First Report of Rust Disease Caused by Puccinia sparganioides on Spartina alterniflora in Louisiana

Spartina alterniflora Loisel. (smooth cordgrass) is the dominant plant species of intertidal salt marshes in the Atlantic and Gulf Coast regions of the United States. It is a perennial deciduous grass that can reduce and reverse coastal erosion by buffering wave energy and storm surges and by accumulating suspended solids from intertidal waters. Therefore, smooth cordgrass is utilized extensively in coastal restoration projects in Louisiana. In July 2009, smooth cordgrass leaf samples with signs and symptoms of a rust disease were collected from plant material grown at the Aquaculture Research Station near Baton Rouge, LA. Numerous hypophyllous, narrow, linear lesions were observed in which the uredinia were pale orange, erumpent, and arranged seriately. Urediniospores were yellowish to orange, obovoid to oblong, echinulate with a thickened apical wall and obscure germ pores, and measured 27.5 to 44.9 (–48.3) × 17.3 to 27.6 (–31.05) μm. Telia and teliospores were not observed. The pathogen was identified as Puccinia sparganioides Ellis & Tracy based on the DNA sequence of nuclear ribosomal large subunit (28S) and internal transcribed spacer region 2 (ITS-2) amplified with rust-specific primers (1). The sequence (deposited in GenBank as No. GU327649) was found to share 99.8% identity (1,077/1,079 bp) with sequence No. GU058027 of P. sparganioides from S. patens (Aiton) Muhl. and did not match any other species of Puccinia in GenBank. P. sparganioides has previously been reported on S. alterniflora in Connecticut, Delaware, Florida, Maine, Massachusetts, Mississippi, North Carolina, New Hampshire, Rhode Island, Vermont, and Virginia (2). To the best of our knowledge, this is the first report of P. sparganioides on S. alterniflora from Louisiana. Efforts to screen for rust-resistant lines for use in coastal restoration projects are underway to prevent land loss that could occur due to smooth cordgrass stress from infection. Voucher material (LSU00121657) has been deposited in the Bernard Lowy Mycological Herbarium (LSUM). References: (1) M. C. Aime. Mycoscience 47:112, 2006. (2) D. F. Farr and A. Y. Rossman. Fungal Databases. Systematic Mycology and Microbiology Laboratory, Online publication. ARS, USDA, October, 2009.

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First Report of Uromyces plumbarius, Rust of Gaura, in Louisiana and a new host, Guara lindheimeri

Plant Disease ◽

10.1094/pdis-12-11-1020 ◽

2012 ◽

Vol 96 (4) ◽

pp. 590-590 ◽

Cited By ~ 1

Author(s):

R. Kaur ◽

A. R. McTaggart ◽

D. M. Ferrin ◽

M. C. Aime

Keyword(s):

