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1
d’ ERRICO, GIADA, SILVIA LANDI, ELISA ANGELINI, et al. "NEMATOFAUNA PRESENT IN THE VENETIAN VINEYARD." Redia 107 (July 31, 2024): 99–105. http://dx.doi.org/10.19263/redia-107.24.15.
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Attacks of plant-parasitic nematodes can seriously affect grapevine yield and quality, also due to synergistic damages caused by the co-presence of nematodes and viruses. A survey was carried out in vineyards from a D.O.C.G. area of Veneto region, Italy, in order to better understand the relationship between grapevine plants and presence of phytonematodes. Most concerns were raised by detection of species as Mesocriconema xenoplax and Xiphinema index, this latter as the vector of grapevine fanleaf virus (GFLV), the most economically important nepovirus in vineyards. Some individuals of Pratylenchus vulnus were also found. Numerous predaceous nematodes as Mononchida were found within several soil samples. Mononchida play an important role in contrasting the spread of other nematodes, including plant-parasitic nematodes. During the survey, other non-plant-parasitic nematodes as Dorylaimina and Rhabditida were homogeneusly distribuited among samples. Key Words: grapevine, Grapevine fanleaf virus (GFLV), nematodes, trophic groups, Xiphinema index.
2
Mateille, Thierry, Nicole Gautier, Domitien Debouzie, and Patrice Cadet. "Étude synthétique des réactions induites par les nématodes phytoparasites sur le bananier Musa acuminata (groupe AAA) : hiérarchisation des paramètres adaptés à la sélection variétale." Canadian Journal of Botany 73, no. 12 (1995): 2006–18. http://dx.doi.org/10.1139/b95-215.
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The susceptibility of bananas to phytoparasitic nematodes, the damages caused by nematodes, and the plant defense reactions can be evaluated respectively by the multiplication rate of parasites, the plant growth and metabolism, and the modifications of the secondary metabolism. The comparison, through multivariate analyses, of these four groups of parameters between two banana cultivars (Poyo and Gros Michel), differently susceptible to nematodes, helps to hierarchize the importance of these groups. So, the variables associated with shoot and root growth and the variables associated with plant physiology (photosynthesis, carbon metabolism, nitrogen and mineral absorption) are quite bad parameters because they evolve anarchically with the initial nematode population pressure. On the opposite, the final nematode population pressure and the variables associated with host defense reactions (secondary metabolism) are more reliable because they give more homogeneous results. It is then possible to assess the usefulness of the parameters describing banana susceptibility to nematodes and to give reliable criteria to geneticians for nematode resistance breeding programs. Key words: banana, defense reactions, phytoparasitic nematodes, resistance, tolerance, cultivar behaviour. [Traduit par la rédaction]
3
Kerry, B. R. "Ecological considerations for the use of the nematophagous fungus, Verticillium chlamydosporium, to control plant parasitic nematodes." Canadian Journal of Botany 73, S1 (1995): 65–70. http://dx.doi.org/10.1139/b95-226.
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The nematophagous fungus, Verticillium chlamydosporium, has considerable potential as a biological control agent for root-knot nematodes on a range of crops. The fungus is a general facultative parasite that attacks the eggs of several nematode species. The biology of the fungus is reviewed and the need for a detailed understanding of its ecology for its rational use as a biological control agent is highlighted. Isolates of the fungus must colonize the rhizosphere to be effective control agents. Plants differ in their ability to support the fungus and greatest control is achieved on those cultivars that support abundant growth of the fungus but produce only limited galling in response to nematode attack. On such plants, most eggs produced by nematodes are exposed to parasitism by this nematophagous fungus in the rhizosphere. Key words: biological control, nematophagous fungi, root-knot nematodes, Verticillium chlamydosporium.
4
Jaffee, B. A. "Population biology and biological control of nematodes." Canadian Journal of Microbiology 38, no. 5 (1992): 359–64. http://dx.doi.org/10.1139/m92-061.
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We studied the population biology of the nematophagous fungus Hirsutella rhossiliensis to understand its potential as a biological control agent. Because the fungus is an infectious and transmissible parasite, we framed our study within an epidemiological context. Field observations, theory, and experiments demonstrated that (i) parasitism of nematodes by H. rhossiliensis is dependent on nematode density, (ii) local populations of the fungus will go extinct unless supplied with some minimum number of nematodes (the host threshold density), and (iii) natural epidemics of this fungus in populations of nematodes develop slowly and only after long periods of high host density. Additional in-depth research on population biology is needed to explain other biological control systems and to guide future research. The most effective research will combine field observation, theory, and experimentation. Key words: density-dependent parasitism, host-parasite dynamics, modeling, nematophagous fungi.
5
EL KHOURY, YARA, CARLO SALVEMINI, EUSTACHIO TARASCO, and GIUSEPPE CRINGOLI. "NEW EXTRACTION METHOD OF ENTOMOPATHOGENIC NEMATODES USING THE BASIC FLOTAC AND THE MINI-FLOTAC TECHNIQUES." Redia 107 (February 1, 2024): 3–7. http://dx.doi.org/10.19263/redia-107.24.01.
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The FLOTAC basic technique is a recognised method used mainly in the veterinary field to extract parasites from the faeces of animals found in the stomach and intestine. This study is the first application of the FLOTAC and Mini-FLOTAC techniques to extract infective juveniles of entomopathogenic nematodes from infested Galleria mellonella. The EPN used for this purpose was an endemic Italian nematode belonging to the Rhabitidae family Steinernema carpocapsae. Galleria mellonella larvae were infected and extraction was performed a few days after infection using both techniques. A comparison was then made between the two methods. The results showed that infective juveniles could be extracted from the infected larva as early as three days after infection. The difference between the FLOTAC basic technique and the Mini-FLOTAC technique was not significant in the extraction of entomopathogenic nematodes. Due to its sensitivity and operating easiness the Mini-FLOTAC technique is a promising method for the extraction of entomopathogenic nematodes. It allows faster extraction of nematodes from the inhabited soil and insect host than the conventional White trap method. Key Words: Microbial biocontrol, Entomopathogenic nematodes, Nematode extraction, FLOTAC, Mini-FLOTAC
6
Riga, E., J. Whistlecraft, and J. Potter. "Potential of controlling insect pests of corn using entomopathogenic nematodes." Canadian Journal of Plant Science 81, no. 4 (2001): 783–87. http://dx.doi.org/10.4141/p00-116.
