Genomics-First Evaluation of Heart Disease Associated With Titin-Truncating Variants

BACKGROUND

Truncating variants in the Titin gene (TTNtvs) are common in individuals with idiopathic dilated cardiomyopathy (DCM). However, a comprehensive genomics-first evaluation of the impact of TTNtvs in different clinical contexts, and the evaluation of modifiers such as genetic ancestry, has not been performed.

METHODS

We reviewed whole exome sequence data for >71 000 individuals (61 040 from the Geisinger MyCode Community Health Initiative (2007 to present) and 10 273 from the PennMedicine BioBank (2013 to present) to identify anyone with TTNtvs. We further selected individuals with TTNtvs in exons highly expressed in the heart (proportion spliced in [PSI] >0.9). Using linked electronic health records, we evaluated associations of TTNtvs with diagnoses and quantitative echocardiographic measures, including subanalyses for individuals with and without DCM diagnoses. We also reviewed data from the Jackson Heart Study to validate specific analyses for individuals of African ancestry.

RESULTS

Identified with a TTNtv in a highly expressed exon (hiPSI) were 1.2% individuals in PennMedicine BioBank and 0.6% at Geisinger. The presence of a hiPSI TTNtv was associated with increased odds of DCM in individuals of European ancestry (odds ratio [95% CI]: 18.7 [9.1-39.4] {PennMedicine BioBank} and 10.8 [7.0-16.0] {Geisinger}). hiPSI TTNtvs were not associated with DCM in individuals of African ancestry, despite a high DCM prevalence (odds ratio, 1.8 [0.2-13.7]; P=0.57). Among 244 individuals of European ancestry with DCM in PennMedicine BioBank, hiPSI TTNtv carriers had lower left ventricular ejection fraction (β=-12%, P=3×10^-7), and increased left ventricular diameter (β=0.65 cm, P=9×10^-3). In the Geisinger cohort, hiPSI TTNtv carriers without a cardiomyopathy diagnosis had more atrial fibrillation (odds ratio, 2.4 [1.6-3.6]) and heart failure (odds ratio, 3.8 [2.4-6.0]), and lower left ventricular ejection fraction (β=-3.4%, P=1×10^-7).

CONCLUSIONS

Individuals of European ancestry with hiPSI TTNtv have an abnormal cardiac phenotype characterized by lower left ventricular ejection fraction, irrespective of the clinical manifestation of cardiomyopathy. Associations with arrhythmias, including atrial fibrillation, were observed even when controlling for cardiomyopathy diagnosis. In contrast, no association between hiPSI TTNtvs and DCM was discerned among individuals of African ancestry. Given these findings, clinical identification of hiPSI TTNtv carriers may alter clinical management strategies.

Type specimens on deposit in the United States department of agriculture nematode collection, beltsville, Maryland

A list of the deposited type specimens with references, a detailed historical background, importance, and maintenance procedures are given for the type collection of the United States Department of Agriculture Nematode Collection (USDANC). The type specimen section is considered one of the largest and most valuable in existence. It contains 1,430 species mounted and preserved on 5,177 metal and glass slides and 404 vials. Also, a brief description of the other constituent divisions of the collection is given, which, including the type collection, consists of 34,000 permanent slides and vials and 19,500 species entries. The list of deposited types is a type specimen location reference only and should not be used for the status of type species. The generic and specific names are arranged in alphabetical order and are given as indicated by the author(s) or depositor(s) when the types were deposited in the type section of the USDANC. The complete title of the reference is not given for each species, only the author's date, and source and slide number(s). Also, included are authors of designated types other than those of the original type series, e.g. paralectotype, allolectotype, neotype.

Envelope sequence variability and serologic characterization of HIV type 1 group O isolates from equatorial guinea

Four sera from Equatorial Guinea (EG) suspected to contain antibody against HIV-1 group O-related viruses were identified on the basis of unusual and differential serologic reactivity in selected commercial assays and Western blot. Degenerate primers, designed from HIV-1 group O published sequences, were used to PCR amplify envelope (env) gene sequences from the suspect EG sera. A complete envelope gene sequence from each serum was determined from the overlapping env gene fragments. Analysis (PHYLIP package of programs) of Env amino acid sequences (translated from nucleotide sequences) indicated that the amino acid sequences obtained from EG sera clustered more closely with HIV Env sequences of group O compared to group M. The amino acid sequences at the octameric tip of the V3 loop were either RIGPLAWY (one isolate), RIGPMAWY (two isolates), or GLGPLAVY (one isolate). The V3 tip tetrameric sequence GPLA is represented only once in the 1995 HIV (Los Alamos) database, but was present in two of our group O-related EG samples. The gp41 immunodominant regions (IDR) protein sequences were identical for sequences from three of the sera, RLLALETLIQNQQLLNLWGCKGR(K)L(I)VCYTSVK(T)W, whereas sequence from the fourth serum contained three changes as noted in parentheses. IDR sequences derived from EG sera were unique compared to those reported for other HIV-1 group O isolate ANT70, VAU, or MVP5180. Antibody in each EG serum directed against the IDR could be detected using synthetic peptides comprising sequences from the ANT70 or MVP5180 IDRs, but were most reactive against the sequences derived from the samples themselves. Little or no serologic reactivity was detected when EG sera were reacted against peptides comprising the IDR of HIV-1 group M (subtype B consensus) or HIV-2 (consensus).

