Cell wall properties in Oryza sativa influence mesophyll CO2 conductance
Cell wall properties in Oryza sativa influence mesophyll CO2 conductance
复制标题
红豆杉的细胞壁特性影响叶绿体中层的二氧化碳传导性
DOI：
10.1111/nph.15173
复制
发表时间：
2018-07-01
期刊：
影响因子：
9.4
通讯作者：
Cousins, Asaph B.
中科院分区：
文献类型：
--
作者：
Ellsworth, Patricia, V;Ellsworth, Patrick Z.;Cousins, Asaph B.
CO2从叶片细胞间空气空间向羧化位点的扩散（g(m)）是提高CO2同化净速率（a (net)）、光合效率和作物生产力的潜在特性。叶片解剖在这一过程中起着关键作用；然而，很少有关于细胞壁特性如何影响g(m)和A（net）的研究。利用在线碳同位素判别法测定了高、弱光生长条件下野生型（WT）和细胞壁混合连锁生产（MLG）中断（Cs/F6敲除）突变体的g(m)和A（net）。还分析了细胞壁厚度（T-cw）、叶绿体暴露于细胞间隙的表面积（S-c）、每面积叶片干质量（LMA）、有效孔隙度和其他叶片解剖性状。Cs/F6突变体的g(m)相对WT降低了83%，其中28%的g(m)减少是由S-c引起的。虽然A(net)/LMA和A(net)/Chl部分解释了基因型间A（net）的差异，但细胞壁特性的变化影响了CO2的扩散率和可利用性。本文的数据表明，Cs/F6植物的MLG损失对g(m)有影响，并证明了细胞壁有效孔隙度和液路长度对g(m)的重要性。
Diffusion of CO2 from the leaf intercellular air space to the site of carboxylation (g(m)) is a potential trait for increasing net rates of CO2 assimilation (A(net)), photosynthetic efficiency, and crop productivity. Leaf anatomy plays a key role in this process; however, there are few investigations into how cell wall properties impact g(m) and A(net).Online carbon isotope discrimination was used to determine g(m) and A(net) in Oryza sativa wild-type (WT) plants and mutants with disruptions in cell wall mixed-linkage glucan (MLG) production (Cs/F6 knockouts) under high- and low-light growth conditions. Cell wall thickness (T-cw), surface area of chloroplast exposed to intercellular air spaces (S-c), leaf dry mass per area (LMA), effective porosity, and other leaf anatomical traits were also analyzed.The g(m) of Cs/F6 mutants decreased by 83% relative to the WT, with c.28% of the reduction in g(m) explained by S-c. Although A(net)/LMA and A(net)/Chl partially explained differences in A(net) between genotypes, the change in cell wall properties influenced the diffusivity and availability of CO2.The data presented here indicate that the loss of MLG in Cs/F6 plants had an impact on g(m) and demonstrate the importance of cell wall effective porosity and liquid path length on g(m).