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Summary: Green soybean (edamame), an early-harvested soybean, is a popular vegetable in Asia and is recognised as a healthy vegetable in the other parts of the world. In Japan, edamame yield has gradually decreased over the last 30 years, despite similar cultivation areas. Damage caused by the soybean cyst nematode (SCN), Heterodera glycines , is one of the main causes. We surveyed the distribution of SCN in different locations and found a wide distribution of SCN across Japan. Different control measures are available, such as chemical control using fumigants or a granular type of nematicide, solarisation, and rotation with non-host crops. We are developing a new type of biological control method, which comprises short-term field cultivation and soil incorporation of mung bean. This method not only decreases the SCN density in soil but also mitigates soil erosion and nitrate leaching. For future SCN control it is essential to establish an environmentally friendly management strategy. [ABSTRACT FROM AUTHOR]

Nematodes are a common soybean threat, and the search for new solutions for controlling them has been the focus of many studies worldwide. Crotalaria spp. are known sources of pyrrolizidine alkaloids with nematicidal activities. In this study, the nematicidal and nematostatic effects of C. spectabilis extracts were evaluated in vitro over two different nematode species (Heterodera glycines and Meloidogyne javanica). A full factorial experimental design was employed to understand the effects and interactions of input factors (plant organ, extraction solvent, and nematode species) on the output response (nematode mortality). Ethanolic and alkaline extracts of leaves and seeds were tested at concentrations of 5, 10 and 20 mg L-1 in bioassays with 48 hours of incubation. The C. spectabilis seed's alkaline extract assessed for H. glycines resulted in higher mortality rates (close to 96%) compared to the other experiments. Therefore, this combination was also evaluated in vivo in a soybean plantation, resulting in a decrease of about 90% in the nematode multiplication factor compared to the control group. Ultra-High Performance Liquid Chromatography coupled to a tandem High-Resolution Mass Spectrometer (UHPLC-HRMS/MS) analyses revealed pyrrolizidine alkaloids in the extract, such as senecionine N-oxide, besides monocrotaline and its derivatives. The results obtained in this study allow new possibilities to handle nematode infections. The direct application of C. spectabilis extracts or their isolated bioactive compounds on soil can be a promising approach. [ABSTRACT FROM AUTHOR]

Summary: Purpureocillium lilacinum is a potent biocontrol agent against Meloidogyne spp. and various other plant-parasitic nematodes in crops. However, existing commercial formulations of P. lilacinum suffer from drawbacks like short shelf life and inconsistent performance in different environmental conditions. To address these issues, a new nano-formulation of P. lilacinum was developed and tested against Meloidogyne incognita infecting tomatoes. Initially, edible oil-based emulsions were prepared using probe ultrasonication, with 40 formulations screened and 14 selected for further testing. Seven of these emulsions remained stable at room temperature (28 ± 4°C) for 8 weeks, with stability assessed based on particle size, zeta potential, and particle shape using particle size analysis and transmission electron microscopy (TEM). Among these, NE 8 (comprising 10 ml of 1% carboxyl methyl cellulose (CMC), 1.25 ml of Tween 80 and 5 ml of sunflower oil) exhibited superior characteristics, with an average particle size of 226.6 nm, a zeta potential of −54.80 mV, and a spherical morphology under TEM examination. The P. lilacinum nanoemulsion formulation was produced by homogenising NE 8 emulsion and spores at a 1:1 ratio, ensuring efficient spore dispersion and encapsulation without loss of viability. In vitro tests demonstrated 100% immobility of M. incognita second-stage juveniles (J2) and 100% parasitism of eggs at a concentration of 5.0 ml l−1. Under glasshouse conditions, soil drenching with the nano-formulation at concentrations ranging from 0.5 to 5.0 ml l−1 resulted in enhanced tomato growth and significant suppression of M. incognita populations in soil and roots, with increased egg mass parasitism. Bio-safety tests confirmed that P. lilacinum nano-formulation at concentrations of 0.25 ml l−1 and 5.0 ml l−1 had no harmful effects on the earthworm Eudrilus eugeniae. [ABSTRACT FROM AUTHOR]

The latest study published in Nature by Andrew R. Burns, Peter J. Roy and co-authors is highlighted in this paper, they investigated a series of novel nematicidal compounds, including Selectivin-A and Selectivin-E, and explored their mechanism of action. Experiments have displayed that the Selectivin compound is inactive to human cells, fish, fungi, insects and even beneficial nematodes. In the exploration of its mechanism of action, it was found that the mechanism of action of Selectivin is different with those of commercial nematocides: Selectivin needs to be activated by biotin produced by nematodes, after that they can be transformed into compounds with high nematicidal activity. This proves that the family of Selectivin compounds has the advantages of high selectivity and environmental friendliness, and their mechanism of action is completely new, proposing a completely new path for the development of new nematicides.

Plant-parasitic nematodes (PPNs) reduce the high profitability of many crops and degrade their quantitative and qualitative yields globally. Traditional nematicides and other nematode control methods are being used against PPNs. However, stakeholders are searching for more sustainable and effective alternatives with limited side effects on the environment and mankind to face increased food demand, unfavorable climate change, and using unhealthy nematicides. This review focuses on upgrading the pre-procedures of PPN control as well as novel measures for their effective and durable management strategies on economically important crops. Sound and effective sampling, extraction, identification, and counting methods of PPNs and their related microorganisms, in addition to perfecting designation of nematode–host susceptibility/resistance, form the bases for these strategies. Therefore, their related frontiers should be expanded to synthesize innovative integrated solutions for these strategies. The latter involve supplanting unsafe nematicides with a new generation of safe and reliable chemical nematicidal and bionematicidal alternatives. For better efficacy, nematicidal materials and techniques should be further developed via computer-aided nematicide design. Bioinformatics devices can reinforce the potential of safe and effective biocontrol agents (BCAs) and their active components. They can delineate the interactions of bionematicides with their targeted PPN species and tackle complex diseases. Also, the functional plan of nematicides based on a blueprint of the intended goals should be further explored. Such goals can currently engage succinate dehydrogenase, acetylcholinesterase, and chitin deacetylase. Nonetheless, other biochemical compounds as novel targets for nematicides should be earnestly sought. Commonly used nematicides should be further tested for synergistic or additive function and be optimized via novel sequential, dual-purpose, and co-application of agricultural inputs, especially in integrated pest management schemes. Future directions and research priorities should address this novelty. Meanwhile, emerging bioactivated nematicides that offer reliability and nematode selectivity should be advanced for their favorable large-scale synthesis. Recent technological means should intervene to prevail over nematicide-related limitations. Nanoencapsulation can challenge production costs, effectiveness, and manufacturing defects of some nematicides. Recent progress in studying molecular plant–nematode interaction mechanisms can be further exploited for novel PPN control given related topics such as interfering RNA techniques, RNA-Seq in BCA development, and targeted genome editing. A few recent materials/techniques for control of PPNs in durable agroecosystems via decision support tools and decision support systems are addressed. The capability and effectiveness of nematicide operation harmony should be optimized via employing proper cooperative mechanisms among all partners. [ABSTRACT FROM AUTHOR]

