A Viewpoint on Indian Ricegrass Research: Its Present Status and Future Prospects

Abstract

Indian ricegrass (Oryzopsis hymenoides (Roem. & Schult.) Ricker) is adapted to sandy arid areas of much of the western USA and is a highly desirable species on winter range sites. Seed is typically highly dormant. Mechanical dormancy has been reduced by mechanical and sulfuric acid scarification, and physiological dormancy has been reduced with stratification, giberellic acid, and kinetin. A better understanding of the relationship between mechanical and physiological dormancy may lead to a practical procedure for breaking dormancy in harvested seed. Alternatively, a better understanding of environmental factors on seed production may lead to production of already low dormancy seed. Establishment success will also depend on development of appropriate seedbed management practices for various soils. Reduction of the currently large shattering losses would have a favorable impact on the economics of Indian ricegrass seed production. An interdisciplinary approach including seed physiology, seedbed ecology, seed technology, and plant breeding can potentially solve these problems. The potential of seeding Indian ricegrass for improving rangelands can only be realized after low dormancy seed becomes available, appropriate seedbed management practices are developed, and seed shattering losses are reduced.