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BACKGROUND: This report describes activity against Meloidogyne spp. and chemical characterisation of the essential oil and methanol extract of Petroselinum crispum aerial parts. The study was based on the hypothesis that P. crispum could be used as an intercrop and soil amendment in tomato culture for nematode control. RESULTS: The methanol extract and the essential oil exhibited significant nematicidal activity against M. incognita, M. hapla and M.arenaria, the first being the most sensitive species, with EC50/72 h values of 140± 15 and 795 ±125mgL-1 for the extract and oil respectively. The most abundant furanocoumarin compounds in the methanolic extract were xanthotoxin, psoralen, bergapten and oxypeucedanin; levels ranged from 1.77 to 46.04mgkg-1 wet weight. The EC50/24 h values of xanthotoxol, psoralen and xanthotoxin against M. incognita were 68±33, 147±88 and 200±21mgL-1 respectively. The addition of fresh parsley paste to soil reduced the number of M. incognita females and plant galls on tomato roots; EC50 values were 24.79 and 28.07mgg-1 respectively. Moreover, parsley paste enhanced tomato growth in a dose-response manner. CONCLUSIONS: Parsley exhibits promising nematicidal activity as an organic amendment and as a source of nematotoxic furanocoumarins. [ABSTRACT FROM AUTHOR]

The following account is based on a review lecture given recently at the British Society of Parasitology. We point out that nematode parasites cause very widespread infections of humans, particularly in economically underdeveloped areas where sanitation and hygiene are not adequate. In the absence of adequate clean water and effective vaccines, control and prophylaxis relies on anthelmintic drugs. Widespread use of anthelmintics to control nematode parasites of animals has given rise to the development of resistance and so there is a concern that similar problems will occur in humans if mass drug administration is continued. Recent research on the cholinergic anthelmintic drugs has renewed enthusiasm for the further development of cholinergic anthelmintics. Here we illustrate the use of three parasite nematode models, Ascaris suum, Oesophagostomum dentatum and Brugia malayi, microfluidic techniques and the Xenopus oocyte expression system for testing and examining the effects of cholinergic anthelmintics. We also show how the combination of derquantel, the selective nematode cholinergic antagonist and abamectin produce increased inhibition of the nicotinic acetylcholine receptors on the nematode body muscle. We are optimistic that new compounds and combinations of compounds can limit the effects of drug resistance, allowing anthelmintics to be continued to be used for effective treatment of human and animal helminth parasites. [ABSTRACT FROM AUTHOR]

The suppressive effects of palisade grass (Brachiaria brizantha) cv. MGS on Pratylenchus coffeae were tested in pot and seedling tray experiments and under field conditions. In pot tests, four isolates of P. coffeae were tested by inoculating 500 mixed life stages of each isolate on 5- or 7-week-old palisade grass plants. The nematode number in palisade grass was significantly lower than in susceptible cucumber in all isolates and below 20% of the inoculated level 69-86 days after inoculation. In seedling tray tests, the number of eggs and adults + juveniles in palisade grass roots was examined 5-25 days after inoculation (dai) of 200 mixed life stages of an isolate of P. coffeae to a 3-week-old seedling. The number of adults + juveniles in palisade grass roots was not statistically different from sorghum and black oat 5 and 10 dai, while the number of eggs and adults + juveniles was significantly lower than these two plants 20 and 25 dai. In field plot tests, palisade grass was cultivated for approximately 4 months in 2011 and 2012. The P. coffeae density after palisade grass cultivation was significantly lower than that after bare fallow in 2011, whereas the nematode density was not significantly different between these two treatments in 2012. Rates of lesions on sweet potatoes cultivated after growing palisade grass were significantly lower than those after growing sorghum or guinea grass, but not significantly different from that after fallow. These results indicated that the cultivation of palisade grass cv. MG5 has a nematode suppressive effect that is comparable to fallow treatments. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the potential of strains of Trichoderma asperellum, Lieckfeldt & Nirenberg to control M. incognita, (Kofoid and White) Chitwood. Under laboratory conditions (in vitro), six native strains of T. asperellum (Ta.25, Ta.1, Ta.90, Ta.78, Ta.79, and T.13) were selected for their high antagonistic capability, production of various metabolites, and adaptation to different environmental conditions and substrates. For the in vitro trial, 1/10, 1/25, 1/50 dilutions and the pure filtrate of each strain were tested, including a control treatment with sterile water. For the study under semi-controlled conditions, tomato (Solanum lycopersicum L.) plants were inoculated with 2.5 second instar juveniles (J) per gram of soil and, after 72 hours, 107CFU of the strain Ta.90 were added per pot The treatments were: healthy plants (absolute control), plants + Ta.90, plants +Ta.90 + nematodes, plants + nematodes, and nematodes + Ta.90 (without plants). The parameters evaluated after 35 days were galling index (IA), number of eggs per root system, plant height, stem diameter, root length, number of leaves, and weight of fresh root. High mortality levels were shown by all the T. asperellum strain filtrates; the strain Ta.90 stood out with 90% mortality at 24 hours. In the pot trial, this latter strain significantly reduced the number of eggs per female compared with the unapplied control, and attenuated the effect of the nematode on parameters such as plant height, stem diameter, number of leaves, and root fresh weight. [ABSTRACT FROM AUTHOR]

The stem and bulb nematodes of theDitylenchus dipsaci(Kühn) Filipjev species complex are obligate endoparasites of various agricultural plants, causing stunting and swelling and resulting in significant economic losses. Recently, a new closely relatedDitylenchusspecies,D. weischeriChizhov, Borisov and Subbotin, a parasite of the cosmopolitan herbaceous perennial weed,Cirsium arvense(L.) Scop., was described. Many countries impose quarantine restrictions for the presence ofD. dipsaciin imported plant and soil materials. In the current study, we developed PCR with species-specific primers for the rapid and reliable separation ofD. weischeriandD. dipsaciusing gel electrophoresis and melting curve analysis. Species-specific primer sets were designed based on the nucleotide sequence of the heat shock protein (hsp90) gene for both nematode species. The PCR protocol was verified using samples ofD. weischeri,D. dipsaciand the closely related species,D. gigas, which parasitizes broadbean (Vicia fabaL.). The species-specific primer sets were able to detectD. weischeriandD. dipsacifrom samples containing mixtures ofDitylenchusspecies. The PCR species-specific protocol should allow for more rapid identification ofDitylenchusspecies recovered from plant materials than previously possible. [ABSTRACT FROM AUTHOR]

Objective To describe an ovine parasitological monitoring service delivered by a rural veterinary practice and determine associations between flock, anthelmintic and monitoring factors and worm control. Design Retrospective study of records from a rural veterinary practice in south-eastern Australia over an 8.75-year period. Methods Records of sheep producers using veterinary services for gastrointestinal parasite management from 1 August 2003 to 30 April 2012 were analysed. Results from pre- ( FECt1) and post-treatment faecal egg counts ( FECt2) were used to identify factors influencing anthelmintic effectiveness, calculated as faecal egg count reduction percentage ( FECR%) by linear mixed model analyses. The trends in anthelmintic merchandising and uptake of veterinary services for parasite management were determined by logistic regression analyses. Results FECR% varied according to the treatment group used ( P < 0.001), with an apparent decreasing effectiveness of the macrocylic lactone group over the duration of the study ( P = 0.008). Wether and ram flocks displayed lower FECR% than ewe flocks ( P < 0.05). Time between FECt1 and treatment ( P = 0.031), as well as time between treatment and FECt2 ( P < 0.001), had a significant negative association with FECR%. The proportion of properties purchasing 4-way combination anthelmintics increased significantly over the study period ( P < 0.001), with declines observed in other anthelmintics ( P < 0.05). The proportion of properties performing FECR% monitoring to those that purchased anthelmintics increased significantly over the study period ( P = 0.001). Conclusion Anthelmintic treatment type, sex of the flock and time between drenching and testing had the greatest influence on drench effectiveness ( FECR%). An increasing reliance on 4-way combination drenches to manage gastrointestinal parasitism was demonstrated. Benefits of parasitological monitoring include: appropriate advice on parasitological management; observations on trends in regional anthelmintic usage; estimation of drench effectiveness; early indication of anthelmintic resistance; and improved service provision by the rural veterinary practice. [ABSTRACT FROM AUTHOR]