Summary: Classical methods of using many toxic chemical pesticides for managing plant-parasitic nematodes (PPN) on key crops are inappropriate and have unfavourable consequences on human health and the environment. By contrast, nanotechnology can provide a wide range of alternative applications with additional merits based on nanoparticle (NP) pesticides. Three major categories, i.e. , physical, chemical and biological methods, have been generally used for synthesis of nanonematicides. The merits and demerits of these methods are highlighted. The biological method generally involves easy, fast, scalable, cheap and environmentally safe techniques. As nanonematicides can reduce the non-selective use of classical nematicides with their high pollution and unhealthy levels, mechanisms underlying PPN population suppression by these nanonematicides are presented to help in their further optimisation. Nanonematicides are guiding a radical change in their efficacy against PPN, but more attention should be given to secure their clean production and application with cost-effective methods. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Anatolian Environmental & Animal Science is the property of Bulent Verep and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Isolation on culture media followed with macroscopic, microscopic, molecular and phylogenetic analyses and pathogenicity tests allowed us to identify Pythium capillosum to be capable of destroying dagger nematode through endozoic parasitism from ingested oomycete zoospores. Although endoparasitism of free-living nematodes is found to be common among oomycetes in nature, this is the first finding of such occurrence in Bosnia and Herzegovina soils. The obtained results could open the door to future studies for controlling nematodes in an environmentally safe and sustainable way. [ABSTRACT FROM AUTHOR]

Plant-parasitic nematodes conduct a series of sophisticated behaviors to complete their life cycles. Among these, locomotion behaviors, including finding the host and migrating to the feeding site, directly affect the success of parasitism. Thus, disrupting locomotion behaviors has the potential to control these parasites. γ-Aminobutyric acid (GABA) is the prominent inhibitory neurotransmitter in nematodes. GABA-immunoreactive neurons are mostly found in motor neurons, where they regulate behaviors in the model nematode C. elegans. However, the GABA system in most stylet-bearing nematodes has received little attention. Using immunohistochemistry, we found variation in the pattern of GABA-immunoreactivity among two major plant-parasites and a fungal feeder. Some of these GABA-immunoreactive neurons lack clear homologs to C. elegans. Pharmaceutical assays showed that applying GABA, its agonist, and its antagonist, can disrupt the locomotion behaviors of these nematodes, although sensitivity to a given compound varied between species. Our data suggest that the GABA system is a potential target for the control of plant-parasitic nematodes.

Summary: Demand for Florida organic strawberries has significantly increased in recent years, yet this industry is threatened by pests and pathogens that often come with transplants from out-of-state nurseries. Plant steaming has been explored as an alternative to reduce those threats in transplants. This study evaluated the yield performance of seven strawberry cultivars and their impact on nematode densities and plant vigour after steaming was applied to transplants imported from California during two growing seasons (2020-2021 and 2021-2022). The cultivars used were 'Sensation® Florida127', 'Florida Brilliance', 'Florida Radiance', 'Winterstar™ FL 05-107', 'Florida Elyana', 'Strawberry Festival' and 'Florida Beauty'. Plant steaming reduced plant vigour only 4 weeks after transplanting. Nevertheless, no negative effect was observed in total fruit yield. Differences among cultivars were observed for plant vigour, total fruit yield and abundance of root-knot nematodes. The plant vigour of each cultivar depended on the time of the year, which varied significantly throughout the season. Cultivars 'Sensation® Florida127' and 'Florida Radiance' attained the highest total yield in both seasons. There was an effect of the cropping system in the nematode community, which increased the bacterivores but drastically reduced omnivores and ring nematodes over time. No effect of cultivar was observed in plant-parasitic nematode populations. The cultivar 'Winterstar™ FL 05-107' was an exception since Meloidogyne javanica population densities were significantly higher in 'Winterstar™ FL 05-107's experimental plots. Overall, transplant steaming shows the potential to be a component of an integrated pest and disease management programme for the success of sustainable and profitable yields [ABSTRACT FROM AUTHOR]

Pathogenicity of root-knot nematodes on tomato (Solanum lycopersicum L .) in soil amended with different sources of green manure was investigated at the research and teaching farm of Federal College of Agriculture Ishiagu, Ebonyi State, Nigeria, during the 2022 and 2023 cropping seasons. Hedge fig plants, African peach plants, and banana leaves at 10t/ha were used as green manure sources while the control plots did not receive any treatment. The experimental design used was a Randomized Complete Block Design (RCBD) with the four treatments replicated three times. Growth and yield parameters were evaluated from plant height, number of leaves, number of fruits, and weight of fruit at harvest while disease parameters were obtained from number of galled roots and number of galls per root. Data collected were averaged over the two cropping seasons and analyzed using analysis of variance (ANOVA) and significant treatment means were separated using least significant difference (LSD). All inferences were made at a 5% level of probability. The results showed that the treatments significantly (P<0.05) increased the plant heights at 6 and 9 weeks after transplanting. The treatments did not have any significant (P>0.05) effect on the number of leaves produced by the plants. The number and weight of fruits at harvest were significantly (P<0.05) increased by the treatments. The number of galled roots was significantly (P<0.05) reduced at the application of hedge plant leaves at 10 t/ha while there was no significant (P>0.05) effect on the gall index of the treatments at harvest when compared with other treatments and it was recommended for tomato farmers as an alternative to inorganic nematicide . [ABSTRACT FROM AUTHOR]

