{"id":2029,"date":"2016-06-02T07:00:06","date_gmt":"2016-06-02T14:00:06","guid":{"rendered":"http:\/\/blogs.cdfa.ca.gov\/Section3162\/?p=2029"},"modified":"2024-05-06T13:29:59","modified_gmt":"2024-05-06T20:29:59","slug":"helicotylenchus-spp-steiner-1945","status":"publish","type":"post","link":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?p=2029","title":{"rendered":"Helicotylenchus spp.  Steiner, 1945"},"content":{"rendered":"<h5 style=\"text-align: center;\"><a href=\"http:\/\/blogs.cdfa.ca.gov\/Section3162\/?attachment_id=2078\" rel=\"attachment wp-att-2078\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" data-attachment-id=\"2078\" data-permalink=\"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?attachment_id=2078\" data-orig-file=\"https:\/\/i0.wp.com\/blogs.cdfa.ca.gov\/Section3162\/wp-content\/uploads\/2016\/06\/5440548-helicotylenchus_Jonathan-D-Eisenback_VirginiaPolytechnicInstitute-and-StateUniv_Bugwood.org_1.jpg?fit=768%2C618&amp;ssl=1\" data-orig-size=\"768,618\" data-comments-opened=\"0\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"helicotylenchus spp.\" data-image-description=\"&lt;p&gt;Image Number: 5440548&lt;br \/&gt;\nspiral nematode (Helicotylenchus spp.) Steiner, 1945&lt;\/p&gt;\n&lt;p&gt;Photographer: Jonathan D. Eisenback, &lt;a href=&quot;http:\/\/www.forestryimages.org\/browse\/detail.cfm?imgnum=5440548&quot; target=&quot;_blank&quot; rel=&quot;noopener noreferrer&quot;&gt;bugwood.org&lt;\/a&gt;&lt;br \/&gt;\nOrganization: Virginia Polytechnic Institute and State University&lt;br \/&gt;\nDescriptor: Adult(s)&lt;br \/&gt;\nDescription: light micrograph of spiral nematode, Helicotylenchus sp.&lt;br \/&gt;\nImage type:Laboratory&lt;\/p&gt;\n\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/blogs.cdfa.ca.gov\/Section3162\/wp-content\/uploads\/2016\/06\/5440548-helicotylenchus_Jonathan-D-Eisenback_VirginiaPolytechnicInstitute-and-StateUniv_Bugwood.org_1.jpg?fit=474%2C381&amp;ssl=1\" class=\"aligncenter size-full wp-image-2078\" src=\"https:\/\/i0.wp.com\/blogs.cdfa.ca.gov\/Section3162\/wp-content\/uploads\/2016\/06\/5440548-helicotylenchus_Jonathan-D-Eisenback_VirginiaPolytechnicInstitute-and-StateUniv_Bugwood.org_1.jpg?resize=474%2C381\" alt=\"helicotylenchus spp.\" width=\"474\" height=\"381\" srcset=\"https:\/\/i0.wp.com\/blogs.cdfa.ca.gov\/Section3162\/wp-content\/uploads\/2016\/06\/5440548-helicotylenchus_Jonathan-D-Eisenback_VirginiaPolytechnicInstitute-and-StateUniv_Bugwood.org_1.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/blogs.cdfa.ca.gov\/Section3162\/wp-content\/uploads\/2016\/06\/5440548-helicotylenchus_Jonathan-D-Eisenback_VirginiaPolytechnicInstitute-and-StateUniv_Bugwood.org_1.jpg?resize=300%2C241&amp;ssl=1 300w\" sizes=\"auto, (max-width: 474px) 100vw, 474px\" \/><\/a><\/h5>\n<h5 style=\"text-align: center;\">California Pest Rating for<\/h5>\n<h5 style=\"text-align: center;\"><strong><em>Helicotylenchus <\/em><\/strong><strong>spp.\u00a0 Steiner, 1945 <\/strong><\/h5>\n<h5 style=\"text-align: center;\"><strong><span style=\"color: #ff0000;\">\u00a0<\/span>Pest Rating: C\u00a0<\/strong><\/h5>\n<p>&nbsp;<\/p>\n<hr \/>\n<h5 style=\"text-align: center;\"><strong>PEST RATING PROFILE<\/strong><\/h5>\n<h5><strong>Initiating Event: <\/strong><\/h5>\n<p>During the 1950-60s, several species of plant parasitic nematodes were given a \u2018D\u2019 rating as they were regarded as parasites, predators or organisms of little or no economic importance that did not require State enforced regulatory action.\u00a0 However, these nematode species were inaccurately assigned a D rating as most, if not all, are plant parasitic and therefore, capable of damaging plant production and causing significant economic losses especially at the county and local residential\/grower level.\u00a0 Furthermore, the detection of plant parasitic nematodes in nursery stock may be an indication of contamination in violation of the State\u2019s standard of pest cleanliness required for nurseries. <em>Helicotylenchus <\/em>spp<em>.<\/em> were originally rated D.