TY - JOUR

T1 - Benomyl inhibits phosphorus transport but not fungal alkaline phosphatase activity in a Glomus–cucumber symbiosis

AU - Larsen, John

AU - Thingstrup, Ida

AU - Jakobsen, Iver

AU - Rosendahl, Søren

N1 - KEYWORDS Arbuscular mycorrhiza. hyphal P transport • alkaline phosphatase • benomyl

PY - 1996

Y1 - 1996

N2 - Short-term effects of benomyl on the arbuscular mycorrhizal fungus Glomus caledonium (Nicol. & Gerd.) Trappe and Gerdeman associated with Cucumis sativus L. were studied by measuring effects on fungal P transport and on fungal alkaline phosphatase activity. Mycorrhizal plants were grown in three compartment systems where nylon mesh was used to separate n root-free hyphal compartment (HC) and a root + hyphal compartment(RHC) from The main root compartment (RC). Non-mycorrhizal control plants were grown in similar growth units. After 6 wk benomyl was applied to the plants in three ways: as soil drenches to RHC or HC, or as u spray to the leaves. Benomyl was added in three concentrations. Equal amounts of 32P and 33P were added to the HC and to the RHC respectively, immediately after the application of benomyl. Plants were harvested 4–6 d later. Hyphal transport of 32P from the HC was inhibited when benomyl was applied to the HC at 10 µg g-1 soil, whereas the uptake of 32P from RHC I roots + hyphae) was reduced only at the highest dose of application to the RHC (100 µ g g-1 soil). In contrast to the marked reduction of benomyl on fungal P transport, the activity of fungal alkaline phosphatase inside the roots was unaffected by benomyl.

AB - Short-term effects of benomyl on the arbuscular mycorrhizal fungus Glomus caledonium (Nicol. & Gerd.) Trappe and Gerdeman associated with Cucumis sativus L. were studied by measuring effects on fungal P transport and on fungal alkaline phosphatase activity. Mycorrhizal plants were grown in three compartment systems where nylon mesh was used to separate n root-free hyphal compartment (HC) and a root + hyphal compartment(RHC) from The main root compartment (RC). Non-mycorrhizal control plants were grown in similar growth units. After 6 wk benomyl was applied to the plants in three ways: as soil drenches to RHC or HC, or as u spray to the leaves. Benomyl was added in three concentrations. Equal amounts of 32P and 33P were added to the HC and to the RHC respectively, immediately after the application of benomyl. Plants were harvested 4–6 d later. Hyphal transport of 32P from the HC was inhibited when benomyl was applied to the HC at 10 µg g-1 soil, whereas the uptake of 32P from RHC I roots + hyphae) was reduced only at the highest dose of application to the RHC (100 µ g g-1 soil). In contrast to the marked reduction of benomyl on fungal P transport, the activity of fungal alkaline phosphatase inside the roots was unaffected by benomyl.

U2 - 10.1111/j.1469-8137.1996.tb04518.x

DO - 10.1111/j.1469-8137.1996.tb04518.x

M3 - Journal article

VL - 132

SP - 127

EP - 133

JO - New Phytologist

JF - New Phytologist

SN - 0028-646X

IS - 1

ER -