Plant-parasitic nematodes (PPNs) reduce the high profitability of many crops and degrade their quantitative and qualitative yields globally. Traditional nematicides and other nematode control methods are being used against PPNs. However, stakeholders are searching for more sustainable and effective alternatives with limited side effects on the environment and mankind to face increased food demand, unfavorable climate change, and using unhealthy nematicides. This review focuses on upgrading the pre-procedures of PPN control as well as novel measures for their effective and durable management strategies on economically important crops. Sound and effective sampling, extraction, identification, and counting methods of PPNs and their related microorganisms, in addition to perfecting designation of nematode–host susceptibility/resistance, form the bases for these strategies. Therefore, their related frontiers should be expanded to synthesize innovative integrated solutions for these strategies. The latter involve supplanting unsafe nematicides with a new generation of safe and reliable chemical nematicidal and bionematicidal alternatives. For better efficacy, nematicidal materials and techniques should be further developed via computer-aided nematicide design. Bioinformatics devices can reinforce the potential of safe and effective biocontrol agents (BCAs) and their active components. They can delineate the interactions of bionematicides with their targeted PPN species and tackle complex diseases. Also, the functional plan of nematicides based on a blueprint of the intended goals should be further explored. Such goals can currently engage succinate dehydrogenase, acetylcholinesterase, and chitin deacetylase. Nonetheless, other biochemical compounds as novel targets for nematicides should be earnestly sought. Commonly used nematicides should be further tested for synergistic or additive function and be optimized via novel sequential, dual-purpose, and co-application of agricultural inputs, especially in integrated pest management schemes. Future directions and research priorities should address this novelty. Meanwhile, emerging bioactivated nematicides that offer reliability and nematode selectivity should be advanced for their favorable large-scale synthesis. Recent technological means should intervene to prevail over nematicide-related limitations. Nanoencapsulation can challenge production costs, effectiveness, and manufacturing defects of some nematicides. Recent progress in studying molecular plant–nematode interaction mechanisms can be further exploited for novel PPN control given related topics such as interfering RNA techniques, RNA-Seq in BCA development, and targeted genome editing. A few recent materials/techniques for control of PPNs in durable agroecosystems via decision support tools and decision support systems are addressed. The capability and effectiveness of nematicide operation harmony should be optimized via employing proper cooperative mechanisms among all partners.

Summary: Limited information is available regarding the susceptibility or resistance of soybean cultivars to Meloidogyne enterolobii. Recently, a new race of this species was detected in Brazil parasitising cotton and soybean. This nematode has the potential to pose a problem in both of these crops, since it is pathogenic and virulent to several economically important plants that have resistance genes to other Meloidogyne species. The aim of this study was to assess the responses of EMBRAPA's main soybean cultivars with confirmed resistance to M. incognita and M. javanica to the two races of M. enterolobii detected in Brazil. Additionally, this study aimed to characterise the aggressiveness of these nematode races. The experiments were conducted in a plastic house, in a factorial scheme with 16 soybean cultivars × two M. enterolobii races (guava and cotton), totalling 32 treatments × eight replications, and evaluated with two replications over time. Soybean sowing took place in pots containing 1.7 l of a mixture of soil, sand and Bioplant® substrate (1:1:1), previously autoclaved. Each soybean plant was inoculated with 5000 eggs of M. enterolobii. After 75 days for the first experiment, and 90 days for the second, the following variables were evaluated: gall index (GI), egg mass index (EMI), total number of eggs per g root (NEGR) and the reproduction factor (RF). Both races of M. enterolobii showed reproductive ability in all soybean genotypes (with or without known genetic resistance), albeit with moderate to low values in comparison to their reproduction on tomato plants. The race from cotton was considered statistically more aggressive than the guava population on soybean cultivars. Only 'BRS 7180 IPRO' was moderately resistant to both races in both experiments. In view of the importance and prospects for expansion of the soybean crop, the findings of this study contribute to a better understanding of the resistance and aggressiveness exhibited by the two races of M. enterolobii , Moreover, the study highlights the significant challenge that lies ahead in developing breeding programmes to select soybean genotypes with multiple resistance to Meloidogyne spp. [ABSTRACT FROM AUTHOR]

The stem and bulb nematode Ditylenchus dipsaci is one of the most important plant-parasitic nematodes with a worldwide distribution, causing damage mainly in temperate regions. Onion, garlic and alfalfa are its main hosts. The use of nematode-free seeds and plant propagation materials, crop rotation, resistant cultivars and chemical nematicides are common methods of its management. Due to the side effects of nematicides on human health and the environment, the use of safe, cost-effective alternative methods are necessary. In this study, the nematicidal effects of the essential oils of mountain thyme, oregano, clove, sage and savory as well as the metabolites of the fungus Scytalidium sp. were studied in comparison to metam sodium under laboratory conditions. To prepare the nematode population, nematodes were extracted from naturally infected garlic from the Gogan region of East Azarbaijan province, reared on carrot discs and incubated at 18 ± 1°C for 60 days. The effects of plant essential oils, fungal metabolites and metam sodium were investigated in bioassays with four replicates, and nematode mortality was recorded after 24 and 48 hours. After a probit analysis, the LC50 and LC90 values were calculated for each of the compounds tested. After 24 hours, the LC50 values for the essential oils clove, oregano, marzeh and thyme were 1748, 769.2, 1662 and 4913 ppm, respectively, and for the fungal metabolite and metam sodium were 207.6 and 6.7 ppm, respectively. Gas chromatography with a mass spectrometer (GC-MS) and a DB5 column was used to identify the components of the essential plant oils and the metabolites, the results of which are presented here. Based on the LC50 values, the compounds tested caused mortality and population decline of D. dipsaci at relatively low concentrations, with the exception of sage-flower. [ABSTRACT FROM AUTHOR]