Molecular analyses of HIV-1 group O and HIV-2 variants from Africa

Genetic variation among HIV isolates creates challenges for their detection by serologic and genetic techniques. To characterize the sequence variation and its correlation to serologic diversity of HIV-1 Group O and HIV-2 isolates, samples were identified by differential reactivity in selected commercial and research assays. Analysis of sera from Equatorial Guinea (EG) led to identification of 4 HIV-1 Group O variants. Viral RNA, extracted from these samples was used to PCR amplify overlapping sequences of the entire envelope gene using multiple primer pairs. Sequence analysis indicated that the V3 loop nucleotide and protein sequences aligned more closely with HIVANT70 compared to other Group O sequences. The amino acid sequences at the octameric tip of the V3 loop were RIGPLAWY, RIGPMAWY, or GLGPLAVY. The tetrameric tip GPLA is represented only once in the published 1994 HIV database (Los Alamos) but was present in 2 of 4 of EG samples. The immuno-dominant region (IDR) sequences derived from EG sera were unique in that none of the sequences were completely homologous to other HIV-1 group O variants. Further, the HIV-1 group O sequence variation could be correlated with differential serologic reactivity using IDR peptides. Compared to HIV-1, the sequence information on HIV-2 isolates is relatively limited, though the HIV-2 isolates also show genetic variation similar to HIV-1. To further establish a correlation between the genetic diversity and serologic detection of HIV-2, plasma samples from Western Africa were evaluated. Eight samples were selected based on weak serologic reactivity to env proteins. PCR amplification and sequence analysis of the gag, env V3 loop, and env IDR regions indicated that the samples could be classified as subtypes A (4 samples), B (3 samples) and D (1 sample). Across the subtypes, there was conservation in the IDR region of the sequence WGCAFRQVCHT. This region is absolutely conserved among the majority of currently known HIV-2 and related SIV viruses (1994 HIV database). One subtype B sample had a unique sequence immediately adjacent to the IDR, however, this did not change the serologic detection using a HIV-2 IDR specific monoclonal antibody.

Rotations with Coastal Bermudagrass and Fallow for Management of Meloidogyne incognita and Soilborne Fungi on Vegetable Crops

The efficacy of fallow and coastal bermudagrass (Cynodon dactylon) as a rotation crop for control of root-knot nematode (Meloidogyne incognita race 1) and soilborne fungi in okra (Hibiscus esculentus cv. Emerald), squash (Cucurbita pepo cv. Dixie Hybrid), and sweet corn (Zea mays cv. Merit) was evaluated in a 3-year field trial. Numbers of M. incognita in the soil and root-gall indices were greater on okra and squash than sweet corn and declined over the years on vegetable crops following fallow and coastal bermudagrass sod. Fusarium oxysporum and Pythium spp. were isolated most frequently from soil and dying okra plants. Numbers of colony-forming units of soilborne fungi generally declined as the number of years in sod increased, but were not affected by coastal bermudagrass sod. Yields of okra following 2-year and 3-year sod and squash following 2-year sod were greater than those following fallow. Yield of sweet corn was not different following fallow and coastal bermudagrass sod.

Description of Tylenchorhynchus thermophilus n. sp. (Nematoda: Tylenchina) from Saltgrass in Death Valley, California

A stunt nematode, Tylenchorhynchus thermophilus n. sp., is described and illustrated from soil collected around roots of saltgrass (Distichlis spicata) in Death Valley, California. It is distinguished from the similar species, T. ewingi, T. mexicanus, and T. mashoodi, in having a longer female body, longer tail with more annules, and larger phasmids. Physical and chemical analysis of soil from saltgrass roots showed it to consist of 71% sand and possess high salinity (salt content of 0.51%) and a pH of 9.3.

Description and SEM Observations of Meloidogyne sasseri n. sp. (Nematoda: Meloidogynidae), Parasitizing Beachgrasses

Meloidogyne sasseri n. sp. is described and illustrated from American beachgrass (Ammophila breviliffulata) originally collected from Henlopen State Park and Fenwick Island near the Maryland state line in Delaware, United States (6). Its relationship to M. graminis, M. spartinae, and M. californiensis is discussed. Primary distinctive characters of the female perineal pattern were a high to rounded arch with shoulders, widely spaced lateral lines interrupting transverse striations, a sunken vulva and anus, and coarse broken striae around the anal area. Second-stage juvenile body length was 554 mum (470-550), stylet length 14 mum (13-14.5), tail length 93 mum (83-115), tapering to a finely rounded terminus. Male stylet length 20 mum (19-21.5), spicule length 33 mum (30-36). Scanning electron microscope observations provided additional details of perineal patterns and face views of the female, male, and J2 head. Wheat, rice, oat, Ammophila sp., Panicum sp., bermudagrass, zoysiagrass and St. Augustinegrass were tested as hosts. Distribution of the species was the coasts of Delaware and Maryland. The common name "beachgrass root-knot" is proposed for M. sasseri n. sp.

Chemigation for Control of Black Shank-Root-knot Complex and Weeds in Tobacco

Tank mixes of a fungicide (metalaxyl) and a nematicide (fenamiphos) with herbicides (isopropalin or pendimethalin) and an insecticide (chlorpyrifos) were applied by soil incorporation or irrigation to control the black shank-root knot complex and weeds on four tobacco cultivars. The disease complex was more severe on cultivars McNair 944, NC-2326, and K-326 than on Speight G-70. The disease complex was reduced (P </= 0.05) on all cultivars with the pesticide combinations containing metalaxyl + fenamiphos. On most cultivars, percentage disease, disease index, root-gall index, yield, and weed control did not differ (P </= 0.05) between the tank mixes containing isopropalin or pendimethalin or among methods of application. Generally, the most effective method of treatment application for control of the disease complex and weeds was preplant incorporated followed by postplant irrigation and preplant irrigation.

