The photosynthetic and structural differences between leaves and siliques of Brassica napus exposed to potassium deficiency.
The photosynthetic and structural differences between leaves and siliques of Brassica napus exposed to potassium deficiency.
复制标题
缺钾甘蓝型油菜叶片和长角果光合及结构差异
DOI：
10.1186/s12870-017-1201-5
复制
发表时间：
2017-12-11
影响因子：
5.3
通讯作者：
Lu J
中科院分区：
文献类型：
--
作者：
Lu Z;Pan Y;Hu W;Cong R;Ren T;Guo S;Lu J
缺钾条件下叶绿体光合作用的研究大多集中在叶片上；然而，钾对植物生殖结构的生理作用却知之甚少，而生殖结构在植物碳增益中起着至关重要的作用。以天然器官演替植物甘蓝型油菜（Brassica napus L.）为研究对象，比较了缺钾条件下叶片和叶片在形态、解剖和光生理上的差异。结果与叶片相比，气孔导度（gs）、表观量子产率（α）、羧化效率（CE）以及最大电子传递速率（Jmax）和核酮糖1,5-二磷酸（RuBP）羧化速率（Vcmax）的降低，限制了硅藻在缺钾（−K）或充足（+K）条件下CO2同化速率(A)显著降低。叶片Jmax、Vcmax和α的估计值与叶片叶绿素浓度（Jmax/Chl、Vcmax/Chl和α/Chl）的比值相近，均明显低于理论值，其中Jmax的估计值与理论值之间的差距最大。Jmax与Vcmax的平均比值比叶片低16.1%，表明电子传递减弱不足以满足碳同化的要求。气孔大而少，细胞间空间小而密集，叶绿体小而少，颗粒薄片薄，这可能与光捕获和CO2扩散减少有关。缺钾导致气孔大小、gs、叶绿体数量、α、Vcmax和Jmax均降低，叶片和叶片A显著降低，叶绿体与细胞壁间CO2扩散距离（dcl -cw）增加。与叶片相比，角质部对缺钾更为敏感，其组织K值和gs、Vcmax、Jmax、Dchl-cw等参数的降低幅度较小。结论
BackgroundMost studies of photosynthesis in chlorenchymas under potassium (K) deficiency focus exclusively on leaves; however, little information is available on the physiological role of K on reproductive structures, which play a critical role in plant carbon gain. Brassica napus L., a natural organ-succession species, was used to compare the morphological, anatomical and photo-physiological differences between leaves and siliques exposed to K-deficiency.ResultsCompared to leaves, siliques displayed considerably lower CO2 assimilation rates (A) under K-deficient (−K) or sufficient conditions (+K), limited by decreased stomatal conductance (gs), apparent quantum yield (α) and carboxylation efficiency (CE), as well as the ratio of the maximum rate of electron transport (Jmax) and the maximum rate of ribulose 1,5-bisphosphate (RuBP) carboxylation (Vcmax). The estimated Jmax, Vcmax and α of siliques were considerably lower than the theoretical value calculated on the basis of a similar ratio between these parameters and chlorophyll concentration (i.e. Jmax/Chl, Vcmax/Chl and α/Chl) to leaves, of which the gaps between estimated- and theoretical-Jmax was the largest. In addition, the average ratio of Jmax to Vcmax was 16.1% lower than that of leaves, indicating that the weakened electron transport was insufficient to meet the requirements for carbon assimilation. Siliques contained larger but fewer stoma, tightly packed cross-section with larger cells and fewer intercellular air spaces, fewer and smaller chloroplasts and thin grana lamellae, which might be linked to the reduction in light capture and CO2 diffusion. K-deficiency significantly decreased leaf and silique A under the combination of down-regulated stomatal size and gs, chloroplast number, α, Vcmax and Jmax, while the CO2 diffusion distance between chloroplast and cell wall (Dchl-cw) was enhanced. Siliques were more sensitive than leaves to K-starvation, exhibiting smaller reductions in tissue K and parameters such as gs, Vcmax, Jmax and Dchl-cw.Conclusion
登录
查看更多内容
甘蓝型油菜种子含油量的母体控制：长角果壁光合作用的作用
影响因子：
7.2
作者：
Hua, Wei;Li, Rong-Jun;Wang, Han-Zhong
通讯作者：
Wang, Han-Zhong
影响因子：
4.6
作者：
Kuai J;Sun Y;Zuo Q;Huang H;Liao Q;Wu C;Lu J;Wu J;Zhou G
通讯作者：
Zhou G
影响因子：
6.9
作者：
Furbank, RT;White, R;Turner, NC
通讯作者：
Turner, NC
影响因子：
6.4
作者：
Kalachanis, Dimitrios;Manetas, Yiannis
通讯作者：
Manetas, Yiannis
影响因子：
5.3
作者：
Kong L;Wang F;Feng B;Li S;Si J;Zhang B
通讯作者：
Zhang B