Niazi Nabeel Khan, Bibi Irshad, Fatimah Ayesha, Shahid Muhammad, Javed Muhammad Tariq, Wang Hailong, Ok Yong Sik, Bashir Safdar, Murtaza Behzad, Saqib Zulfiqar Ahmad, Shakoor Muhammad Bilal
a Institute of Soil and Environmental Sciences, University of Agriculture Faisalabad , Faisalabad , Pakistan.
b MARUM and Department of Geosciences , University of Bremen , Bremen , Germany.
Int J Phytoremediation. 2017 Jul 3;19(7):670-678. doi: 10.1080/15226514.2016.1278427.
In this study, we examined the potential role of phosphate (P; 0, 50, 100 mg kg) on growth, gas exchange attributes, and photosynthetic pigments of Brassica napus and Brassica juncea under arsenic (As) stress (0, 25, 50, 75 mg kg) in a pot experiment. Results revealed that phosphate supplementation (P100) to As-stressed plants significantly increased shoot As concentration, dry biomass yield, and As uptake, in addition to the improved morphological and gas exchange attributes and photosynthetic pigments over P0. However, phosphate-assisted increase in As uptake was substantially (up to two times) greater for B. napus, notably due to higher shoot As concentration and dry biomass yield, compared to B. juncea at the P100 level. While phosphate addition in soil (P100) led to enhanced shoot As concentration in B. juncea, it reduced shoot dry biomass, primarily after 50 and 75 mg kg As treatments. The translocation factor and bioconcentration factor values of B. napus were higher than B. juncea for all As levels in the presence of phosphate. This study demonstrates that phosphate supplementation has a potential to improve As phytoextraction efficiency, predominantly for B. napus, by minimizing As-induced damage to plant growth, as well as by improving the physiological and photosynthetic attributes.
在本研究中，我们通过盆栽试验，研究了磷（P；0、50、100毫克/千克）在砷（As）胁迫（0、25、50、75毫克/千克）下对甘蓝型油菜和芥菜型油菜生长、气体交换特性及光合色素的潜在作用。结果表明，向受砷胁迫的植株补充磷（P100），除了与P0相比改善了形态、气体交换特性及光合色素外，还显著提高了地上部砷浓度、干生物量产量及砷吸收量。然而，在P100水平下，与芥菜型油菜相比，甘蓝型油菜通过磷辅助增加的砷吸收量显著更高（高达两倍），这主要是由于地上部砷浓度和干生物量产量更高。虽然在土壤中添加磷（P100）导致芥菜型油菜地上部砷浓度增加，但主要在50和75毫克/千克砷处理后，地上部干生物量减少。在有磷存在的情况下，所有砷水平下甘蓝型油菜的转运系数和生物富集系数值均高于芥菜型油菜。本研究表明，补充磷有潜力通过最小化砷对植物生长的损害以及改善生理和光合特性，来提高砷的植物提取效率，这在甘蓝型油菜中尤为明显。