Nematode numbers and crop yield in a fenamiphos-treated sweet corn-sweet potato-vetch cropping system

Nematode population densities and yield of sweet corn and sweet potato as affected by the nematicide fenamiphos, in a sweet corn-sweet potato-vetch cropping system, were determined in a 5-year test (1981-85). Sweet potato was the best host of Meloidogyne incognita of these three crops. Fenamiphos 15G (6.7 kg a.i./ha) incorporated broadcast in the top 15 cm of the soil layer before planting of each crop increased (P </= 0.05) yields of sweet corn in 1981 and 1982 and sweet potato number 1 grade in 1982 and 1983. Yield of sweet corn and numbers of M. incognita second-stage juveniles (J2) in the soil each month were negatively correlated from planting (r = - 0.47) to harvest (r = -0.61) in 1982. Yield of number 1 sweet potato was inversely related to numbers of J2 in the soil in July-October 1982 and July-September 1983. Yield of cracked storage roots was positively related to the numbers of J2 in the soil on one or more sampling dates in all years except 1985. Some factor(s), such as microbial degradation, resistant M. incognita development, or environment, reduced the effect of fenamiphos.

Description of Pratylenchus gutierrezi n. sp. (Nematoda: Pratylenchidae) from Coffee in Costa Rica

A lesion nematode, Pratylenchus gutierrezi n. sp., collected from the roots of coffee in the Central Plateau of Costa Rica, is described and illustrated. Its relationships to Pratylenchus flakkensis, P. similis, and P. gibbicaudatus, the only other species of the genus having two head annules, males, or spermatheca with sperm, and an annulated tail terminus, is discussed. Other distinctive characters are its posterior vulva (mean of 80%); its prominently rounded stylet knobs, low head, and subcylindrical tail. SEM observations provide additional details of females and males, especially face views, which show for the first time sexual dimorphism.

Effects of Rapeseed and Vetch as Green Manure Crops and Fallow on Nematodes and Soil-borne Pathogens

In a rapeseed-squash cropping system, Meloidogyne incognita race 1 and M. javanica did not enter, feed, or reproduce in roots of seven rapeseed cultivars. Both nematode species reproduced at low levels on roots of the third crop of rapeseed. Reproduction of M. incognita and M. javanica was high on squash following rapeseed, hairy vetch, and fallow. The application of fenamiphos suppressed (P = 0.05) root-gall indices on squash following rapeseed, hairy vetch, and fallow; and on Dwarf Essex and Cascade rapeseed, but not Bridger and Humus rapeseed in 1987. The incorporation of 30-61 mt/ha green biomass of rapeseed into the soil 6 months after planting did not affect the population densities of Criconemella ornata, M. incognita, M. javanica, Pythium spp., Rhizoctonia solani AG-4; nor did it consistently increase yield of squash. Hairy vetch supported larger numbers of M. incognita and M. javanica than rapeseed cultivars or fallow. Meloidogyne incognita and M. javanica survived in fallow plots in the absence of a host from October to May each year at a level sufficient to warrant the use of a nematicide to manage nematodes on the following susceptible crop.

A key and diagnostic compendium to the species of the genus hoplolaimus daday, 1905 (nematoda: hoplolaimidae)

An identification key to 29 valid species of Hoplolaimus is given. A compendium of the most important diagnostic characters for use in identification of species is included as a practical alternative and supplement to the key. Diagnosis of Hoplolaimus is emended and lists of species of the genus, their synonymies, species inquirendae, nomina nuda, and species transferred to other genera are given. Hoplolaimus sheri, H. chambus, H. casparus, and H. capensis are recognized as valid species.

Nematodes associated with blackberry in arkansas

A survey of the nematodes in blackberry (Rubus sp.) rhizospheres was conducted in Arkansas from 1986 to 1989. The state was divided arbitrarily into four quadrants. A total of 134 soil samples was collected, and 150-cm 3 subsamples were assayed for nematodes. Twenty-one species of plant-parasitic nematodes in 11 genera were extracted from the samples. There were differences (P = 0.05) among quadrants of the state in percentage occurrence of the nematodes and in population densities in samples. Xiphinema americanum, Helicotylenchus spp. (H. paraplatyurus, H. platyurus, and H. pseudorobustus), and Pratylenchus spp. (P. vulnus and P. zeae) were found in all quadrants. Xiphinema americanum population density was near 1,000 per 150 cm(3) soil in soil samples from two locations. Other nematodes found in one or more quadrants were Criconemella spp. (C. axeste, C. curvata, C. denoudeni, C. ornata, C. sphaerocephala, and C. xenoplax), Paratrichodorus minor, Tylenchorhynchus claytoni, Hirschmanniella oryzae, Hoplolaimus magnistylus, Scutellonema bradys, and undescribed species of Criconema, Tylenchulus, Xiphinema, and Meloidogyne. Criconemella sphaerocephala and Helicotylenchus platyurus are reported from Arkansas for the first time. Helicotylenchus paraplatyurus is reported from the United States for the first time.

Evaluating cancer patients for rehabilitation potential

The Karnofsky performance scale is the most widely used method of quantifying cancer patients' ability to function. It has also been used to measure patients' function before and after treatment. Because identifying problems with function is the cornerstone of rehabilitating patients with cancer, we developed a table that relates the functional independence measure with the Karnofsky scale. This approach encourages oncologists to consider inpatient or outpatient rehabilitation services for a broader range of cancer patients. We assessed 70 cancer patients undergoing rehabilitation to identify similarities between the functional independence measure used at our facility and the Karnofsky scale. In activities we considered vital, only 14% of patients were independent with ambulation on admission and, at discharge, 80% were independent or supervised with ambulation. Toilet transfers and bowel and bladder continence improved by the time of discharge. Three months after they were discharged, 28 of the 37 patients had maintained their discharge function level or had improved. Of the original group, 19 had died.