Effective control of plant parasitic nematodes in crop plants will contribute hundreds of millions of dollars to global agriculture and help underpin future food security. Natural nematode resistance genes present in gene pools of crop species and their relatives have long been exploited with the aim of transferring such traits into economically important crops where effective resistance is lacking. Biotechnology also contributes to this process via marker-assisted selection to identify and combine the best nematode resistance genes, and increasingly in providing new knowledge of target genes, and the potential to exploit this knowledge using transgenic technology. Thus recent advances now make it possible to exploit specific aspects of nematode-host plant interactions to design control strategies that include enabling plants to prevent nematode invasion, reducing effectiveness of nematode migration through tissues, preventing successful establishment or reducing feeding ability or nematode fecundity. The knowledge of what genes are vital for successful nematode parasitism can also be used to develop new chemical control agents. These new strategies may either be available for public use or be delivered commercially. For transgenic technologies, both modes of delivery face the same issues in terms of deployment, such as substantial field testing, meeting environmental and human safety regulations, adequate funding to complete statutory requirements, and public acceptance of GMOs when the product is to be marketed. However, as technology develops, new strategies for nematode control are emerging, both for transgenic approaches and in genome editing, which should be regarded by regulators as a form of mutation rather than 'genetic modification'. With such advances in biotechnology, the release of commercial varieties of major crops with new forms of nematode resistance, or new modes of delivery of control agents, is likely to become a commercial reality. To improve durability, transgenic traits could be based on resistance with different modes of action: for example, RNAi-based technology combined with expression of peptides which disrupt sensory activities. Ideally such traits would be added to existing crop genotypes with the best conventional or natural nematode resistance, to increase the effectiveness and durability of the nematode resistance trait. Biotech trait expression could also be limited to roots to minimise expression in harvested parts, and this could improve public acceptability. [ABSTRACT FROM AUTHOR]

Nematophagons fungus plays a key role; in the; area of nematode biological control, and has received increasing attention in recent years. Drechmeria coniospora is a typical obligate; ondoparasitic fungus, which specifically infects and parasites in its host nematodes. This study observed the entire process of D. coniospora infecting Caenorhabditis elegans by using high resolution scanning electron microscope (SEM). Thus, a direct and objective evidence was obtained for further studies on infection by D. coniospora and relevent genes involved in infection. The SEM images showed that D. coniospora recognized nematode by conidia, then adsorbed nematode's month cavity or vulva, and got into nematode. Conidia initially germinated and formed trophic hyphae inside the nematode. When trophic hyphae growth to certain extent, mycelia penetrated nematode cuticle, which led to the death of the host. Aerial mycelia produced new conidia. After these conidia were matured, another infection cycle began. The specific infection pattern and efficient infection ability of D. coniospora made it as a potential and superior strain for biological control against nematode. D. coniospora has a broad application prospect. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bacillus amyloliquefaciens ACB-08 and ACB-23 suppress soybean cyst nematode (SCN). • Bacillus spp. applied by seed treatment (ST) is better than in-furrow against SCN. • Bacillus spp. applied by ST is better than in-furrow to soybean growth-promotion. • Soybean growth-promotion is correlated to suppression of SCN by Bacillus spp. The soybean cyst nematode (SCN), Heterodera glycines Ichinohe, is a pest that is difficult to control worldwide and causes severe damage to soybeans. The demand for sustainable control strategies with Bacillus has increased; however, the use of Bacillus for SCN control is poorly studied compared to that of its use against other pests. We tested 19 isolates from three Bacillus spp. (B. subtilis, B. amyloliquefaciens, and B. methylotrophicus), which were assessed through inoculation in-furrow and via seed treatment (ST) to evaluate soybean growth promotion and SCN suppression. The effects of the Bacillus strains were compared with commercial biological and chemical agents (B. subtilis UFPEDA 764, abamectin, and cadusafos) and controls (with and without SCN infection). Plant height, fresh and dry shoot weight, pod number, chlorophyll index, total egg and second juvenile stage of SCN (J2s), J2s densities, and SCN reproductive factors were evaluated 70 days after sowing. Multivariate data were subjected to principal component analysis (PCA), which identified the optimal treatments for plant growth promotion and SCN suppression by suggesting correlations between them. The Bacillus treatments were not able to reduce initial nematode concentrations at reproductive factor levels <1.0; however, all treatments with Bacillus spp. reduced the final average nematode density by 76.72 % in ST and 66.15 % in-furrow compared to the untreated control (P < 0.01). The number of cysts in the soil was reduced by an of average 56.6 % in the ST and 35.33 % in-furrow. While in-furrow inoculation increased soybean germination, ST promoted greater plant growth. Bacillus amyloliquefaciens ACB-08 (4) and ACB-23 (30) were the most effective in promoting soybean growth and suppressing SCN. [ABSTRACT FROM AUTHOR]

Background: The aim of this work was to investigate the potential nematicidal activity of Annona crassiflora leaf extract against Caenorhabditis elegans. Methods: The hydroalcoholic leaf extract and its fractions (dichloromethane, ethyl acetate, methanol and water) were submitted to mobility assay against the roundworm Caenorhabditis elegans. GC-MS and NMR analysis were performed in order to identify metabolites. Results: The dichloromethane and ethyl acetate fractions showed to be the most active among the hydroalcoholic leaf extracts and its four fractions. The percentages of C. elegans larvae immobility were 98.13 and 89.66%, respectively, at a concentration of 1000 μg.mL-1. Besides some amino acids, palmitic acid methyl ester, 2-isopropyl-5-methylcyclohexanol, oleic acid methyl esther, stearic acid methyl ester, quercetin and kaempferol were also identified in these fractions. Conclusion: The results indicated that of A. crassiflora leaf ethanolic extract has a good potential as a source for natural nematicide. [ABSTRACT FROM AUTHOR]

Biofumigation is a sustainable method of soil management in cash crop rotations that can increase soil organic matter (SOM), moderate soil pH, suppress weeds and soilborne pathogens through glucosinolates (GSL), and increase water infiltration. This 2-year (2011-13) field study evaluated four different Brassica crops for their biofumigant potential in a chile pepper rotation system in southern New Mexico. The four cultivars included: three mustards (Brassica juncea 'Caliente 61', 'Caliente 199', and 'Pacific Gold') and one broccoli (Brassica oleracea var. botrytis 'Arcadia'). As a result of concerns that these mustards could be hosts for nematodes, a greenhouse study was conducted in the second year to evaluate the biofumigant crops for their southern root-knot nematode (Meloidogyne incognita, RKN) host suitability and their seedling establishment in the presence of RKN. In Year 1 (2011), conditions were ideal, which resulted in high mustard biomass production and, consequently, significantly higher SOM and lower pH than the bare soil control plots. However, there were no chile pepper yield differences among treatments. Conditions were much less favorable in Year 2 and the resultant poor biomass production did not cause an increase in SOM as seen in Year 1. In the RKN greenhouse study, broccoli was the least susceptible biofumigant crop. After one nematode generation (683 cumulative heat units), RKN populations were less than half of the original inoculum level on the broccoli. However, RKN populations increased in the presence of 'Caliente 61', 'Caliente 199', and 'Pacific Gold'. Overall, broccoli produced lower biomass and lower GSL concentrations than the mustard treatments but may be a valuable crop for growers with nematode issues because RKN populations decreased in its presence. Based on high biomass production and high GSL concentration, 'Caliente 199' showed the most potential as a biofumigant crop for southern New Mexico. [ABSTRACT FROM AUTHOR]

