A preliminary study on the status of vesicular Arbuscular mycorrhizal associations with mangrove plants in Sri Lanka

Abstract

The symbiosis between Arbuscular Mycorrhizal Fungi (AMF) and mangrove plant species was investigated in five mangrove swamps in Sri Lanka. Soil samples were collected from rhizosphere areas of dominant mangrove plants in Sarasalai area in Jaffna, Kakkapalliya in Pambala, Negambo lagoon, Trincomalee, and Manmunai Batticaloa, from a depth of 0-20 cm on from March to September 2018, during low tide period. Collected soil samples were clay loam in texture. For all five composite samples AMF spores were extracted using wet sieving and decanting method. Most common mangrove plants species were identified and their underground growing root tips were extracted to assess the colonization percentage of AMF. The results were compared using a one-way ANOVA in Minitab 16.0. AMF were mostly found in the form of hyphae and were commonly associated with most of the mangrove species investigated. AMF species belonging to Glomus, Gigaspora, Scutellospora and Acaulospora were identified in all areas. Root colonization was observed in all species. AM fungal root colonization varied by plant species and site. Lumnitzera racemosa was common to Jaffna and Pambala and the colonization potential was high in Jaffna compared to that of Pambala, but was not significant (at p < 0.554). Rhizophora apiculata in Pambala and Negambo was not significantly different (p<5) so as Avicennia marina in Pambala Batticaloa and Tricomalee. Furthermore, colonizing AMF species can be identified and recommended for inoculating mangrove seedlings in deforested areas for better growth and development of sustainable mangrove ecosystem.