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A series of experiments was performed in the laboratory and in the greenhouse to assess the efficacy of the entomopathogenic nematodes, Steinernema glaseri or S. feltiae in decreasing the numbers of European corn borer, fall armyworm, western corn rootworm and the seedcorn maggot in corn. Both nematode species effectively controlled the four insect pest species. During greenhouse experiments, the number of plants protected with entomopathogenic nematodes against these insect pests was significantly higher than in the untreated controls. Similar results were obtained in a microplot study of corn infected with the European corn borer, the western corn rootworm and the seedcorn maggot. The application of a single nematode species against several insect pests has economic advantages. In addition, both S. glaseri and S. feltiae overwintered and survived in the field until the next growing season. Key words: Entomopathogenic nematodes, sweet corn, European corn borer, fall armyworm, seedcorn maggot, western corn rootworm
7
Vrain, Thierry C. "Pathogenicity of Pratylenchus penetrans to American Ginseng (Panax quinquefolium) and to Kiwi (Actinidia chinensis)." Canadian Journal of Plant Science 73, no. 3 (1993): 907–12. http://dx.doi.org/10.4141/cjps93-119.
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The host status and susceptibility of American ginseng and kiwi to the root-lesion nematode were studied in greenhouse experiments. Two-year-old ginseng roots were transplanted into 2.5-L. pots containing 0, 2000, 6000, 10 000, or 15 000 nematodes. After 100 d tap root growth was not significantly affected at the low inoculum densities but it decreased by 32% at the highest inoculum density. The nematodes did not multiply in ginseng roots. One-year-old Kiwi roots were transplanted into 2.5-L. pots containing 0, 2000, 5000, 10 000, and 15 000 nematodes. After 120 d the weight of kiwi vines and roots grown in nematode-infested soil decreased by 15 and 25%, respectively, when compared to plants grown in nematode-free soil. The nematode population barely maintained itself at the lowest inoculum density and declined at the higher inoculum densities. Key words: Nematode, root-lesion, resistance, host status
8
CAPRIO, ELENA, VINCENZO ESPOSITO, SALVATORE LISBINO, and EDOARDO BATTAGLIA. "EMERGING NEMATOLOGICAL PROBLEMS IN THE CAMPANIA REGION." Redia 107 (July 30, 2024): 83–87. http://dx.doi.org/10.19263/redia-107.24.11.
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During a fifteen-year period of work carried out by the Test facility for the farm acquisition to be used to conduct efficacy trials against nematodes, a survey was carried out on nematological problems occurring in the Campania Region. The investigations has shown that the genus Meloidogyne spp., in particular the species M. incognita, is the most widespread and harmful trophic group. These nematodes are found in particular on horticultural plants in the sandy soils of the coastal areas and especially under protected conditions. Infestations of the cyst nematodes Globodera rostochiensis and G. pallida on potato in the neighbouring Caserta and Neapolitan areas, H. goettingiana on leguminous plants, especially peas, and H. daverti on carnation in the Vesuvian foothills are also common. In the Nocerino-Sarnese countryside, infestations by the stem and bulb nematode, Ditylenchus dipsaci, on onions are still severe. On fruit trees are common Mesocriconema xenoplax on actinidia, Meloidogyne incognita and M. hapla on peach trees and Tylenchulus semipenetrans on citrus fruits. Among the virus transmitting nematodes, Xiphinema diversicaudatum is very harmful to peach trees in Terra di Lavoro, in the Carinola (Caserta) area, and X. index to grapevines in the Benevento and Avellino areas. Key Words: phytoparasitic nematodes, crops, distribution, damage.
9
RUIU, LUCA, XINGYUE LI, and EUSTACHIO TARASCO. "ENTOMOPATHOGENIC NEMATODES ASSOCIATION WITH SOIL- DWELLING BACTERIA: THE CASE OF STEINERNEMA FELTIAE." Redia 107 (July 30, 2024): 89–92. http://dx.doi.org/10.19263/redia-107.24.12.
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The symbiosis of entomopathogenic nematodes (EPNs) with bacteria in the genera Photorhabdus and Xenorhabdus is well known. However, other soil-dwelling bacteria can occasionally be isolated from EPNs collected from diseased larvae. Accordingly, through several studies, we have detected the presence of diverse bacterial species including isolates of Pseudomonas protegens and Serratia spp., in the body of different strains of the entomopathogenic nematode Steinernema feltiae. After documenting the presence of such bacteria inside the nematodes, both nematodes and EPN-associated bacteria were cultured, and bioassays were conducted to determine their potential against different insect targets. An isolate of P. protegens caused over 60% and 90% mortality of house fly and corn earworm larvae, respectively. These insecticidal effects were dose-dependent. The presence of the bacterium confers virulence to the nematode. According to our studies, it appears that these non-core bacteria can establish occasional or stable associations with S. feltiae. Key Words: Biological control, EPN, bacteria, symbiosis, Pseudomonas, soil, bioinsecticide.
10
Saddiqi, Hafiz Abubakar, Abdul Jabbar, Zafar Iqbal, Wasim Babar, Zia-ud-Din Sindhu, and Rao Zahid Abbas. "Comparitive efficacy of five anthelmintics against trichostrongylid nematodes in sheep." Canadian Journal of Animal Science 86, no. 4 (2006): 471–77. http://dx.doi.org/10.4141/a06-036.
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The efficacy of levamisole, ivermectin and three different preparations of oxfendazole, applied at the recommended rate, were evaluated in flocks of sheep kept at two farms in Thal desert, Pakistan. Sixty animals on each farm were selected randomly on the basis of their weight and egg count of more than 150 eggs per gram of faeces. Three preparations of oxfendazole (fendamex, oxazole, syatamex), levamisole and ivermectin were given to five groups while one untreated group was kept as control. Faecal egg counts, faecal egg count reduction test, postmortem worm count and copro-culture were performed to assess the efficacy of selected anthelmintics. Levamisole and ivermectin preparations reduced (P ≤ 0.05) prevalent species of gastrointestinal nematodes in both flocks. Oxfendazole preparations exhibited low efficacy and some gastrointestinal nematodes (Haemonchus and Trichostrongylus) were suspected for resistance against these preparations, with resistance more pronounced in oxazole followed by systamex and fendamex. It was concluded that all oxfendazole preparations had low efficacy with suspicion for anthelmintic resistance while levamisole and ivermectin had reasonable effectiveness against prevalent gastrointestinal nematodes of sheep kept in Thal desert, Pakistan. Key words: Anthelmintic, resistance, gastrointestinal nematodes, sheep, Pakistan
11
Saikawa, Masatoshi, Masami Oguchi, and Rafael F. Castañeda Ruiz. "Electron microscopy of two nematode-destroying fungi, Meristacrum asterospermum and Zygnemomyces echinulatus (Meristacraceae, Entomophthorales)." Canadian Journal of Botany 75, no. 5 (1997): 762–68. http://dx.doi.org/10.1139/b97-086.