Plant-parasitic nematodes (PPN) pose a significant threat to agricultural productivity by causing extensive damage to various crops worldwide. Their complex life cycle and ability to persist in soils make nematode management difficult. Chemical control strategies are emerging as effective but often result in environmental and ecological risks. Biocontrol agents offer a promising alternative with the desired level of reduction in nematode populations without harming non-target organisms. Among the nematode antagonists, Streptomyces spp. is an effective candidate with their ability to produce secondary metabolites that exhibit potent nematicidal properties. Streptomyces avermitilis is the one species that has been completely exploited for nematode and insect management. This review highlights the role of Streptomyces spp. other than S. avermitilis in phytonematode management. Few Streptomyces spp. such as S. yatensis, S. pactum, S. rochei, S. rubrogriseus, S. lincolnensis, S. hygroscopicus, S. antibioticus strain M7, S. albogriseolus ND41 and S. fimicarius D153 are reported to have nematode control potential. Arenimycin, carboxamycin, fervenulin, hygromycin, and lincomycin are some of the Streptomyces- derived compounds that proved to have nematicide potential. Streptomyces spp. also acts as an elicitor of plant defense against nematode intruders. They evinced endophytic potential, plant growth promotion mechanism, compatible nature with other antagonists, and safe to non-target organisms. This current review also highlights the direct and indirect mechanisms by which they control nematodes, another beneficial role in plants, and strategies to upgrade them as commercial products in future thrust areas. [Display omitted] • Plant-parasitic nematodes wreak havoc on crops globally, endangering agricultural productivity. • The resilient and complex life cycle of nematodes demands innovative and effective control strategies. • Streptomyces spp., offer an eco-friendly alternative with minimal harm to non-target organisms. • Streptomyces provide an eco-friendly solution to nematode management by targeting pests without harming beneficial organisms. • Streptomyces with their potent nematicidal compounds, plant-boosting abilities hold promise for future commercial products. [ABSTRACT FROM AUTHOR]

Summary: Potato cyst nematodes (PCN), Globodera spp., cause damage to potatoes in more than 60 countries and several management strategies, including the application of chemical nematicides, are commonly used for their control. However, due to stringent regulations in Europe several nematicides have been, or are being, removed from the market due to their potential toxic effects on the environment and human health. New solutions and nematode management strategies are being sought to control these challenging and economically important nematodes. In this study, the effects of Salibro™, a novel sulfonamide nematicide based on the active ingredient fluazaindolizine (Reklemel™ active), were evaluated on the hatching, motility, infectivity and reproduction of PCN in the laboratory. Depending upon the duration of nematode pre-exposure, Salibro™ at concentrations of 5-250 mg fluazaindolizine (active substance) (a.s.) kg−1 (equivalent to 5-250 ppm a.s.) affected hatching, motility and infectivity of second-stage juveniles of G. pallida and G. rostochiensis , whereas the reproduction of G. pallida was only influenced at 5-50 mg a.s. kg−1. Salibro™, under laboratory conditions, has intrinsic activity against both PCN species and could be a promising additional tool for the integrated management of PCN. Further studies are needed to demonstrate Salibro™ efficacy under field conditions. [ABSTRACT FROM AUTHOR]

Summary: The increasing interest in agroecological practices and the current consideration of agrarian soils as a sustainable resource are driving the development of new strategies to manage soil parasites and diseases. The application of organic matter from different sources to reduce plant parasites contributes to circular economy by applying by-products as soil organic amendments that reduce wastes. Wine vinasse (WV) is a by-product generated to obtain alcohol from wine by physical methods in distilleries. The aim of this study was to determine the potential of WV and its combination with animal manure (WV+M) as soil biodisinfestation products. For this, it was compared with a plastic-covered control to distinguish the biodisinfestation from solarisation effect. The crops tested consisted of a tomato-Swiss chard rotation under glasshouse conditions. Their effects on Meloidogyne incognita , soil fertility, nematode community and crop yield were assessed. The results obtained after two seasons showed a reduction of M. incognita galling in the root system of both crops. The immediate effect after the treatment application was a reduction in the abundance of nematodes and changes in the nematode-based indices that affected all plots, including the control, most likely related to the tillage effect for the treatments application and the plastic cover. Soil fertility was improved by the application of WV (NO3−, Bioav. P) and WV+M (C, Ntotal, K), which reduced herbivore nematode metabolic footprints and enhanced bacterivore footprints. Our results indicate that the combination WV+M was effective reducing M. incognita infection, and improved crop yield. Use of by-products such as WV is a helpful tool for managing horticultural soils. [ABSTRACT FROM AUTHOR]

[Display omitted] Nematodes are hidden enemies that inhibit the entire ecosystem causing adverse effects on animals and plants, leading to economic losses. Management of foliar phytoparasitic nematodes is an excruciating task. Various approaches were used to control nematodes dispersal, i.e., traditional practices, resistant cultivars, plant extract, compost, biofumigants, induced resistance, nano-biotechnology applications, and chemical control. This study reviews the various strategies adopted in combating plant-parasitic nematodes while examining the benefits and challenges. The significant awareness of biological and environmental factors determines the effectiveness of nematode control, where the incorporation of alternative methods to reduce the nematodes population in plants with increasing crop yield. The researchers were interested in explaining the fundamental molecular mechanisms, providing an opportunity to deepen our understanding of the sustainable management of nematodes in croplands. Eco-friendly pesticides are effective as a sustainable nematodes management tool and safe for humans. The current review presents the eco-friendly methods in controlling nematodes to minimize yield losses, and benefit the agricultural production efficiency and the environment. [ABSTRACT FROM AUTHOR]

