In this study, we collected 709 specimens of the sharpbelly Hemiculter leucisculus from the Yuanjiang River at monthly intervals between May 2017 and January 2019. An increment was formed annually in the lapillar otoliths, with the formation of annuli occurring between May and August, and peaking in June. Fish spawned from April to October, with a peak period between May and June. The radius of the first annulus varied apparently among individuals, reflecting differences in the duration of the growth period prior to annulus formation owing to extended spawning seasons. Three types of first annulus observed could reflect differences in the periods when the fish were born. The age of sampled fish ranged from 0 to 4 years, among which 1- and 2-year age classes predominated. The mean standard length (SL) at age and growth rate of this population did not differ significantly from those of other native populations. Analysis of life history traits indicated no obvious correlation with either latitude or habitat, whereas SL distribution and age composition were found to vary along a latitudinal gradient. Furthermore, mean SL at age and growth rate showed differences between native and invasive populations. Relatively stable life history traits of this species may explain its dominant status in diverse ecosystems, with plasticity in terms of body size and growth contributing to its successful invasion of different habitats.
雄性不育是水稻杂种优势利用的重要资源,对雄性不育现象的研究具有重要理论意义和实践价值。本研究以自然突变的水稻雄性不育突变体012S-3为试验材料,对其表型特征和花粉育性等进行调查,并构建遗传群体,利用分子标记对目的基因进行初步定位,然后应用基因组重测序技术对其进行精细定位。结果表明,012S-3是一个典型的无花粉普通型雄性不育材料,其不育性状受1对隐性核基因控制。初步定位分析目的基因与SSR标记RM6081存在连锁关系,其遗传距离约为34.4 c M;进一步的精细定位分析,找到3个候选基因:LOC_Os07g35880、LOC_Os07g35920和LOC_Os07g35940,其中LOC_Os07g35880和LOC_Os07g35940编码β-淀粉酶,属于水稻中新发现的花粉致死基因。该不育基因的成功定位为其进一步的分离克隆及其在水稻分子设计育种中的应用奠定了基础。 相似文献