Large Subunit ◽

Signs And Symptoms ◽

First Record ◽

The United States ◽

Home Garden ◽

Rust Disease ◽

High Sequence Identity ◽

New Host ◽

First Report ◽

Query Coverage

Gaura lindheimeri Engelm. & A. Gray (Onagraceae) is an ornamental shrub that is native to southern Louisiana and Texas. Its texture and form make it a popular perennial border plant. In April 2010 and 2011, three collections of Guara leaf samples with signs and symptoms of a rust disease were made from a home garden in Baton Rouge, LA. Infected leaves showed chlorotic lesions on the adaxial surface and were associated with scattered, hypophyllous uredinia. Urediniospores were globose to obovoid, echinulate, had two equatorial germ pores, and measured 16 to 21 × 18 to 25 μm with a wall 2 μm thick. Telia and teliospores were not observed on any of the collected samples. The pathogen was identified as Uromyces plumbarius Peck on the basis of the uredinial characters compared with four U.S. National Fungus (BPI 1103868, 0013551, 0013554, and 0013557) collections of U. plumbarius. The three collections from Louisiana have been deposited in the Bernard Lowy Mycological Herbarium. DNA was extracted from all three specimens and the nuclear ribosomal large subunit (28S) was amplified according to the protocol outlined by Aime (1). The three Louisiana collections had identical large subunit sequences (GenBank Accession Nos. JQ312670, JQ312671, and JQ312672). No sequences of U. plumbarius were available for comparison in GenBank; a BLAST search was 99% similar over 100% query coverage to Puccinia dioicae Magnus (Accession No. GU058019) and P. silvatica J. Schröt. (Accession No. AY222048). The uredinial/telial hosts of P. dioicae and P. silvatica are in the Cyperaceae, whereas U. plumbarius is an autoecious rust on Onagraceae. It is interesting to note that the aecial stage of P. dioicae occurs on Onagraceae and that it has a high sequence identity to U. plumbarius, supporting the hypothesis that these are correlated species (2). U. plumbarius has been recorded on several species of Gaura within the United States. To our knowledge, this is the first record of U. plumbarius in Louisiana and the first report of U. plumbarius on G. lindheimeri. References: (1) M. C. Aime. Mycoscience 47:112, 2006. (2) C. R. Orton. Mycologia 4:194, 1912.

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First Report of Monosporascus cannonballus on Melon in Mexico

Plant Disease ◽

10.1094/pdis-02-12-0181-pdn ◽

2012 ◽

Vol 96 (7) ◽

pp. 1068-1068 ◽

Cited By ~ 1

Author(s):

Y. I. Chew-Madinaveitia ◽

A. Gaytán-Mascorro ◽

T. Herrera-Pérez

Keyword(s):

Citrullus Lanatus ◽

The United States ◽

Internal Transcribed Spacer Region ◽

Oat Hulls ◽

Monosporascus Cannonballus ◽

First Report ◽

The North ◽

Root Necrosis ◽

Vine Decline ◽

Melon Seeds

In 2009, 2010, and 2011, melon plants (Cucumis melo L.) exhibited vine decline in commercial fields in the Municipality of Viesca, State of Coahuila, in the north-central region of Mexico known as La Comarca Lagunera. Symptoms included wilting, leaf yellowing, and vine collapse prior to harvest. Diseased plants showed necrotic root lesions and loss of secondary and tertiary roots. Numerous perithecia containing asci and ascospores typical of Monosporascus cannonballus Pollack & Uecker (3) were found in the root system. M. cannonballus is a typical fungus of hot semiarid climates such as La Comarca Lagunera in which daytime temperatures above 40°C are frequent during the melon growing season. Small root pieces were disinfected with 1.5% sodium hypochlorite for 1 min and plated onto potato dextrose agar (PDA) medium with 0.5 g l–1 streptomycin sulfate and incubated for 7 days at 25°C under dark conditions. The mycelium of the fungus colony was initially white, turning gray about 3 weeks later and yielding black perithecia with one ascospore per asci. The internal transcribed spacer region of ribosomal DNA of isolate 4 was sequenced and submitted to GenBank with Accession No. JQ51935. Pathogenicity of this isolate was confirmed on melon plants (cv. Cruiser) in the greenhouse at 25 to 32°C. Fungus inoculum was produced in a sand-oat hull medium (0.5 l of sand, 45 g of oat hulls, and 100 ml of distilled water), and incubated at 25°C for 50 days (1). Melon seeds were sown in sterile sand in 20-cm diameter and 12-cm depth polyurethane containers, and the inoculum was added to produce a concentration of 20 CFU g–1. Sowing was done in five inoculated containers and thinned to two plants per container, each container representing a replication. Plants were also grown in five noninoculated containers that were used as controls. After 50 days under greenhouse conditions, plants were evaluated for disease symptoms. Melon plants inoculated with M. cannonballus exhibited root necrosis as opposed to healthy roots observed in noninoculated plants. M. cannonballus was reisolated from symptomatic plants, confirming Koch's postulates. M. cannonballus causes root rot and vine decline on melon and has been reported in Brazil, Guatemala, Honduras, India, Iran, Israel, Italy, Japan, Libya, the Netherlands (plants from Russia), Pakistan, Saudi Arabia, Spain, Taiwan, Tunisia, and the United States. M. cannonballus was reported in 1996 in southeastern Mexico in the State of Colima, where watermelon (Citrullus lanatus (Thunb.) Matsum.& Nakai) showed wilting and plant collapse prior to harvest (2). However, to our knowledge, this is the first report of M. cannonballus on melon in Mexico. This is relevant because La Comarca Lagunera region is one of the major melon producing areas in Mexico and M. cannonballus is a pathogen that may cause yield losses of up to 100%. References: (1) B. D. Bruton et al. Plant Dis. 84:907, 2000. (2) R. D. Martyn et al. Plant Dis. 80:1430, 1996. (3) F. G. Pollack and F. A. Uecker. Mycologia 66:346, 1974.