Tylenchulus palustris Parasitizing Peach Trees in the of nited States

Most morphological characteristics of three populations of a Tylenchulus sp. from peach roots in Alabama, Arkansas, and Georgia did not differ from those of T. palustris paratypes. However, some mature females differed slightly from those of T. palustris paratypes from Florida. These mature females were more swollen in the posterior portion of their bodies, and they possessed digitate postvulval body sections with round rather than conoid termini. These morphological variants had a wide postvulval section core (PVSC), as do T. palustris paratypes; they did not differ from the paratypes in other characteristics. Second-stage juveniles and males were less morphologically variable and were not different from the paratypes. No males were found in populations from Alabama and Georgia. The Tylenchulus sp. from three peach sites was determined to be T. palustris. This is the first report of T. palustris on an economically important crop.

Plant nematodes occurring in arkansas

A total of 110 species of plant nematodes were found in various habitats in Arkansas. Thirty species from 19 genera are reported here for the first time. Included in the new reports are the known plant pathogens Criconemella onoense, Hirshmanniella oryzae, Longidorus elongatus, and Pratylenchus pratensis.

Further Details and SEM Observations on Meloidogyne marylandi (Nematoda: Meloidogynidae)

Specimens of Meloidogyne marylandi from Bermuda grass and a population from Zoysia grass were examined and compared morphologically by light and electron microscopy. The populations probably are conspecific and the differences noted in the Zoysia population, mainly those of second-stage juveniles (J2) with shorter tails, are considered normal variations rather than representing another form. Scanning electron microscope observations provided additional details of the perineal pattern and head of females and head and lateral fields of second-stage juveniles. Relationship of M. marylandi to closely related species is given. This species is currently known to occur only in Maryland, and populations previously reported from this state as M. graminis are now considered to be M. marylandi. Other reports of M. graminis in the United States now need to be reconfirmed by examination of voucher or recollected specimens.

A key and diagnostic compendium to the species of the genus pratylenchus filipjev, 1936 (lesion nematodes)

An identification key to 63 species of Pratylenchus is given. A compendium of the most diagnostic characters to be used directly in identification of species is included as a practical alternative and supplement to the key. P. tenuis, P. similis, P. impar, P. ranjani, and P. neocapitatus are recognized as valid species on the basis of study of type specimens. P. hyderabadensis Singh &Gill, 1986 is synonymized with P. dasi Fortuner, 1985. P. hexincisus Taylor &Jenkins, 1957 is confirmed as occasionally having 4 -6 lines in lateral field (instead of 6 only). Comments on the status of some species and a list of species of the genus are given.

Description of the Male of Ogma cobbi and Juveniles of Bakernema inaequale (Nematoda: Criconematidae)

Juveniles ofBakernema inaequale and the male of Ogma cobbi are described and illustrated for the first time. Juveniles of Bakernema inaequale lack the cuticular spines characteristic of the adults. The annules of first-stage and fourth-stage juveniles are smooth, whereas those of the second-stage and third-stage juveniles have faint, bead-like ornamentation either throughout the body or in the anterior or posterior part only. Detailed morphometric data of O. cobbi males and all juvenile stages and females of B. inaequale are given.

Redescription of Heterodera fici (Nematoda: Heteroderidae) with SEM Observations

Heterodera fici is redescribed and illustrated with comparative details and revised measurements and diagnostic characters of the females, males, cysts, and juveniles from Maryland and Pakistan. This species is in the "schachtii group" (cysts lemon shaped, with bullae, and ambifenestrate) but the fenestrae in some cysts, presumab!y young ones, are small and widely spaced, appearing bifenestrate. It is most closely related to H. schachtii, H. glycines, and H. cajani but differs from these species especially in having cysts with small, scattered bullae and weakly developed underbridge; and males with four small nipples on tail tip. Scanning electron microscopy (SEM) observations of the specimens are also presented. The relationship of this species to closely related forms is discussed.

Criconemella spp. in Pennsylvania Peach Orchards with Morphological Observations of C. curvata and C. ornata

Criconemella xenoplax and C. curvata, previously associated with decline of peach trees in other parts of the United States, were found in 20 of 25 Pennsylvania peach orchards. Population densities were high in some samples. Morphometrics of juveniles and adult females of Criconemella curvata and C. ornata, are provided. Cuticular crenations were observed on J2 and J3 stages of C. curvata and J2-J4 stages of C. ornata.

First Report of a Tylenchulus sp. on Peach in Alabama, Arkansas, Georgia, and South Carolina

A Tylenchulus sp. found in a Georgia peach orchard parasitized peach roots in the greenhouse. Citrus roots were not parasitized, indicating that the nematode was not the citrus nematode. Morphologically similar populations were found in one peach orchard in Alabama, two orchards in Arkansas, and one in South Carolina. Males were present in the Alabama populations and one of the Arkansas populations. A population was also found in an area of mixed hardwood and pine in Arkansas. The populations are morphologically different from the citrus nematode Tylenchulus semipenetrans.

Descriptions of Two New Species of Tylenchorhynchus Cobb, 1913 (Nematoda: Tylenchida), with Details on Morphology and Variation of T. claytoni

