Laboratory of Soil Biology and Microbial Ecology, Department of Environmental Studies, University of Delhi, Delhi, 110 007, India.
Department of Botany, Zakir Husain Delhi College, University of Delhi, Delhi, 110 002, India.
Mycorrhiza. 2021 Nov;31(6):699-711. doi: 10.1007/s00572-021-01049-y. Epub 2021 Sep 3.
We investigated the role of plant host and soil variables in determining arbuscular mycorrhizal fungi (AMF) community composition in plant roots of two spatially separated mangrove estuaries on the rivers Aghanashini (14° 30' 30″ N-74° 22' 44″ E) and Gangavali (14° 35' 26″ N-74° 17' 51″ E) on the west coast of India. Both mangrove estuaries had similar plant species composition but differed in soil chemistries.We amplified a 550-bp portion of 18S small subunit (SSU) rDNA from mangrove plant roots and analysed it by restriction fragment length polymorphism (RFLP). Clones representing unique RFLP patterns were sequenced. A total of 736 clones were obtained from roots of seven and five plant species sampled at Aghanashini and Gangavali, respectively. AMF phylotype numbers in plant roots at Aghanashini (12) were higher than at Gangavali (9) indicating quantitative differences in the AMF community composition in plant roots at the two mangrove estuaries. Because both estuaries had similar plant species composition, the quantitative difference in AMF communities between the estuaries could be an attribute of the differences in rhizospheric chemistry between the two sites.Non-metric multidimensional scaling (NMDS) revealed overlap in the AMF communities of the two sites. Three and two AMF phylotypes had significant indicator value indices with specific hosts at Aghanashini and Gangavali, respectively. Environmental vector fitting to NMDS ordination did not reveal a significant effect of any soil variable on AMF composition at the two sites. However, significant effects of both plant hosts and sites were observed on rhizospheric P. Our results indicate that root AMF community composition may be an outcome of plant response to rhizospheric variables. This suggests that plant identity may have a primary role in shaping AMF communities in mangroves.
我们研究了植物宿主和土壤变量在确定印度西海岸阿加纳希尼河（14°30'30″N-74°22'44″E）和甘加瓦利河（14°35'26″N-74°17'51″E）两个空间分离的红树林河口植物根系中丛枝菌根真菌（AMF）群落组成中的作用。两个红树林河口都有相似的植物物种组成，但土壤化学性质不同。我们从红树林植物根系中扩增了 18S 小亚基（SSU）rDNA 的 550bp 片段，并通过限制性片段长度多态性（RFLP）进行了分析。代表独特 RFLP 模式的克隆被测序。从阿加纳希尼和甘加瓦利分别采集的 7 种和 5 种植物根系中获得了总共 736 个克隆。阿加纳希尼（12）植物根系中的 AMF 系统发育数量高于甘加瓦利（9），表明两个红树林河口植物根系中 AMF 群落组成存在定量差异。由于两个河口都有相似的植物物种组成，因此两个河口之间 AMF 群落的定量差异可能是两个地点根际化学差异的属性。非度量多维标度（NMDS）显示两个地点的 AMF 群落存在重叠。在阿加纳希尼和甘加瓦利，分别有 3 个和 2 个 AMF 系统发育具有与特定宿主相关的显著指示值指数。NMDS 排序的环境向量拟合未显示任何土壤变量对两个地点 AMF 组成的显著影响。然而，植物宿主和地点对根际 P 都有显著影响。我们的结果表明，根际 AMF 群落组成可能是植物对根际变量反应的结果。这表明植物身份可能在塑造红树林中的 AMF 群落方面发挥主要作用。