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Infection of nematodes by Meristacrum asterospermum and Zygnemomyces echinulatus was initiated by conidia adhering to the nematode's cuticle. Each conidium developed an infection peg to penetrate the nematode after adhesion. In M. asterospermum, an infection peg just under the penetration was found in ultrathin sections, in which the peg's cell wall was broken into several lobes that were covered entirely with an amorphous mass of electron-opaque substance. Septa formed in the apical portion of aerial conidiophore under conidiation. The septal wall was nonperforate and often contained electron-opaque inclusions. Vegetative hyphae of Z. echinulatus had typical bifurcate septa, but septa at both ends of the pedicel of conidia were often slightly deformed. Key words: infection of nematodes, Meristacrum asterospermum, septum, Zygnemomyces echinulatus.
12
Barron, G. L. "A new species of Dwayaangam parasitic on eggs of rotifers and nematodes." Canadian Journal of Botany 69, no. 7 (1991): 1402–6. http://dx.doi.org/10.1139/b91-180.
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Dwayaangam heterospora is described as a new Hyphomycete attacking the eggs of rotifers and nematodes. The fungus attaches to the eggshell by an appressorium-like swelling. After penetration a postinfection bulb is produced from which haustorium-like assimilative hyphae develop and consume the contents of the egg. The fungus produces several morphologically different types of conidia from inconspicuous conidiogenous cells. The conidia are solitary, hyaline and septate and are either scolecospores or staurospores. Key words: egg parasite, rotifers, Dwayaangam, Triposporina, aquatic hyphomycetes.
13
Forge, T. A., and S. W. Simard. "Short-term effects of nitrogen and phosphorus fertilizers on nitrogen mineralization and trophic structure of the soil ecosystem in forest clearcuts in the southern interior of British Columbia." Canadian Journal of Soil Science 81, no. 1 (2001): 11–20. http://dx.doi.org/10.4141/s00-018.
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Ammonium sulphate and an ammonium sulphate-ammonium phosphate mixture were applied at 200 kg N ha-1 and 200 kg P ha-1 at three clearcut sites within the Interior Cedar-Hemlock biogeoclimatic zone in southern British Columbia. N mineralised under aerobic and anaerobic conditions, nitrification, biomasses of fungi and bacteria,the abundance of protozoa, and the trophic structure of nematode communities were studied at 4, 12, 16, and 28 mo after fertilisation. Nitrogen mineralised under aerobic conditions was greater in fertilised soil than in non-fertilised soil at 4 and 16 mo after fertiliser applications. Nitrification also increased after fertilisation. Fertilisation did not affect bacterial or fungal biomasses, but did increase the ratio of bacterial biomass/fungal biomass, the abundance of bacterivorous nematodes, and the ratio of bacterivorous nematodes/fungivorous nematodes. Thus, the fertiliser-induced increase in N mineralization appears to have been the result of increased bacterial decomposition and flow of carbon and nitrogen through bacteria-bacterivore channels of the soil food web. Key words: N mineralization, fertilisation, microbial biomass, microfauna, nematode ecology
14
CONZA, VALERIO, ALESSANDRO GALLO, and ROBERTO CONZA. "THE POTENTIAL OF TEQUIL, A PLANT EXTRACT BASED ON QUILLAJA SAPONARIA, IN SUSTAINABLE AGRICULTURE." Redia 107 (July 30, 2024): 77–81. http://dx.doi.org/10.19263/redia-107.24.10.
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More attention is being given to researches of eco-sustainable solutions to be implemented in agriculture, particularly in the presence of plant parasitic nematodes, whose damages have significant global importance. Unsustainable practices, such as fumigation and monoculture, have led to depletion of biodiversity, allowing harmful trophic groups (bacteria, fungi, and nematodes) to prevail, and their negative synergistic action further exacerbating yield losses. Considering the notable and progressive restriction of usable molecules, nematode control strategies must necessarily consider the appropriate integration of methods. The main objective of control is to limit pathogen populations below the damage threshold, rather than aiming at their eradication as mistakenly pursued in the past. This goal can be achieved with the help of solutions that promote plant development through biostimulation of root systems, which are often affected by various organisms in the biosphere. Tequil, through its well-documented synergy of saponins, tannins, and polyphenols, produces invigorating, biostimulating, and strengthening effects on the root system. Indeed, in vitro tests and field trials have highlighted Tequil’s appreciable activity in containing trophic groups, particularly root-knot nematodes of the Meloidogyne genus. Therefore, its use could indirectly contribute to nematode control and limit yield losses. Key Words: Quillaja saponaria, nematodes, bio stimulation, biocontrol, abiotic stresses resistance.
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Olthof, Th H. A., and M. S. Wolynetz. "Pratylenchus penetrans and P. neglectus in tubers of potato (Solanum tuberosum) in Ontario." Canadian Journal of Plant Science 71, no. 4 (1991): 1251–56. http://dx.doi.org/10.4141/cjps91-173.
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Root-lesion nematodes (Pratylenchus penetrans) were extracted from peels of potato tubers (Solanum tuberosum 'Russet Burbank'). The average number of P. penetrans recovered over a 2-wk period in a mist chamber from four batches of tubers, stored for 3–18 wk at 7 °C in a cold room, ranged from 11 to 1925 nematodes tuber−1. An average of 374 Pratylenchus neglectus tuber−1 were recovered from the peels of potato Norchip, grown in soil containing on average 4370 nematodes kg−1 of soil at harvest, and stored for 19 wk at 7 °C. P. penetrans and P. neglectus were recovered only from the outer layer of potato tubers; none was found in the inner core. Planting halves of tubers containing an average of 1925 P. penetrans tuber−1 into nematode-free soil resulted in soil population densities of 2225 P. penetrans kg−1 of soil and root population densities of 884 nematodes root system−1 after 8 wk in the greenhouse. Although many, if not most, potato fields in southern Ontario are already infested by P. penetrans, these studies have shown that stored, infested tubers can initiate a new infestation. Key words: Peel, potato tuber, Pratylenchus neglectus, Pratylenchus penetrans, root-lesion nematode, Solanum tuberosum
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Forge, T. A., and S. W. Simard. "Trophic structure of nematode communities, microbial biomass, and nitrogen mineralization in soils of forests and clearcuts in the southern interior of British Columbia." Canadian Journal of Soil Science 80, no. 3 (2000): 401–10. http://dx.doi.org/10.4141/s99-112.
