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 Aghanashini 河（14° 30′ 30″ N–74° 22′ 44″ E）上两个空间分离的红树林河口植物根系中丛枝菌根真菌 (AMF) 群落组成中的作用印度西海岸的 Gangavali（14° 35′ 26″ N–74° 17′ 51″ E）。两个红树林河口具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部扩增了 18S 小亚基 (SSU) rDNA 的 550-bp 部分，并通过限制性片段长度多态性 (RFLP) 对其进行了分析。对代表独特 RFLP 模式的克隆进行了测序。从分别在 Aghanashini 和 Gangavali 取样的 7 种和 5 种植物的根中获得了总共 736 个克隆。Aghanashini (12) 植物根中的 AMF 系统型数量高于 Gangavali (9)，表明两个红树林河口植物根中 AMF 群落组成的数量差异。由于两个河口具有相似的植物物种组成，河口之间 AMF 群落的数量差异可能是两个地点之间根际化学差异的一个属性。

非度量多维尺度 (NMDS) 揭示了两个站点的 AMF 社区的重叠。三个和两个 AMF 系统型分别在 Aghanashini 和 Gangavali 具有显着的指标值指数。适合 NMDS 排序的环境向量没有显示任何土壤变量对两个地点的 AMF 组成的显着影响。然而，在根际 P 上观察到植物宿主和位点的显着影响。我们的结果表明，根 AMF 群落组成可能是植物对根际变量的反应的结果。这表明植物特性可能在塑造红树林 AMF 群落中起主要作用。