\u00a0 The risk of infestation and permanent rating of this genus group are re-assessed here.<\/p>\n<h5><strong>History &amp; Status:<\/strong><\/h5>\n<p><strong><u>Background<\/u><\/strong>:\u00a0 Generally, pest risk assessments and assignment of pest ratings are conducted <em>per<\/em> individual pest species and not <em>per<\/em> genus group primarily due to differing pest biologies, geographical distributions, host ranges, damage potentials, and risk mitigating requirements. However, an exception to this rule is made here for the genus <em>Helicotylenchus<\/em> largely because of historical practice.\u00a0 Over the past several decades, the genus, <em>Helicotylenchus<\/em>, was seldom differentiated to species level by CDFA Nematologists mainly due to i) the common occurrence and wide distribution of member species within California, ii) no state enforced regulatory action required subsequent to their detection, and iii) greater demands of time involved in diagnosing high risk and other nematode species considered to be of greater economic importance than those belonging to <em>Helicotylenchus<\/em>.\u00a0 Alternately, certain species of the genus\u00a0 that are capable of invading plant roots (e.g., <em>H. multicinctus <\/em>B-rated) may be assessed and rated individually as they can be more economically damaging to crop production and trade markets than non-root invading species.<\/p>\n<p>Members of the genus, <em>Helicotylenchus<\/em>, are commonly known as \u2018spiral nematodes\u2019 since they assume a spiral form when relaxed with gentle heat.\u00a0 Species reproduce mainly by parthenogenesis producing eggs, three juvenile stages, and adults.\u00a0 These nematodes usually inhabit the soil-root region of plants and feed as obligate ectoparasites with their stylet (sword-like hollow tooth) inserted into the root. All motile juvenile and adult stages of <em>Helicotylenchus<\/em> feed. All species are parasitic on roots and other underground parts of plants (Siddiqi, 1972).<\/p>\n<p><strong><em>Hosts<\/em><\/strong>: <em>Helicotylenchus<\/em> spp. can attack a wide range of plants including agricultural crops, fruit trees, ornamentals, nursery stock, forest trees and shrubs, desert shrubs, grasses, and weeds. Species have been associated with different plants in soil around the root zone, however, the host status of associated plants is not always known.<\/p>\n<p><em><strong>Symptoms<\/strong>:\u00a0 <\/em>Feeding of <em>Helicotylenchus<\/em> spp. results in production of small discolored lesions in the root cortex and other underground parts.\u00a0 Local lesions in the cortex result in death of cells on which the nematodes feed.\u00a0 Feeding of high population levels of <em>Helicotylenchus<\/em> can severely damage roots by causing them to become slightly swollen, spongy, and discolored.\u00a0 Eventually the cortex of such roots is sloughed off (Maggenti, 1981; Mai <em>et al.,<\/em> 1960). Above ground symptoms may express yellowing of foliage, mild stunting, wilt and defoliation \u2013 depending on the population level of spiral nematodes present.<\/p>\n<p><em><strong>Damage Potential<\/strong>: \u00a0<\/em>Plant damage caused by high populations of spiral nematodes may be more significant in small-area plant productions and\/or containerized crops in nursery, residential and local situations than in large acreages and environments such as, pastures, parks, and cultivated fields.\u00a0 Crop damage under field conditions is difficult to assess as <em>Helicotylenchus<\/em> spp. are often mixed with other genera and\/or two or more spiral nematode species occurring together (Norton, 1984).\u00a0 <em>Helicotylenchus<\/em> spp. are considered mild plant pathogens.\u00a0 Crop losses under field conditions are not reported, however, under experimental conditions, reductions in root and total plant weight have been observed in cereals and grasses (Griffin, 1984).