On-farm production and utilization of arbuscular mycorrhizal fungus inoculum

Abstract

. 2005. On-farm production and utilization of arbuscular mycorrhizal fungus inoculum. Can. J. Plant Sci. 85: 15-21. Arbuscular mycorrhizal (AM) fungi colonize the roots of the majority of crop plants, forming a symbiosis that potentially enhances nutrient uptake, pest resistance, water relations, and soil aggregation. Inoculation with effective isolates of AM fungi is one way of ensuring the potential benefits of the symbiosis for plant production. Although inocula are available commercially, on-farm production of AM fungus inoculum would save farmers the associated processing and shipping costs. In addition, farmers could produce locally adapted isolates and generate a taxonomically diverse inoculum. On-farm inoculum production methods entail increasing inoculated isolates or indigenous AM fungi in fumigated or unfumigated field soil, respectively, or transplanting pre-colonized host plants into compost-based substrates. Subsequent delivery of the inoculum with seed to the planting hole in the field presents technological barriers that make these methods more viable in labor-intensive small farms. However, a readily available method for utilization of these inocula is mixing them into potting media for growth of vegetable seedlings for transplant to the field. Direct application of these inocula to the field and transplant of seedlings precolonized by these inocula have resulted in enhanced crop growth and yield. Les mycorhizes à arbuscules (MA) colonisent les racines de la majorité des végétaux. Ces champignons vivent en symbiose avec la plante, améliorant l'absorption des éléments nutritifs, la résis-tance aux ravageurs, l'utilisation de l'eau et l'agrégation des sols. L'inoculation de bons isolats de MA est une façon de veiller à ce que les bienfaits de cette symbiose profitent à la production agricole. Bien qu'on vende des inoculums sur le marché, leur pré-paration à la ferme permettrait à l'agriculteur d'économiser les frais de conditionnement et d'expédition. L'agriculteur pourrait aussi produire des isolats adaptés aux conditions locales et obtenir un inoculum de composition variée sur le plan taxonomique. La production d'inoculums à la ferme suppose un accroissement du nombre d'isolats ou de MA indigènes inoculés dans le sol des champs fumigés ou pas, respectivement, ou la transplantation de plantes hôtes déjà colonisées dans un substrat enrichi de compost. L'administration d'inoculum avec la semence à la plantation soulève des obstacles techniques qui rendent cette méthode plus rentable dans les petites exploitations faisant appel à une main-d'oeuvre abondante. Toutefois, le mélange de l'inoculum au milieu d'empotage dans lequel pousseront les plantules repiquées par la suite en pleine terre est une méthode aisément disponible. L'application directe de l'inoculum au sol et le repiquage de plantules colonisées ont abouti à une meilleure croissance et à un rendement plus important des cultures.

Potential of Cover Crops in Promoting Mycorrhizal Diversity and Soil Quality in Organic Farms

“…The beneficial effects of cover crops on mycorrhizal fungi have been well documented (Galvez et al, 1995;Boswell et al, 1998;Douds et al, 2005). This study confirmed the potential of warm seasoncover crops in promoting native mycorrhizal fungi in subtropical organic farms.…”

Salmonella and Escherichia coli O157:H7 Survival in Soil and Translocation into Leeks (Allium porrum) as Influenced by an Arbuscular Mycorrhizal Fungus (Glomus intraradices)

“…Consequently, modern agriculture is in need of alternatives to (i) reduce negative environmental impacts of conventional chemical inputs and (ii) enhance crop production efficiency. One proven biosustainable alternative is naturally occurring arbuscular mycorrhizal (AM) fungi, which are obligate symbionts that establish a mutualistic relationship with most crop plants (33)(34)(35). The fungus receives fixed carbon in the form of hexose from the host root and, in exchange, supplies the root with mineral nutrients, notably phosphorus, zinc, and copper.…”

Prospects for the use of multi-component symbiotic systems of the Legumes

“…One of the major constrains for this method is the necessity of large amounts of inoculum, which means the significant inputs for its transportation to the place of use. Thus, it seems to be expedient to utilize the local manufactures of inoculum (Onfarm production) organized in the proximity to final consumers (Douds et al, 2005). In addition, many inoculum producers still develop formulations using different AMF, which are quite often not well characterized in terms of ecological, soil, host or pathogen requirements.…”