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First Report of Phomopsis citri Associated with Dieback of Citrus lemon in India

Plant Disease ◽

10.1094/pdis-04-14-0388-pdn ◽

2014 ◽

Vol 98 (9) ◽

pp. 1281-1281 ◽

Cited By ~ 2

Author(s):

S. Mahadevakumar ◽

Vandana Yadav ◽

G. S. Tejaswini ◽

S. N. Sandeep ◽

G. R. Janardhana

Keyword(s):

Fungal Pathogen ◽

The United States ◽

Apical Region ◽

Post Inoculation ◽

Pathogenicity Test ◽

Conidial Suspension ◽

Internal Transcribed Spacer Region ◽

Productivity Level ◽

First Report ◽

Dieback Disease

Lemon (Citrus lemon (L.) Burm. f.) is an important fruit crop cultivated worldwide, and is grown practically in every state in India (3). During a survey conducted in 2013, a few small trees in a lemon orchard near Mysore city (Karnataka) (12°19.629′ N, 76°31.892′ E) were found affected by dieback disease. Approximately 10 to 20% of trees were affected as young shoots and branches showed progressive death from the apical region downward. Different samples were collected and diagnosed via morphological methods. The fungus was consistently isolated from the infected branches when they were surface sanitized with 1.5% NaOCl and plated on potato dextrose agar (PDA). Plates were incubated at 26 ± 2°C for 7 days at 12/12 h alternating light and dark period. Fungal colonies were whitish with pale brown stripes having an uneven margin and pycnidia were fully embedded in the culture plate. No sexual state was observed. Pycnidia were globose, dark, 158 to 320 μm in diameter, and scattered throughout the mycelial growth. Both alpha and beta conidia were present within pycnidia. Alpha conidia were single celled (5.3 to 8.7 × 2.28 to 3.96 μm) (n = 50), bigittulate, hyaline, with one end blunt and other truncated. Beta conidia (24.8 to 29.49 × 0.9 to 1.4 μm) (n = 50) were single celled, filiform, with one end rounded and the other acute and curved. Based on the morphological and cultural features, the fungal pathogen was identified as Phomopsis citri H.S. Fawc. Pathogenicity test was conducted on nine healthy 2-year-old lemon plants via foliar application of a conidial suspension (3 × 106); plants were covered with polythene bags for 6 days and maintained in the greenhouse. Sterile distilled water inoculated plants (in triplicate) served as controls and were symptomless. Development of dieback symptoms was observed after 25 days post inoculation and the fungal pathogen was re-isolated from the inoculated lemon trees. The internal transcribed spacer region (ITS) of the isolated fungal genomic DNA was amplified using universal-primer pair ITS1/ITS4 and sequenced to confirm the species-level diagnosis (4). The sequence data of the 558-bp amplicon was deposited in GenBank (Accession No. KJ477016.1) and nBLAST search showed 99% homology with Diaporthe citri (teleomorph) strain 199.39 (KC343051.1). P. citri is known for its association with melanose disease of citrus in India, the United States, and abroad. P. citri also causes stem end rot of citrus, which leads to yield loss and reduction in fruit quality (1,2). Dieback disease is of serious concern for lemon growers as it affects the overall productivity level of the tree. To the best of our knowledge, this is the first report of P. citri causing dieback of lemon in India. References: (1) I. H. Fischer et al. Sci. Agric. (Piracicaba). 66:210, 2009. (2) S. N. Mondal et al. Plant Dis. 91:387, 2007. (3) S. P. Raychaudhuri. Proc. Int. Soc. Citriculture 1:461, 1981. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990.