<\/p>\n<p><strong><em>Spread<\/em><\/strong>: \u00a0The main mode of long and short distance spread is through artificial means: movement of nematode-contaminated soil, run-off and irrigation water, cultivation tools, equipment and any human activity that can move soils from infested to non-infested sites.<\/p>\n<p><strong><u>Worldwide Distribution<\/u><\/strong>: <em>Helicotylenchus<\/em> spp. are distributed worldwide.<\/p>\n<p><strong><u>Official Control<\/u><\/strong>:\u00a0 Currently, <em>Helicotylenchus<\/em> spp. are D rated pests in California (see \u2018Initiating Event\u2019).\u00a0 <em>Helicotylenchus<\/em> spp. are on the \u2018Harmful Organism Lists\u201d for Australia, French Polynesia, Guatemala, Honduras, and Mexico (USDA-PCIT, 2016).<\/p>\n<p><strong><u>California Distribution<\/u><\/strong>:\u00a0 <em>Helicotylenchus<\/em> spp. are distributed throughout California.<\/p>\n<p><strong><u>California Interceptions<\/u><\/strong>: For the past several decades, <em>Helicotylenchus<\/em> spp. have been detected in several imported plant and soil shipments intercepted in California<\/p>\n<p>The risk <em>Helicotylenchus<\/em> spp. would pose to California is evaluated below.<\/p>\n<h5><strong>Consequences of Introduction: <\/strong><\/h5>\n<p><strong>1)\u00a0<span style=\"text-decoration: underline;\">Climate\/Host Interaction<\/span><\/strong>: Evaluate if the pest would have suitable hosts and climate to establish in California. Score:<\/p>\n<p style=\"padding-left: 30px;\">&#8211; Low (1) Not likely to establish in California; or likely to establish in very limited areas.<\/p>\n<p style=\"padding-left: 30px;\">&#8211; Medium (2) may be able to establish in a larger but limited part of California.<\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #008000;\">&#8211; <strong>High (3)<\/strong> likely to establish a widespread distribution in California.<\/span><\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #008000;\"><strong><em>Risk is High (3) <\/em><\/strong><\/span><em>\u2013 <\/em>Helicotylenchus spp. <em>are able to establish throughout the State. <\/em><\/p>\n<p><strong>2) <span style=\"text-decoration: underline;\">Known Pest Host Range<\/span><\/strong>: Evaluate the host range of the pest. Score:<\/p>\n<p style=\"padding-left: 30px;\">&#8211; Low (1) has a very limited host range.<\/p>\n<p style=\"padding-left: 30px;\">&#8211; Medium (2) has a moderate host range.<\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #008000;\">&#8211; <strong>High (3)<\/strong> has a wide host range.<\/span><\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #008000;\"><strong><em>Risk is High (3) <\/em><\/strong><\/span>\u2013 Helicotylenchus spp. <em>are known to be associated with several diverse plant species, however, the host status of associated plants is not always known.<\/em><\/p>\n<p><strong>3)\u00a0<span style=\"text-decoration: underline;\">Pest Dispersal Potential<\/span><\/strong>: Evaluate the natural and artificial dispersal potential of the pest. Score:<\/p>\n<p style=\"padding-left: 30px;\">&#8211; Low (1) does not have high reproductive or dispersal potential.<\/p>\n<p style=\"padding-left: 30px;\">&#8211; Medium (2) has either high reproductive or dispersal potential.<\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #008000;\">&#8211; <strong>High (3)<\/strong> has both high reproduction and dispersal potential.<\/span><\/p>\n<p style=\"padding-left: 30px;\"><strong><em><span style=\"color: #008000;\">Risk is High (3)<\/span> <\/em><\/strong><em>\u2013 The main mode of long and short distance spread is through artificial means: movement of contaminated soil, run-off and irrigation water, cultivation tools, equipment and any human activity that can move soils from infested to non-infested sites.\u00a0 Increase in reproduction rates depends on the plant species parasitized.<\/em><\/p>\n<p><strong>4) <span style=\"text-decoration: underline;\">Economic Impact<\/span><\/strong>: Evaluate the economic impact of the pest to California using the criteria below. Score:<\/p>\n<p style=\"padding-left: 30px;\">A. The pest could lower crop yield.<\/p>\n<p style=\"padding-left: 30px;\">B. The pest could lower crop value (includes increasing crop production costs).