Motherly care: How Leymus chinensis ramets support their offspring exposed to saline-alkali and clipping stresses
Motherly care: How Leymus chinensis ramets support their offspring exposed to saline-alkali and clipping stresses
复制标题
母性关怀：羊草分株如何支持暴露在盐碱和修剪压力下的后代
DOI：
10.1016/j.scitotenv.2021.149675
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发表时间：
2021
影响因子：
9.8
通讯作者：
Gao Yingzhi
中科院分区：
文献类型：
--
作者：
Sun Hao;Zheng Congcong;Chen Taiping;Postma Johannes A.;Gao Yingzhi
BackgroundWhile clonal integration can improve the performance of rhizomatous plants, it remains unclear whether their clonal integration strategy changes under contrasting clipping and saline-alkali homogeneous and heterogeneous environments.Leymus chinensisis a clonal grass native to the Songnen grassland where heavy grazing and patchy saline-alkali stress are serious environmental and ecological problems. We hypothesized thatL. chinensisovercomes these stresses through clonal integration, in particular the transfer of nitrogen and carbohydrates.MethodsA pot experiment was carried out with15N isotope soil labeling method to study clonal integration strategy in the connected mother and daughter ramets ofL. chinensis. The connected ramet pairs were grown in homogeneous (both connected ramets were treated) and heterogeneous (only daughter ramets were treated) environments with four treatments: control, clipping (60% aboveground biomass removal), saline-alkali (3.45 g of NaCl, NaHCO3, and Na2CO3per pot), and clipping × saline-alkali.ResultsA significant amount (22.5%) of15N was transferred from mother to daughter ramets under non-stressed conditions. When homogeneously stressing both mother and daughter ramets, N transfer was significantly reduced to 8.5‐–14.6%, independent of the nature of the stress. When only daughters were stressed (heterogeneous stress), saline-alkali stress led to a division of labor where daughters had enhanced photosynthesis, and mother ramets had increased15N uptake and growth. Clipping only daughters reduced biomass and15N uptake of both daughter and mother ramets.ConclusionsOur results demonstrated that clonal integration also occurs in homogeneous favorable environments but is reduced under homogeneous stress. In heterogeneous environments, clonal integration is used to translocate resource after clipping and a division of labor is established to overcome saline-alkali stress. Clonal integration continued even when daughters were severely stressed by the combined treatments. Our findings suggest that these mechanisms are key to the success ofL. chinensisin the Songnen grassland.
