Spatial Pattern Analysis of Plant-Parasitic Nematodes
Abstract
Spatial patterns of Meloidogyne incognita, Tylenchorhynchus claytoni, Helicotylenchus dihystera, and Criconemella ornata were analyzed using Hill's two-term local quadrat variance method (TTLQV), spectral analysis, and spatial correlation. Data were collected according to a systematic grid sampling plan from seven tobacco fields in North Carolina. Different estimates of nematode cluster size were obtained through TTLQV and spectral analysis. No relationship was observed between either estimate and nematode species, time of sampling (spring vs. fall), or mean density. Cluster size estimates obtained from spectral analysis depended on sampling block size. For each species examined, spatial correlations among nematode population densities were greater within plant rows than across rows, indicating that clusters were ellipsoidal with long axes oriented along plant rows. Analysis of mean square errors indicated that significant gains in sampling efficiency resulted from orienting the long axis of sampling blocks across plant rows. Spatial correlation was greater in the fall than in spring and was greater among 1 × 1-m quadrats than among 3 × 3-m quadrats. Key words: nematode distribution, spatial pattern, sampling design.Downloads
Published
Issue
Section
License
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).
