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Several plant parasitic nematode genera were identified in the Robusta coffee ( Coffea canephora Pierre ex A. Froehn) tree roots and surrounding soil samples from three different coffee groups: coffee planted at 5 years (CYG), 18 years (CBG) and 40 years (COG) in Central Highland, Vietnam. They included Meloidogyne spp., Pratylenchus spp., Apratylenchus spp., Criconemella spp., Xiphinema spp. and Rotylenchulus spp. Meloidogyne spp. was the most abundant genus, at 77% across all three groups. Endophytic bacteria were isolated from healthy tissues of roots of the same Robusta coffee trees. In total, 77 bacterial strains were isolated and determined to be Bacillus spp., Serratia spp., Paenibacillus spp., Enterobacter spp. and Streptomyces spp. based on colony morphological and 16S rRNA gene sequence analysis. Overall, Streptomyces was the dominant genus and accounted for 49.35% of total isolated strains. Using statistical methods, we found a tendency in the abundance of endophytic bacterial isolates with the elevation or decrease of several nematode populations, indicating a relation between endophytic bacteria occurrence and nematode distribution. In in vitro anti nematode screening test, a Streptomyces sp. strain named CBG9 showed significant nematicidal activities against Meloidogyne incognita , inhibiting egg hatching (85.8%) and causing mortality of secondary stage juveniles (85%). This study explored the anti-nematode potency of endophytic bacteria isolated from coffee trees, which could provide a future application in suppression and management of pathogenic nematodes without the use of chemical pesticides.

Golf courses in coastal regions of northern California are often faced with severe injury caused by pacific shoot-gall nematodes ( Anguina pacificae ) on their annual bluegrass ( Poa annua ) host in putting greens. For years, fenamiphos was used for mitigating disease outbreaks until its registration was withdrawn in 2008. An alternative product containing azadirachtin was intended for nematode suppression. Still, it required repeated applications throughout the year with questionable efficacy, making attempts to lessen the impact of the pathogen costly. This study evaluated fluopyram as a novel nematicide for control of pacific shoot-gall disease. Various application frequencies and rates were tested at several golf courses affected by the nematode. Results revealed that fluopyram applied once at 0.22 lb/acre reduced the number of new shoot-galls and improved annual bluegrass appearance for several months. Increased rates and application frequency occasionally improved the efficacy further. Although the visual quality of turf treated with this plant protection compound was tremendously enhanced, and the number of new shoot-galls was reduced, rarely a significant effect was observed on the population density of several soil-dwelling plant-parasitic nematodes, including pacific shoot-gall nematode. It is hypothesized that fluopyram did not move significantly past the thatch layer and into the soil. However, it effectively reduced the ability of pacific shoot-gall nematode juveniles to induce new shoot galls. Due to its long half-life, it likely protected against both new nematode infections and dissemination of pacific shoot-gall nematode when the shoot-galls decomposed.

Since 1885, plant parasitic nematodes have been reported in Indonesia, and somewhere recorded in older nomenclatures. Taxa status of the nematode should be reevaluated, since classification of the nematode might be changed by the consensus of some taxonomist based on the newest nematode morphological and or molecular phylogenetic differences. The objective of this work is to clear the confused older nematode nomenclature through nomenclatorial observations from older and modern description literatures, and updated electronic data (CABI, EPPO). From nomenclatorial observation results, earlier period recorded Heterodera sp. on wild tamarind and silk tree, Heterodera marioni on Coffea sp. and quinine plant, Heterodera radicicola on Coffea sp. and sweet potato are the presently genus Meloidogyne sp. and Heterodera javanica is the presently Meloidogyne javanica; Tylenchus similison black pepper and tea are the presently species of Radopholus similis; Tylenchus coffeae on silk tree and Coffea sp. and Tylenchus pratensis Filip on Coffea sp. are the same presently species Pra Tylenchus coffeae; while Radopholus oryzae on paddy, is the presently species Hirschmanniella oryzae; and ring nematode, Macrophostonia ornata on black pepper and Criconemella ornata on citrus, are the same presently species, Mesocriconema ornata; and Criconemella sp. on black pepper is presently Mesocriconema sp.

