The invasion of coastal areas in South China by Ipomoea cairica may be accelerated by the ecotype being more locally adapted to salt stress.

2018-11-23 本站

题目：The invasion of coastal areas in South China by Ipomoea cairica may be accelerated by the ecotype being more locally adapted to salt stress.

期刊：PLoS ONE

作者：Gang Liu1,2，Yang Gao2，Fang-Fang Huang2，Ming-Yue Yuan2，Shao-Lin Peng2

单位：1.College of Life Sciences, Shaanxi Normal University, 710119, Xi'an, China,  2.State Key Laboratory ofBiocontrol and Guangdong Key Laboratory of Plant Resources, Key Laboratory of Biodiversity Dynamics andConservation of Guangdong Higher Education Institutes, School of Life Sciences, Sun Yat-Sen University,510275, Guangzhou, China

摘要： Local adaptation and phenotypic plasticity are two alternative mechanisms used by invasiveplants for range expansion. We conducted a series of experiments to investigate the role ofthese mechanisms in the recent expansion of the invasive Ipomoea cairica from non-salineto salt-stressed coastal habitats. A comparison of the plant’s photosynthetic traits and con-struction costs across habitats was conducted through a field survey. Meanwhile, a full fac-torial greenhouse experiment was conducted with two ecotypes (non-saline and coastal) ofI. cairica and two salinity gradients (water and 4 g L-1NaCl solution) to evaluate the roles ofthe two strategies by comparing their main traits. The results revealed that the constructioncost and Amaxof I. cairica did not change with the habitat type. The ecotype and saline treat-ments, however, significantly influenced the plant growth. The non-saline ecotype (NE)generally sho wed higher or equal plasticity of biomass-allocation and functional traits com-pared to the coastal ecotype (CE). However, the fitness and biomass of the NE significantlydecreased with salinity, whereas those aspects of the CE did not change. Our results indi-cate that the recent expansion of I. cairica into coastal areas may be accelerated by thelocal adaptation of the CE to salt stress. Additionally, in South China, the CE will most likelyevolve adaptations to both sal ine and non-saline environments, which will further broadenthe invasion range of I. cairica in the future.