传统稻鱼系统中“田鲤鱼”的形态特征

稻田养鱼是一种重要的传统农业系统,养殖在稻田中的鲤鱼,在长期的自然选择和人工选择下逐渐形成了适应于稻田浅水环境的“田鲤鱼”.本研究以具有千年历史的全球重要农业文化遗产系统“青田稻鱼共生系统”和“从江稻鱼鸭系统”的青田田鱼和从江田鱼为范例,通过采样对两种“田鲤鱼”进行传统形态学分析和地标几何形态学分析;采用线粒体基因构建系统发育树;通过数据库数据提取和采样测量对两种“田鲤鱼”和其他常见鲤鱼种群或品系进行传统形态学聚类分析.传统形态学分析和地标几何形态学分析表明,青田田鱼和从江田鱼在形态上存在差异,与青田田鱼相比,从江田鱼尾部长而窄,体型较细长,尾部长度占身体长度比例小.对这两种田鱼及养殖于其他水体的其他鲤鱼种群进行系统发育树分析表明,青田田鱼和从江田鱼在遗传上是独立的种群;但形态聚类分析表明,这两种田鱼归为一类,明显不同于其他鲤鱼种群或品系,与其他鲤鱼种群的差异主要表现在背鳍和尾鳍上.这些研究结果说明,长期生活在稻田环境的青田田鱼和从江田鱼在遗传和形态上均明显不同于其他水体养殖鲤鱼种群,且青田田鱼和从江田鱼之间形态上存在差异.

Morphological traits of indigenous field carps maintained in traditional rice-based farming systems.

Rice-fish is an important traditional farming system. In the rice-fish system, common carp (Cyprinus carpio) is the major species raised in paddy field where the environment is characterized by shadow water. Under a long-term of natural selection and artificial selection, the carp would adapt to the paddy field environment. We investigated two indigenous carps (C. carpio qingtianensis and C. carpio congjiangensis) that originated and evolved in the Globally Important Agriculture Heritage System (GIAHS) ‘rice-fish system’ in Qingtian, Zhejiang Province and ‘rice-fish-duck system’ in Congjiang, Guizhou Province. We measured the morphological traits of indigenous carps by collecting carp samples from ‘rice-fish system’ and ‘rice-fish-duck system’. We used mitochondrial gene (D-loop) to build phylogenetic tree. We also collected data of morphological traits of other carp populations from documented databases and published papers. Both traditio-nal morphometric analysis and landmark based geometric morphometric analysis showed that Qingtian field carp and Congjiang field carp differed in body shape. Compared with Qingtian field carp, Cong-jiang field carp had a longer and more narrow tail, and lower ratio of tail length to body length. The analysis of phylogenetic tree suggested that Qingtian field carp and Congjiang field carp were genetically independent populations. However, principal component analysis basing on morphometric traits showed that the field carps (Qingtian field carp and Congjiang field carp) were morphometrically similar to each other and were both significantly different from other common carp populations, especially in the traits of caudal fin and dorsal fin. All these results suggested that carps living and evolving in paddy field environment were significantly different in genetics and morphology from the carp populations living in other water environment and that Qingtian field carp was morphologically different from Congjiang field carp.