Anthelminthic resistance in nematodes of beef cattle is an emerging issue globally with implications for effective parasite control. The prevalence of resistance in beef cattle in the Mediterranean-style climatic zone of south-west Western Australia was assessed on 19 farms, using faecal egg count reduction tests. Pre-treatment faecal worm egg counts were compared with counts at 14 days after treatments with ivermectin (injectable), fenbendazole (oral), or levamisole (oral). A separately grazed group treated with topical ivermectin (pour-on) and sampled at 28 days was included as a comparison against injectable ivermectin. The results demonstrate that resistance is common, with failure of at least one anthelmintic (<95% reduction for each species, by arithmetic means) for either of the major species Cooperia oncophora or Ostertagia ostertagi on 17 of the 19 properties. Resistance to ivermectin (injectable) was demonstrated in C. oncophora in 59% of tests, but ivermectin was fully effective against O. ostertagi by this route. Conversely, O. ostertagi resistant to fenbendazole and levamisole were present on 50% and 67% of farms respectively, with both fully effective against C. oncophora . The finding of Haemonchus placei on several properties was unexpected but the egg counts were low and there is no suggestion of pathogenic effects. An indication of reduced efficacy of the pour-on ivermectin formulation compared to the injectable was apparent against both C. oncophora and O. ostertagi , and this may have implications for resistance development, given the widespread use of topical treatments reported in this region. This survey confirms that anthelminthic resistance in nematodes of beef cattle is common in Western Australia and the pattern of occurrence is in general agreement with surveys elsewhere in Australia and in other countries. [ABSTRACT FROM AUTHOR]

Parasitic diseases are a major constraint to optimum livestock production and are the major cause of economic loss in UK sheep flocks, with farmers remaining dependant on anthelmintics for control. In the UK, research and evidence based, “best practice” guidelines for sustainable control of parasites in sheep (SCOPS) were first produced in 2004 and have been regularly updated since. This study was designed to evaluate the effect of these best practice guidelines for worm control on lamb production and infection levels, compared with more traditional management. Sixteen farms were selected based on a 2 cube factorial design with 3 factors known to affect worm epidemiology: control regimen; farm type; and climatic region. A formalised plan for worm control using 7 potential resistance-delaying practices was prepared for each of the 8 best practice (SCOPS) farms, in conjunction with the farms veterinarians. The 8 farms in the traditional management group (CONTROL farms) were selected based on ongoing evidence of them using worm control strategies deemed to be “higher-risk”. A cohort of 40–50 study lambs at each farm was monitored from birth to finishing, allowing evaluation of lamb productivity, worm infection levels and for comparison of numbers of anthelmintic treatments. Birth and mid-season weights were used to calculate daily live-weight gain. Birth and finish dates were used to calculate time to finish and finish weights were also compared. Faecal egg counts, larval culture and species differentiation were undertaken throughout the year to assess the impact of the control strategies on worm burdens. There was no significant difference in results for any of the 3 production responses when comparing predicted means accounting for the differences in birth weight. In fact SCOPS farms had, on average, a higher daily weight gain and finish weight than CONTROL farms when comparing observed means. Statistical analysis of infection levels clearly showed no significant effect according to farm type ( p = 0.71) or treatment ( p = 0.81). In contrast the effect of region ( p = 0.08), although not significant, had a much larger effect size (standardised mean difference) with lower parasite burdens based on faecal egg counts on Northern farms compared to Southern farms. For both ewes and lambs, significantly fewer treatments were carried out on the SCOPS farms. The data collected from this study suggests that farms implementing SCOPS principles use less anthelmintic than other farms, without loss of animal performance or increased worm burden. [ABSTRACT FROM AUTHOR]

The effect of aqueous extracts of Nigella sativa, Ferula assa-foetidae, Peganum harmala, and Portulaca oleracea, separately and in combination with salicylic acid (SA), β-aminobutyric acid (BABA), and jasmonic acid (JA) were examined for the control of M. javanica in the laboratory and greenhouse. Eggs and second-stage juveniles were exposed to different concentrations of the plant extracts and defense inducer (DI) molecules. In the greenhouse, the effect of treatments on the number of juveniles in roots, nematode reproduction, and plant growth were evaluated. The highest mortality of juveniles and lowest egg hatch occurred after exposure simultaneously to F. assa-foetida extract and BABA for 72 hr. Concomitant application of F. assa-foetida extract with 1.5 mM concentration of all DI molecules inhibited penetration of juveniles into roots as effectively as cadusafos which was used as a standard nematicide. Concurrent application of 1.5 mM BABA or SA with all of the plant extracts lowered nematode reproduction similar to the nematicide standard. Application of plant extracts and DI molecules did not affect fresh or dry shoot weight, but did affect shoot height and root fresh weight. Based on our data, the defence inducer molecules, in combination with all of the plant extracts that were tested, have potential for the control of M. javanica. [ABSTRACT FROM AUTHOR]

A survey for the rat lungworm, Angiostrongylus cantonensis, a nematode parasite of rats and potentially injurious to humans, was conducted in Florida in 2011-2013 in concomitance with an eradication program of the giant African snail, Lissachatina fulica, an invasive snail recently found in southern Florida. Twenty-four percent of the giant African snail samples examined were infested by the coiled second- and infective third-stage juveniles of the nematode. These life stages embedded in or dislodged from comminuted snail tissue in water were detected using both molecular quantitative real-time polymerase chain reaction and morphological analyses. Nematode recovery from snail tissues was greater when both methods were concomitantly used on tissue samples from the same giant African snail specimen. More rat lungworms were extracted from the mantel than from the foot tissues of nematode-infested snails. The results of these analyses were validated by the Centers for Disease Control and Prevention in Atlanta, GA. To our knowledge, this is the first identification of the juveniles of A. cantonensis infecting L. fulica made in Florida using integrated morphological and molecular analyses. [ABSTRACT FROM AUTHOR]

Sheep nematode control utilising refugia-based strategies have been shown to delay anthelmintic resistance, but the optimal indices to select individuals to be left untreated under extensive sheep grazing conditions are not clear. This experiment tested the hypothesis that high body condition can indicate ability of mature sheep to better cope with worms and therefore remain untreated in a targeted treatment programme. Adult Merino ewes from flocks on two private farms located in south-west Western Australia (Farm A, n = 271, and Farm B, n = 258) were measured for body condition score (BCS), body weight and worm egg counts (WEC) on four occasions between May and December (pre-lambing, lamb marking, lamb weaning and post-weaning). Half of the ewes in each flock received anthelmintic treatments to suppress WEC over the experimental period and half remained untreated (unless critical limits were reached). Response to treatment was analysed in terms of BCS change and percentage live weight change. No effect of high or low initial WEC groups was shown for BCS response, and liveweight responses were inconsistent. A relatively greater BCS response to treatment was observed in ewes in low BCS pre-lambing compared to better-conditioned ewes on one farm where nutrition was sub-optimal and worm burdens were high. Sheep in low body condition pre-lambing were more than three times more likely to fall into a critically low BCS (<2.0) if left untreated. Recommendations can be made to treat ewes in lower BCS and leave a proportion of the higher body condition sheep untreated in a targeted selective treatment programme, to provide a population of non-resistant worms to delay the development of resistance. [ABSTRACT FROM AUTHOR]