Rhododendron dieback was continuously observed with increasing frequency on Rhododendron maximum (Rosebay Rhododendron) during the last 20 years in the southern Appalachian Mountains. The dieback was especially evident following several years of drought from 2004 to 2008 recorded in Great Smoky Mountains National Park (GRSM). With the concern that a disease epidemic could occur, a holistic study evaluated site factors including tree health, number of clonal units, aspect, slope, depth to bedrock, and rhizosphere microbes. This study was conducted at two locations: Laurel Falls in GRSM and Albert Mountain in Nantahala National Forest (NNF). Yearly sampling for nematodes showed no differences in frequencies across or between years. A total of 11 species were identified from replicated healthy and dieback plots with no significant trends observed. Criconemella xenophus, Helicotylenchus sp., and Meloidogyne sp. were the species most commonly found. Belonolaimus sp. occurred at the NNF site at below 1% of the total nematode population identified, but this nematode species is considered damaging to crops and forest nursery seedlings even at low numbers. Fungal/Oomycota diversity and densities were determined from roots and rhzosphere soil samples using three identification methods. The results ranged from 110 species of fungi to 0 for Oomycota. Of 110 fungi isolated, one putative root pathogen was identified, and the saprophytic species Mycena silvae-nigrae (unknown Basidiomycota 1) was the most common match using the GenBank database. Elevation at NNF was significantly greater than at GRSM, with significantly greater dieback levels at the higher elevation. Furthermore, greater dieback ratings were associated with significantly greater tree diameters. No trends were observed for percent slope or nutrient levels when compared between healthy and dieback sites or locations. Site factors such as aspect, elevation, associated nematode species, and a putative root pathogen may form a disease complex resulting in Rosebay Rhododendron dieback.

As part of the All Taxa Biodiversity Inventory (ATBI) of Great Smoky Mountains National Park (GRSM), select site parameters associated within upland sites were measured within variable sized pockets of stressed and dead Rhododendron maximum (Great Rhododendron). During the last 20 years, Great Rhododendron, an important shrub in the southern Appalachian Mountains, has been dying in small to larger areas from an unknown cause. With increased visibility of dieback, the study (2006–2009) was conducted at 10 sites in GRSM and 1 in Nantahala National Forest (NNF). Eleven nematode species were identified, with no specific trends across locations or by plot treatments in frequencies of occurrences. Exceptions were Criconemella xenoplax, which was found at all 11 locations and was generally significantly greater in healthy or control than dieback plots, whereas Helicotylenchus sp. was more frequent in dieback plots. Meloidogyne spp., known parasitic nematodes of woody plants and agricultural crops, occurred in over 50% of the locations; Hoploliamus sp. occurred at 40%; and Belomolaimus sp., which are very destructive to root systems, were found at low levels at the NNF site. Also, Heterodera sp. occurred in control and dieback plots in 10 of the locations. Dieback ratings were not significantly correlated to stem diameter; although the finding was not statistically significant, six of seven sites with dieback plots had numerically greater-sized stems than in the controls. No other parameters such as number of clonal units, site aspect, percent slope, or elevation showed any trends at both sites. Nutrient data did not indicate any specific relationships to plot damage or health. This study provides the first comprehensive reporting of nematode species that occur in Great Rhododendron and associated riparian and upland sites. With concerns of global climate impacts, this research provided additional baseline data for the ATBI of GRSM and NNF.

Numerous genera of plant-parasitic nematodes are frequently present at high populations in golf course putting greens. The objectives of this research were to identify and quantify plant-parasitic nematodes from Oklahoma bentgrass putting greens and to characterize specific soil physical and chemical features and management factors that may account for differences in or associated with the observed nematode populations. In the fall of 2000, nematodes were identified from 99 individual bentgrass putting greens sampled from 46 different locations in Oklahoma. In addition to green age and bentgrass cultivar; soil pH, nitrate-nitrogen (NO 3 -N), plant-available phosphorus and potassium, organic matter (OM), bulk density, and particle size distribution were determined for each green. Expenditures on management activities, including fertilizer, herbicide, fungicide, and insecticide, were determined for 20 of the sampled courses and compared with nematode populations. Nematodes from seven genera were found in Oklahoma greens, with Criconemella spp. being the most common. Paratrichodorus spp., Tylenchorhynchus spp., and Helicotylenchus spp. also were common. The logarithmic populations of all nematodes combined increased with greater green age (r = 0.37). A negative relationship was observed between soil bulk density and all nematodes combined (r = -0.29). Soil NO 3 -N, plant-available K, and OM increased with combined logarithmic populations of all plant parasitic nematodes (r = 0.23, 0.28, and 0.37, respectively). A four-factor model accounted for 75% of the total variation in the data and permitted groupings of all variables into four uncorrelated factors. Total logarithmic nematode populations increased with fungicide and herbicide expenditures (r = 0.31). This study suggests that populations of plant-parasitic nematodes may be influenced by the putting green abiotic soil environment and possibly indirectly by management practices on putting greens.

