"Phalaenopsis is the most important potted orchid genus in the world. However, the low seedling
survival rate, long vegetative growth period and disease outbreak are problems in production. Orchid
micorrhizal fungi (OMF) are their obligate partners in orchid physiology. Orchids use their symbionts to
gain access to organic and mineral nutrients by increasing nutrient absorption and translocation to
plants under natural conditions. The benefit of orchid mycorrhizal symbiosis using Phalaenopsis as
model plants was conducted. We inoculated in vitro grown plantlets of Doritaenopsis Taisuco Wonder
‘King Car Butterfly KC1111’ and Phalaenopsis Tai Lin Redangel ‘V31‘ with two OMF isolates,
Ceratobasidium sp. AG-A (R02) and Rizoctonia solani AG-6 (R04). The effects of OMFs on orchid plant
growth and Erwinia soft rot progression were examined after two months of ex vitro growth. The results
showed that the presence of OMFs in Phalaenopsis roots significantly increased the growth and soft rot
resistance of plants. Selectivity of cultivar type to different OMF was also observed. The relevance of
this findings and future work are discussed."