We describe a case of anthelmintic resistance on one of the largest organic small ruminant farms in Denmark. The flock was established in 2007 by purchase of animals from other Danish farms and had history of clinical parasitism, high mortality of young stock and anthelmintic treatment failure. In October 2011, 40 lambs and 40 kids were selected for a faecal egg count reduction test (FECRT) with fenbendazole (FBZ), ivermectin (IVM), moxidectin (MOX) and levamisole (LEV). Lambs were treated with the recommended sheep dose of each product while kids received the sheep dose of IVM, 1.5× sheep dose of MOX and 2× sheep dose of FBZ and LEV. Untreated lambs and kids were also included and three methods for calculating faecal egg count (FEC) reduction were compared. In a subsequent investigation, a controlled efficacy test (CET) with FBZ and IVM was performed in lambs infected with Haemonchus contortus and Trichostrongylus colubriformis isolated from adult goats on the farm. Recovered specimens of H. contortus were subjected to pyrosequencing for detection of single nucleotide polymorphisms (SNPs) related to benzimidazole (BZ) resistance. During the FECRT, FECs in untreated lambs dropped significantly by 47%. No FEC reduction was detected in untreated kids. After FBZ treatments, FEC reductions in lambs and kids ranged from 15 to 54% and 49–56%, respectively, according to the different calculation methods. Post IVM treatments, FEC reductions in lambs and kids varied between 71–90% and 81–83%, correspondingly. LEV and MOX reduced FECs by 98–100% in both species. In the CET, FBZ reduced H. contortus worm counts by 52–56% and no reduction in T. colubriformis counts were detected after treatment. IVM eliminated 100% of H. contortus and reduced T. colubriformis counts by 84–92%, according to different calculation methods. Pyrosequencing of isolated H. contortus revealed increased frequencies of the BZ resistance-related SNP in codon 200 of the β-tubulin isotype 1 gene. Frequency of BZ resistance-related SNPs in codons 167 and 198 were very low and did not exceed levels as obtained in the susceptible reference isolate. Anthelmintic resistance was confirmed in this recently established organic farm and low field efficacy of FBZ was verified by CET and pyrosequencing. BZ-resistant populations of H. contortus and T. colubriformis were isolated for the first time in Denmark. Problems with correct dosing of goats, the observed FEC reduction in untreated lambs and the relevance of including a control group in the FECRT are discussed. [ABSTRACT FROM AUTHOR]

Objective This study aimed to provide an indication of the prevalence and severity of anthelmintic resistance (AR) in the Australian sheep industry by compiling the results of faecal worm egg count reduction tests (FECRTs). Methods Government and private parasitology laboratories, pharmaceutical companies and veterinarians known to have conducted FECRTs were asked to provide results that conformed to Australian and New Zealand standard diagnostic procedures. Results Data were available from a total of 390 tests, with larval differentiation conducted in 222 cases. Pooled results from all states for the macrocyclic lactone (ML) class showed a lower prevalence of AR against combined species for moxidectin (54%) compared with abamectin (77%) and ivermectin (87%). Analysis by state revealed higher levels of ML-resistant Teladorsagia sp. in Tasmania and Western Australia than in other states and ML-resistant Haemonchus sp. was more frequently detected in New South Wales. Conclusion This compilation of results of FECRTs conducted by Australian parasitology laboratories in 2009-12 showed widespread AR of the common sheep nematodes ( Teladorsagia, Trichostrongylus and Haemonchus) to all broad-spectrum anthelmintics, with the exception of monepantel, whether used singly or in combination. [ABSTRACT FROM AUTHOR]

Background: Plant-parasitic nematodes developed strategies to invade and colonize their host plants, including expression of immune suppressors to overcome host defenses. Meloidogyne graminicola and M. incognita are root-knot nematode (RKN) species reported to damage rice ( Oryza sativa L.) cultivated in upland and irrigated systems. Despite M. incognita wide host range, study of the molecular plant - RKN interaction has been so far limited to a few dicotyledonous model plants. The aim of this study was to investigate if the rice cv. Nipponbare widely used in rice genomic studies could be used as a suitable monocotyledon host plant for studying M. incognita pathogenicity mechanisms. Here we compared the ability of M. graminicola and M. incognita to develop and reproduce in Nipponbare roots. Next, we tested if RKNs modulates rice immunity-related genes expression in galls during infection and express the Mi-crt gene encoding an immune suppressor. Results: Root galling, mature females, eggs and newly formed J2s nematodes were obtained for both species in rice cultivated in hydroponic culture system after 4-5 weeks. Meloidogyne graminicola reproduced at higher rates than M. incognita on Nipponbare and the timing of infection was shorter. In contrast, the infection characteristics compared by histological analysis were similar for both nematode species. Giant cells formed from 2 days after infection (DAI) with M. graminicola and from 6 DAI with M. incognita. Real-time PCR (qRT-PCR) data indicated that RKNs are able to suppress transcription of immune regulators genes, such as OsEDS1, OsPAD4 and OsWRKY13 in young galls. Four M. incognita reference genes ( Mi-eif-3, Mi-GDP-2, Mi-Y45F10D.4, and Mi-actin) were selected for normalizing nematode gene expression studies in planta and in pre-parasitic J2s. Meloidogyne incognita expressed the immune suppressor calreticulin gene ( Mi-crt) in rice roots all along its infection cycle. Conclusion: RKNs repress the transcription of key immune regulators in rice, likely in order to lower basal defence in newly-formed galls. The calreticulin Mi-CRT can be one of the immune-modulator effectors secreted by M. incognita in rice root tissues. Together, these data show that rice is a well suited model system to study host- M. incognita molecular interactions in monocotyledons. [ABSTRACT FROM AUTHOR]

The success of plant-parasitic nematodes as competitors with humans for crops is evidenced by the parasites' significant and continuous economic drain on global agriculture. Scientific efforts dedicated to the control of plant-parasitic nematodes employ strategies from the environmental to molecular levels. Understanding the interaction of the nematode with its environment, and the molecules involved, offers great promise for novel control agent development. Perhaps more significantly, such knowledge facilitates the generation of ever more detailed and sophisticated information on nematode biology and new molecular targets. Among the most economically important groups of plant-parasitic nematodes are those comprising the cyst-forming species and the root-knot nematodes. Presented here is a brief overview of research into the biology of these parasites relative to their life cycles. Recent advances in elucidating the molecular biology and biochemistry of nematode-plant interactions during the internal parasitic stages of the life cycle have been driven by advances in genomics and transcriptomics. The remarkable discoveries regarding parasitism, and the application of genetic resources in these findings, provide a template for advanced investigation of external, survival stages biology. While survival biology research lags somewhat behind that of parasitism with regard to the molecular genetics of signalling and response, its extensive catalogue promises explosive rates of discovery as progress in genomics and transcriptomics allows a molecular genetic examination of embryogenesis, dormancy and hatching. Our group is interested in behaviour, development and hatching of cyst and root-knot nematodes, and the effects of the environment on the mechanisms of these activities. Phytochemical and temperature effects are discussed, and evidence is presented that the cyst may provide useful molecules for exploring nematode physiology. [ABSTRACT FROM AUTHOR]

Objective To establish the prevalence of anthelmintic resistance in ovine gastrointestinal nematodes in southern Queensland. Design An observational parasitological study using the faecal egg count reduction test. Methods Sheep farms (n = 20) enrolled in this study met the twin criteria of using worm testing for drench decisions and having concerns about anthelmintic efficacy. On each farm, 105 sheep were randomly allocated to one of six treatment groups or an untreated control group. Faecal samples were collected on day 0 and days 10-14 for worm egg counts and larval differentiation. Single- and multi-combination anthelmintics, persistent and non-persistent, oral liquid or capsule, pour-on and injectable formulations were tested. Monepantel was not tested. Farmers also responded to a questionnaire on drenching practices. Results Haemonchus contortus was the predominant species. Efficacy <95% was recorded on 85% of farms for one or more anthelmintics and on 10% of farms for six anthelmintics. No resistance was identified on three farms. The 4-way combination product was efficacious (n = 4 farms). Napthalophos resistance was detected on one farm only. Resistance to levamisole (42% of farms), moxidectin injection (50% of farms) and the closantel/abamectin combination (67% of farms) was identified. Moxidectin oral was efficacious against Trichostrongylus colubriformis, which was predominant on only one farm. Of the farms tested, 55% ran meat breeds, 60% dosed more than the recommended dose rate and 70% always, mostly or when possible practised a 'drench and move' strategy. Conclusion This level of anthelmintic resistance in southern Queensland will severely compromise worm control and force increased use of monepantel. [ABSTRACT FROM AUTHOR]