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Dieback of Salt-water Cordgrass (Spartina alterniflora Loisel.) in the Lower Cape Fear Estuary of North Carolina: An Experimental Approach to Re-establishment

Environmental Conservation ◽

10.1017/s0376892900006792 ◽

1980 ◽

Vol 7 (1) ◽

pp. 59-66 ◽

Cited By ~ 11

Author(s):

Rick A. Linthurst ◽

Ernest D. Seneca

Keyword(s):

North Carolina ◽

Spartina Alterniflora ◽

Salt Marshes ◽

Salt Water ◽

High Water ◽

The United States ◽

Salicornia Europaea ◽

Web Studies ◽

Mean High Water ◽

Cape Fear

Spartina alterniflora is the dominant endemic saltmarsh angiosperm along the East and Gulf coasts of the United States. Dieback of S. alterniflora became evident through aerial surveys of the Lower Cape Fear Estuary of North Carolina. The areas affected varied in size, the largest being greater than 40 ha in areal extent. As S. alterniflora productivity losses can subsequently affect the productivity of the estuarine detritus-based food-web, studies were initiated in 1975 to examine the dieback phenomenon, follow successional trends, and determine the recolonization potential of S. alterniflora in dieback-affected salt-marshes.Three S. alterniflora dieback sites in the Lower Cape Fear Estuary were selected for study. Two of the sites, both above mean high-water, were recolonized by Salicornia europaea, Distichlis spicata, Scirpus robustus, Spartina patens, and S. alterniflora. At a third site, found to be below mean high-water, all volunteer plants were of S. alterniflora. Final stabilization of all three sites was mainly by S. alterniflora, with the living standing-crop biomass ranging from 341 to 1,565 g/m2 in September of 1978.Experimental plots within each of the three dieback sites were sprigged with S. alterniflora plants from three sources: (i) sandy dredge-material, (ii) volunteer plants within affected sites, and (iii) unaffected sites near the dieback areas. The success of these sprigs was strongly site-dependent. It is suggested that the plants used for revegetation of dieback sites should be obtained from areas similar to the site that is being transplanted and/or plants which have large rhizome systems.

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First Report of Phytophthora nicotianae and P. citricola Associated with English Walnut Decline in Europe

Plant Disease ◽

10.1094/pdis.2003.87.3.315b ◽

2003 ◽

Vol 87 (3) ◽

pp. 315-315 ◽

Cited By ~ 1

Author(s):

A. Belisario ◽

M. Maccaroni ◽

A. M. Vettraino ◽

A. Vannini

Keyword(s):

