Application of arbuscular mycorrhizal fungi on the production of cut flower roses under commercial-like conditions

Abstract

The objective of this work was to study the influence of two arbuscular mycorrhizal fungi (AMF) - Glomus mosseae (Nicol. & Gerd.) Gerd. & Trappe, and G. intraradices (Schenck & Smith) - on cut flower yield of rose (Rosa hybrida L. cv. Grand Gala) under commercial-like greenhouse conditions. Flower production was positively influenced by G. mosseae inoculation. Both inocula tested caused low levels of mycorrhizal root colonization, with higher percentages in Rosa associated with G. mosseae. Significant improvement of plant biomass or leaf nutritional status was not detected in inoculated plants probably due to the low symbiosis establishment. However, G. mosseae induced an early flowering and slightly increased number of cut flowers relative to non-mycorrhizal controls. It is suggested that an altered carbohydrate metabolism could contribute to this positive effect. Low colonization of rose roots supports the idea that more effort is required to ensure successful application of AMF in ornamental production systems.