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

This Article Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Seguin, P. Articles by Swanson, D. R. Search for Related Content PubMed Articles by Seguin, P. Articles by Swanson, D. R. Agricola Articles by Seguin, P. Articles by Swanson, D. R. Related Collections Alfalfa Production Agriculture

PRODUCTION PAPER

Alfalfa Autotoxicity

Effects of Reseeding Delay, Original Stand Age, and Cultivar

^a Dep. of Plant Sci., McGill Univ., Macdonald Campus, 21111 Lakeshore Rd., Ste. Anne-de-Bellevue, QC H9X 3V9, Canada
^b Dep. of Agron. and Plant Genet., Univ. of Minnesota, 1991 Buford Circle, 411 Borlaug Hall, St. Paul, MN 55108-6026
^c Dep. of Soil, Water, and Climate, Univ. of Minnesota, 1991 Buford Circle, 439 Borlaug Hall, St. Paul, MN 55108-6028
^d USDA-ARS, U.S. Dairy Forage Res. Cent. (Minnesota cluster) and Dep. of Soil, Water, and Climate, Univ. of Minnesota, 1991 Buford Circle, St. Paul, MN 55108-6028
^e Southern Res. and Outreach Cent., 35838 120th Street, Waseca, MN 56093-4521
^f Southwest Res. and Outreach Cent., P.O. Box 428, Lamberton, MN 56152

* Corresponding author (sheaf001{at}tc.umn.edu)

Received for publication May 30, 2001. Autotoxicity may reduce plant population and productivity of alfalfa (Medicago sativa L.) reseeded into winterkilled alfalfa stands; however, the interaction of important variables such as reseeding delay, stand age, and cultivar with autotoxicity has not been evaluated. We determined the effects of stand age (1-, 2-, or 3-yr-old alfalfa stands), reseeding delay (none or 2-wk delay) after plowing the original stands in May, and cultivar reseeded (‘5262’ or ‘Wrangler’) on populations and productivity of reseeded alfalfa. Oat (Avena sativa L.), corn (Zea mays L.), or tall fescue (Festuca arundinaceae Schreb.) served as controls. There was no consistent evidence for autotoxicity in the reseeding year, as populations and forage yields were similar when seeding followed alfalfa or the control crops, regardless of the age of the previous alfalfa stand or the alfalfa cultivar reseeded. Delaying seeding had inconsistent effects on alfalfa plant population but consistently reduced yields in the seeding year, with yields averaging 4.9 and 6.3 Mg ha^-1 with and without a 2-wk reseeding delay, respectively. In three of six experiments, yields at the first harvest in the year following reseeding averaged 15% lower following alfalfa than a control crop (3.6 and 4.2 Mg ha^-1, respectively), suggesting that alfalfa autotoxic response may be delayed. The lack of consistent evidence of autotoxicity, coupled with yield reductions in the seeding year associated with delayed seeding, suggest that the recommendation to delay alfalfa reseeding 2 wk following plowing of winterkilled stands may be unjustified.

This article has been cited by other articles:

				S.-U. Chon, C. J. Nelson, and J. H. Coutts Osmotic and Autotoxic Effects of Leaf Extracts on Germination and Seedling Growth of Alfalfa Agron. J., November 1, 2004; 96(6): 1673 - 1679. [Abstract] [Full Text] [PDF]