Two new species of plant parasitic nematodes (Tylenchorhynchus quaidi n. sp. and T. tritici n. sp.) from Pakistan are described and illustrated. Tylenchorhynchus quaidi n. sp., from soil around roots of potato (Solanum tuberosum) from an experimental field of NNRC, Karachi, Pakistan, is distinguishable from other species by its peculiar sunken dome-shaped head. Although similar to T. goffarti, it differs by head shape, areolation of lateral field, ratios a (23-28 vs. 29-37) and c (11-14 vs. 13-20), and a vagina that is half sclerotized and half unsclerotized. Tylenchorhynchus tritici n. sp., from soil around roots of wheat (Triticum aestivum) from Campbellpur, Pakistan, is similar to T. ventrosignatus and T. nordiensis. It differs from T. ventrosignatus by a continuous lip region, number of head annules (2-3 vs. 4), coarse body annulation, absence of a wave-like structure near the vulva, and by tail shape and number of tail annules (15-23 vs. 28-32). It differs from T. nordiensis by stylet length (12.4-14.6 vs. 11-13 mum), shape of stylet knobs, number of head annules (2-3 vs. 4), non-areolated lateral field in region of phasmids, and not fusing in posterior third of tail. Morphometrics of Tylenchorhynchus claytoni from soil around stunted maize (Zea mays L.), in Muscatine County, Iowa, and several other populations are given. Detailed morphometric data on T. claytoni based on topotypes collected from type locality and several other populations revealed that this species shows variations in the shape of tail in females, number of tail annules (and sometimes annules extending further back on the terminus, almost being an annulated terminus), position of phasmid, and shape of lip region. The subgenus Bitylenchus is proposed as a new synonym of Tylenchorhynchus and its species referred to the latter genus.

Description of Dolichodorus cobbi n. sp. (Nematoda: Dolichodoridae) with Description of Dolichodorus cobbi n. sp. (Nematoda: Dolichodoridae) with Morphometrics and Lectotype Designation of D. heterocephalus Cobb, 1914

Dolichodorus cobbi n. sp. is described and illustrated from soil around roots of "woods" on the Stanley Farm, Scott County, Arkansas. This species is distinguishable from others of the genus by its short tail projection. It is most closely related to D. marylandicus but differs in having a short tail projection, longer stylet, greater body length, larger c value, and also in position of excretory pore. A limited number of Cobb's original specimens and drawings of D. heterocephalus were examined. A lectotype and paralectotype were designated to establish the taxonomic base for the genus. Cobb's original modified labeled drawing of D. heterocephalus is also included. Morphometric data on D. heterocephalus from the type locality and several other populations are given. Some variations in female tail shape, body length, and stylet length were noted.

Description of Meloidogyne christiei n. sp. (Nematoda: Meloidogynidae) from Oak with SEM and Host-Range Observations

Meloidogyne christiei n. sp. is described and illustrated from turkey oak (Quercus laevis) in Sanlando Park, Altamonte Springs, Florida. This new nematode species has a distinctive perineal pattern commonly with a high, squarish arch and coarse broken striae which tend to diverge at various angles, especially in and above the anal area. Female labial disc is indented, forming four points or prongs, unlike other species. Eggs are deposited inside the gall in a tubular, coiled manner. Vaginal muscles are exceptionally prominent and dense. SEM observations provided further detail of the perineal pattern and details of the head of females, males, and second-stage juveniles. Galls on the root commonly occur singly, but sometimes in small clusters, and appear as discrete nodules on the side of the root and without adjacent swelling. In general, only one female is found in each gall but occasionally two are present. In greenhouse tests, citrus, tobacco, cotton, pepper, watermelon, peanut, and tomato were not hosts. This nematode occurs throughout central Florida commonly on Q. laevis, the only known host.

Description of Meloidoderita polygoni n. sp. (Nematoda: Meloidoderitidae) from USA and Observations on M. kirjanovae from Israel and USSR

Meloidoderita polygoni n. sp. is described and illustrated from roots of smartweed (Polygonum hydropiperoides) from Beltsville, Maryland. This new species is similar to M. kirjanovae but differs especially in having larger spines on the cystoid bodies, females with the anus much closer to the vulva, and more posterior excretory pore. M. polygoni differs from M. safrica particularly in having females with a shorter stylet, a DGO much closer to base of stylet, greater distance between vulva and anus, and larger cystoid bodies. LM and SEM observations showed only three incisures in lateral fields of juveniles and males and no bursa in males. Morphometric data and illustrations are given for M. kirjanovae from mint (Mentha longifolia) in Israel and some details on a limited number of specimens from Armenian SSR. LM examination of juveniles from both these areas indicated only three incisures in lateral fields. Males from Israel had no detectable bursa and appeared to have only three incisures in lateral fields. (Males from Armenian SSR not observed.).

Redescription of Xiphinema americanum Cobb, 1913 with Comments on Its Morphometric Variations

Xiphinema americanum is redescribed and illustrated from material collected from Arlington Cemetery, near Cobb's type locality (Falls Church, Virginia), Morphometric data showing variations within this species are given for three additional populations.

Description of Thecavermiculatus andinus n.sp. (Meloidoderidae), a Round Cystoid Nematode from the Andes Mountains of Peru

Thecavermiculatus andinus n.sp. is described and illustrated from Oxalis tuberosa originally collected in the vicinity of Lake Titicaca high in the Andes mountains of southern Peru. This new species differs markedly front the other two species in the genus, especially in having a much greater female vulval-anal distance and annules with lined punctation on most of the female body with a lacelike pattern restricted to the posterior portion, particularly at the vulva and anus which do not protrude. Females are essentially spherical with protruding neck, white to yellowish in color, and can easily be mistaken for potato cyst nematodes. Among the dozen or more known weed and crop host plants are potato and eggplant. In order to accommodate this new species, the genus Thecavermieulatus is emended. A key to the species of this genus is presented.

Redescription of Heterodea zeae, the Corn Cyst Nematode, with SEM Observations

Heterodera zeae, the corn cyst nematode, is redescribed and illustrated with comparative details and measurements of females, cysts, and larvae from Maryland, USA; and India. Scanning electron micrographs o f specimens from the United States are also presented. Revised measurements for the larval stylet and new diadnostic characters, especially in the cyst cone, for H. zeae are given. The relationship of H. zeae to close species is discussed.