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The trophic structure of nematode communities, lengths of fungal hyphae, and gross populations of protozoa and bacteria were compared between clearcuts and adjacent forests at three sites in the southern interior of British Columbia in 1996, 1997, and 1998. Total C and N, mineralizable N (anaerobic incubation), and N mineralised during aerobic incubations, were determined from the same soil samples used for biological assays. Net N mineralization did not differ between clearcuts and forests in 1997; in 1998 net N mineralization in the organic horizon was four times greater for forests than for clearcuts. Hyphal lengths and total microbial biomass were greater in forest soil than in clearcut soil. Bacterial abundance was greater in forest soil than in clearcut soil in 1996 only. The abundance of protozoa did not differ between clearcuts and forests. Fungivorous, omnivorous, and predacious nematodes were less abundant in clearcut soil than in forest soil. Bacterivorous nematodes were more abundant in the mineral soil of clearcuts than in forests in 1996, but did not differ between clearcuts and forests in any other combination of year and horizon. Net N mineralization was correlated with the ratio of bacterial biomass/fungal biomass (r = 0.72, 12 degrees of freedom), as well as the abundance of amoebae (r = 0.83), total nematodes (r = 0.80), bacterivorous nematodes (r = 0.74), and fungivorous nematodes (r = 0.83). Key words: Microfauna, nematode ecology, microbial biomass, clearcut harvesting, nitrogen mineralization
17
Mogeni, IH, and N. Bitange. "Abundance, diversity and distribution of soil nematodes in Kangaita and Weru tea catchments of Kirinyaga and Tharaka Nithi counties, Kenya." African Journal of Food, Agriculture, Nutrition and Development 24, no. 2 (2024): 25525–36. http://dx.doi.org/10.18697/ajfand.127.23950.
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Nematodes are the most abundant animals on earth and play essential roles in ecosystem functioning hence their abundance and diversity affect soil health. Nematodes have been reported in tea fields in some parts of Kenya and previous studies indicate that they may be a cause for the decline of tea population in some tea fields in Kenya. Nematodes of Moloidogyne spp have also been reported to be responsible for death of tea plants in nursery conditions. A survey was carried out in Weru and Kangaita tea factories catchment areas in Tharaka Nithi and Kirinyaga counties respectively. The survey aimed to determine the abundance and diversity of nematodes in small holder tea farms. Kangaita represented the high elevation site while Weru represented the low elevation site. Soil samples were collected from smallholder tea farms from which nematodes were extracted, identified based on their morphological characteristics, and classified according to their feeding habits then quantified using standard protocols. Nematodes from 23 genera were recovered in the two study sites representing all the five feeding groups: plant feeders, fungal feeders, bacterial feeders, omnivores, and predatory nematodes. Of the 23 genera, 11 were plant feeders, 6 bacterial feeders, 3 fungal feeders 2 omnivores and 1 predatory nematode. Kangaita, being a high elevation site reported higher population density in most genera reported than Weru which is a low elevation site. This is a departure from most studies that have reported higher nematode population densities in low altitudes. This can be attributed to differences in climatic and soil conditions in the two study sites in the same season. Kangaita was cooler with deep, well-ventilated, and loose soils while Weru was hotter with mostly compacted, shallow, and poorer soils in the tea farms. There is need for further research on the effect of elevation and farming practices on the distribution, abundance, and diversity of nematodes in tea fields. Key words: Nematodes, abundance, soil health, tea fields, elevation, diversity, feeding group
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McKeown, Alan W., R. F. Cerkauskas, John W. Potter, and L. van Driel. "Long-term evaluation of cover crop and strip-tillage on tomato yield, foliar diseases and nematode populations." Canadian Journal of Plant Science 78, no. 2 (1998): 341–48. http://dx.doi.org/10.4141/p97-090.
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A 6-yr (1987–1992) experiment, continuous on the same site, evaluated potential problems for yield, nematodes and diseases with tomatoes (Lycopersicon esculentum Mill.) grown in a strip-till system. Treatments consisted of conventional tillage (CT) and strip tillage (ST), rye (Secale cereale L.), wheat (Triticum aestivum L.) and perennial ryegrass (Lolium perenne L.) cover crops and a 2-yr rye-tomato rotation. Results of the first 5 yr indicated a decrease in tomato yield over time for both tillage treatments and cover crops. However, yield rebounded overall for treatments in 1992 with the highest yield in the rye-tomato rotation. We suspect this was a result of high populations of root-knot nematodes which collapsed over the winter of 1991/1992. Tomato yields were lower following wheat and perennial ryegrass than rye. In only 1 yr out of 6, strip-tillage reduced yield compared with conventional tillage. Bacterial speck/spot symptoms on foliage, although minor, were significantly greater in ST than in CT plots during the last 3 yr. No major trends in incidence and severity of bacterial and fungal diseases and of disorders of fruit were evident during the 5-yr period and neither fruit yield nor quality were significantly affected by these factors. Root-knot nematodes (Meloidogyne hapla Chitwood) were numerically less in the rye-tomato rotation than in other treatments; both root-knot and root lesion nematodes (Pratylenchus penetrans [Cobb]) tended to be less numerous under CT than under ST. Strip-tillage is feasible for machine harvest processing tomatoes. However, we are concerned about the tendency of tomatoes grown under reduced tillage to have lower yields than those grown under conventional tillage. More work is required on the interactions of cultivars, cover crops and nematodes in soil conservation systems. Key words: Tomato, bacterial speck/spot, foliar diseases, root-knot nematodes, root lesion nematodes, tillage
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Potter, J. W., and A. W. McKeown. "Nematode biodiversity in Canadian agricultural soils." Canadian Journal of Soil Science 83, Special Issue (2003): 289–302. http://dx.doi.org/10.4141/s01-064.
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The biodiversity of soil-inhabiting nematodes in Canada is incompletely known, as large areas of Canada’s landmass have not been surveyed for nematode fauna. Nematodes considered as indigenous are generally well adapted to a variety of ecological niches and climatic zones. Much of the available information is based on agricultural ecosystems and agricultural species, and thus is biased toward conditions in disturbed ecosystems and away from “primeval” ecology. Introduced nematode species are frequently quite pathogenic, even to exotic host plants from the same geographic point of origin. Estimates of crop loss due to single species infestations of pathogenic nematodes and the costs of nematode control using chemicals are reasonably well known, averaging about 10% of crop value, but ranging to 100% depending on the situation; the cost of damage by multiple-species infestations is less defined. Nematode-suppressive mechanisms are understood in only a few plant species; sulfur appears to be important as a constituent of active compounds in suppressive plants of agricultural origin. Similarly, some native plants are equally adapted with allelopathic chemicals that suppress nematodes. Management of nematode populations in agricultural soils by integrated crop management methods is at an early stage, requiring research to quantify effects of nematode-suppressive plants and soil amendments containing nitrogen. An integrated program could include nematode-suppressive plants, appropriate soil amendments, and the promotion of microbial antagonists. Different mathematical methods may be required to analyze and explain multi-factor nematode control systems. Less-toxic management systems could benefit the soil-inhabiting nematodes that predate arthropod soil pests. Further research on soil-borne nematodes may demonstrate the value of nematodes as indicators of agroecosystem health and environmental pollutants. Key words: Biocontrol, biodiversity, nematode distribution, nematode management, soil ecology
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Panjerrino, Yoshua Gdemakarti, Bainah Sari Dewi, and I. Gede Swibawa. "Diversity of Soil Nematode in Utilization Block Integrated Educational Conservation Forest, Wan Abdul Rachman Great Forest Park." Jurnal Sylva Lestari 7, no. 2 (2019): 214. http://dx.doi.org/10.23960/jsl27214-224.
