Utah lotus: North American legume for rangeland revegetation in southern Great Basin and Colorado Plateau

Authors: STETTLER, JASON - Utah State University; Johnson, Douglas; Bushman, Shaun; Connors, Kevin; Jones, Thomas; MACADAM, JENNIFER - Utah State University

Submitted to: Rangeland Ecology and Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/6/2016
Publication Date: 7/3/2017
Citation: Stettler, J.M., Johnson, D.A., Bushman, B.S., Connors, K.J., Jones, T.A., MacAdam, J.W. 2017. Utah lotus: North American legume for rangeland revegetation in southern Great Basin and Colorado Plateau. Rangeland Ecology and Management. 70(6):691-699. https://doi.org/10.1016/j.rama.2017.06.002.
DOI: https://doi.org/10.1016/j.rama.2017.06.002

Interpretive Summary: North American legumes are critical for rangeland restoration because they diversify planting mixtures, enhance pollinator options, provide high quality forage for livestock and wildlife, and expand habitats for insects that are important for diets of sage grouse chicks. We made seed collections of Utah lotus and scrub lotus in Nevada, Utah, and Arizona and evaluated them at three common gardens in northern Utah. We found that 14 collections from Nevada and Utah and Nevada were Utah lotus, and five collections from Arizona were scrub lotus. Collections differed in all plant characteristics measured. Two collections of Utah lotus (LU-5 and LU-20) were among the best performing collections for dry-matter yield, pod production, number of stems, canopy height, and survival. Based on our results, these two collections should be used to develop a plant material of Utah lotus for rangeland revegetation in Utah and Nevada.

Technical Abstract: Utah lotus (Lotus utahensis Ottley) is a North American leguminous forb that may hold promise for rangeland revegetation in the western USA for diversifying planting mixtures, attracting pollinators, providing high quality forage, and expanding habitats for insects needed by sage grouse chicks. We evaluated 19 purported Utah lotus seed collections originating from Nevada, Utah, and Arizona for genetic variation of phenotypic traits and genetic relationships. Taxonomic verification of the collections indicated that 14 collections were Utah lotus and five collections from Arizona were scrub lotus (L. wrightii [A. Gray] Greene). Spring emergence date, flowering date, survival, dry-matter yield, and canopy width discriminated Utah lotus and scrub lotus with 100% accuracy. Population structure estimates defined by 552 AFLP markers partitioned accessions into three primary groups: Utah lotus, scrub lotus, and a L. corniculatus check. Within the Utah lotus collections, we identified three subgroups, which corresponded to their geographic origin. Two collections of Utah lotus (LU-5 and LU-20) were among the top-performing collections for the phenotypic traits examined, including dry-matter yield, pod production, number of stems, canopy height, and persistence. No significant Pearson's correlations or canonical correlations were observed among the phenotypic traits and environmental characteristics at the collection sites. Significant correlations were detected between genetic and geographic, and phenotypic and geographic distance matrices (r = 0.89, P = 0.001 and r = 0.24, P = 0.04, respectively). Condensed tannin (CT) contents of Utah lotus and scrub lotus were high (142 to 199 g kg-1), which may be of interest in legume breeding programs where selection for high CT may be desirable for reducing bloat risk. Based on our phenotypic and genotypic evaluations, one pooled germplasm source of Utah lotus comprising collections LU-5 and LU-20 could be developed for use in rangeland revegetation in the southern Great Basin and Colorado Plateau.