Lateral Roots ◽

Juglans Regia ◽

The United States ◽

Phytophthora Nicotianae ◽

Malt Extract ◽

Veneto Region ◽

Internal Transcribed Spacer Region ◽

Campania Region ◽

First Report ◽

English Walnut

English (Persian) walnut (Juglans regia), among the most widely cultivated species of Juglans worldwide, is cultivated primarily for fruit production but also for timber. In the last 10 years, walnut decline causing leaf yellowing, sparse foliage, overall decline, and plant death has increased in Italian commercial orchards. In Italy, Phytophthora cactorum, P. cambivora, P. cinnamomi, and P. cryptogea are associated with this disease (1,4). Over the last 5 years, P. cinnamomi was the most widely isolated and destructive species (1). Recently, a different species of Phytophthora was isolated from diseased roots and soil from around lateral roots of 10 declining trees in two orchards in the Veneto Region of northern Italy. Another species of Phytophthora was isolated consistently from rotted roots of declining walnut trees in two orchards in the Campania Region of southern Italy. Phytophthora spp. were isolated directly from plant material or Rhododendron spp. leaf baiting on soil samples with PARBhy selective medium (10 mg of pimaricin, 250 mg of ampicillin [sodium salt], 10 mg of rifampicin, 50 mg of hymexazol, 15 mg of benomyl, 15 g of malt extract, 20 g of agar in 1,000 ml of H2O). Two species of Phytophthora were identified based on morphological and cultural characteristics (2). The species from trees in the Veneto Region was identified as P. nicotianae. All isolates produced papillate, spherical to obturbinate, occasionally caducous sporangia with short pedicels, terminal and intercalary chlamydospores, and were mating type A2. The species isolated from trees in the Campania Region was identified as P.citricola. Isolates were homothallic, produced semipapillate, persistent, obclavate to obpyriform sporangia, occasionally with two apices, and antheridia paragynous. Identifications were confirmed by comparing restriction fragment length polymorphism patterns of the internal transcribed spacer region of rDNA with those obtained from previously identified species of Phytophthora. Pathogenicity of two isolates each of P. citricola and P. nicotianae was tested on 2-year-old potted walnut seedlings. Inocula were prepared by inoculating sterilized millet seeds moistened with V8 broth with plugs of mycelium and incubated for 4 weeks at 20°C in the dark. Infested seeds were added to potting soil at a rate of 3% (wt/vol). One day later, pots were flooded for 48 h to promote sporulation. Ten noninoculated seedlings were used as the control. Symptoms were assessed 2 months after inoculation. Seedlings inoculated with P. nicotianae developed necrosis of feeder and lateral roots, but only limited infection of taproots. Seedlings inoculated with P. citricola developed necroses at the insertion points of lateral roots. All four isolates produced visible damage to lateral roots on inoculated plants. P. nicotianae and P. citricola were reisolated from respectively infected roots. Results from these inoculations confirmed P. nicotianae and P. citricola as root pathogens of English walnut. Both species were associated with walnut decline as reported in the United States (3). To our knowledge, this is the first report of P. nicotianae and P. citricola on J. regia in Europe. References: (1) A. Belisario et al. Petria 11:149. (2) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society, St. Paul, MN, 1996. (3) M. E. Matheron and S. M. Mircetich. Phytopathology 75:977, 1985. (4) A. M. Vettraino et al. Plant Dis. 86:328, 2002.

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First Report of Cytospora punicae Causing Wood Canker and Branch Dieback of Pomegranate (Punica granatum) in the United States

Plant Disease ◽

10.1094/pdis-11-13-1133-pdn ◽

2014 ◽

Vol 98 (6) ◽

pp. 853-853 ◽

Cited By ~ 5

Author(s):

F. Peduto Hand ◽

R. A. Choudhury ◽

W. D. Gubler

Keyword(s):

