ASTM E629-96

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ASTM E629 96 0759510 0583866 385
AMERICAN SOCIETY FOR TESTING AND MATERIALS
4fb Designation: E 629 - 96
100 Ban Harbor Dr. West Conshohocken. PA 19428
Reprinted hwn the Annual Book of ASTM Standards. Ccpyright ASTM
II not listed in the cuireni combined index. will appear in the next edition.
Standard Guide for
Field Evaluation of Nematode Control Agents-Determination
of Nematode Population Responses to Control Agents‘
This standard is issued under the fixed designation E 629; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (t) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
Chemical control agents are necessary for the efficient production of many crops. If nematicides
are to be tested and used properly, there must be a consensus of informed opinion on reliable,
standardized sampling procedures and extraction methods. In selecting extraction procedures,
special consideration must be given to target species and soil type. Regardless of methods used in
evaluating nematode responses to nematicides, results are no better than the weakest links of the
experiments. For nematode population data to be of value, soil samples must be collected at the
proper time in an appropriate probing pattern. Samples also must be handled properly after
collection, and the appropriate extraction procedure must be utilized.
No one method of collecting samples for nematode assay or method for extracting nematodes to
evaluate nematicides can be used in all situations. Therefore, the procedures presented in this
standard are presented only as a guide. However, specific procedures for sampling and extracting
nematodes are recommended for various combinations of different types of crops, soil textures,
sampling periods, and nematodes. If any of these procedures are to be utilized reliably in evaluating
responses to nematode control agents, investigators must be relatively familiar with the population
dynamics of the target nematode on the particular crop and the specific geographic region
involved. Procedures in the various methods for extracting nematodes are given in Sections 9
through 59 and in Tables 1 and 2.
In evaluating the efficacy of nematode control agents, characterization of population responses
of the target nematode species is as important as determining plant responses. Most nematicides
exert their maximum effect shortly after application, but long-term changes in soil biology often
occur. For example, the proportions of species in nematode communities often shiR after chemical
treatments of soil. In addition, some nematicides stimulate plant growth in the absence of
others affect insect, fungal, or bacterial populations, or a combination of these (2).
nematodes
See Task-Force report on “Evaluation of plant responses”, C. C. Om, Chairman; and “Interactions
with other pathogens and other pesticides”, G. A. Bergeson, Chairman.
The most important considerations in determining nematode population responses to nematode
control agents are the collection of representative soil or root samples, or both, from each plot or
field, adequate mixing of these samples, and extraction of nematodes by the procedure best suited
for a given experiment, target species, and soil type. Procedures used depend on the kinds and
numbers of nematodes present and their Characteristics and the nature and condition of the
samples, including soil texture and the time of collection. If nematode numbers are below a
detectable level, an appropriate bioassay may also be used.
1. Scope tests, and reporting of results.
1.3 This Standayd does not purport to address all of tlir
1.1 This guide covers soil sampling techniques, numbers
safety concerns, ìj any, associated with its use. It is the
of soil cores, root samples, and related procedures for soil
responsibility of the user of this standard to establish appro-
collection for nematode population studies.
priate safety and health practices and determine the applica-
la2 guide covers used to separate biìity of regulatory limitations prior to use, For more specific
nematodes from soil or roots, counting techniques, rating of
precautionary statements see 4.6.2.1, 5.3.1, Section 7, and
39.6.1.
I This guide is under the jurisdiction of ASTM Committee E-35 on Pesticides,
and is the direct responsibility of Subcommittee E35.16 on Nematode Control
Agents. 2. Terminology
Current edilion approved March 10, 1996. Published May 1996. Originally
2.1 ~~fi~i~i~~~,.
published as E 629 - 77. Last previous edition E 629 - 91.
2. * bioassay-the Of appropriate hosts to
2 The boldface numbers in parentheses refer to the list of references appended
to this guide.
determine relative population levels (has been used primarily
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