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Change of land forest in Wan Abdul Rachman Forest Park became agroforestry, affect of cover condition and decrease the content of soil matter. Nematode was one of the soils biotas that can be used as an indicator of change in the soil status. The aim of study is to know the community and diversity of nematodes on the Utilization Block, Integrated Educational Conservation Forest, Wan Abdul Rachman Great Forest Park. The research was conducted in April to May 2018. The soil samples were taken on arboretum one, arboretum two, arboretum three and arboretum four in Integrated Educational Conservation Forest, Wan Abdul Rachman Great Forest Park. Nematode observations were conducted in the Plant Pests Laboratory, Faculty of Agriculture, University of Lampung. Nematodes was identified to genus level based on morphological traits. The analysis used were including the index of diversity, dominance and similarities between genus arboretum. The results showed that there were 30 genus of nematode consists of 19 plant parasitic nematode genera, six nematoda bacterial-feeding, three nematode fungal-feeding and two predator nematodes. The dominant nematode genera were Criconomella, Helycotylenchulus and Rotylenchulus. The abundance of nematodes ranges from 171-617 individuals/300cm3 soil. The diversity of soil nematodes based on the Shannon-Wienner index ranges from 2,47 – 2,80. The Shannon-Whienner Index criteria were classified as moderate. The Simpson Index ranges from 0,89 – 0,93. The highest similarity index genus in arboretum three and four with a value of 0,81 and the lowest in arboretum two and three which is 0,54. Key words: nematodes community, Integrated Educational Conservation Forest, Wan Abdul Rachman Great Forest Park
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Effiong, M. U., and N. E. Obot. "Helminth parasites of cultured Clarias gariepinus and Tilapia zillii in Uyo, Akwa Ibom State, Nigeria." Tropical Freshwater Biology 29, no. 2 (2021): 87–94. http://dx.doi.org/10.4314/tfb.v29i2.7.
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The study examined helminth parasites of cultured Clarias gariepinus and Tilapia zillii in Uyo, Akwa Ibom State. A total of 60 fish samples (30 each of C.gariepinus and T. zillii) were subjected to parasitological examinations. Results revealed a total of 47(78.33%) fishes infected with various species of parasites: Nematodes (Camallanus polypteri, Paracamallanus cyathopharynx, and Procamallanus laevionchus), Cestodes (Polyonchobothrium torulosus and P. clariae) and Trematodes (Dactylogyrus extensus and Glossiduim pedatum) in decreasing order of abundance. Out of the 60 fish samples examined, 47 were infected with 219 parasites: 142(64.84%) nematodes, 40(18.26%) cestodes and 37(16.89%) trematodes. A total of 159(72.60%) parasites were recovered from C. gariepinus out of which 103(64.78%) were nematodes, 19(18.45%) were cestodes and 37(35.92%) were trematodes. While 60(27.40%) parasites were recovered from T. zilli, of which 39(65.00%) were nematodes and 21(35.00%) cestodes. No trematode was observed in the tilapia. The overall prevalence of parasitic infection was 78.33%. The results of chi square analysis showed that females of both species had significantly higher (P<0.05) prevalence of infection 27(84.4%) than males 20(71.4%). Also, C. gariepinus had higher infection rate of 25(83.33%) when compared to 22(73.33%) recorded in T. zillii.
 Key words: fish parasites, aquaculture, prevalence, C. gariepinus, T. zillii
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Stiller-Reeve, Mathew, Erling Rosnes, Mari Eiliertsen, Sofia Ramalho, Victor Poddevin, and Giuliana Panieri. "Life from bad smells." Septentrio Educational, no. 1 (April 28, 2023): 27–33. http://dx.doi.org/10.7557/8.7049.
Full textAbstract:

 
 
 
 Focus:
 To understand that hydrogen sulphide indicates that there is life at the bottom of the deep-sea.
 Learning objectives:
 With this activity, we create a nasty smell similar to hydrogen sulphide from rotting organic matter. We use that smell as a foundation for a discussion/lesson on interesting life, animals and food webs from the deep sea floor.
 Key words:
 Deep-sea, hydrogen sulphide, chemosynthesis, nematodes, tube worms, food webs.
 
 
 
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Dong, Daofeng, Yun-Feng Chen, Yosef Steinberger, and Zhi-Ping Cao. "Effects of different soil management practices on soil free-living nematode community structure, Eastern China." Canadian Journal of Soil Science 88, no. 1 (2008): 115–27. http://dx.doi.org/10.4141/cjss07014.
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An investigation was conducted in a Shouguang agroecosystem, Shandong Province, Eastern China, in order to determine the long-term (10–15 yr) disturbances of three different agricultural management practices. In this study, the main focus was on free-living soil nematodes, as a tool which will help differentiate between treatments according to their sensitivity to physical, chemical, and biota composition. In this study, three treatments were implemented in each of a total of four investigated sites: greenhouses, conventional farmlands, and fallows. Diversity, maturity (MI) and weight indices were used to assess the nematode community. The results indicated that greenhouses have a lower richness (SR), diversity, modified maturity index (ΣMI), modified maturity index for all nematodes with c-p = 2–5 [ΣMI (2–5)], plant parasite index (PPI), PPI/MI values, and fungi-feeding/bacteria-feeding (F/B) ratio, as well as lower basal index (BI) and channel index (CI) and higher dominance. These results elucidated the difference between the three treatments, where the greenhouses were an enriched disturbed system compared with the other treatments and were dominated by bacterivorous nematodes, the fallows were a relatively infertile and stable system dominated by plant parasites, and the conventional farmlands can be positioned between the above two treatments. Key words: Agricultural management, nematode, disturbance, indices
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Narda, Naheed Sajida Sultana Suad Naheed Iqra Anam Gulmeena Maha Gung Bakshi1 Maria Essa Najma Sabzal Saima Mehar. "EVOLUTIONOF NEMATICIDAL POTENTIAL OF CRUDE EXTRACT OF MEDICINAL PLANTS FROMPAKISTAN FLORA." INDO AMERICAN JOURNAL OF PHARMACEUTICAL SCIENCES o6, no. 02 (2019): 4532–36. https://doi.org/10.5281/zenodo.2579263.
