Full Length Research Paper

Development of an in vitro culture system adapted to banana mycorrhization

Marie Chantal Koffi¹, Ivan Enrique de la Providencia¹, Annemie Elsen² and Stéphane Declerck¹*

1Université catholique de Louvain (UCL), Unité de microbiologie, Place croix du Sud 3, 1348 Louvain-la-Neuve, Belgium.

2Laboratory of Tropical Crop Improvement; Division of Crop Biotechnics, Faculty of Bioscience Engineering, K. U. Leuven, Kasteelpark Arenberg 13, 3001 Leuven, Belgium.

*Corresponding author. E-mail: stephan.declerck@uclouvain.be. Tel.: + 32 (10) 47 46 44. Fax: +32 (10) 45 15 01.

Abbreviations: AM, Arbuscular mycorrhizal; BCA, biological control agent; MSR, modified Strullu Romand.

Accepted 6 March, 2009

The beneficial impact of arbuscular mycorrhizal (AM) fungi on banana nutrition and resistance against abiotic and biotic stresses is well documented. However, most studies were conducted under greenhouse or field conditions and none reported the life cycle of the AM fungi on banana roots. It is obvious that any system associating both organisms under strict controlled in vitro culture conditions may help to comprehend the role of AM fungi in banana physiology. Here we developed an in vitro culture system associating autotrophic micropropagated banana plants with an AM fungus (Glomus intraradices). Intraradical root colonization, with production of arbuscules and vesicules, as well as extraradical development with production of new spores was observed. This study opens the door to investigate the role of AM fungi in banana physiology in particular for the control (through e.g. the elicitation of defence genes in bananas) of major banana root pathogens under strict in vitro culture conditions.

Key words: Arbuscular mycorrhizal fungi, Musa acuminata, in vitro conditions, sporulation.