Western North American Naturalist Volume 65 Number 2 Article 14 4-29-2005 Nutrient relationships between Orobanche fasciculata Nutt. and its host Artemisia pygmaea Gray in the Uinta Basin of Utah, USA Jack D. Brotherson Brigham Young University Brenda T. Simmons Gilbert, Arizona Terry Ball Brigham Young University W. Ralph Anderson Brigham Young University Follow this and additional works at: https://scholarsarchive.byu.edu/wnan Recommended Citation Brotherson, Jack D.; Simmons, Brenda T.; Ball, Terry; and Anderson, W. Ralph (2005) "Nutrient relationships between Orobanche fasciculata Nutt. and its host Artemisia pygmaea Gray in the Uinta Basin of Utah, USA," Western North American Naturalist: Vol. 65 : No. 2 , Article 14. Available at: https://scholarsarchive.byu.edu/wnan/vol65/iss2/14 This Article is brought to you for free and open access by the Western North American Naturalist Publications at BYU ScholarsArchive. It has been accepted for inclusion in Western North American Naturalist by an authorized editor of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. Western North American Naturalist 65(2), © 2005, pp. 242–247 NUTRIENT RELATIONSHIPS BETWEEN OROBANCHE FASCICULATA NUTT. AND ITS HOST ARTEMISIA PYGMAEA GRAY IN THE UINTA BASIN OF UTAH, USA Jack D. Brotherson1,3, Brenda T. Simmons2, Terry Ball4, and W. Ralph Anderson1 ABSTRACT.—Patterns of mineral nutrient uptake and distribution within the roots, stems, and leaves of Artemisia pyg- maea and in the vascular parasite Orobanche fasciculata were investigated. All nutrients studied were magnified over concentrations found in the soil into the host and parasite. Nitrogen, phosphorus, potassium, and zinc were magnified along the flow gradient of soil-roots-stems-leaves of the host. All others increased in the roots and then decreased in the stems and leaves. Orobanche fasciculata concentrated phosphorus, potassium, and sodium over soil and root concentra- tions while excluding to some degree all others. Key words: Orobanche fasciculata, Artemisia pygmaea, mineral nutrient uptake, host and parasite interaction. Orobanche fasciculata Nutt. (clustered can have primary and secondary haustoria, the broomrape or clustered cancerroot) belongs to former located where the shoot of the parasite the Orobanchaceae or broomrape family, mem- emerges and the latter where the roots from bers of which are parasitic on the roots of the parasite attach to the roots of the host. Par- flowering plants (Reuter 1986, Welsh et al. 1993, asites that develop more advanced haustoria Wolfe and dePamphilis 1997). The genus have little or no root system. Such is the case Orobanche contains over 100 species (Parker with O. fasciculata (Kuijt 1969). The main pur- and Riches 1993), all of which are annual or pose of the haustorium is uptake of water, monocarpic (Kuijt 1969), obligate, herbaceous organic compounds, and mineral nutrients from parasites (Parker and Riches 1993). Orobanche the host plant. fasciculata parasitizes a variety of host species, Orobanche species are found in over 58 especially species of Artemisia (Welsh et al. countries, with some species having large pop- 1993). It is purplish to yellowish in color and ulations in areas of intensive agriculture (Jor- grows in a split stem to between 5 cm and 10 dan and Nile River valleys) and other species cm above the soil surface (Welsh et al. 1993). being endemic to small, localized areas (Sauer- Seeds of Orobanche spp. germinate after born 1991). Generally, they grow in infertile being stimulated chemically from 1 to 2 weeks soils, such as the alkaline soils of the Middle by exudates from the host’s root (Sauerborn East. Few Orobanche species grow in acidic 1991, Parker and Riches 1993). Upon germi- soils, as the lower pH causes the seeds to ger- nation Orobanche seed develops a radicle that minate at distances so far from the host that grows in the direction of the chemical stimuli contact between parasite seedling and host of the host’s root. This distance is generally root is not accomplished, thus resulting in the not more than a few centimeters from the seedling’s eventual death (Parker and Riches Orobanche seed. Once the radicle reaches the 1993). Most Orobanche species are found in the host root, a haustorium (that part of the para- Mediterranean region with its characteristic site that grows inside the host) is produced, climate, but are also found in humid, subtropi- which attaches the Orobanche seedling to the cal, arid, semiarid, and temperate climates. They host. The haustorium is also the site where the are associated with both irrigated and nonirri- bud and shoot of the parasite emerge and gated lands (Sauerborn 1991). Orobanche fasci- elongate (Parker and Riches 1993). A parasite culata is endemic to North America, ranging 1Department of Integrative Biology, Brigham Young University, Provo, UT 84602. 2275 West Juniper Avenue #1073, Gilbert, AZ 85233. 