Potential Risk of Hybridization in Ex Situ Collections of Two Endangered Species of Sinojackia Hu （Styracaceae）  

作　　者：Qi-Gang Ye Xiao-Hong Yao Sheng-Ju Zhang Ming Kang Hong-Wen Huang 

机构地区：[1]Wuhan Botanical Garden, the Chinese Academy of Sciences, Wuhan 430074, China [2]Graduate School of the Chinese Academy of Sciences, Beijing 100039, China

出　　处：《Journal of Integrative Plant Biology》2006年第7期867-872,共6页植物学报（英文版）

基　　金：Supported by the National Natural Science Foundation of China （30370153）, and the Key Project of the Knowledge Innovation of the Chinese Academy of Sciences （KSCX2-SW-104）.

摘　　要：Spontaneous hybridization in ex situ facilities can undermine the genetic integrity of ex situ collections and potentially contaminate open-pollinated seeds or seedlings destined for the reintroduction of endangered plant species into the wild. In the present study, the potential risk of hybridization between two endangered Chinese endemic species, namely Sinojackia xylocarpa Hu and S. rehderiana Hu, which are naturally allopatric species but were conserved ex situ in Wuhan Botanical Garden （WBG）, Wuhan, China, were investigated over three consecutive years from 2003 to 2005. The entire overlapping flowering period of the two species was 14-20 d and the two species shared the same pollinator insects during the entire flowering season in WBG. The floral isolation between the two species was not an issue in the ex sltu collection at WBG. The results suggest an opportunity for pollen transfer between species and a potential risk of genetic Introgression and loss of genetic identity of open-pollinated seeds produced in the ex sltu Collection of these two endangered species. An artificial reciprocal cross between S xylocarpa and S. rehderlana confirmed that the two congener species could readily set seeds, indicating no post-pollination barriers to hybridization and the importance of spatial isolation as a barrier to inter-specific crossing. Therefore, to manage these crossable species with overlapping flowering times and shared pollination vectors in ex situ facilities, spatial isolation should be carefully considered to minimize the possibility of spontaneous hybridization.Spontaneous hybridization in ex situ facilities can undermine the genetic integrity of ex situ collections and potentially contaminate open-pollinated seeds or seedlings destined for the reintroduction of endangered plant species into the wild. In the present study, the potential risk of hybridization between two endangered Chinese endemic species, namely Sinojackia xylocarpa Hu and S. rehderiana Hu, which are naturally allopatric species but were conserved ex situ in Wuhan Botanical Garden （WBG）, Wuhan, China, were investigated over three consecutive years from 2003 to 2005. The entire overlapping flowering period of the two species was 14-20 d and the two species shared the same pollinator insects during the entire flowering season in WBG. The floral isolation between the two species was not an issue in the ex sltu collection at WBG. The results suggest an opportunity for pollen transfer between species and a potential risk of genetic Introgression and loss of genetic identity of open-pollinated seeds produced in the ex sltu Collection of these two endangered species. An artificial reciprocal cross between S xylocarpa and S. rehderlana confirmed that the two congener species could readily set seeds, indicating no post-pollination barriers to hybridization and the importance of spatial isolation as a barrier to inter-specific crossing. Therefore, to manage these crossable species with overlapping flowering times and shared pollination vectors in ex situ facilities, spatial isolation should be carefully considered to minimize the possibility of spontaneous hybridization.

关 键 词：endangered species ex situ conservation hybridization risk PHENOLOGY POLLINATION Sinojackia rehderiana Sinojackia xylocarpa. 

分 类 号：Q944[生物学—植物学]