Impact of Multi-year Cropping Regimes on Solanum tuberosum Tuber Yields in the Presence of Pratylenchus penetrans and Verticillium dahliae
AbstractFive cropping regimes involving combinations of 2 legumes, alfalfa (Medicago sativa) and yellow sweet dover (Melilotus officinalis), 2 monocots, corn (Zea mays) and sudax (Sorghum halupeuse × Sorghum sudanese), and potato (Solanum tuberosum cv. Superior) were tested for their impact on potato yields in a field infested with Pratylenchus penetrans and Verticillium dahliae. No differences in 1990 tuber yields were observed among the five cropping regimes (P 0.05). In 1991, yields following 1 year of corn, sudax, sweet clover, or alfalfa and 2 years of potato were not different from that of 3 years of continuous potato (P 0.05). Two years of sweet clover or alfalfa followed by potato resulted in significantly increased potato tuber yields compared with 3 years of potato (P 0.05). The 2-year legume and 2-year grain rotations resulted in lower P. penetrans population densities at the end of the 3-year rotation compared with 3 years of continuous potato (P 0.01). The highest preplant V. dahliae population density (34 cfu/g soil), together with a P. penetrans density of 12/100 cm³ of soil was in the sudax-sudax-potato cropping regime and resulted in the lowest potato tuber yield. The highest preplant P. penetrans population density (54/100 cm³ soil), together with a V. dahliae population density of 19.5 cfu/g soil was observed in the corn-corn-potato cropping regime and resulted in the second lowest potato tuber yield in 1991. After 3 years, potato tuber yields were negatively related to preplant densities of V. dahliae (r² = 0.237), P. penetrans (r² = 0.175), and both pathogens (r² = 0.380). A comprehensive regression model was developed to isolate pathogen effects on potato yields from cropping regime effects encompassing all 10 cropping regimes (r² = 0.915). Key words: cropping regime, interaction, nematode, potato tuber yield, Pratylenchus penetrans, lesion nematode, Solanum tuberosum, Verticillium dahliae, verticillium wilt.
Copyright and Permissions
All material published by the Society of Nematologists (SON), except for papers prepared by United States and Canadian government employees, is copyrighted and protected under the U.S. copyright law. Under the Copyright Act of 1976, the term of copyright for materials registered by an organization is 75 years from the date first published. Before publishing any manuscript, SON requires that authors transfer full and complete ownership of any copyright to SON by signing a JON Page Charge/Copyright Form (.pdf). SON then registers the copyright. Subsequent use of published materials requires written permission from the SON and may be obtained by contacting the current Editor-in-Chief and state where and how the material will be used.
The author warrants that the article is an original work not published elsewhere in whole or in part, except in abstract form, and that the author has full power to make this grant. If portions of the article have been published previously, then the author warrants that permission has been obtained from the copyright holder and the author will submit a copy of the permission release with this copyright transfer form.
SON shall claim no proprietary right other than copyright. Authors and coauthors retain the right to revise, adapt, modify, or otherwise use all or part of the article in future works of the author(s), such as press releases, lectures, and reviews, provided that all such use is for the personal noncommercial benefit of the author(s). All patent rights are retained by the author(s).