Full textAbstract:
<em>Root knot nematodes are harming various plants which is economically harmful and can lead towards serious food and economics problem. The research was carried out with aim to point out nematicidal potential of Methanolic extract of five selected medicinal plants, Chinopodium album, Withania Coagulans, Saphora mollis, Peganum harmala and Rosamarinus officinalis. Methanolic extract were used for extract preparation. 80% Methanolic solvent was used. All extracts were prepared in SBKWU lab and nematicidal analysisof crude extract of medicinal plants was carried out in NNRC (national nematicidal research center) Karachi. Culture for incognita species obtained from Lycopersicon esculentum (tomato) plant were prepared at 28 <sup>0</sup>C incubation temperature. For nematicidal assay, second javelined stage was utilized. The analysis was carried out with different dose including 1%, 0.5%, 0.25% and 0.125%. Analysis was made with duration of 0.5, 1, 2, 3, 4, 42, 48 and 72 hours. Significant response was observed in Chinopodium album whose response was 100% reduction in nematodes population at 48 and 72 hours of exposure. All dose of this plant extract also showed positive response but among five selected herbal plants, lowest response was found in Saphora mollisMethanolic extract with 21-51.5 % response at even maximum exposure with highest dose. </em> <strong>Key Words: </strong><em>Root-Knot Nematodes, Nematicidal potential, Methanolic Extract, Medicinal Plants, MeloiogyneSpecies.</em>
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EL-KHOURY, YARA, GIUSEPPE BARI, DANIELE CORNARA, MICHELE POLISENO, and EUSTACHIO TARASCO. "SUSCEPTIBILITY OF PHILAENUS SPUMARIUS (RHYNCHOTA, APHROPHORIDAE) TO ENTOMOPATHOGENIC NEMATODES AND FUNGI." Redia 107 (July 31, 2024): 97–98. http://dx.doi.org/10.19263/redia-107.24.14.
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Xylella fastidiosa, the causal agent of the devastating “olive quick decline syndrome”, is a xylem-inhabiting gram-negative bacterium that was introduced into the Apulia region of southern Italy. Xylella fastidiosa caused an epidemic outbreak and catastrophic dieback of olive groves. This pathogen is transmitted exclusively by xylem fluid-feeding sap insects, the main vector being the meadow jumping beetle Philaenus spumarius. The use of microorganisms such as entomopathogenic nematodes and fungi is a well-known biocontrol strategy against agricultural pests. This study aims to evaluate the pathogenicity of two different entomopathogenic fungi (EPF), the commercial Beauveria bassiana strain ATCC74044 (Naturalis®) and Lecanicillium muscarium Ve6 (Mycotal®), and two indigenous strains of EPNs against juveniles of the meadow spittlebug Philaenus spumarius. Monitoring of insect vectors is necessary to prevent the further spread of Xylella fastidiosa in Europe. The rapid spread of Xylella fastidiosa underlines the importance of preventive biocontrol measures against the vector with EPNs and EPF. Key Words: Xylella fastidiosa, insect vector, Philaenus spumarius, entomopathogenic fungi entomopathogenic nematodes
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Lopez-Llorca, L. V., and G. H. Duncan. "Effects of fungal parasites on cereal cyst nematode (Heterodera avenae Woll.) from naturally infested soil—a scanning electron microscopy study." Canadian Journal of Microbiology 37, no. 3 (1991): 218–25. http://dx.doi.org/10.1139/m91-033.
Full textAbstract:
The effects of fungal endoparasites, attacking the eggs of the cereal cyst nematode Heterodera avenae, and details of the infection process were studied by low-temperature scanning electron microscopy. Some female nematodes, even young ones containing no eggs, were colonized by fungi. Spores and hyphae similar to those of Nematophthora gynophila were found in infected specimens. Fungi colonized both roots and nematodes. In early stages of infection, fungi developed within the female nematode between the organs, presumably using the female's body as a food source. In some immature females, the fungi appeared to have destroyed the uterus. In old females, appressoria of Verticillium spp., including V. chlamydosporium, penetrated the eggs they contained and progressively destroyed their contents until the egg shell was filled with hyphae and spores. Only rarely were second-stage juveniles within eggs infected by these fungi. Fungal infection of eggs, which arrests their development at an early stage, therefore occurs predominantly in females rather than in newly formed cysts. Key words: Heterodero avenae, fungal parasites, naturally infested soil, scanning electron microscopy.
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Ishida, Kyoko, and Taizo Hogetsu. "Role of resin canals in the early stages of pine wilt disease caused by the pine wood nematode." Canadian Journal of Botany 75, no. 2 (1997): 346–51. http://dx.doi.org/10.1139/b97-036.
Full textAbstract:
The role of cortical resin canals in the early development of a pine wilt disease in Japanese black pine, Pinus thunbergii, was studied. A part of the bark of a 2 cm long segment from a current-year stem was removed by a tangential cut with a razor blade. Both cortex-exposed segments with cut cortical resin canals (designated as +RC segments) and those without cut resin canals (–RC segments) were obtained by chance. When a virulent nematode isolate (S6-1) was inoculated onto the cut surface, the surface of the +RC segments turned brown 4 d after inoculation, and in some segments this browning occurred more intensely around cortical resin canals. When segments were cut transversely at the middle, the transverse cut surface of the inoculated +RC segments was brown and fragile, but that of the inoculated –RC segments was pale green and stable, as was that of the non-inoculated controls. Correspondingly, tissue cells including epithelial cells of the cortical resin canal of the +RC segments were all dead, but those of the –RC segments and the controls were alive. When nematodes were inoculated onto the inner surface (cambium side) of a bark peeling at which cambial xylem cells were exposed, they did not kill the cambial cells. When inoculated on the transverse cut end of a bark peeling from which nematodes would enter resin canals, nematodes killed all cells in the peeling. The above results indicate that nematodes do not kill cortical cells immediately after inoculation but become harmful to pine cells after living in cortical resin canals. Key words: Bursaphelenchus xylophilus, pine wilt disease, pine wood nematode, Pinus thunbergii, resin canal.
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Ishida, Kyoko, Taizo Hogetsu, Kenji Fukuda, and Kazuo Suzuki. "Cortical responses in Japanese black pine to attack by the pine wood nematode." Canadian Journal of Botany 71, no. 11 (1993): 1399–405. http://dx.doi.org/10.1139/b93-168.
