of B. gargarizans tadpoles raised in decreasing water levels were the longest, while the ones raised in constant low water levels had the shortest SVL than the remaining groups. Conversely, the six water level treatments had respectively significant effects on the GS, SVL, HW and BM of D. melanosticus tadpoles on the same day, respectively. Firstly, those tadpoles raised in constant high water level developed most fast, while the ones raised in constant low water level developed most slowly. Secondly, the tadpoles raised in decreasing water level had greater SVL, while the ones raised in constant low, fast fluctuation and slow fluctuation water levels had smaller SVL than the remaining groups. Thirdly, HW of the tadpoles raised in constant low water levels was the narrowest, followed by the ones raised in increasing water levels, the others raised in the remaining water level groups had the biggest HW. Lastly, BM of tadpoles in constant low water levels was the smallest, while the ones raised in constant high water level had heavier BM than the remaining groups. The water level treatments had no significant effect on the time of metamorphosis and body size at metamorphosis including SVL, HW, and BM in B. gargarizan. However, there were significant effects of the water level changes on the time of metamorphosis and body size at metamorphosis including SVL and BM, except for HW, in D. melanosticus. Tadpoles raised in the constant low water levels had protracted metamorphosis, whereas the tadpoles raised under the constant high water levels had shortened metamorphosis. SVL at metamorphosis of D. melanosticus in the constant high water levels was the largest, while the ones raised in constant low and rapidly fluctuating water levels were the shortest. BM at metamorphosis of D. melanosticus raised in the increasing and rapidly fluctuating water levels were the biggest, while the ones raised in the constant low water levels were the smallest. Our results suggest that there are significant interspecific differences in the phenotypic plasticity respond to desiccation risks between B. gargarizans and D. melanosticus tadpoles: the former was weaker than the latter. Winter-breeder B. gargarizans tadpoles experienced habitat drying more frequently, while spring-breeder D. melanosticus tadpoles experienced habitat drying rarely. This showed the interspecific differences and hereditary of the phenotypic plasticity. During the early development of the two toad tadpoles, the common phenotypic variations in their SVL were associated with lack of genetic basis of environmental proximate causes. The response to constant low or decreasing water level in D. melanosticus tadpoles was negative (deceleration of differentiation), and the response degree was directly related to the strength of the environmental signals. 参考文献 相似文献 引证文献