An illustrated key to the cyst-forming genera and species of heteroderidae in the Western hemisphere with species morphometrics and distribution

Diagnoses of the cyst-forming genera of Heteroderidae (viz., Heterodera, Sarisodera, Globodera, Punctodera, Cactodera, and Dolichodera) and distribution and morphometrics of the 34 known cyst species in the Western Hemisphere are presented along with an illustrated key for the identification of these genera and species. The key is based mainly on cysts and larvae, and important morphological and diagnostic features are extensively shown by LM and SEM illustrations. The genus Bidera is placed as a new synonym under the genus Heterodera.

Morphological Comparisons Between Xiphinema rivesi Daimasso and X. americanum Cobb Populations from the Eastern United States

Though in the past Xiphinema americanum has been the most commonly reported dagger nematode in the eastern United States, our studies revealed the presence in Pennsvlvania of a previously unrecognized and unreported species related to X. americanum, Morphometric data and photomicrographs establish the identity of this form as X. rivesi and show expected variations in populations of this species from various locations. Similar data and illustrations are given for X. americanum populations from Pennsylvania and other areas, showing variations and relationships. Xiphinema rivesi is widely distributed in the fruit producing area of south-central Pennsylvania and is also reported herein from raspberry in Vermont and apple in Maryland and New York. This species is frequently found in fruit growing areas of Pennsylvania associated with tomato ringspot virus-induced diseases and is also found associated with corn, bluegrass sod, and alfalfa.

Redescription and Lectotype Designation of Tylenchorhynchus cylindricus Cobb, 1913

Tylenchorhynchus cylindricus is redescribed and illustrated from N. A. Cobb's original specimens collected in 1910. In 1955 M. W. Allen established a neotype from specimens collected near Cathedral City, California. Recently Cobb's original sketches, line drawings, and balsam slides were rediscovered and examined. The specimens collected by Cobb were compared with the neotype established by Allen and with other collections of nominal T. cylindricus. Differences in morphology of the Cathedral City (Allen) and Los Patos (Cobb) populations were observed. Collections of males and females from Cathedral City, California; Mosida, Utah; and Kings County, California; were similar to each other except for some variation in female tail shape. Females in Cobb's collection and in a collection from a beach near Ensenada, Mexico, were similar to each other but differed morphologically from other collections. We consider all collections to represent a range of variation within the species. A lectotype and an allolectotype were selected to establish the taxonomic base for the genus. A ruling has been requested from the International Commission of Zoological Nomenclature on the disposition of the neotype.

Description of Meloidogyne nataliei n. sp. (Nematoda: Meloidogynidae) from Grape (Vitis labrusca) in Michigan, with SEM Observations

Meloidogyne nataliei n. sp. is described and illustrated from grape (Vitis labrusca) in a declining vineyard at Mattawan, Michigan, USA. Infected grape roots exhibit no hyperplastic symptoms. Females protrude from the roots and are surrounded by a massive egg sac containing many eggs. This new species is distinguishable from other species of the genus especially by its large, striking perineal pattern with, usually, two ropelike separated striae on each side extending laterally from the vulval and anal areas. Among other diagnostic characters are the location of the female excretory pore adjacent to or near the base of the head and the heavy larval stylet averaging about 22 mum in length. Examination of males, females, and larvae with the scanning electron microscope confirmed observations made by optical microscopy and revealed diagnostic and other structures in greater detail. Of particular significance was the nature of the male head, with a massive circular labial disc on which is located a rectangular structure surrounding the oral opening, and the six distinct lips appearing as a rosette in en face view. The known distribution of this new species is presently limited to its original location in Michigan.

On the Taxonomy and Morphology of the Pine Wood Nematode, Bursaphelenchus xylophilus (Steiner &Buhrer 1934) Nickle 1970

During the past 3 yr, nematologists in the United States have found specimens of Bursaphelenchus sp. in the wood of dead and dying pine trees. This nematode-host association resembles a similar interaction reported from Japan where pine trees are being killed by the pine wood nematode. This taxonomic research was conducted to determine if the Japanese pine wood nematode and similar populations in the United States are of the same species. Based upon typical morphological characters of original specimens of Bursaphelenchus xylophilus (Steiner and Buhrer 1934) Nickle 1970 that were rediscovered in the USDA Nematode Collection and genetic crosses among the Japanese and American nematode populations, it was concluded that they are all the same species, B. xylophilus.

Description of Trilineellus clathrocutis n.g., n.sp. (Tylenchorhynchinae: Tylenchida Thorne, 1949) with a Key to Species and Observations on Tylenchorhynchus sensu stricto

TrilineeIlus clathrocutis n.g., n.sp. is described and illustrated. It was found as an associate of corn (Zea mays) in Stockton, Georgia, USA, and is related to a group of Tylenchorhynchus sensu lato species having three lines in nonareolated lateral fields. This new species is closely related to Tylenehorhynehus divittatus Siddiqi 1961, T. sculptus Seinhorst 1963, and T. triglyphus Seinhorst 1963 (syn. T. chonai Sethi & Swarup 1968) Tarjan 1973. It differs from these species primarily by having longitudinal striae on the body. These four species are differentiated from Tylenchorhynchus sensu stricto by having three lateral lines instead of four. They differ from Uliginotylenchus Siddiqi 1971 by having nonareolated lateral fields, fewer than 25 annules on conoid rounded tails, differently shaped gubernacula, nonattenuated stylets, and other distinctive characters. They differ from Triversus Sher 1973 by having the male tail enclosed by the bursa and by having rounded female tails. SEM observations of T. clathrocutis reveal a cuticle deeply cut by longitudinal and horizontal striae and bearing wide (> 2.0 mum) annules. Trilineellus is proposed to accommodate the new species and the three-incisured species still within Tylenchorhynchus. Tylenchorhynchus is thereby the repository for species within Tylenchorhynchinae having four lines in the lateral field, no conspicuous labial disc, and bursa enclosing the male tail.

