Arbuscular mycorrhizae of five summer geophytes from Cluj county

Abstract

Phytobiont enhanced nutrient uptake through arbuscular mycorrhiza comes at a cost in form of carbon fixed through photosynthesis. Geophytes operate under resource efficiency constraint due to their particular life-cycle and have to balance it very well. This translates in highly controlled investment towards mycobiont, that could explain the wide range of colonization patterns according to plant species affordability to sustain the mutualism when carbohydrates are required to be retained in storage organ. Following microscopic examination of roots collected at anthesis from UASVM Cluj Agro-Botanical Garden, highest intensity for root colonization in root segments was found in Dahlia variabilis followed by Helianthus tuberosus and Lilium candidum and lowest in Hemerocallis fulva and Gladiolus × grandiflorus. Arbuscules richness varied strongly among species. This study documents for the first time the level of arbuscular mycorrhizae in some summer flowering geophytes from Cluj county, Romania. It is concluded that summer geophytes might be good model plants for ecology of endophytic relationship since are highly sensitive to any disbalance in carbon expenditure.