<\/p>\n<p style=\"padding-left: 30px;\">C. The pest could trigger the loss of markets (includes quarantines).<\/p>\n<p style=\"padding-left: 30px;\">D. The pest could negatively change normal cultural practices.<\/p>\n<p style=\"padding-left: 30px;\">E. The pest can vector, or is vectored, by another pestiferous organism.<\/p>\n<p style=\"padding-left: 30px;\">F. The organism is injurious or poisonous to agriculturally important animals.<\/p>\n<p style=\"padding-left: 30px;\">G. The organism can interfere with the delivery or supply of water for agricultural uses.<\/p>\n<p style=\"padding-left: 30px;\">&#8211; Low (1) causes 0 or 1 of these impacts.<\/p>\n<p style=\"padding-left: 30px;\">&#8211; Medium (2) causes 2 of these impacts.<\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #008000;\">&#8211; <strong>High (3)<\/strong> causes 3 or more of these impacts.<\/span><\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #008000;\"><strong><em>Risk is Low (1)<\/em><\/strong><\/span><em> \u2013 Generally, <\/em>Helicotylenchus<em> spp. are considered mild pathogens of plants.\u00a0 However, under high population levels in residential, nurseries and other small-area plantings, <\/em>Helicotylenchus<em> spp.<\/em> <em>infections could result in lowered crop yield.<\/em><\/p>\n<p><strong>5) Environmental Impact<\/strong>: Evaluate the environmental impact of the pest on California using the criteria below.<\/p>\n<p style=\"padding-left: 30px;\">A. The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.<\/p>\n<p style=\"padding-left: 30px;\">B. The pest could directly affect threatened or endangered species.<\/p>\n<p style=\"padding-left: 30px;\">C. The pest could impact threatened or endangered species by disrupting critical habitats.<\/p>\n<p style=\"padding-left: 30px;\">D. The pest could trigger additional official or private treatment programs.<\/p>\n<p style=\"padding-left: 30px;\">E. The pest significantly impacts cultural practices, home\/urban gardening or ornamental plantings.<\/p>\n<p>Score the pest for Environmental Impact. Score:<\/p>\n<p style=\"padding-left: 30px;\">&#8211; Low (1) causes none of the above to occur.<\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #008000;\">&#8211; <strong>Medium (2)<\/strong> causes one of the above to occur.<\/span><\/p>\n<p style=\"padding-left: 30px;\">&#8211; High (3) causes two or more of the above to occur.<\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #008000;\"><strong><em>Risk is Medium (2) <\/em><\/strong><\/span><em>\u2013 The impact of<\/em> Helicotylenchus spp. o<em>n natural environments is most likely not significant as the species is already widespread without causing apparent detriment to ecological balances and processes, however, heavy infestations of spiral nematodes could affect home\/urban gardening. <\/em><\/p>\n<h5><strong>Consequences of Introduction to California for <em>Helicotylenchus <\/em>spp<em>.:<\/em><\/strong><\/h5>\n<p>Add up the total score and include it here. (Score)<\/p>\n<p style=\"padding-left: 30px;\">-Low = 5-8 points<\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #008000;\">&#8211;<strong>Medium<\/strong> = 9-12 points<\/span><\/p>\n<p style=\"padding-left: 30px;\">-High = 13-15 points<\/p>\n<p>Total points obtained on evaluation of consequences of introduction of <em>Helicotylenchus <\/em>spp<em>.<\/em> to California = <strong><span style=\"color: #008000;\">(12)<\/span>.<\/strong><\/p>\n<p><strong>6) <span style=\"text-decoration: underline;\">Post Entry Distribution and Survey Information<\/span><\/strong>: Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included. (Score)<\/p>\n<p style=\"padding-left: 30px;\">-Not established (0) Pest never detected in California, or known only from incursions.<\/p>\n<p style=\"padding-left: 30px;\">-Low (-1) Pest has a localized distribution in California, or is established in one suitable climate\/host area (region).<\/p>\n<p style=\"padding-left: 30px;\">-Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate\/host areas.