ENHANCED CARBON TRANSFER BETWEEN ONIONS INFECTED WITH A VESICULAR‐ARBUSCULAR MYCORRHIZAL FUNGUS

S ummary Carbon (C) transfer between onion plants was enhanced by vesicular‐arbuscular mycorrhizas formed by the fungus, Glomus etunicatus. By applying pentachloronitrobenzene (PCNB) to hyphae, C translocation to the root was reduced but not eliminated indicating that two transfer processes may be involved; namely, cytoplasmic translocation within hyphae and mass flow along hyphal walls. Most of the transferred C remained in the roots; little or no C was translocated to the shoots. Therefore, it is uncertain whether C was released to the recipient plant or retained in fungal tissue.