Description and SEM Observations of Dolichodorus marylandicus n. sp. With a Key to Species of Dolichodorus

Dolichodorus marylandicus n. sp. is described and illustrated from grass (Zoysia japonica) in College Park, Maryland. Specimens have also been collected from perennial bluegrass (Poa pratensis) pasture at Beltsville, Maryland, and from pine (Pinus sp.) in North Carolina. This new species is related to D. heterocephalus Cobb, D. similis Golden, and D. aestuarius Chow &Taylor. Females are distinct in having a longer styler and shorter body length than D. aestuarius. The excretory pore is at the level of the isthmus or slightly posterior and the tail is abruptly reduced in diameter, tapering to an acuminate terminus. The tails of D. similis and D. heterocephalus conically taper to a median point, with D. similis having an especially long tail. D. marylandicus does not possess the rounded, sclerotized accessory structures adjacent to the vulva observed in lateral views of D. similis and D. heterocephalus. SEM observations of D. heterocephalus and D. marylandicus revealed details of the head of males and females, and species difference in shape of the oral disc.

Description and SEM Observations of Meloidogyne chitwoodi n. sp. (Meloidogynidae), a Root-knot Nematode on Potato in the Pacific Northwest

Meloidogyne chitwoodi n. sp. is described and illustrated from potato (Solanum tuberosum) originally collected from Quincy, Washington, USA. This new species resembles M. hapla, but its perineal pattern is basically round to oval with distinctive and broken, curled, or twisted striae around and above the anal area. The vulva is in a sunken area devoid of striae. Vesicles or vesicle-like structures are present in the median bulb of females. The larva tail, being short and blunt with a hyaline tail terminal having little or no taper to its rounded terminus, is distinctively different from M. hapla. SEM observations revealed the nature of the perineal pattern and details of the head of larvae and males, and showed the spicules to have dentate tips ventrally. Hosts for M. chitwoodi n. sp. include potato, tomato, corn, and wheat but not strawberry, pepper, or peanut. The latter three crops are excellent hosts for M. hapla. The known distribntion of this new root-knot species presently involves certain areas of Idaho, Washington, and Oregon. The common name "Columbia root-knot nematode" is proposed for M. chitwoodi n. sp.

Descriptions of Meloidogyne camelliae n.sp. and M. querciana n.sp (Nematoda:Meloidogynidae), with SEM and Host-Range Observations

Meloidogyne camelliae n.sp. on camellia (Camellia japonica) from Japan and M. querciana n.sp. on pin oak (Quercus palustris) from Virginia, USA, are described and illustrated. M. camelliae n.sp. is distingnishable from other species of the genus especially by its striking perineal pattern having heavy ropelike striae forming a squarish to rectangular outline with shoulders or projections, appearing sometimes ahnost starlike. M. querciana differs from other species by its characteristic perineal pattern round to oval in outline, sometimes with a low arch, and sunken vulva surrounded by a prominent obovate area devoid of striae. M. querciana shows some relationship to M. ovalis, but differs further fxom the latter by longer larvae, absence of annules on head of larvae, and rarity of males. Examination of specimens of M. camelliae n.sp. and M. querciana n.sp. with the scanning electron microscope confirmed observations made by optical microscopy and revealed diagnostic and other structures in greater detail. In greenhouse host tests, M. camelliae infected camellia heavily, showed moderate infection on oxalis, only a trace infection on tomato, and no infection on five other plants tested; and M. querciana attacked pin oak, red oak, and American chestnut heavily, but did not infect nine other test plants. In another test, pin oak seedlings did not become infected when heavily inoculated with and grown in the presence of two populations of M. incognita incognita and one of M. incognita acrita. The common names "camellia root-knot nematode" and "oak root-knot nematode" are respectively proposed for M. camelliae and M. querciana.

Helicotylenchus oleae n. sp. and H. neopaxilli n. sp. (Hoplolaimidae), Two New Spiral Nematodes Parasitic on Olive Trees in Italy

Helicotylenchus oleae n. sp. and H. neopaxilli n. sp., from olive roots and soil in Italy, are described and illustrated. Helicotylenchus oleae can be distinguished from the related species H. canadensis and H. tunisiensis especially by the smaller styler, its distinctive tail shape, and a tail longer than one anal body width. Helicotylenchus neopaxilli differs from the close species H. paxilli by having a conical, anteriorly truncated labial region, shorter stylet, and phasmids always anterior to level of anus. Also illustrated and discussed are histopathological changes within feeder roots of olive caused by the feeding activity of the semi-endoparasitic H. oleae.

Meloidogyne grahami n. sp. (meloidogynidae), a root-knot nematode on resistant tobacco in South Carolina

Meloidogyne grahami n. sp. is described and illustrated from specimens on tobacco (Nicotiana tabacum) originally from Florence, South Carolina. Considered for several years to be only a race of M. ineognita, this new species readily attacks NC-95 tobacco, a variety with resistance to the M. incognita group that is common in the major U.S. tobacco-producing areas. M. grahami n. sp. is related most closely to the three subspecies of the M. incognita group but differs from all of them, especially in its distinctive perineal pattern and larger larvae (av. 421 microm, vs. 385 microm or less). Also, the dorsal esophageal gland orifice of females of M. grahami n. sp. is further from the base of the styler (5 microm) than in M. i. incognita and M. i. acrita. Comments are given on the distribution of this new species.