Copyright of Tobacco Science & Technology is the property of Tobacco Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: In this study, we aimed to evaluate the nematicidal activity of cinnamon bark extracts (CE) and chitosan (Cs) against Meloidogyne incognita and Pratylenchus coffeae under pot and field conditions. In the pot experiments, CE mixed with Cs effectively inhibited M. incognita and P. coffeae infection on robusta coffee plants. The formulations applied, CE:Cs = 8 mg:30 mg, CE:Cs = 16 mg:60 mg and CE:Cs = 16 mg:60 mg per pot, significantly reduced the gall index and nematode number in 5 g of root and 100 g of soil. In addition, the application of CE:Cs = 48 mg:180 mg CE:Cs = 80 mg:300 mg and CE:Cs = 112 mg:420 mg plant−1 effectively reduced root gall formation and nematode density in roots and soil compared with the non-treated control under field conditions. Nematode density in the roots was positively correlated with the rate of yellow leaf disease. These results suggest that cinnamon mixed with chitosan may be used as an effective eco-friendly pesticide against plant-parasitic nematodes. [ABSTRACT FROM AUTHOR]

Summary: Currently a renaissance in chemical nematicides is taking place with novel products like Nimitz® (a.s. fluensulfone), Velum Prime® (a.s. fluopyram) and Salibro™ (a.s. fluazaindolizine – Reklemel™ active) entering the marketplace. Although a considerable amount of published data is already available on their laboratory and field impact on plant-parasitic nematodes, little is understood of their compatibility with the beneficial or free-living nematodes that are part of the soil health network. In a range of laboratory studies, the effects of these nematicides on the vitality and reproduction of several species was tested, including both cosmopolitan free-living nematodes (Acrobeloides , Cruznema , Panagrobelus) as well as commercially applied entomopathogenic nematodes (Steinernema , Heterorhabditis). Within aqueous exposure and agar plate in vitro assays, species sensitivity to those nematicides differed significantly but their fitness (vitality and reproduction; infectivity to insect hosts) was generally not adversely impacted by concentrations of 5-50 ppm (a.s.) of Salibro. Even at 250 ppm (a.s.) of Salibro only some species of the bacterial-feeding species showed some negative impact. By contrast, both Nimitz at 50 ppm (a.s.) and Velum at 5 ppm (a.s.) consistently demonstrated stronger adverse impacts. In second level soil drenching assays, either no, or occasionally slight, adverse effects on the natural community of free-living nematodes were observed if soils were drenched with different volumes of Salibro at 5-50 ppm (a.s.), while relatively stronger reductions were measured within the plant-parasitic species (especially root-knot nematodes). Both Nimitz and Vydate (a.s. oxamyl) showed some degree of compatibility at 5 and 25 ppm (a.s.), respectively, which was generally higher than for Velum Prime at 5 ppm (a.s.). Overall, these data indicate that, when used at common field rates, Salibro will be one of the best options as part of integrated nematode management programmes where the use of chemical nematicides is required. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

No nematicide has been registered for controlling plant-parasitic nematodes in sugarcane in Japan. Greenhouse and field experiments were conducted to evaluate the efficacy of the phenylpyrazole insecticide fipronil (0.3–0.45 kg a.i./ha) against the root-lesion nematode, Pratylenchus zeae, which is an important plant-parasitic nematode species associated with sugarcane (Saccharum spp. hybrids) in Okinawa, Japan. Both experiments showed a reduction of P. zeae population densities in sugarcane roots to 27 to 56% of the non-treated control after 7 wk in the greenhouse experiment and 3 months in the field experiment (two trials). In contrast, P. zeae population densities in soil were not reduced by the fipronil treatment. At harvest, sugarcane yields in the field experiment were significantly increased by 6 to 8% in the fipronil treated plots compared to the non-treated control. The data showed that fipronil reduced numbers of P. zeae in sugarcane roots at the early stage of sugarcane seedling growth resulting in increased sugarcane yields. This is the first report of nematicidal activity of fipronil against P. zeae under field conditions.

Control of plant-parasitic nematodes (PPNs) via host-induced gene silencing (HIGS) involves rational selection of genes and detailed assessment of effects of a possible knockdown on the nematode. Some genes by nature may be very important for the survival of the nematode that knockdown may be resisted. Possible silencing and effects of 20 such genes involved in the RNA interference (RNAi) pathways of Meloidogyne incognita were investigated in this study using long double-stranded RNAs (dsRNAs) as triggers. Two of the genes, ego-1 and mes-2, could not be knocked down. Expression of six genes (xpo-1, pash-1, xpo-2, rha-1, ekl-4, and csr-1) were significantly upregulated after RNAi treatment whereas for 12 of the genes, significant knockdown was achieved and with the exception of mes-2 and mes-6, RNAi was accompanied by defective phenotypes in treated nematodes including various degrees of paralysis and abnormal behaviors and movement such as curling, extreme wavy movements, and twitching. These abnormalities resulted in up to 75% reduction in infectivity of a tomato host, the most affected being the J2s previously treated with dsRNA of the gfl-1 gene. For 10 of the genes, effects of silencing in the J2s persisted as the adult females isolated from galls were under-developed, elongated, and transparent compared to the normal saccate, white adult females. Following RNAi of ego-1, smg-2, smg-6, and eri-1, reduced expression and/or the immediate visible effects on the J2s were not permanent as the nematodes infected and developed normally in tomato hosts. Equally intriguing was the results of RNAi of the mes-2 gene where the insignificant change in gene expression and behavior of treated J2s did not mean the nematodes were not affected as they were less effective in infecting host plants. Attempt to silence drsh-1, mut-7, drh-3, rha-1, pash-1, and vig-1 through HIGS led to reduction in nematode infestation by up to 89%. Our results show that genes may respond to RNAi knockdown differently so an exhaustive assessment of target genes as targets for nematode control via RNAi is imperative.