Full textAbstract:
Anatomical and cytochemical changes in the current-year stem cuttings of Japanese black pine (Pinus thunbergii) were investigated in the early stage of infection by a virulent isolate and an avirulent isolate of pine-wood nematode (Bursaphelenchus xylophilus), and an avirulent isolate of another nematode species, Bursaphelenchus mucronatus. Accumulation of lignin- and suberin-like substances around the resin canals in the cortex was shown as a new symptom of the infection by these isolates. Experiments with girdled cuttings demonstrated that more nematodes inhabit and move in the bark than in the xylem and pith at the early stage of infection by the virulent isolate. Death of pine cells occurred first in the epithelial cells of resin canals in the cortex after inoculation with the virulent isolate and then in the cortex and periderm, pith and xylem, and finally the cambium. In branches of 5-year-old seedlings inoculated with avirulent and B. mucronatus isolates, wound periderm was formed surrounding resin canals in the cortex, and cortical cells surrounding the wound periderm were alive. Evidence indicates that nematodes first enter resin canals in the cortex and then invade the surrounding cortical tissue, and that the ability of the virulent nematodes to move into the cortical tissue may be greater than that of the other isolates, accounting for differences in virulence. Key words: Bursaphelenchus xylophilus, Bursaphelenchus mucronatus, virulence, periderm, pine wilt disease, pine-wood nematode.
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EL KHOURY, YARA, GIUSEPPE BARI, NIKOLA GRUJIĆ, et al. "CAN THE RETURN TO THE NATURAL CONDITIONS OF IN VIVO PARASITIZATION INCREASE THE INFECTIVITY PERFORMANCE OF EPNS?" Redia 107 (July 31, 2024): 93–95. http://dx.doi.org/10.19263/redia-107.24.13.
Full textAbstract:
Experiments are in progress in Apulian asparagus fields for the control of Parahypopta caestrum (Hübner) (Lepidoptera, Cossidae) with microbial control agents (MCAs), mainly entomopathogenic nematodes and fungi.Different bioassays were carried out in laboratory and field conditions to prove the efficacy of native and commercial strains of the EPNs Steinernema feltiae (Filipijev), S. carpocapsae (Rhabditida, Steinernematidae) and Heterorhanditis bacteriophora Poinar (Rhabditida, Heterorhabditidae), and EPF Beauveria bassiana (Bals.-Criv.) Vuill. (Hypocreales, Cordycipitaceae). Among the field experiments, one was planned with the release of Galleria mellonella (L.) (Lepidoptera, Pyralidae) cadavers previously infected with native strains of EPN Steinernema feltiae and the comparison was carried out with a commercial strain of the same nematode species. Key Words: Parahypopta caestrum, Beauveria, Heterorhanditis, Steinernem
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Țoțoiu, Aurelia, Victor Niță, Valeria Abaza, George –. Emanuel Harcotă, Elena Bișinicu, and Victor Cristea. "Degree of Nematodes Worm Infection in Pelagic Fish Populations from the Romanian Black Sea waters." Cercetări Marine - Recherches Marines 51, no. 1 (2021): 140–55. http://dx.doi.org/10.55268/cm.2021.51.140.
Full textAbstract:
"Pelagic fish species can be affected by a series of infectious and parasitic diseases. The data used for this study are represented by the biological material collected between 2018 and 2019, from trap nets along the Romanian Black Sea waters. To establish the degree of parasitism, the following species of pelagic fish were studied: Sprattus spratus -sprat, Engraulis encrasicholus - anchovy and Trachurus mediterraneus- horse mackerel. Four species of endoparasites were identified, belonging to nematodes, as follows: Hysterothylacium aduncum, Contracaecum sp., Porrocaecumsp. and Anisakis sp. The parasites, especially found as larvae, more in free state and less trapped in the internal organs, infested the abdominal cavity, leading to degenerations, atrophies and reduction of the fish functions. The intensity of the parasitism infestation could be lethal, the size of the stocks being severely damaged. At the analysed fish species, the infestation degree was under 20 parasites per host, a low number of species recording the maximum value of 40 parasites per host. The parasites tend to accumulate with the increase of the fish's size, young stages being less affected. Key-Words: parasites, fish, nematodes, intensity, infestation degree "
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FAZIO, CRISTOFORO, DIEGO LEONE, and MIRELLA CLAUSI. "NEMATOLOGICAL POPULATION OF THE MUD VOLCANOES SALINELLE DEI CAPPUCCINI (PATERNÒ, CATANIA, ITALIA)." Redia 107 (September 13, 2024): 143–49. http://dx.doi.org/10.19263/redia-107.24.19.
Full textAbstract:
The municipality of Paternò (CT), located south-west of the slopes of Etna, hosts in its territory numerous sites in which natural manifestations occur characterized by emissions of high salinity fluids to the surface, linked to processes of secondary volcanism, called locally “Salinelle”. These are clayey areas, rich in chlorine, alkali and numerous metals, which, near the areas with greater emissive activity, do not allow the development of vegetation. The peculiarity of these areas and the lack of vegetation determine an environment in which the fauna, especially invertebrates, is extremely limited, if not absent, and is mainly made up of flying insects. Precisely to verify the possibility of survival and repopulation of the fauna in these environments, a study was carried out on the nematological communities in the Salinelle di Paternò area, and in particular in the area identified as “Salinelle dei Cappuccini di Paternò”. The sampling sites were identified both in active emission areas and in inactive areas with or without vegetation. The extracted nematodes were determined at the genus level and were used for ecological analysis. The results obtained demonstrate the progressive increase in biodiversity of the nematological community from the areas of active emission to those recolonized by vegetation. Key Words: mud volcanoes; nematodes community, nematological indices, biodiversity.
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Saichenko, I., and A. Antipov. "An epizootic situation is in relation to the nematodosiss of gastroenteric channel of dogs." Naukovij vìsnik veterinarnoï medicini, no. 1(154) (May 21, 2020): 54–62. http://dx.doi.org/10.33245/2310-4902-2020-154-1-54-62.
Full textAbstract:
Gastrointestinal nematodes are prevalent among dogs in Ukraine and most other countries. Economic losses in dog breeding for invasive diseases are diffi cult to calculate in material terms, but they are clearly manifested in terms of animal health. Therefore, the purpose of the research was to fi nd out the epizootic situation regarding the nematodes of the gastrointestinal tract in dogs of diff erent age, sex and breed groups in the Belotserkovsky district of Kyiv region. The studies were conducted on the territory of single-sector private sector farms of 15 settlements of Belotserkovsky district and on the territories of shelters for homeless animals of Belaya Tserkov. Koprovoskopichesky researches were carried out by the combined method standardized by Kotelnikov - Hrenov. According to the results of coprovoscopy of samples from dogs of the Belotserkovsky area, a signifi cant spread of nematodes of the gastrointestinal canal was established (EI was 50.18%). Eggs of such nematodes as Trichuris vulpis, Toxocara canis, Ancylostoma caninum, Toxascaris leonina, Strongyloides stercoralis were isolated. Diseases were recorded in the form of mono-invasions, among which the largest proportion of the aff ected were trihuriza (27.11%), toxocariasis (6.59), ankylostomosis (1.83%), and myxinvasions, which again led the trichuris. Animals from birth to 7 years were most aff ected. In terms of gender, females were more vulnerable. The highest incidence of invasion was among outbred dogs (51.56%). Most dogs in this group are aff ected by trichuris (54.55%) and myxinvasia (29.29%), which also included T. vulpis. Breeds German Shepherd, Dachshund, Russian Spaniel had the highest percentage of nematode infestations among all studied breeds. The leader among pathogens was T. vulpis, which covered more than half (52.63%) of rocks, myxinvasions were 28.94%, which included T. vulpis. The breeds of the Belgian shepherd, shih-tzu, Russian-European chamomile, alabai were resistant. Key words: dog, invasion, trichrosis, toxocariasis, ankylostomosis, toxascarose, distribution, koproovoskopichni research, extensiveness of invasion, intensity of invasion.