Meloidogyne incognita wartellei n. subsp. (Meloidogynidae), a Root-knot Nematode on Resistant Soybeans in Louisiana

Meloidogyne incognita wartellei n. subsp, is described and illustrated from roots of soybean (Glycine max L.) near Washington, Louisiana. It is rather limited in distribution in that state, being known at five locations comprising about 60,000 acres. It not only attacks commonly susceptihle soybeans but is a destructive pest on other commercial soybean varieties that are resistant to other forms of the M. incognita group in the area. This new subspecies is related most closely to M. i. incognita and M. i. acrita, but differs especially in the females having a delicate stylet with small, rounded knobs sloping posteriorly; dorsal esophageal gland orific further back (5 mum) from base of stylet; and excretory pore often two to three stylet lengths (sometimes more) from the anterior end. Also, males are often without detectable head annules and with an average stylet length of 22.4 mum. Comments and morphometric data are given on M. i. incognita and M. i. acrita.

Heterodera thornei n. sp. (Nematoda:Heteroderidae) and a review of related species

In a taxonomic review of the species of the Heterodera "cacti group," H. thornei n. sp. is described and illustrated from Miner's lettuce in California. This new species is distinguishable especially by havpunctate egg shells and a larval stylet (27 mum) and tail (56 mum) longer than other related species. Heterodera weissi is redescribed, type specimens are designated, and new data added on the basis of original and topotype specimens. New morphometric data, along with illustrations, are given for H. cacti, H. amaranthi, and H. estonica, and certain details in the original descriptions are clarified on the latter two species. Diagnoses and a key for identification of these species are given. A common name for each species is proposed when one is lacking. Previously unrecognized tooth-like structures occurring in the vulval cone top of these species and in H. schachtii are characterized and named "vulval denticles." Because of its markedly different morphology, especially in cysts, H. betulae is removed from the H. cacti group and placed alone, since it is incompatible with any of the present Heterodera "groups." Know distribution of these species is given, with the result that many new areas and countries of occurrence for some of the species are listed.

Nacobbodera chitwoodi, n. gen., n. sp., (Nacobbidae:Nematoda) on Douglas Fir in Oregon

Nacobbodera chitwoodi, n. gen., n. sp., representing Nacobboderinae n. subfam, in the Nacobbidae, is described and illustrated from roots of Douglas fir, Pseudotsuga menziesii near Florence Oregon. This new species, having characters common to Nacobbidae, Heteroderidae, and Meloidogynidae, appears to represent a connecting link between these three families of the Heteroderoidea. Especially, a distinct tail on swollen adult females, vermiform shape of juvenile females, and the shape and sclerotization of the head of the various stages, indicate a Nacobbidae relationship. Certain other characteristics present in this new species are of the Heteroderidae and Meloidogynidae type as follows: Gross shape of adult female in posterior half of body, two ovaries, anterior position of excretory pore as in Meloidogyne females, absence of a bursa, and development of male within a sausage-shaped cuticle as in root-knot and cyst nematodes.

Heterodera achilleae n. sp. (Nematoda: Heteroderidae) from Yarrow in Yugoslavia

Heterodera achilleae n. sp., a member of the H. rostochiensis group, is described and illustrated from roots of yarrow, Achillea millefolium L. in Sarajevo, Yugoslavia. This new, round-cyst species differs from closely related species especially as follows: (1) from H. leptonepia, by having stouter larvae (a = 21), with longer styler (25 mu), and with outlet of dorsal esophageal gland averaging 5.7 mu from base o f styler; (2) from H. millefolii, in having excretory pore at base of neck and small, straight vulval slit of 5 mu; (3) from H. rostochiensis, in having a B/A ratio (Granek's ratio) of 1.6 ; (4) from H. tabacum, by longer female stylet, two annules on female head, and males with outlet of dorsal esophageal gland further back (5.7 mu). In addition, H. achilleae n. sp. differs from the latter three species in having prominent longitudinal striae on the anterior half, or more, of cysts and females.

Heterodera longicolla, n. sp. (Nematoda: Heteroderidae) from Buffalo-grass (Buchloë dactyloides) in Kansas

Heterodera longicolla n. sp., a member of the H. goettingiana group, is described and illustrated from roots of buffalo-grass, Buchloë dactyloides (Nutt.) Engelm., in Manhattan, Kansas. This new abullate species, having second-stage larvae with only three lines in the lateral field, is most closely related to H. cyperi Golden, Rau & Cobb, 1962, but differs particularly in having a shorter stylet in larvae, males and females; in possessing only three annules on the head of larvae and males; in having a shorter tail in larvae; and by the presence on cysts of a small anus without a circum-anal pattern.

Heterodera graminophila n. sp. (Nematoda Heteroderae) from Grass with a Key to Closely Related Species

Heterodera graminophila n. sp., a member of the H. goettingiana group, is described and illustrated from roots of barnyard grass, Echinochloa colonum (L.) Link, in Baton Rouge, La. This new abullate species, having second-stage larvae with only three lines in the lateral field, is most closely related to H. cyperi Golden, Rau &Cobb, 1962, and H. graminis Stynes, 1971, but differs particularly in having a small, inconspicuous anus without a circum-anal pattern and located about 20% of the cyst length from the vulval cone terminus, and a longer vulval slit averaging 45 mu in length. A key, based on cyst and larval characters, is presented for identification of the 10 Heterodera species in the H. goettingiana group.

Description and Larval Heteromorphism of Hoplolaimus concaudajuvencus, n. sp. (Nematoda: Hoplolain-lidae)

Hoplolaimus concaudajuvencus n. sp., of the genus Hoplolaimus Daday, 1905, characterized by larval heteromorphism, is described and illustrated as recovered from ryegrass/bermudagrass golf green turf in Florida. Females and males are closely related to H. galeatus (Cobb, 1913) Thorne, 1935, but have longer stylets with more definitely tulip-shaped stylet knobs which anteriorly tend to close upon the stylet shaft more than in H. galeatus. First and second-stage larvae have a conically-pointed tail unlike any known species of the genus. Subsequent stages, including females, have rounded tails essentially similar to other species of the genus and males possess the typical hopolaimid tail and bursa. The first molt was found to occur within the egg.