Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Doctorat → États-Unis → 2021 → Mycorrhizal Fungi on the Sagebrush Steppe : Benefits for Restoring Keystone Rangeland Plant Species

Oregon State University (2021)

Mycorrhizal Fungi on the Sagebrush Steppe : Benefits for Restoring Keystone Rangeland Plant Species

Prado-Tarango, David E.

Titre : Mycorrhizal Fungi on the Sagebrush Steppe : Benefits for Restoring Keystone Rangeland Plant Species

Auteur : Prado-Tarango, David E.

Université de soutenance : Oregon State University

Grade : Doctor of Philosophy (Ph.D.) 2021

Résumé partiel
Arbuscular mycorrhizal fungi (AMF) are plant symbionts that associate with the vast majority of terrestrial plants species. The AMF colonizes the plant roots by penetrating the root cortical cells, where the fungi exchanges mineral nutrients with the host plant for photosynthates. This association exists as a complex system in which both partners are expected to gain benefits. Such benefits eventually have cascading effects on the soil and plant communities. Furthermore, AMF can be inoculated as a management tool, and it has been used as a tool for ecological restoration on multiple ecosystems such as grasslands, forests and recently on rangelands. However, AMF inoculation of rangeland plant species is conducted without a clear understanding of their AMF interactions and effects. The goal of this dissertation is to enhance the understanding of the relationship between AMF and different important rangeland plant species. There is a lack of information for multiple valuable rangeland plant species regarding AMF interactions, this research is intended to be a starting point. We want to better understand how AMF can be used as a management tool for restoration programs in rangelands such as the sagebrush steppe. The objectives of this study were : 1) to elucidate the effects of a commercial AMF inoculum on the growth of Artemisia tridentata ssp. wyomingensis, A. arbuscula, A. nova and Taeniatherum caput-medusae ; 2) to evaluate the effect of a commercial AMF inoculum on biotic (interspecific competition from the invasive species T. caput-medusae) and abiotic (drought) stress amelioration on the sagebrush steppe plants A. tridentata ssp. wyomingensis, A. arbuscula, and A. nova ; 3) to evaluate the mycorrhizal responsiveness and growth responses of T. caput-medusae, Ventenata dubia and Pseudoroegneria spicata to 3 different sources of AMF inoculum and biochar ; and 4) to assess the bacterial diversity and abundance in a fire-disturbed sagebrush steppe ecosystem important for Purshia tridentata restoration. We conducted a controlled greenhouse experiment to test if a commercial AMF inoculum could colonize and provide benefits to A. tridentata ssp. wyomingensis, A. arbuscula, A. nova and T. caput-medusae in sterile and live soil. We measured inoculum effects on root colonization means and biomass production. Inoculum viability was first confirmed using Trifolium incarnatum as a host. However, inoculum did not colonize the Artemisia or T. caput-medusae species. AMF colonization occurred in live soil only as it contained enough propagules

Présentation

Version intégrale

Page publiée le 25 janvier 2023