<\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #008000;\">&#8211;<strong>High (-3)<\/strong> Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate\/host areas.<\/span><\/p>\n<p style=\"padding-left: 30px;\"><strong><em><span style=\"color: #008000;\">Evaluation is High (-3)<\/span>.\u00a0 <\/em><\/strong>Helicotylenchus <em>spp<\/em>.<em> are widely spread in several contiguous and non-contiguous climate and host regions throughout the state.<\/em><\/p>\n<h5>Final Score:<\/h5>\n<p><strong>7) The final score is<\/strong> the consequences of introduction score minus the post entry distribution and survey information score: (Score)<\/p>\n<p><span style=\"color: #008000;\"><strong><em>Final Score: <\/em><\/strong><\/span><em>\u00a0Score of Consequences of Introduction \u2013 Score of Post Entry Distribution and Survey Information <span style=\"color: #008000;\"><strong>=<\/strong> <strong>9<\/strong><\/span><\/em><\/p>\n<h5><strong>Uncertainty:\u00a0 <\/strong><\/h5>\n<p><em>none.<\/em><\/p>\n<h5><strong>Conclusion and Rating Justification: <\/strong><\/h5>\n<p>Based on the evidence provided above <strong>the proposed rating for the spiral nematodes, <em>Helicotylenchus<\/em> spp., is C.<\/strong><\/p>\n<h5><strong>References:<\/strong><\/h5>\n<p><strong>G<\/strong>riffin, G. D.\u00a0 1984.\u00a0 Nematode parasites of alfalfa, cereals, and grasses.\u00a0 <em>In<\/em> Plant and Insect Nematodes, edited by W. R. Nickle.\u00a0 Marcel Dekker, Inc.\u00a0 New York and Basel.\u00a0 243-321 pp.<\/p>\n<p><strong>M<\/strong>ai, W. F., P. G. Mullin, H. H. Lyon, and K. Loeffler.\u00a0 1996.\u00a0 Plant parasitic nematodes \u2013 a pictorial key to genera.\u00a0 Fifth Edition.\u00a0 Comstock Publishing Associates a division of Cornell University Press, Ithaca and London.\u00a0 277 p.<\/p>\n<p><strong>M<\/strong>aggenti, A.\u00a0 1981.\u00a0 General nematology.\u00a0 Springer-Verlag New York Heidelberg Berlin.\u00a0 372 p.<\/p>\n<p><strong>N<\/strong>orton, D. C.\u00a0 1984.\u00a0 Nematode parasites of corn. <em>In<\/em> Plant and Insect Nematodes, edited by W. R. Nickle.\u00a0 Marcel Dekker, Inc.\u00a0 New York and Basel. 61-94 pp.<\/p>\n<p><strong>S<\/strong>iddiqi, M. R.\u00a0 1972.\u00a0 <em>Helicotylenchus dihystera<\/em>.\u00a0 Commonwealth Institute of Helminthology (C. I. H.) descriptions of plant-parasitic nematodes. Set 1, No. 9.<\/p>\n<p><strong>U<\/strong>SDA-PCIT.\u00a0 2016.\u00a0 United States Department of Agriculture, Phytosanitary Certificate Issuance &amp; Tracking System (PCIT). <a href=\"https:\/\/pcit.aphis.usda.gov\/PExD\/faces\/ViewPExD.jsp\" target=\"_blank\" rel=\"noopener\">https:\/\/pcit.aphis.usda.gov\/PExD\/faces\/ViewPExD.jsp<\/a> .<\/p>\n<hr \/>\n<h5>Responsible Party:<\/h5>\n<p>John J. Chitambar, Primary Plant Pathologist\/Nematologist, California Department of Food and Agriculture, 3294 Meadowview Road, Sacramento, CA 95832. Phone: 916-262-1110, plant.health[@]cdfa.ca.gov.<\/p>\n<hr \/>\n<h5>Comment Period: <span style=\"color: #ff0000;\">CLOSED<\/span><\/h5>\n<p>The 45-day comment period opened on Jun 2,\u00a02016 and\u00a0closed on Jul 17, 2016.<\/p>\n<hr \/>\n<h5>Comment Format:<\/h5>\n<p>\u2666 \u00a0Comments should refer to the appropriate California Pest Rating Proposal Form subsection(s)\u00a0being commented on, as shown below.<\/p>\n<p style=\"padding-left: 30px;\"><strong><span style=\"text-decoration: underline;\">Example Comment<\/span>:\u00a0<\/strong><\/p>\n<p style=\"padding-left: 30px;\">Consequences of Introduction: \u00a01. Climate\/Host Interaction:\u00a0[<em>Your comment that relates to \u201cClimate\/Host Interaction\u201d here.<\/em>]<\/p>\n<p>\u2666 \u00a0Posted comments will not be able to be viewed immediately.<\/p>\n<p>\u2666 \u00a0Comments may not be posted if they:<\/p>\n<p style=\"padding-left: 30px;\">Contain inappropriate language which is not germane to\u00a0the pest rating proposal;<\/p>\n<p style=\"padding-left: 30px;\">Contains defamatory, false, inaccurate, abusive, obscene, pornographic,\u00a0sexually oriented, threatening, racially offensive, discriminatory or illegal\u00a0material;<\/p>\n<p style=\"padding-left: 30px;\">Violates agency regulations prohibiting sexual harassment or other forms\u00a0of discrimination;<\/p>\n<p style=\"padding-left: 30px;\">Violates agency regulations prohibiting workplace violence, including threats.