The purple pigment violacein is well known for its numerous biological activities including antibacterial, antiviral, antiprotozoan, and antitumor effects. In the current study we identify violacein as the antinematode agent produced by the marine bacterium Microbulbifer sp. D250, thereby extending the target range of this small molecule. Heterologous expression of the violacein biosynthetic pathway in E. coli and experiments using pure violacein demonstrated that this secondary metabolite facilitates bacterial accumulation in the nematode intestine, which is accompanied by tissue damage and apoptosis. Nematodes such as Caenorhabditis elegans utilise a well-defined innate immune system to defend against pathogens. Using C. elegans as a model we demonstrate the DAF-2/DAF-16 insulin/IGF-1 signalling (IIS) component of the innate immune pathway modulates sensitivity to violacein-mediated killing. Further analysis shows that resistance to violacein can occur due to a loss of DAF-2 function and/or an increased function of DAF-16 controlled genes involved in antimicrobial production (spp-1) and detoxification (sod-3). These data suggest that violacein is a novel candidate antinematode agent and that the IIS pathway is also involved in the defence against metabolites from non-pathogenic bacteria. [ABSTRACT FROM AUTHOR]

Background: gastrointestinal parasitism is an important limitation for sheep production in Cuba. This situation is worsened by the lack of an effective parasite control strategy. Objective: to assess whether selective and strategic treatments could help achieve a level of control of nematodes similar to systematic drenchings. Methods: an experimental group of 73 Pelibuey ewes was divided into four groups: 1) the Epizoo group (Epizootiological drenching schedule) was dewormed at lambing in the middle of the dry season and at weaning; 2) the FAMACHA© group was treated according to the color of ocular mucosa as indicative of anemia (Categories 4 and 5 of the FAMACHA© color chart); 3) the Chemical group was drenched every three months; and 4) the control group, in which animals remained untreated unless fecal egg count (FEC) was higher than 1500 eggs per gram of feces or the packed cell volume (PCV) was lower than 15%. FECs, body scorings (BCS), hematocrits and color of ocular mucosa (COM) were evaluated monthly. Results: the control group showed the highest FEC and the lowest PCV. We also observed similar levels of FEC and body condition (BCS) in the Epizoo, FAMACHA© and Chemical groups. The PCV in FAMACHA© group was the highest, while no differences were found between the other two groups. Hematocrit had a strong negative correlation (-0.41) with FEC. The FAMACHA© method allowed a dramatic decrease in anthelmintic use. Conclusions: the obtained results suggest that FAMACHA© method could be incorporated as part of an effective parasite control strategy in sheep. [ABSTRACT FROM AUTHOR]

Ostertagia ostertagi is the most important gastro-intestinal nematode affecting cattle in the UK. It has the potential to cause disease (ostertagiosis) in young grazing animals, usually in the second half of the year (type 1 disease) and also to inhibit its development in the host and cause disease in late winter/early spring (type 2 disease). Type 2 disease may have a low morbidity but is more severe than type 1 disease, possibly due to the mass synchronous emergence of inhibited parasites causing severe abomasal damage and also possibly due to failure to diagnose and treat quickly. This parasite continues to interest researchers due to the overwhelming evidence of it causing significant economic loss in cattle. [ABSTRACT FROM AUTHOR]

Sugarcane is the main industrial crop in Kjtadaito Island (Okinawa), Japan, and the objective of this study was to estimate potential damage to sugarcane by plant-parasitic nematodes (PPN). We selected 15 sugarcane fields with the same cultivar and cropping type in Kitadaito Island. Various kinds of PPN were found in all the fields and the proportion of PPN to the total nematode number was ca 50%, which is relatively high compared to other Japanese upland fields. Lesion (Pratylenchus sp.), stunt (Tylenchorhynchus sp.) and spiral (Helicotylenchus sp.) nematodes were detected at mean densities of 48, 22 and 6 (20 g soil)-1, respectively, from all the fields, and lance (Hoplolaimus sp.) and ring nematodes from half of the fields. The results suggested that sugarcane fields in Kitadaito Island were ubiquitously infested with a variety of PPN with a relatively high abundance. One of the fields was studied further to examine the potential relationship between PPN and sugarcane plant growth. Since no nematicide is registered for sugarcane fields in Japan, an appropriate agrochemical was selected by testing its efficacy against PPN before evaluating the relationship between a PPN community and sugarcane growth. The results of a 10-week pot experiment for sugarcane growth showed that the number of PPN decreased by applying a nematicide fosthiazate, and that sugarcane seedling biomass was significantly greater by 34-63% in soils with applied nematicide than in non-applied control soils, suggesting that PPN may suppress sugarcane growth in Kitadaito Island. [ABSTRACT FROM AUTHOR]

Highlights: [•] Novel technique for plant volatile organic compounds (VOCs) test. [•] Exposed water to plant VOCs lead it to acquire molecules. [•] Plant VOC damage to Meloidogyne incognita J2 affect nematode pathogenicity and growth. [•] Analyses by GC/MS revealed molecules, once soluble in water, may affect nematodes. [•] Retaintion of VOCs in water avoids them from escaping to the air. [Copyright &y& Elsevier]

In many countries the presence of anthelmintic resistance in nematodes of small ruminants, and in some cases also in those infecting cattle and horses, has become the status quo rather than the exception. It is clear that consideration of anthelmintic resistance, and its management, should be an integral component of anthelmintic use regardless of country or host species. Many years of research into understanding the development and management of anthelmintic resistance in nematodes of small ruminants has resulted in an array of strategies for minimising selection for resistance and for dealing with it once it has developed. Importantly, many of these strategies are now supported by empirical science and some have been assessed and evaluated on commercial farms. In sheep the cost of resistance has been measured at about 10% of the value of the lamb at sale which means that losses due to undetected resistance far outweigh the cost of testing anthelmintic efficacy. Despite this many farmers still do not test for anthelmintic resistance on their farm. Many resistance management strategies have been developed and some of these have been tailored for specific environments and/or nematode species. However, in general, most strategies can be categorised as either; identify and mitigate high risk management practices, maintain an anthelmintic-susceptible population in refugia, choose the optimal anthelmintic (combinations and formulations), or prevent the introduction of resistant nematodes. Experiences with sheep farmers in both New Zealand and Australia indicate that acceptance and implementation of resistance management practices is relatively easy as long as the need to do so is clear and the recommended practices meet the farmer's criteria for practicality. A major difference between Australasia and many other countries is the availability and widespread acceptance of combination anthelmintics as a resistance management tool. The current situation in cattle and horses in many countries indicates a failure to learn the lessons from resistance development in small ruminants. The cattle and equine industries have, until quite recently, remained generally oblivious to the issue of anthelmintic resistance and the need to take pre-emptive action. In Australasia, as in other countries, a perception was held that resistance in cattle parasites would develop very slowly, if it developed at all. Such preconceptions are clearly incorrect and the challenge ahead for the cattle and equine industries will be to maximise the advantages for resistance management from the extensive body of research and experience gained in small ruminants. [ABSTRACT FROM AUTHOR]

