Kanu Sheku A, Barnabas Alban D, Przybylowicz Wojciech J, Mesjasz-Przybylowicz Jolanta, Dakora Felix D
Department of Crop Sciences, Tshwane University of Technology, Private Bag X680, Pretoria, 0001, South Africa.
Protoplasma. 2014 Jul;251(4):869-79. doi: 10.1007/s00709-013-0589-5. Epub 2013 Dec 24.
There is little information on in situ distribution of nutrient elements in N2-fixing nodules. The aim of this study was to quantify elemental distribution in tissue components of N2-fixing nodules harvested from Psoralea pinnata plants grown naturally in wetland and upland conditions in the Cape Fynbos. The data obtained from particle-induced X-ray emission revealed the occurrence of 20 elements (Si, P, S, Cl, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, As, Br, Rb, Sr, Y, Zr, Mo and Ba) in nodule components. Although, in upland plants, the concentrations of S, Fe, Si, Mn and Cu showed a steady increase from the middle cortex to the medulla region of P. pinnata nodules, in wetland plants, only S, Fe and Mn showed an increase in concentration from the middle cortex to the bacteria-infected medulla of P. pinnata nodules. By contrast, the concentrations of Cl, K, Ca, Zn and Sr decreased from middle cortex to nodule medulla. The alkaline earth, alkali and transition elements Rb, Sr, Y and Zr, never before reported in N2-fixing nodules, were found to occur in root nodules of P. pinnata plants grown in both wetland and upland conditions.
关于固氮根瘤中营养元素的原位分布情况，目前所知甚少。本研究的目的是量化从在开普植物区系湿地和旱地自然生长的补骨脂植物收获的固氮根瘤组织成分中的元素分布。从粒子诱导X射线发射获得的数据显示，在根瘤成分中存在20种元素（硅、磷、硫、氯、钾、钙、钛、锰、铁、镍、铜、锌、砷、溴、铷、锶、钇、锆、钼和钡）。虽然在旱地植物中，补骨脂根瘤从中间皮层到髓质区域，硫、铁、硅、锰和铜的浓度呈稳步上升趋势，但在湿地植物中，只有硫、铁和锰从补骨脂根瘤的中间皮层到被细菌感染的髓质浓度有所增加。相比之下，氯、钾、钙、锌和锶的浓度从中间皮层到根瘤髓质则有所下降。在湿地和旱地生长的补骨脂植物的根瘤中发现了碱土元素、碱金属元素以及过渡元素铷、锶钇和锆，这些元素在固氮根瘤中此前从未有过报道。