United States ◽

Elongation Factor ◽

Punica Granatum ◽

The United States ◽

Internal Transcribed Spacer Region ◽

Intermittent Light ◽

First Report ◽

Consensus Sequences ◽

Vascular Discoloration ◽

Branch Dieback

Pomegranates (Punica granatum L.) are an expanding industry in the United States with California growing approximately 32,000 acres with a crop value of over $155 million (1). During June and July of 2012, we observed severe limb and branch dieback in pomegranate orchards cv. Wonderful located in Contra Costa, Kings, and Kern counties of California. Disease symptoms included yellowing of leaves, branch and limb dieback, wood lesions, and canker formation. Dark brown Cytospora-like cultures were consistently isolated from active cankers on potato dextrose agar (PDA) amended with 100 mg l−1 tetracycline hydrochloride. Three isolates (UCCE1223, UCCE1233, and UCCE1234) representative of each orchard were sub-cultured onto PDA and incubated at 22°C under fluorescent intermittent light (12 h light, 12 h dark). Fungal colonies had whitish mycelia that turned olive green to dark brown with maturity and formed globose and dark brown pycnidia after 12 days. Conidia were hyaline, aseptate, allantoid, and (4) 4.5 to 5 (6) × (1) 1.5 (2) μm (n = 180). Pycnidia formed in culture measured (250) 350 to 475 (650) μm in diameter (n = 40). Identification of the isolates was confirmed by sequence comparison of the internal transcribed spacer region (ITS1-5.8S-ITS2) of the rDNA and part of the translation elongation factor 1-α gene (EF1-α) with sequences available in GenBank. Consensus sequences of both genes of all isolates showed 99% homology to the species Cytospora punicae Sacc. (2). All sequences were deposited in GenBank (Accession Nos. KJ621684 to 89). Pathogenicity of the isolates was determined by branch inoculation. In December 2012, 3-year-old branches of P. granatum cv. Wonderful were inoculated by placing 5-mm-diameter mycelium plugs from the growing margin of 14-day-old PDA cultures in fresh wounds made with a 5-mm-diameter cork-borer. Eight branches per isolate were inoculated on eight different trees. Eight control branches were inoculated with non-colonized PDA agar plugs. Inoculations were covered with Vaseline and wrapped with Parafilm to retain moisture. Branches were harvested in August 2013 and examined for canker development and the extent of vascular discoloration spreading downward and upward from the inoculation point. Isolations from the edge of discolored tissue were conducted to fulfill Koch's postulates. C. punicae was re-isolated from 100% of the inoculated branches. Total length of vascular discoloration averaged 30.2 mm in branches inoculated with the three C. punicae isolates and 9 mm in the control branches. No fungi were isolated from the slightly discolored tissue of the controls. To our knowledge, this is the first report of C. punicae as a fungal trunk pathogen of pomegranate trees in the United States. References: (1) California County Agricultural Commissioners' Data, 2010 Crop Year. USDA NASS California field office, retrieved from http://www.nass.usda.gov/Statistics_by_State/California/ Publications/AgComm/201010cactb00.pdf , 2011. (2) P. A. Saccardo. Sylloge Fungorum 3:256, 1884.

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Facilitation shifts paradigms and can amplify coastal restoration efforts

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1515297112 ◽

2015 ◽

Vol 112 (46) ◽

pp. 14295-14300 ◽

Cited By ~ 87

Author(s):

Brian R. Silliman ◽

Elizabeth Schrack ◽

Qiang He ◽

Rebecca Cope ◽

Amanda Santoni ◽

...

Keyword(s):

Salt Marshes ◽

Species Interactions ◽

Coastal Wetlands ◽

Current Practice ◽

The United States ◽

Positive Interactions ◽

Coastal Restoration ◽

Restoration Success ◽

Simple Change ◽

Bare Substrate

Restoration has been elevated as an important strategy to reverse the decline of coastal wetlands worldwide. Current practice in restoration science emphasizes minimizing competition between out-planted propagules to maximize planting success. This paradigm persists despite the fact that foundational theory in ecology demonstrates that positive species interactions are key to organism success under high physical stress, such as recolonization of bare substrate. As evidence of how entrenched this restoration paradigm is, our survey of 25 restoration organizations in 14 states in the United States revealed that >95% of these agencies assume minimizing negative interactions (i.e., competition) between outplants will maximize propagule growth. Restoration experiments in both Western and Eastern Atlantic salt marshes demonstrate, however, that a simple change in planting configuration (placing propagules next to, rather than at a distance from, each other) results in harnessing facilitation and increased yields by 107% on average. Thus, small adjustments in restoration design may catalyze untapped positive species interactions, resulting in significantly higher restoration success with no added cost. As positive interactions between organisms commonly occur in coastal ecosystems (especially in more physically stressful areas like uncolonized substrate) and conservation resources are limited, transformation of the coastal restoration paradigm to incorporate facilitation theory may enhance conservation efforts, shoreline defense, and provisioning of ecosystem services such as fisheries production.