A new polyprenylated benzophenone, named epunctanone ( 1), was isolated from the stem bark of Garcinia epunctata Stapf, together with eight known compounds, 7-epiisogarcinol ( 2), 2,6-dimethoxy- p-benzoquinone ( 3), friedelin ( 4), lupeol ( 5), 16 β-hydroxylupeol ( 6), betulin ( 7), stigmasterol ( 8), and rheediaxanthone A ( 9). The structure of epunctanone ( 1) was established by detailed analysis of its spectroscopic data, especially 1D- and 2D-NMR, and HR-MS data. All these compounds were evaluated for their antimicrobial and anti-protozoan activities. They were also assayed to determine if any of the compounds were nonpeptide agonist ligands for nematodal G-protein-coupled receptors, which would be an indication of potential antinematodal activity. Among the isolated compounds, 7-epiisogarcinol ( 2) was the most active against Candida albicans. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the liveweight gain of lambs, infected by multidrug-resistant nematodes, treated by conventional schemes of helminth control or using a schedule based on fecal egg count reduction test (FECRT). The flock was selected after a FECRT (experiment 1) which revealed a parasite population resistant to benzimidazoles, imidazothiazoles, macrocyclic lactones (ivermectin), salicylanilides, nitrophenols, and organophosphates. Despite the parasite resistance to ivermectin (an avermectin), the moxidectin (a milbemycin) was effective against the gastrointestinal nematodes (PR > 90 %). In experiment 2, 48 suckling lambs were distributed in four randomized blocks (G1, G2, G3, and G4) by previous body weighings. G1 was kept as untreated control; G2 was treated following a FECRT-based schedule with drugs chosen based on fecal analysis (first drench with moxidectin, second drench with a combination of moxidectin and levamisole, and third drench with praziquantel, an anti-cestode drug); G3 and G4 received three drenches with ivermectin or disophenol, respectively. Body weighings and fecal analysis of these lambs were performed every 2 weeks over a 98-day period. An effective control of gastrointestinal nematodes was obtained with two nematicidal drenches following the FECRT-based schedule of treatments. On the other hand, eggs per gram of feces (EPG) counts were no different among untreated control, G3, and G4. Lambs treated using the FECRT-based schedule had the greatest liveweight gain among the groups tested. Additionally, liveweight gain was no different among the groups G3, G4, and G1. The FECRT-based schedule of anthelmintic treatments was beneficial regarding productivity and sustainability of helminth control in lambs infected by multidrug-resistant nematodes. [ABSTRACT FROM AUTHOR]

Abstract: Gastrointestinal nematode parasites in small ruminants pose a major challenge to global agriculture. In most cases, their control depends on the availability of anthelmintics, which must be used in a manner that achieves a balance between ensuring adequate productivity and minimising the impact of inevitable selection for drug resistance. In this observational field study, the liveweight gains of lambs grazed on putative heavily infective larval contaminated pasture were compared after effective or ineffective anthelmintic drug treatments. Moxidectin, monepantel, and a derquantel–abamectin combination achieved 100% post treatment efficacies in faecal egg count reduction tests, while the efficacy of levamisole against Teladorsagia circumcincta was only 33%. During the 14 days after treatment, lambs treated with moxidectin, monepantel, and a derquantel–abamectin combination, gained about 0.3kg, 0.5kg, and 0.7kg, respectively, more than those treated with levamisole, generally supporting the economic investment in use of effective drugs. These observations serve to highlight the manner in which effective anthelmintic drugs are used most efficiently with the primary objective of minimising subsequent exposure of naïve lambs to high levels of infective larval challenge, as opposed to the more common practice of simply treating animals grazing on heavily contaminated pastures. [Copyright &y& Elsevier]

Bacillus thuringiensis has been widely used as a biopesticide, primarily for the control of insect pests, but some B. thuringiensis strains specifically target nematodes. However, nematicidal virulence factors of B. thuringiensis are poorly investigated. Here, we describe virulence factors of nematicidal B. thuringiensis DB27 using Caenorhabditis elegans as a model. We show that B. thuringiensis DB27 kills a number of free-living and animal-parasitic nematodes via intestinal damage. Its virulence factors are plasmid-encoded Cry protoxins, since plasmid-cured derivatives do not produce Cry proteins and are not toxic to nematodes. Whole-genome sequencing of B. thuringiensis DB27 revealed multiple potential nematicidal factors, including several Cry-like proteins encoded by different plasmids. Two of these proteins appear to be novel and show high similarity to Cry21Ba1. Named Cry21Fa1 and Cry21Ha1, they were expressed in Escherichia coli and fed to C. elegans, resulting in intoxication, intestinal damage, and death of nematodes. Interestingly, the effects of the two protoxins on C. elegans are synergistic (synergism factor, 1.8 to 2.5). Using purified proteins, we determined the 50% lethal concentrations (LC50s) for Cry21Fa1 and Cry21Ha1 to be 13.6 μg/ml and 23.9 μg/ml, respectively, which are comparable to the LC50 of nematicidal Cry5B. Finally, we found that signaling pathways which protect C. elegans against Cry5B toxin are also required for protection against Cry21Fa1. Thus, B. thuringiensis DB27 produces novel nematicidal protoxins Cry21Fa1 and Cry21Ha1 with synergistic action, which highlights the importance of naturally isolated strains as a source of novel toxins. [ABSTRACT FROM AUTHOR]

Auxarthron reticulatum DY-2 was isolated from field soils in Jeonnam Province, South Korea, and its culture filtrate was active as a bionematicide agent against the pine wood nematode Bursaphelenchus mucronatas. The nematicidal activity against B. mucronatus was proportional to the concentration of the culture filtrate. The nematicidal compounds, dimethyl fumarate and bis(2-ethylhexyl)phthalate, were isolated and identified from A. reticulatum DY-2 culture filtrate using silica gel column chromatography combined with high performance liquid chromatography and gas chromatography-mass spectrometry. The bioassays on nematicidal activity revealed that bis(2-ethylhexyl)phthalate and dimethyl fumarate at 1% concentration resulted in 70 and 100% mortality of B. mucronatus, respectively, after 48 h exposure. This is the first report that these two compounds exhibit a property of nematicidal activity, especially on Bursaphelenchus spp. [ABSTRACT FROM AUTHOR]

It was hypothesized that chickens with extremely varying body weights (BW) from an otherwise homogeneous host sample cope differently with Ascaridia galli (Schrank 1788) infection. Small and large birds, falling into either the lower or the upper 5 % quantiles of BW distribution of a parent stock flock, were selected at an age of 4 weeks, housed separately and fed restrictively with the same amount of feed. At week 5, all the small and large birds (635 and 1,297 g/bird, respectively; P < 0.001) were inoculated with 1,000 A. galli eggs and euthanized 52 days post-infection. Small birds had higher daily weight gains ( P = 0.004) but final BWs of larger birds were still higher ( P < 0.001) at slaughter. Prevalence, intensity of infection as well as worm abundance were higher in small birds when compared with the large birds ( P < 0.05), whereas plasma concentrations of A. galli-specific antibodies and worm length remained unaffected ( P > 0.05). In conclusion, large birds resist A. galli infection more effectively than do small ones, possibly through different mechanisms acting on allocation of available nutrient and body reserves under the exposure of the infection. [ABSTRACT FROM AUTHOR]