Introduction: Crotalaria spectabilis is an important species used as a pre‐plant cover for soybean crops to control the proliferation of endoparasitic nematodes. Species from the Crotalaria genus are known for presenting pyrrolizidine alkaloids (PAs) in their composition, however, C. spectabilis is still considered chemically under‐explored. Objective: The goal of this manuscript is the development and validation of a method for PAs and flavonoids identification and quantification of C. spectabilis seeds and leaves, a toxic plant used for nematode proliferation control in soil, especially in soybean crops. Materials and methods: Seeds and leaves extracts were analysed by high‐performance liquid chromatography coupled to tandem mass spectrometry (HPLC‐MS/MS) for the identification of the compounds. Results: PAs and phenolic compounds could be identified in both samples based on the MS/MS fragmentation pattern. Molecular formulas of the annotated compounds were confirmed by ultra‐high‐performace liquid chromatography‐quadrupole time‐of‐flight (UHPLC‐QToF), and monocrotaline could also be confirmed by standard comparison. The quantification of monocrotaline was performed by HPLC‐MS/MS, resulting in 123 times higher monocrotaline content in seeds than in the leaves, which could explain its efficiency in combating nematode proliferation in soil. Conclusion: This was the first report of phenolic compounds in C. spectabilis. The current study highlights the importance of C. spectabilis for nematode control due to the presence of toxic PAs, and the employment of analytical techniques for identification and quantification of compounds present in the extracts. Crotalariaspectabilis is an important species used as pre‐plant cover for soybean crops to control the proliferation of endoparasitic nematodes. A validated method for pyrrolizidine alkaloids (PAs) and flavonoids identification and quantification of Crotalaria spectabilis seeds and leaves was performed by HPLC‐MS/MS, resulting in about 120 times higher monocrotaline content in seeds than in the leaves, which could explain its efficiency in combating nematode proliferation in soil. [ABSTRACT FROM AUTHOR]

The results indicated that the application of Pseudomonas fluorescens was better that minimized lesion nematode population by 73.2% and enhanced germination %, number of tillers, commercial cane sugar %, cane yield and sugar yield by 87.2, 161.5, 12.7, 121.4 and 16.4%, respectively. This field experiment was repeated once during 2016-2017 and obtained 74.0% control of lesion nematode with higher yield of 124.4 t/ha in P. fluorescens @ 2.5 kg/ha sett treatment. Simultaneously another field experiment with fungal antagonists Purpureocillium lilacinum and Trichoderma viride @ 2.5 kg/ha were conducted during 2015-2016 and 2016-2017. The P. lilacinum was better than T. viride. During 2016-2017, similar results recorded 70.5% nematode control with cane yield 124.8 t/ha. The results demonstrated that P. fluorescens in combination of neem cake was better that caused the highest reduction in lesion nematode population (74.8%) with the cane yield of 115.8 t/ha. [ABSTRACT FROM AUTHOR]

Summary: Incorporation of castor bean cake into the soil results in the emission of four main compounds: skatole, γ -decalactone, 4-methylphenol and phenol. The toxic effects of these compounds on the life cycle of Meloidogyne incognita were studied here. Only phenol did not reduce hatching of M. incognita second-stage juveniles (J2) at any of the concentrations tested. The other compounds reduced J2 hatching by 42.1 to 59.3% at the highest concentrations. When J2 were immersed in Tween 80® solutions of each compound, at their respective LC50 values and inoculated into soil with tomato plants, reductions in the numbers of galls (48.5-69.3%) and eggs (42.8-62.5%) were observed in comparison with the control; this result was similar to that of carbofuran. The highest reductions in the numbers of galls (21.8-88.5%) and eggs (49.6-98.9%) occurred with all compounds when the highest concentration (500 mg l−1) was applied to the substrate at the moment of J2 inoculation. Volatile compounds of γ -decalactone and skatole failed to cause J2 immobility or mortality. However, phenol caused 95.8% and 4-methylphenol caused 100% mortality. With fumigation, the highest concentration (1000 mg (l substrate)−1) of any tested compound reduced gall numbers at a similar rate to the nematicide dazomet (98.7-100%) and reduced egg numbers (87.1-99.7%). The volatile compounds skatole, γ -decalactone, 4-methylphenol and phenol have a nematicidal effect on the life cycle of M. incognita and alter its pathogenic behaviour on the plant. [ABSTRACT FROM AUTHOR]

Control of plant-parasitic nematodes (PPNs) via host-induced gene silencing (HIGS) involves rational selection of genes and detailed assessment of effects of a possible knockdown on the nematode. Some genes by nature may be very important for the survival of the nematode that knockdown may be resisted. Possible silencing and effects of 20 such genes involved in the RNA interference (RNAi) pathways of Meloidogyne incognita were investigated in this study using long double-stranded RNAs (dsRNAs) as triggers. Two of the genes, ego-1 and mes-2, could not be knocked down. Expression of six genes (xpo-1, pash-1, xpo-2, rha-1, ekl-4, and csr-1) were significantly upregulated after RNAi treatment whereas for 12 of the genes, significant knockdown was achieved and with the exception of mes-2 and mes-6, RNAi was accompanied by defective phenotypes in treated nematodes including various degrees of paralysis and abnormal behaviors and movement such as curling, extreme wavy movements, and twitching. These abnormalities resulted in up to 75% reduction in infectivity of a tomato host, the most affected being the J2s previously treated with dsRNA of the gfl-1 gene. For 10 of the genes, effects of silencing in the J2s persisted as the adult females isolated from galls were under-developed, elongated, and transparent compared to the normal saccate, white adult females. Following RNAi of ego-1, smg-2, smg-6, and eri-1, reduced expression and/or the immediate visible effects on the J2s were not permanent as the nematodes infected and developed normally in tomato hosts. Equally intriguing was the results of RNAi of the mes-2 gene where the insignificant change in gene expression and behavior of treated J2s did not mean the nematodes were not affected as they were less effective in infecting host plants. Attempt to silence drsh-1, mut-7, drh-3, rha-1, pash-1, and vig-1 through HIGS led to reduction in nematode infestation by up to 89%. Our results show that genes may respond to RNAi knockdown differently so an exhaustive assessment of target genes as targets for nematode control via RNAi is imperative. [ABSTRACT FROM AUTHOR]