<\/p>\n<p>\u2666 \u00a0Comments may be edited prior to posting to ensure they are entirely germane.<\/p>\n<p>\u2666 \u00a0Posted comments shall be those which have been approved in content and posted to the\u00a0website to be viewed, not just submitted.<\/p>\n<hr \/>\n<h3 style=\"text-align: left;\"><strong>Pest Rating: C\u00a0<\/strong><\/h3>\n<hr \/>\n<p style=\"text-align: left;\"><em>Posted by ls\u00a0<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>California Pest Rating for Helicotylenchus spp.\u00a0 Steiner, 1945 \u00a0Pest Rating: C\u00a0 &nbsp; PEST RATING PROFILE Initiating Event: During the 1950-60s, several species of plant parasitic nematodes were given a \u2018D\u2019 rating as they were regarded as parasites, predators or organisms of little or no economic importance that did not require State enforced regulatory action.\u00a0 However, &hellip; <a href=\"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?p=2029\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Helicotylenchus spp.  Steiner, 1945<\/span> <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1117,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[27],"tags":[335,188],"class_list":["post-2029","post","type-post","status-publish","format-standard","hentry","category-nematodes","tag-helicotylenchus","tag-nematodes"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p5l8vQ-wJ","jetpack-related-posts":[{"id":382,"url":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?p=382","url_meta":{"origin":2029,"position":0},"title":"Helicotylenchus multicinctus (Cobb, 1893) Golden, 1956","author":"Admin","date":"March 16, 2015","format":false,"excerpt":"California Plant Pest Rating for Helicotylenchus multicinctus (Cobb, 1893) Golden, 1956 Pest\u00a0Rating:\u00a0B \u00a0 PEST RATING PROFILE Initiating Event: None. An evaluation of the risk involved with the possible introduction and spread of H. multicinctus in California is documented herein and a permanent rating is proposed for the species. History &\u2026","rel":"","context":"In &quot;Nematodes&quot;","block_context":{"text":"Nematodes","link":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?cat=27"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1955,"url":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?p=1955","url_meta":{"origin":2029,"position":1},"title":"Nematodes","author":"Admin","date":"May 13, 2016","format":false,"excerpt":"(Plant Parasitic Nematodes) Nematodes (also called \u2018roundworms\u2019) are relatively small, multicellular, worm-like animals. They are found in almost every environmental niche imaginable, living free in soil, marine and freshwater habitats while feeding on bacteria, fungi, and nematodes, or as parasites of humans, insects, fish, larger animals and plants. Plant parasitic\u2026","rel":"","context":"In &quot;Ratings&quot;","block_context":{"text":"Ratings","link":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?cat=333"},"img":{"alt_text":"Nematodes montage","src":"https:\/\/i0.wp.com\/blogs.cdfa.ca.gov\/Section3162\/wp-content\/uploads\/2016\/05\/nematodes-featured-image.jpg?fit=1038%2C588&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/blogs.cdfa.ca.gov\/Section3162\/wp-content\/uploads\/2016\/05\/nematodes-featured-image.jpg?fit=1038%2C588&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/blogs.cdfa.ca.gov\/Section3162\/wp-content\/uploads\/2016\/05\/nematodes-featured-image.jpg?fit=1038%2C588&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/blogs.cdfa.ca.gov\/Section3162\/wp-content\/uploads\/2016\/05\/nematodes-featured-image.jpg?fit=1038%2C588&ssl=1&resize=700%2C400 2x"},"classes":[]},{"id":9094,"url":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?p=9094","url_meta":{"origin":2029,"position":2},"title":"Hemicriconemoides