Under greenhouse conditions, three insect growth regulators, buprofezin, flufenoxuron and pyriproxyfen, at field concentrations and other two lower concentrations were evaluated for controlling of root knot nematode,Meloidogyne incognita, infecting eggplant (Solanum melongenaL.) cv. Baladi. Generally, the tested pesticides reduced the number of galls, egg masses, females and developmental stages in roots and juveniles in soil compared to untreated check. The percentages of reduction were positively proportional with the respective concentrations. Flufenoxuron at its highest concentration was the most effective pesticide in reducing galls, egg masses, females and developmental stages compared with pyriproxyfen and buprofezin. The percentages of reduction caused by flufenoxuron were 67.80, 69.57, 70.75 and 95.23% for the, respective nematode criteria, while buprofezin at the highest concentration was the most effective in reducing number of hatched juveniles in soil followed by flufenoxuron and pyriproxyfen. Data showed that the length and fresh and dry weights of root and shoot of egg plant were increased with the lowest concentrations than the highest ones. [ABSTRACT FROM PUBLISHER]

Abstract: The objective of this study was to determine the impact of integrated parasite management (IPM) training, including FAMACHA© eyelid color scoring, on the ability of U.S. sheep and goat producers to control gastrointestinal nematodes (GIN) on their farms. A survey was developed and provided to over 2000 producers trained from 2004 to 2008 in IPM with questions involving farm size (number of sheep/goats), location (U.S. state), impact of training on parasite control efforts and parasite problems on farm, and IPM practices used. Responses were divided into U.S. Census regions of the U.S. Descriptive statistics and logistic regression were used to describe results. Most of the 729 respondents were from the southern region of the U.S. (54.3%) and were small-scale producers (50 or less animals; 64.8%). Nearly all of the respondents (95.1%) agreed that IPM workshop attendance made a difference in their ability to control and monitor parasitism in their herd or flock and employed IPM practices to control GIN (96.3%). The most popular practices respondents used were rotational grazing (71.2%), genetic selection (choosing a parasite resistant breed and/or culling susceptible animals; 52.7%), grain supplementation on pasture to improve nutrition (44.0%), and increased height of plants being grazed (41.8%). Although reporting using a practice decreased (P <0.05) the likelihood of reporting fewer problems, for each 1-point increase in the number of practices which producers employed to control internal parasitism in their herd or flock, they were 16% more likely to report fewer GIN problems (P <0.05). Approximately 75% of respondents indicated an economic benefit of IPM on their farm (P <0.05), and those reporting savings of over $80 were more likely to report fewer problems (P <0.05) with parasites after the training while those reporting no economic benefit were less likely to report fewer problems with GIN (P <0.001). Overall, IPM training resulted in positive impacts for producers responding to the survey and should continue. [Copyright &y& Elsevier]

In this article, the author reflects on a research paper "Host cell responses to endoparasitic nematode attack: structure and function of giant cells and syncytia" by Jones M.J.K. that was published in a 1981 issue of the periodical "Annals of Applied Biology." Topics discussed include nematode-induced feeding sites, plant-parasitic nematodes including root-knot and cyst nematodes and host–parasite interaction of sedentary endoparasitic nematodes.

The nematicidal action of three seed mill wastes from cress (Eruca sativaMill.), castor (Ricinus communisL.) and linseed (Linum usitatissimumL.) as soil additives were tested at three rates (on base lower rate, recommended rate and higher rate), under field conditions at the research and production station of the National Research Centre, El-Nubaria district, El-Beheira governorate, Western Nile Delta region, Egypt, to study the physiological influence of these substances on potato yield, their role againstMeloidogyne arenariainfection and the alkaloidal content. All the evaluated treatments significantly (p ⩽ 0.05 and/or 0.01) reduced the numbers of juveniles in soil and in roots, number of galls, egg masses, gall and egg mass indices and consequently rate of nematode build-up as compared to untreated plants(control). Statistical differences in the nematode stages were found within and between treatments. The percentage of reduction in the nematode stages was comparatively more with using of Linseed mill wastes followed by castor seed mill wastes, then cress seed mill wastes. Regarding to the potato yield, all the evaluated amendments achieved significantly (p ⩽ 0.05 and/or 0.01) increased, total contents of alkaloidal content as compared to untreated plants. On the other hand, all the evaluated amendments achieved significantly (p ⩽ 0.05 and/or 0.01) decreased the solanine values as compared to untreated plants. These results indicate that some natural compounds may be used as natural nematicides in controllingM. arenarianematode and improving the quality and yield of potato plants. [ABSTRACT FROM AUTHOR]

The effect and the potential application of stinging nettle exudates in controlling plant nematodes were investigated. The effect of root exudates of the stinging nettle interplanted with tomato and bean and its potential application as green manure for reducing the population of plant nematodes were also investigated. The results showed that the counts of the nematodes in the base of stinging nettle were significantly lower than those in the 2 m radius from the plant. Comparison of mean counts of the nematodes showed a differential controlling effect of stinging nettle exudates on the nematodes. The counts of the nematodes in pots pre-sown with stinging nettle were reduced, while in pots planted with tomato plants the reductions were significantly lower. The application of stinging nettle as green manure in nematode-infected pots planted with tomato/bean caused significant reductions in the counts of the nematodes. [ABSTRACT FROM AUTHOR]

Dimethyl disulfide (DMDS) is a soil fumigant used in agricultural systems as an alternative to methyl bromide (MeBr) for the control of soilborne pests and pathogens. However, fumigants including DMDS that have broad biocidal activity can affect both target and non-target organisms in soil. This study focused on the effects of DMDS on the recovery of ecologically important microbial communities and soil abiotic factors while affecting plant parasitic nematodes in both field and microplot trials. Phospholipid fatty acid (PLFA) analysis was used to characterize changes in microbial community structure over time. Total amount of PLFA as well as all major non-target soil microbial groups such as Gram positive bacteria, Gram negative bacteria, fungi, arbuscular mycorrhizal fungi (AMF), and actinomycetes decreased significantly 15 d after fumigation in the untreated control as well as in all the rates of DMDS tested in a microplot trial. Fumigation had little effect on microbial biomass but at some time points some treatments did affect microbial community structure. Canonical multivariate analysis of variance indicated that soil microbial communities 45, 60, and 90 d after fumigation were similar to one another compared with 15 d after fumigation. The research showed that reduction and changes in microbial community biomass and structure were mainly due to environmental factors and therefore, it is concluded that DMDS fumigation did not impact the activity of beneficial microorganisms. Total N, C, and other abiotic factors were also not affected by DMDS fumigation. Plant parasitic nematodes were greatly affected by DMDS fumigation and this interaction could be related to its mode of action which affects nematode mitochondrial activity. [ABSTRACT FROM AUTHOR]

Equine gastrointestinal nematodes are ubiquitous; in horses that graze contaminated pasture and that are not treated appropriately, large numbers of worms can accumulate, which can lead to serious clinical disease. Nematode control has traditionally followed interval treatment regimens, which involve regular anthelmintic administration to all horses based on the strongyle egg reappearance periods of each drug, usually defined around the time of licensing. Interval treatment programmes have resulted in substantial reductions in large strongyle disease, but have made major contributions to the development of anthelmintic resistance, particularly in cyathostomins. Cyathostomin resistance to 2 of the 3 available anthelmintic classes is widespread, and resistance to both classes in single populations is not uncommon. Reduced efficacy of the most commonly used macrocyclic lactone anthelmintics, as measured by shortened egg reappearance periods after treatment, is emerging in cyathostomins. Macrocyclic lactone resistance is also now commonly reported in Parascaris equorum on stud farms. Faecal worm egg counts ( FWEC) are increasingly being used as part of targeted approaches to parasite control, whereby only those horses with moderate to high FWEC within a group are treated with an anthelmintic. The objective of this approach is to reduce environmental contamination, while leaving a proportion of the worm population in some horses unexposed to selection pressure for anthelmintic resistance. This article reviews recent findings in equine parasitology research that will underpin guidelines for control, with a particular focus on how to optimise the value of FWEC methodologies and anthelmintic efficacy analyses. [ABSTRACT FROM AUTHOR]