Summary: There is a demand for novel products for the control of plant-parasitic nematodes, so we characterised the effectiveness of some plant essential oils against Meloidogyne incognita and verified the efficiency of the major component from the most toxic oils and their analogues using in vitro and in vivo assays. In this study, the essential oils from Piptadenia viridiflora , Hyptis suaveolens and Astronium graveolens against M. incognita were evaluated, but only P. viridiflora oil showed toxicity toward M. incognita. Benzaldehyde was its main component according to GC-MS analysis. In in vitro assays, benzaldehyde (100 and 200 μ g ml−1) and its oxime (400 μ g ml−1) caused a higher rate of M. incognita second-stage juvenile (J2) mortality than the nematicide carbofuran (170 μ g ml−1). Reductions of more than 90% in the number of galls and eggs, even greater than that observed with carbofuran, were observed in the assay where the J2 were placed in solutions of benzaldehyde and its oxime 48 h prior to tomato plant inoculation. Application of benzaldehyde together with M. incognita J2 to the substrate resulted only in a reduction in the number of eggs (42-65%); however, its oxime reduced both the number of galls (43-84%) and eggs (23-89%). Therefore, the P. viridiflora oil, its major component benzaldehyde, and the analogue benzaldehyde oxime are toxic to M. incognita. In two different in vivo assays, benzaldehyde oxime was confirmed as toxic to M. incognita with a greater efficacy than benzaldehyde. [ABSTRACT FROM AUTHOR]

The plant-parasitic nematodes seriously affect the growth of many crops and are responsible for agricultural losses worldwide. The losses range from 8 to 20% of major crops around the world. Root-knot nematode Meloidogyne spp. infect and damage a wide range of important crops particularly vegetables in tropical and subtropical countries. The main way of controlling the plant parasitic nematodes is the use of chemical nematicides. Although the nematicides are quickly effective, they are usually expensive and not available and also cause a lot of risk to humans and inflict injury to the environment. Due to the environmental hazards associated with their application, identifying alternatives for nematode control and developing effective and safe application techniques is urgent strategy for alleviating the nematode induced damage. The biological controls are alternatives eco-friendly agricultural systems and safer for environments and humans and cheaper than chemical control This study was conducted to isolate and estimate the potential of some native rhizobacteria from roots in agriculture soil against root-knot nematode, Meloidogyne incognita J2 to evaluate their efficiency as eco-friendly control alternatives for controlling root- knot nematode M. incognita under laboratory conditions. Nine rhizobacteria were isolated from soil (R1 to R9). The best mortality was recorded by isolate no. R6 (77.55%) followed by isolated no. R2 (75.59%) followed for isolate no. R7 (71.43%) as compared with zero% for the control (water only) after 72h exposure periods. R6, R2, and R7 were identified as Lysinibacillus sphaericus, Bacillus pumilus and Pseudomonas flourescens, respectively based on the analysis of the 16S rRNA gene sequence. The partial 16S rRNA gene sequence of these bacterial isolates were deposited in GenBank under accession numbers of MF000302, MF000303 and MF000304 for the previously mentioned bacterial species. [ABSTRACT FROM AUTHOR]

In recent years, non-chemical control of common species of the root-knot nematodes (Meloidogyne spp.), including soil enrichments by organic matters, animal manures and chemical fertilizers has received considerable attention. In 2014, in an experiment, effects of two levels (10 and 25 mg/kg) of sulfur fertilizers viz. ammonium sulfate, calcium sulfate, potassium sulfate, magnesium sulfate and zinc sulfate, and the levels of 25 and 50 mg/kg of elemental sulfur on the activity of the root-knot nematode M. incognita , in pasteurized soil were studied in greenhouse. Seedlings of cucumber cv. Negin at three or four-leaf stages were inoculated with two eggs or second stage juveniles of the nematode/g of soil. The results of two trials showed that magnesium sulfate 10 mg/kg caused 179% increase in the yield on average. The highest reduction was recorded in the number of eggs/g of root and reproductive factor in 25 mg/kg level of calcium sulfate with 71.6% and 58.6%, decrease followed by 25 mg/kg sulfur with 69.1% and 57.0% decrease respectively. The treatment of 50 mg/kg of sulfur was also in the next rank. [ABSTRACT FROM AUTHOR]

In vitro sensitivity of different populations of Meloidogyne javanica and M. incognita to the nematicides Salibro™ and Vydate® Keywords: nematode control; root-knot nematodes; sulfonamide nematicide Salibro™ nematicide is a novel sulfonamide nematicide containing the active substance (a.s.) Nematode control, root-knot nematodes, sulfonamide nematicide. [Extracted from the article]

Organic acids released during the decomposition of organic soil amendments have been used in crop fields as benign chemicals to control phytopathogens. However, the use of organic acids against root-knot nematodes (RKNs, Meloidogyne spp.) has not been recommended in practice, owing to their short retention time in the soil. In this study, we tested the nematicidal activity of organic acids including maleic, fumaric, acetic, acrylic, caprylic, oxalic, and formic acids, as well as copper sulfate against Meloidogyne incognita. Maleic acid showed the strongest nematicidal activity with induction of 100% second-stage juvenile (J2) mortality and 70.47% hatching inhibition at a concentration of 0.37 mmol/L. In addition, the combination of maleic acid and copper sulfate was revealed to have an additive effect in J2 mortality. Application of a wettable powder-type formulation of a mixture of maleic acid and copper sulfate (MIX-WP30) reduced RKN disease on tomato by 51.72% in a pot experiment, suppressed gall formation on melon and decreased nematode population density in the soil. Under field conditions, the efficacy of MIX-WP30 (46.73%) was comparable with that of the commercial nematicide fosthiazate (48.38%). This study identified the effectiveness of MIX-WP30 against RKNs, and demonstrated that there was an in vivo synergistic effect of MIX-WP30. Based on its nematicidal activity, MIX-WP30 could be used as an effective nematicide for RKN management. Unlabelled Image • Maleic acid showed potent nematicidal activity against root-knot nematode (RKN). • Maleic acid and CuSO 4 showed synergistic suppression effects on tomato RKN disease. • The mixture of two chemicals effectively suppressed melon RKN disease in a field. [ABSTRACT FROM AUTHOR]

In vitro sensitivity of different populations of Meloidogyne javanica and M. incognita to the nematicides Salibro™ and Vydate® Keywords: nematode control; root-knot nematodes; sulfonamide nematicide Salibro™ nematicide is a novel sulfonamide nematicide containing the active substance (a.s.) Nematode control, root-knot nematodes, sulfonamide nematicide. [Extracted from the article]