3Corresponding author: 435 WIDB, Department of Integrative Biology, Brigham Young University, Provo, UT 84602. 4Department of Ancient Scripture, Brigham Young University, Provo, UT 84602. 242 2005] NUTRIENT DYNAMICS BETWEEN OROBANCHE AND ARTEMISIA 243 in distribution from the Yukon Territory, south of Hill Creek. The study site covers 0.8–1.2 ha to Mexico, east to Michigan, and west to Cali- and is located on highly clay loam Green fornia. Within this range, O. fasciculata is asso- River shale soils underlain by fractured sand- ciated with sand dune ecosystems, arid shrub- stone layers called Hill Creek Rock, which has lands and grasslands, pinyon/juniper wood- been mined and used as ornamental building lands, aspen, and fir communities up to 3260 m material. Artemisia pygmaea is the dominant in elevation (Reuter 1986, Welsh et al. 1993). shrub on the site, although its population den- However, O. fasciculata is an uncommon spe- sities are low. Low-growing shrubs and grasses cies. As such, several states have listed it as including Eriogonum corymbosum, Elymus spi- rare (Indiana and the province of Ontario), catus, Atriplex confertifolia, Stipa, hymenoides, threatened (Wisconsin and Michigan), and even and Artemisia tridentata dominate areas adja- endangered (Illinois; Sheviak 1978, Bacone cent to the study area (Brotherson 1967). and Hedge 1980, Argus and White 1982, Soils are shallow, sandy clay loams, residual Brynildson and Alverson 1982, Beaman et al. in nature, sandstone based, and rocky. Calcare- 1985). No listing of O. fasciculata as threat- ous and basic, they contain elevated levels of ened or endangered is known in Utah. soluble salts in the upper 46 cm of the soil Other than taxonomic studies, little research profile. Clay increases with depth to 15 cm has been done on O. fasciculata. Reuter (1986) and then decreases. Cation exchange capacity studied the habitat and reproductive ecology ranges from 20 to 25 meq per 100 grams of of O. fasciculata in a sand dune ecosystem in soil and increases with depth. Calcium, potas- Wisconsin. She concluded that O. fasciculata sium, and sodium concentrations decrease with has the ability to reproduce parthenogeneti- depth while magnesium increases (Brotherson cally, that it produces many seeds which dis- 1967). Macronutrient concentrations are low perse across long distances and yet as a species (<215 ppm), with nitrogen, phosphorus, potas- would be considered uncommon, a fact thought sium, and sodium being the lowest. Micro- to be associated with parasite seed dispersal nutrients were more abundant than macro- and host growth dynamics. nutrients. Artemisia pygmaea Gray, or pygmy sage- The area receives between 30 and 40 cm of brush, is found in Arizona, Nevada, and Utah rain annually, 10–20 cm falling as snow from growing in shallow, infertile calcareous soils October to April and 10–20 cm from summer (Ward 1953). It has been collected in 13 coun- thunderstorms between May and September. ties from Utah’s desert and mountainous During the winter months temperature lows regions where it grows on clay loam soils asso- average between –18° and –16°C, while mean ciated with Green River shale, igneous and highs range from –2° to 0°C. In the summer calcareous gravels, and dolomitic outcrops or lower temperatures average 9° to 13°C and gravels (Welsh et al. 1993). A dwarf shrub the highs range from 27° to 31°C (Greer et al. (0.5–2 dm tall), A. pygmaea grows in patches 1981). and is not useful as browse (McArthur et al. The study site has had a grazing history of 1979). Welsh et al. (1993) indicate A. pygmaea primarily wild horses, mule deer, and rabbits. is often associated with rare plant species, such Occasional sheep and cattle grazing has also as O. fasciculata. occurred. The purpose of this study is to analyze the host-parasite relationships between A. pygmaea METHODS Gray and O. fasciculata Nutt. regarding nutrient Field Methods uptake and transfer between host and parasite on populations found in the Uinta Basin of Data were taken in August 1986 and 1987. Utah, USA. Data taken during 1986 reflect nutrient flows from the soil to A. pygmaea roots to O. fascicu- STUDY SITE lata. The 1987 samples include data taken to reflect nutrient flows from soil to roots to stems The study site is located 20.5 km (33 miles) and leaves of the host plants along with the south of Ouray, Utah, on the Ute Indian Reser- soil-root-parasite relationship. We collected a vation in Duchesne County. The site is on a total of 20 soil samples, 10 per year. Fifty-eight gentle 2%–3%, west-facing slope on the plateau plant samples were also collected during the 244 WESTERN NORTH AMERICAN NATURALIST [Volume 65 2-year study, 20 in 1986 and 38 in 1987. Those the means of each element to identify any that taken in 1986 include 10 of A. pygmaea roots varied significantly in concentration between and 10 of O.