Differential responses to nitrogen form and concentration for Oryzopsis hymenoides and Elymus lanceolatus

Authors

Robert S. Nowak, University of Nevada–Reno, Reno, Nevada
Cheryl L. Nowak, Intermountain Forest and Range Experiment Station, U.S. Forest Service, Reno, Nevada
Jay E. Anderson, Idaho State University, Pocatello, Idaho

Abstract

In a greenhouse experiment, effects of nitrogen form and concentration on productivity and dry matter allocation differed between two species native to semiarid ecosystems of the Great Basin. Aboveground production of green surface area and of dry matter were consistently enhanced by increased nitrogen for the rhizomatous grass Elymus lanceolatus, but not for the bunchgrass Oryzopsis hymenoides. These differences were likely due to inherently low growth rates of O. hymenoides. Aboveground dry matter allocation also differed between the two species. O. hymenoides had more leaves per tiller with increased nitrogen, whereas leaf size but not number increased for E. lanceolatus. Furthermore, increases in tiller density with increased nitrogen for E. lanceolatus were almost three times greater than those for O. hymenoides. E. lanceolatus, but not O. hymenoides, was sensitive to the form of nitrogen supplied to the plants. When NH₄–N was the only form of nitrogen supplied, high concentrations of NH₄–N inhibited aboveground production of E. lanceolatus.

Recommended Citation

Nowak, Robert S.; Nowak, Cheryl L.; and Anderson, Jay E. (1993) "Differential responses to nitrogen form and concentration for Oryzopsis hymenoides and Elymus lanceolatus," Great Basin Naturalist: Vol. 53: No. 3, Article 2.
Available at: https://scholarsarchive.byu.edu/gbn/vol53/iss3/2