HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Campbell, T. A. Articles by Xia, Z. L. Search for Related Content PubMed Articles by Campbell, T. A. Articles by Xia, Z. L. Agricola Articles by Campbell, T. A. Articles by Xia, Z. L.

Agronomic Evaluation of Medicago ruthenica Collected in Inner Mongolia

Soybean and Alfalfa Research Lab., USDA-ARS, Beltsville Agric. Res. Center, Beltsville MD 20705-2350
Grassland Res. Inst., Chinese Academy of Agricultural Sciences, Wulanchabu East Street, Hunhot, Inner Mongolia 010010, PRC
Institute of Soil and Fertilization, Chinese Academy of Agricultural Sciences, 30 Baishiqiao Road, Beijing 100081, PRC

^* Corresponding author (E-mail: acampbel{at}asrr.arsusda.gov).

Medicago ruthenica (L.) Ledebour has long been recognized as a potential new forage crop, which may also have potential as a source of genes for improving abiotic stress tolerance in cultivated alfalfa (M. sativa L.). This study was designed to assess the genetic variation among 50 M. ruthenica accessions, collected in Inner Mongolia in 1991 from 15 environments ranging from sand dunes to lush grassland, and to assess the agronomic potential of the species in the humid eastern USA. Accessions were evaluated in the field at Beltsville, MD, in 1993 and 1994 on an luka sandy loam (coarse-loamy, siliceous, acid, thermic, Aquic Udigluvent; pH 6.4) in boron and potassium deficient soil. Stand retention was only 47% (compared with 94% for M. sativa checks) after the winter of 1993, indicating that the species is not well adapted to the humid eastern USA. Significant variation was noted for reaction to environmental stress (possibly boron deficiency), days from seeding to tillering, dry matter yield, growth habit, leaf shape, and plant height and width. No disease symptoms were noted; however, a detailed pathological examination was not conducted. A positive relationship was noted between plant width and yield, and between uprightness and narrow leaves. The more procurebent plants with broader leaves may have been less susceptible to winter damage under Beltsville conditions. Some of the most agronomicaily desirable accessions could have resulted from genetic shifts due to selection. Analyses indicate that M. ruthenica may have the potential to become a new forage crop, perhaps for low input systems, and that semi-erect (for hay production) or procumbent (grazing tolerant) populations with improved seedling vigor and yield could be developed. Considering the antiquity and isolation of M. ruthenica, its harsh native environment, and the stress tolerance and yield of elite accessions under low-input conditions, M. ruthenica may provide genes that could be of considerable value to cultivated alfalfa.

Received for publication December 6, 1995.