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Positive interactions of the smooth cordgrass Spartina alterniflora on the mud snail Heleobia australis, in South Western Atlantic salt marshes

Journal of Experimental Marine Biology and Ecology ◽

10.1016/j.jembe.2007.09.009 ◽

2007 ◽

Vol 353 (2) ◽

pp. 180-190 ◽

Cited By ~ 15

Author(s):

Alejandro D. Canepuccia ◽

Mauricio Escapa ◽

Pedro Daleo ◽

Juan Alberti ◽

Florencia Botto ◽

...

Keyword(s):

Spartina Alterniflora ◽

Salt Marshes ◽

Positive Interactions ◽

Smooth Cordgrass ◽

Western Atlantic ◽

Mud Snail

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First Report of Pratylenchus neglectus on Winter Wheat in China

Plant Disease ◽

10.1094/pdis-04-12-0332-pdn ◽

2013 ◽

Vol 97 (1) ◽

pp. 151-151 ◽

Cited By ~ 2

Author(s):

H. Y. Wu ◽

Z. Z. Jia ◽

J. Liu ◽

J. Luo ◽

D. L. Peng

Keyword(s):

Winter Wheat ◽

Dna Sequencing ◽

The United States ◽

Vector System ◽

Internal Transcribed Spacer Region ◽

Wheat Roots ◽

Pratylenchus Neglectus ◽

First Report ◽

Wheat Production ◽

Lesion Nematode

Root-lesion nematodes are major pathogens of wheat and have been reported in the United States, Mexico, India, Australia, Egypt, Canary Islands, South Africa, Iran, Japan, the Netherlands, Belgium, Italy, Germany, and Yugoslavia (1). They can also cause injury in a large number of crops, including grasses, cereal grains, and vegetables. In 2009 and 2010, a survey was conducted for nematodes in winter wheat fields near Taian city, Shandong, northern China. Root tissues were stained via the acid fuchsin tissue stain technique, and nematode numbers were recorded under a stereo microscope. Sixty-eight root samples were collected during the winter wheat growing season, and root lesion nematode was found in all samples. The highest average lesion nematode populations in fresh roots were 154.3 nematodes/g in 2009 and 236.7 nematodes/g in 2010. Nematodes were collected from infested wheat roots by a modified Baermann funnel method. Dimensions of the nematodes were: length, 0.42 to 0.54 mm; a, 18.8 to 24.2; b, 4.4 to 5.7; c, 19.8 to 25.4; V, 80.4 to 84.8; and spear, 17.1 to 18.9 μm. DNA was extracted from individual nematodes using liquid nitrogen. Amplification of rDNA-internal transcribed spacer region using the forward primers 5′-CGTAACAAGGTAGCTGTAG-3′ and the reverse primer 5′-TTTCACTCGCCGTTACTAAGG-3′ yielded a PCR fragment of approximately 900 bp. PCR products were purified using Universal Plant DNA Purification Kit (Tiangen, China) and ligated to the pMD18-T vector system (TaKaRa Bio, Japan) and transformed to E. coli strain DH5α. Plasmid DNA carrying the insert was extracted and used as the template for DNA sequencing. DNA sequencing was carried out in an ABI 3730, compared and aligned using MEGA 5.0. Sequences showed 96% sequence identity with those of Pratylenchus neglectus (GenBank Accession No. FR692291.1). The sequence was submitted to the GenBank database (JX228136). To our knowledge, this is the first report of P. neglectus infesting winter wheat in China. P. neglectus has been reported as causing economically significant damage to wheat production of up to 70% yield loss in the Pacific Northwest. Damage from lesion nematode may therefore be potentially significant to wheat production in Shandong Province, and further information should be obtained on its prevalence. References: (1) P. A. A. Loof. The family Pratylenchidae Thorne, 1949. W. R. Nickle, ed., Manual of Agricultural Nematol. Marcel Dekker, Inc. New York, 1991. (2) R. W. Smiley et al. J. Nematol. 37:45, 2005.

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