Plant Science Department, Faculty of Science, Shahrekord University, Shahrekord, Iran.
Department of Ecology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran.
Environ Sci Pollut Res Int. 2024 Mar;31(14):21947-21961. doi: 10.1007/s11356-024-32515-7. Epub 2024 Feb 24.
Arsenic (As) is a hazardous metalloid, and mycorrhizal inoculation and vermicompost amendment can influence As bioremediation. However, the studies concerning the sole and joint effects of arbuscular mycorrhizal fungi (AMF) and vermicompost on the phytoremediation efficacy are limited. In the present study at first, the impact of various levels of vermicompost (0, 2, 4, and 8% w/w) was investigated on As mobility in soil and safflower (Carthamus tinctorius L.) plants grown in soils of spiked with 0, 40, and 80 mg kg As. Results revealed that with increasing dose of vermicompost, bioavailable As in soil decreased which resulted in a lower bioaccumulation factor and translocation factor (TF) and led to a significant increase of tolerance index (TI) and total chlorophyll content in plants. The highest effect on TI and total As accumulation per plant was obtained in the dosage of 8% vermicompost. Therefore, in the second experiment, the sole and joint effects of 8% vermicompost and inoculation with Rhizophagus intraradices were assessed on the tolerance and accumulation of As in safflower. The addition of vermicompost aggravated mycorrhizal colonization but did not significantly influence mycorrhizal dependency under As stress. The joint effects of AMF and vermicompost improved the dry weight of roots and shoots, increased P concentration and P:As ratio in shoots, reduced malondialdehyde content, and moderated ascorbate peroxidase activity in leaves of As-stressed plants. Interestingly, co-application of AMF and vermicompost more than their sole usage decreased As concentration in shoots and TF and more strongly increased total As accumulation per plant. These findings suggest that mycorrhizal inoculation and vermicompost have a synergistic effect on As tolerance and phytostabilization efficacy of safflower plants, and their combined application may be a new option to remediate As-contaminated soils.
砷（As）是一种有害的类金属，菌根接种和蚯蚓粪改良可以影响砷的生物修复。然而，关于丛枝菌根真菌（AMF）和蚯蚓粪单独和联合作用对植物修复效率的研究有限。在本研究中，首先研究了不同水平的蚯蚓粪（0、2、4 和 8%w/w）对添加 0、40 和 80mgkgAs 土壤中砷的移动性以及红花（Carthamus tinctorius L.）植物的影响。结果表明，随着蚯蚓粪剂量的增加，土壤中有效态砷减少，生物积累因子和转运因子（TF）降低，导致植物的耐受力指数（TI）和总叶绿素含量显著增加。在 8%蚯蚓粪剂量下，TI 和植物总砷积累量的最高效应。因此，在第二个实验中，评估了 8%蚯蚓粪和接种内根孢菌（Rhizophagus intraradices）对红花耐砷性和砷积累的单独和联合作用。蚯蚓粪的添加加重了菌根的定植，但在砷胁迫下，对菌根依赖性没有显著影响。AMF 和蚯蚓粪的联合作用提高了根和茎的干重，增加了茎中的磷浓度和磷砷比，降低了丙二醛含量，调节了砷胁迫下叶片中的抗坏血酸过氧化物酶活性。有趣的是，AMF 和蚯蚓粪的联合使用比单独使用更能降低地上部砷浓度和 TF，并更强烈地增加植物总砷积累量。这些发现表明，菌根接种和蚯蚓粪对红花植物的砷耐性和植物稳定化效果具有协同作用，它们的联合应用可能是修复砷污染土壤的一种新选择。
