Propagation technique of arbuscular mycorrhizal fungi isolated from coastal reclamation land

Abstract

Arbuscular mycorrhizal fungi (AMF) are well known for their plant growth promoting potential and stress tolerance ability. AMF promotes plant growth even at adverse environmental conditions and improve plant nutrient uptake. This study aimed to propagate AMF using a single spore inoculation technique. Soil samples were collected from salt affected Saemangeum reclaimed land. Collected soil samples were subjected to soil analysis. In the single spore inoculation method, sorghum sudangrass (Sorghum bicolor L.) was inoculated with a single spore. Among the 150 inoculants, six spores were able to germinate in vitro. Geminated spores were transferred to 1 kg pots containing sterilized field soil. After 120 days, the contents were mixed and transferred to 2.5 kg pots and maintained for another 120 days. After 240 days, spore count and colonization were checked. The propagated spores were identified using nested PCR followed by sequencing. The 18S rDNA sequencing of spores revealed that the spores belonged to Gigaspora margarita and Claroideoglomus lamellosum. Among the 6 inoculants, Claroideoglomus lamellosum S-11 (391 spore per 100 g of soil) had the highest spore count followed by Gigaspora margarita S-23 (235 spore per 100 g of soil). Slide method allowed visual monitoring of spore germination in vitro as well as being able to mass produce pure cultures of AMF for bio-inoculation purposes.