The nematicidal activity of fluensulfone against Xiphinema index and Longidorus vineacola was compared to that of organophosphate and carbamate nematicides. The number of X. index recovered via Baermann funnel from infested soil treated with fenamiphos or cadusafos at 2.0 and 4.0 mg l−1 soil was higher than that recovered from untreated infested soil. The number of recovered X. index after fluensulfone treatment at these concentrations reflected the same level of that recovered from the control soil; however, a high percentage of the nematodes were immobilized after extraction. In experiments using fig plants in pots, the X. index population was much lower after treatment with fluensulfone vs. fenamiphos. Moreover, the nematode control efficacy of fluensulfone against X. index was much higher by pre-planting vs. post-planting application. Treatment of L. vineacola-infested soil with fluensulfone at 2.0 and 4.0 mg l−1 soil slightly reduced the number of recovered nematodes in one of two trials, whereas fenamiphos and cadusafos did not reduce, and sometimes even increased the number of nematodes recovered from the soil. The nematode control efficacy of fluensulfone against L. vineacola was much higher than that of fenamiphos or oxamyl in pots with pepper plants. Again, pre-planting application of fluensulfone was more effective at reducing the L. vineacola population than post-planting application. The results suggest that fluensulfone can effectively control Xiphinema and Longidorus in the field, especially by pre-planting treatment. [ABSTRACT FROM AUTHOR]

Summary: Soybean, Glycine max , is a relatively new crop in Europe gaining increasing interest for its potential to fix atmospheric nitrogen and thus increase sustainability of modern agricultural production systems. Under temperate conditions, root-lesion nematodes (Pratylenchus spp.) are one of the most prominent plant-parasitic nematode taxa of economic concern in soybean. Here, we investigated the susceptibility of soybean cultivars towards naturally occurring populations of Pratylenchus spp. and their effects on soybean yield. At the site Bundesallee the cultivars 'Abelina', 'Primus' and 'Taifun3' supported the highest infestation and multiplication of a mixed population of P. neglectus and P. crenatus , while 'Sultana' and 'Solena' were least susceptible. At the field site Groß Lüsewitz, 'Primus' and 'Merlin' cultivars were significantly more susceptible to P. neglectus than 'Sultana'. Soybean yield was reduced by high initial densities of Pratylenchus spp. Results are expected to contribute to a better nematode management. [ABSTRACT FROM AUTHOR]

Summary: Commercially available sorghum cultivars were tested for resistance to Meloidogyne incognita in order to select cultivars that combine fodder production with M. incognita population management. Initially in a pot test with 12 sorghum cultivars, 'Kyushuko 3 go', a sorghum hybrid, supported very low M. incognita reproduction approximately 40 days after inoculation (dai) with 500 second-stage juveniles (J2) pot−1, similar to the resistant green manure 'Tsuchitaro'. Further tests for development of M. incognita in roots (20 dai with 150 J2 (root system)−1) indicated that the resistance of 'Kyushuko 3 go' acts after nematode root penetration. In field tests in 2015 and 2016, 'Kyushuko 3 go' suppressed M. incognita population densities, although some variations in field conditions may influence reproduction of M. incognita on 'Kyushuko 3 go'. These findings demonstrated M. incognita -resistant fodder sorghum cultivars could be a useful alternative to susceptible cultivars for root-knot nematode management. [ABSTRACT FROM AUTHOR]

• Sheep farmers have local knowledge about helminth parasites of sheep in Ethiopia. • Farmers in community-based breeding programs use anthelmintics more frequently. • Sheep producers prefer anthelmintics over other options for control of nematode parasites. • Ethnoveterinary methods are applied in only one community. Gastrointestinal nematodes (GIN) remain one of the main health and production constraints of sheep globally. Considering alternatives to anthelmintics in control of GIN of sheep has become important mainly due to development of anthelmintic resistance. In this study, we used a questionnaire survey in combination with participatory epidemiology methods, ranking and scoring, with the objectives of (1) understanding local sheep disease problems related to GIN in community-based breeding programs (CBBP) in Bonga and Horro of Ethiopia, compared to neighboring communities not involved in CBBP, and (2) assessing current practices and preferences in control of GIN of sheep in both types of communities. The most important disease conditions of sheep in Bonga CBBP with weighed ranks of 1 to 3 were coenurosis, diarrhea and coughing. The corresponding sheep disease conditions in Horro CBBP were coughing, diarrhea and bottle jaw. Diarrhea and bottle jaw presumably are related to gastrointestinal nematodes. Ethnoveterinary medicinal plants are widely used in Bonga while the knowledge is at risk of loss in Horro. Respondents in non CBBP and CBBP communities did not differ (p > 0.05) regarding most of the plant species used frequently in control of GIN in Bonga. There was significant difference (p < 0.001) in frequency of anthelmintic use between CBBP and non CBBP communities for each of the two locations, Bonga and Horro. In Horro, CBBP farmers considered anthelmintics as more sustainable GIN control option than non CBBP farmers (p < 0.001). This can be attributed to lack of awareness pertinent to development of anthelmintic resistance. In conclusion, local knowledge, practices and preferences of farmers should be considered when designing and implementing control programs for gastrointestinal nematodes. [ABSTRACT FROM AUTHOR]

Sustainable production of tomato (Solanum lycopersicum L.) under high tunnels is threatened by bacterial wilt (caused by Ralstonia solanacearum) and root-knot nematode (Meloidogyne spp.). Knowledge was generated about the concomitant occurrence of these diseases from January to September 2016, and knowledge and experience of farmers about practices to control them were investigated. The study involved a survey during which 32 farmer groups in 6 subcounties of Kiambu County, Kenya, were interviewed. About 78.1% of high tunnels were in use for 1–2 years and 62.5% of farmers taking part in the study could identify symptoms caused by both causal organisms, which resulted in crop loss of 50%–100%. Seventy-one percent of respondents had positive feelings about high tunnel tomato production. About 82.6% had the soil in which they produced tomato in the tunnels analyzed for nutrition and presence of pathologens, but the majority (71.7%) never followed recommendations on how to amend their soils nutritionally and against the major soil-borne diseases. These findings indicate that more research and information are required so that farmers can optimize high tunnel production of tomato under tropical conditions. [ABSTRACT FROM AUTHOR]