spp. Chitwood &#038; Birchfield, 1957 Sheathoid nematodes","author":"Heather.Martin","date":"October 27, 2021","format":false,"excerpt":"California Pest Rating for Hemicriconemoides spp. Chitwood & Birchfield, 1957 Sheathoid nematodesPest Rating: C DOWNLOAD PEST RATING *NOTE You must be registered and logged in to post a comment. If you have registered and have not received the registration confirmation, please contact us at permits[@]cdfa.ca.gov. Posted by ta","rel":"","context":"In &quot;C-Rated&quot;","block_context":{"text":"C-Rated","link":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?cat=671"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":6389,"url":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?p=6389","url_meta":{"origin":2029,"position":3},"title":"Paratrichodorus spp. (Siddiqi 1974) and Trichodorus spp. (Cobb 1913)","author":"Heather.Martin","date":"September 4, 2019","format":false,"excerpt":"California Pest Rating for Paratrichodorus spp. (Siddiqi 1974) and Trichodorus spp. (Cobb 1913) Pest Rating: C DOWNLOAD PEST RATING Responsible Party: Heather J. Scheck, CDFA Primary Plant Pathologist\/Nematologist. 204 West Oak Ave, Lompoc, CA93463. 805-736-8050. plant.health[@]cdfa.ca.gov. *NOTE: You must be registered and logged in to post a comment. If you\u2026","rel":"","context":"In &quot;C-Rated&quot;","block_context":{"text":"C-Rated","link":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?cat=671"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":6404,"url":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?p=6404","url_meta":{"origin":2029,"position":4},"title":"Quinisulcius spp. Siddiqi 1971","author":"Heather.Martin","date":"September 4, 2019","format":false,"excerpt":"California Pest Rating for Quinisculcius spp. Siddiqi 1971 Pest Rating: C DOWNLOAD PEST RATING Responsible Party: Heather J. Scheck, CDFA Primary Plant Pathologist\/Nematologist. 204 West Oak Ave, Lompoc, CA93463. 805-736-8050. plant.health[@]cdfa.ca.gov. *NOTE: You must be registered and logged in to post a comment. If you have registered and have not\u2026","rel":"","context":"In &quot;Nematodes&quot;","block_context":{"text":"Nematodes","link":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?cat=27"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":6399,"url":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?p=6399","url_meta":{"origin":2029,"position":5},"title":"Merlinius spp. (Allen 1955) Siddiqi, 1970","author":"Heather.Martin","date":"September 4, 2019","format":false,"excerpt":"California Pest Rating for Merlinius spp. (Allen 1955) Siddiqi, 1970 Pest Rating: C DOWNLOAD PEST RATING Responsible Party: Heather J. Scheck, CDFA Primary Plant Pathologist\/Nematologist. 204 West Oak Ave, Lompoc, CA93463. 805-736-8050. plant.health[@]cdfa.ca.gov. *NOTE: You must be registered and logged in to post a comment. If you have registered and\u2026","rel":"","context":"In &quot;C-Rated&quot;","block_context":{"text":"C-Rated","link":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/?cat=671"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]}],"_links":{"self":[{"href":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/index.php?rest_route=\/wp\/v2\/posts\/2029","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/index.php?rest_route=\/wp\/v2\/users\/1117"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2029"}],"version-history":[{"count":9,"href":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/index.php?rest_route=\/wp\/v2\/posts\/2029\/revisions"}],"predecessor-version":[{"id":4655,"href":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/index.php?rest_route=\/wp\/v2\/posts\/2029\/revisions\/4655"}],"wp:attachment":[{"href":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2029"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2029"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.cdfa.ca.gov\/Section3162\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2029"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}