Mineral fertilizer application and consequent plant nutrition has long been observed to influence associated plant-parasitic nematode population densities, offering the potential as a nematode management option. Observations were made on the influence of mineral fertilizer application on nematode populations on three separate long-term rice experiments, (differential mineral application on upland and on lowland rice, and P application on upland rice) undertaken between 1994 and 1997 in Côte d'Ivoire. In 1995, on upland rice, treatments with K or N withheld from the comprehensive mineral application treatment (range of elements including N, P, K, Ca, Mg and Zn) led to lower densities of Pratylenchus zeae at harvest than the comprehensive mineral application. By withholding K or Mg, Helicotylenchus pseudorobustus densities were greater than with either the control (no mineral application) or comprehensive mineral application in the same year. No differences were observed between treatments in 1994, or between treatments for densities of other nematode species present (Meloidogyne incognita, Criconemella tescorum) or for total nematode density. In the lowland rice trial, no treatment effects on nematode species (Hirschmanniella oryzae and Uliginotylenchus palustris) were observed. In the P application trial on a P-deficient Ultisol, Heterodera sacchari densities were lower in treatments receiving 180 kg P ha−1, than untreated in 1995; in 1996 no differences were observed between untreated and 135 kg P ha−1, while in 1997 higher densities of H. sacchari were present in 135 kg P ha−1 than untreated. Regression analysis of nematode densities against the mineral straw content in the P application trial revealed a negative correlation between M. incognita and Mn and Ca, and between P. zeae and Zn or Fe. A positive correlation was observed between Helicotylenchus spp. and Mg. This study provides strong arguments for taking plant parasitic nematodes into account when planning and executing long-term research trials.

The increasing use of integrated crop management, often requiring a reduction in the reliance upon chemical control, means that the need to rapidly identify pest nematodes has never been greater. This second edition of this standard reference work familiar to all plant nematologists is therefore even more useful than its predecessor published in 1986.The in-depth description of the life histories of the genera of the Tylenchida have been retained and brought up-to-date through the inclusion of all the research carried out between the publication of the last edition and this new edition. This expanded edition includes detailed diagnoses of well over 200 genera and familial and ordinal groups, and is well-illustrated with drawings of type or representative species. These, together with comprehensive lists of species and genera and their synonymies provide the foundation for the status and validation of each taxon within the Tylenchida. A considerable amount of information is provided regarding the biology, ecology and pathogenicity of these parasites.

Spatial sampling was used to investigate temporal density-dependent parasitism of the plant-parasitic nematode Criconemella xenoplax by Hirsutella rhossiliensis in three peach orchards on eight sample dates. The patches of soil in which the nematode and fungus interacted were assumed to possess similar density-dependent dynamics and to be small, independent, and asynchronous. Furthermore, sampling of separate patches was assumed to provide similar information with respect to density dependence as would temporal (repeated) sampling of the same patch. Percent parasitism was dependent on the number of C. xenoplax/100 cm3 soil (P = 0.0001). The slope was unaffected by orchard or date but ranged from 0.0001 to 0.0043 depending on distance from the irrigation furrow. The relative shallowness of the slope and the large variation in percent parasitism not explained by nematode density suggest that H. rhossiliensis is a weak regulator of C. xenoplax population density.

Distribution of plant-parasitic nematode species at soil depths of 0-15 cm, 15-30 cm, and 30-45 cm was examined in two maize fields in Florida during 1987 and 1988. Soil type in both fields was an Arredondo fine sand, consisting of 94-96% sand at all three depths. On most sampling dates, more than 50% of the Belonolaimus longicaudatus collected occurred at the 0-15 cm depth. Only 20-30% of Criconemella sphaerocephala were present at this depth, and the depth distribution of this nematode differed in the two fields. The greatest densities of Pratylenchus brachyurus often occurred at 15-30 cm. Vertical distributions of Meloidogyne incognita and Paratrichodorus minor were erratic and showed marked seasonal variation. For all species examined except B. longicaudatus, a diagnostic soil sample collected 15 cm deep would recover only a minority of the nematode population present in the soil profile.