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

Accueil du site → Master → Etats Unis → 2011 → Restoration Strategies for a Native Perennial : Germination and Seedling Physiology of Sphaeralcea Munroana

University of Idaho (2011)

Restoration Strategies for a Native Perennial : Germination and Seedling Physiology of Sphaeralcea Munroana

Kildisheva Olga A

Titre : Restoration Strategies for a Native Perennial : Germination and Seedling Physiology of Sphaeralcea Munroana

Auteur : Kildisheva Olga A

Université de soutenance : University of Idaho

Grade : Mastor of Science 2011

Résumé
The Great Basin region of the western United States has undergone significant disturbance and fragmentation because of overgrazing for livestock production, disruption of the natural fire regimes, and the introduction of non-native species. At present, habitat loss greatly surpasses the rate of system recovery, making restoration integral to ecosystem function and resilience. To date, restoration research and practice have focused largely on keystone plant species, however, to be effective, restoration must include myriad plant forms and guilds. Munro’s globemallow (Sphaeralcea munroana (Douglas) Spach) is a perennial, cool-season forb, endemic to the Great Basin that serves as an important host for native pollinators, provides soil stabilization, and is a source of food for numerous mammals. For these reasons, as well as its ability to tolerate disturbance, temperature extremes, and drought, it is an important candidate for broad scale ecosystem restoration across its native range. Little information regarding seed germination and seedling establishment is available for Munro’s globemallow, and what does exist is synthesized in the first chapter of this thesis. The second chapter is a detailed examination of the seed dormancy mechanisms. The results of 4 experiments identified physical dormancy, which inhibits water imbibition, to be responsible for poor germination. Seed coat scarification is essential for germination and can be achieved through mechanical or boiling water scarification. The third chapter of this thesis describes an experiment conducted to evaluate a suite of morphological and physiological responses of Munro’s globemallow to a range of temperature and moisture conditions during seedling establishment. Results indicate that seedlings are able to tolerate drought and relative high temperature conditions early in their establishment, however, low temperatures substantially limited seedling development ; thus, a later sowing date may optimize plant establishment. Overall, nursery production, seed increase projects, and outplanting success of Munro’s globemallow should be improved through the incorporation of the results of this thesis.

Version intégrale

Page publiée le 22 novembre 2013, mise à jour le 9 mars 2019