Soil fumigation continues to play an important role in soil disinfection, but tools to significantly reduce emissions while providing environmental benefits (e.g., biochar) are lacking. The objective of this study was to determine the effects of biochar products on fumigant 1,3-dichloropropene (1,3-D) and chloropicrin (CP) emissions, their distribution and persistence in soil, nematode control, and potential toxicity to plants in a field trial. Treatments included three biochar products [two derived from almond shells (ASB) at either 550 or 900 °C pyrolysis temperature and one from coconut shells (CSB) at 550 °C] at 30 and 60 t ha−1, a surface covering with a low permeability film (TIF), and no surface covering (control). A mixture of 1,3-D (∼65%) and CP (∼35%) was injected to ∼60 cm soil depth at a combined rate of 640 kg ha−1. All biochar treatments significantly reduced emissions by 38–100% compared to the control. The ASB (900 °C) at both rates reduced emissions as effectively as the TIF (by 99–100%). Both fumigant emission reduction and residue in surface soil were positively correlated with biochar's adsorption capacity while cucumber germination rate and dry biomass were negatively correlated with residual fumigant concentrations in surface soil. This research demonstrated the potential and benefits of using biochar produced from local orchard feedstocks to control fumigant emissions. Additional research is needed to maximize the benefits of biochar on fumigant emission reductions without impacting plant growth. [Display omitted] • Biochar reduced 1,3-dichloropropene and chloropicrin emissions by 38–100%. • Biochar did not compromise efficacy of fumigants on Citrus nematode. • Almond shell biochar enhanced seed germination due to its nutrients. • Coconut shell biochar retained high fumigant residue and exhibited phytotoxicity. [ABSTRACT FROM AUTHOR]

Nematicidal and hatching inhibition activities (HIA) of the methanol extracts from Dryobalanops aromatica (DA) and Mentha haplocalyx var. piperascens (MH), their constituents, and emulsified concentrate and granule formulations containing the methanol extracts as active ingredients, were compared with those of commercial nematicides, cadusafos and fosthiazate, against Meloidogyne incognita second-stage juveniles (J2) and eggs using well plate, container and pot assays. In a well plate assay with J2, DA applied at 500, 250 and 125 ppm resulted in 100, 95 and 55% mortality, respectively, while MH showed 80% mortality even at the lower concentration of 63 ppm. MH gave stronger HIA than DA at 1000 and 500 ppm. In addition, α-pinene, camphor, borneol and p-menthole, which are the main components of DA and MH extracts, showed strong nematicidal properties and HIA. In particular, the nematicidal activity of p-menthole among them was the highest and its HIA was also stronger than that of cadusafos and fosthiazate. In a container test using emulsifiable concentrate (EC) and granule (G) formulations containing 50 and 30% DA and MH, respectively, EC of D. aromatica showed a stronger LC50 value (0.203 μl (g soil)-1) than G formulation (0.935 mg (g soil)-1). However, their effects were fewer than MH formulations. The lethality of EC and G formulations containing MH was comparable to that of fosthiazate soluble concentrate and granule formulations. In another test using pots containing soils naturally infected by M. incognita, these plant formulations significantly inhibited the nematode-population density judging from the number of galls that formed on tested tomato roots after 8 weeks. These results suggest that DA and MH methanol extracts, as well as their constituents, might be useful as management agents against M. incognita. [ABSTRACT FROM AUTHOR]

Background The platelet (PLT) storage environment triggers the formation of surface-attached aggregates known as biofilms by the common PLT contaminant Staphylococcus epidermidis. The biofilm matrix is largely composed of polysaccharide intercellular adhesin ( PIA) mediated by the icaADBC operon. However, PIA-negative S. epidermidis has been reported to form biofilms in PLT concentrates ( PCs). Since biofilm formation is associated with increased virulence, this study was aimed at determining if PIA-negative S. epidermidis grown in PCs presents enhanced virulence using the nematode Caenorhabditis elegans as a host model for bacterial pathogenesis. Study Design and Methods Biofilm-positive S. epidermidis ATCC 35984 and 9142, which carry the icaADBC operon, and biofilm-negative S. epidermidis ATCC 12228 and 9142 Δ icaA were grown in regular media and in PCs and biofilm formation was quantified using a crystal violet assay. The virulence of these strains after passage through PCs was tested using nematode killing assays. Nematode survival was calculated using the Kaplan- Meier method and statistical differences were determined by log-rank analysis. Results All S. epidermidis strains were able to form biofilms in PCs. Although persistence of a biofilm-positive phenotype in the biofilm-negative strains grown in PCs was not observed after passage in regular medium, the virulence of all strains was significantly increased as demonstrated by shortened life spans of the nematodes in C. elegans killing assays. Conclusion Our findings highlight the potential of an increased risk of nosocomial infections caused by S. epidermidis in transfusion recipients since PC storage conditions promote biofilm formation, and possibly pathogenicity, of strains traditionally known to be attenuated for virulence. [ABSTRACT FROM AUTHOR]

Ochradenus baccatus is a widely distributed shrub in desert regions of the Middle East and North Africa. This plant's nematicidal activity against the root-knot nematode Meloidogyne javanica was evaluated because it has been found to contain exceptionally high levels of glucosinolates. In in vitro assays with aqueous extracts of the plant, 100% of second-stage juveniles were immobilized after exposure to 4% root-core extract for 48 h; 8% root-core extract suppressed their hatching by 87%, whereas stem, flower and root bark showed lower activity. Incorporation of root core or bark into the soil, as fresh or dry powder at 1 and 0·5% (w/w), respectively, reduced the number of nematodes recovered from the soil by 95-100%, whereas the flower and stem were much less effective. Results from further pot experiments indicated that only the root bark consistently contains nematicidal compounds which are effective in soil, whereas the nematicidal activity of the root core in soil was inconsistent. The presence of non-volatile lipophilic and lipophobic nematicidal compounds in the root bark was suggested by extraction with different polar solvents, but these compounds do not seem to be isothiocyanates - glucosinolate-hydrolysed compounds with nematicidal activity. Very poor host status of Ochradenus baccatus to M. javanica, M. incognita and M. hapla, but with root-penetration rates of juveniles similar to those in tomato roots, suggest that this plant may be used as a cover plant or trap plant to reduce nematode populations in the soil. [ABSTRACT FROM AUTHOR]

The article presents abstracts on plant nematodes which include the causes for Litchi tree die-back, the use of nematicides as an alternative to control plant nematodes and the management of nematode.

In vitro and glasshouse studies were initiated to determine the mechanisms of action of an aqueous garlic extract, salicylaldehyde, a nonylphenol ethoxylate surfactant and a formulation (G8014S) containing these substances on the potato cyst nematode Globodera pallida. The effects of these substances on host finding and migration of second-stage juveniles (J2) were assessed by investigating their ability to migrate through a sand column and towards potato roots in Pluronic F-127 gel. The garlic extract was shown to be the least disruptive to J2 host finding, reducing attraction by between 13 and 24% at concentrations of 7840 μl I-1 and 983 μl I-1, respectively. By contrast, a reduction of approximately 38% in J2 attraction to roots was achieved by treating J2 with 344 μl I-1 of G8014S. Of all the substances tested, salicylaldehyde was the least attractive to G. pallida J2 (4.1%) while the garlic extract and oxamyl treatments attracted 43.5 and 28.9% J2, respectively. In glasshouse experiments, different rates of the test substances were compared with the nematicide oxamyl for their effects on the in-soil hatch, egg viability and multiplication of G. pallida. The effect of treatment with 220.16 1 ha-1 of G8014S on G. pallida multiplication in the glasshouse was comparable to that of oxamyl causing a five-fold reduction in PCN multiplication relative to the water control. These results provide evidence to support the potential of the formulation for the control of G. pallida in potatoes. [ABSTRACT FROM AUTHOR]