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Barros, Bruno Eduardo Alves, Elvira Maria Regis Pedrosa, Ênio Farias de França Silva, Mario Monteiro Rolim, and Patrícia Ângelo de Barros. "Mobility of Pratylenchus coffeae in segmented soil columns submitted to water flows and plant stimuli." Semina: Ciências Agrárias 40, no. 5Supl1 (2019): 2189. http://dx.doi.org/10.5433/1679-0359.2019v40n5supl1p2189.
Full textAbstract:
The root-lesion nematode Pratylenchus spp. causes a high-severity disease, promoting high economic losses in various crops of agricultural importance. The nematode control is difficult, especially after introduction into the area. Studies on the migration of this parasite in the soil are scarce. However, understanding nematode behavior in the soil is fundamental to increase the efficiency of management practices, especially in irrigated agriculture. This study aimed to evaluate the influence of water flow and plant stimulus on Pratylenchus coffeae mobility in segmented soil columns. The columns were segmented into 11 rings of 1 cm long filled with washed sand, one of the ends exposed to a bait, and submitted to flows of 0, 3, 7 cm3/min of water. Baits for nematode attraction and repelling consisted of sectioned tubers of yam (Dioscorea cayennensis) and cut leaves of neem (Azadirachta indica), respectively, and the absence of baits as the control. Nematodes were injected into the central segment of the column, and migration and presence in water leaching were determined five days after soil infestation. Mobility of P. coffeae varied with water flow and bait type. In the absence of water flow, nematodes migrated in the opposite direction to the neem baits, but migration was well distributed in the presence of yam baits, with specimens present in all column segments. The nematode had significantly higher resistance to water flow of 3 cm3/min in the presence of yam baits. No nematodes were found in the water leached at flows of 3 and 7 cm3/min in the absence of bait. Key words: Azadirachta indica. Dioscorea cayennensis. Lesion nematode. Soil dispersion.
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Amankwa, G. A., A. D. White, T. W. McDowell, and D. L. Van Hooren. "Pearl millet as a rotation crop with flue-cured tobacco for control of root-lesion nematodes in Ontario." Canadian Journal of Plant Science 86, no. 4 (2006): 1265–71. http://dx.doi.org/10.4141/p05-163.
Full textAbstract:
In Ontario, flue-cured tobacco (Nicotiana tabacum L.) growers routinely fumigate their soils to control root-lesion nematodes (Pratylenchus penetrans Cobb). Studies suggest that planting pearl millet (Pennisetum glaucum L.) as a rotation crop may control the nematodes; winter rye (Secale cereale L.), the crop commonly grown in rotation with tobacco, is susceptible to the nematodes. In 2002, plots of forage millet (var. CFPM 101), grain millet (var. CGPMH-1) and winter rye were established at three sites and in 2003, tobacco was grown at these sites in non-fumigated plots where the rotation crops grew, except for a winter rye/fumigation treatment. The goal was to evaluate P. penetrans populations and tobacco yield and quality in the millet rotations relative to the traditional rye-fumigation system. In 2002, initial P. penetrans populations assessed in the spring were similar for all treatments; however, the final populations and consequently the ratios of final populations/initial populations (Pf/Pi) consistently differed among treatments. The Pf/Pi ratios ranged from 0.07 to 0.79 for forage millet, from 0.18 to 0.94 for grain millet and from 2.33 to 21.65 for rye. In 2003, P. penetrans populations in tobacco plots previously cropped to either type of millet were comparable with those detected in fumigated winter rye plots. Compared with tobacco following rye without fumigation, tobacco yield was 14 to 51% higher following rye with fumigation, 19 to 70% higher following forage millet and 18 to 65% higher following grain millet. Grade index was unaffected. Results indicate that pearl millet offers an alternative to fumigants for the suppression of P. penetrans population and provides equivalent gross returns. Key words: Pennisetum glaucum, rotation crop, Nicotiana tabacum
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VOVLAS, ALESSIO, ELENA FANELLI, ALBERTO TROCCOLI, and FRANCESCA DE LUCA. "SOMATOMETRIC CHARACTERS OF AN ANATONCHUS POPULATION (NEMATODA MONONCHIDAE) FROM GREECE: OBSERVATIONS ON ITS PREDATORY ABILITY." Redia 107 (September 13, 2024): 131–34. http://dx.doi.org/10.19263/redia-107.24.17.
Full textAbstract:
A population containing specimens belonging to Anatonchus genus collected along the edge of irrigation canals from Filippiada, Epirus (N.W Greece) is described and illustrated. The predatory ability and type of feeding against phytoparasitic free-living nematodes and larval specimens of insects (Curculionoidea: Coleoptera) are also showed. All observations were based on direct analysis of the gut contents in glycerine infiltrated specimens. The feeding type of its trophic activity was characterized by engulfing whole and intact prey, while in cases of large size nematode prey or larvae of insects, the piercing and content-sucking feeding type was observed. Several entire tylenchid and/or dorylaimid nematode species were observed in the digestive tract of Anantonchus sp. (75%). No evidence of preference for selecting its prey species was observed. Key Words: Greece, Mononchida, Predation, Potential Biological Control, Taxonomy
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Thiéry, M., and D. Mugniéry. "Microsatellite loci in the phytoparasitic nematode Globodera." Genome 43, no. 1 (2000): 160–65. http://dx.doi.org/10.1139/g99-106.
Full textAbstract:
A Globodera pallida genomic library, population Guiclan (Pa2/3), was screened for TG and TC microsatellite motifs. Screening of 50 000 clones revealed 48 positive matches. After sequencing, primers were designed to amplify 14 microsatellite loci. The specificity of the loci was tested with DNA templates of other populations of G. pallida, and also on other species of Globodera. Appearance of amplification products on several of these DNA templates showed that the microsatellite flanking regions are relatively conserved between G. pallida populations as well as between Globodera species. Evidence for allele polymorphism between individuals was demonstrated by using nine loci primers, in G. pallida population Guiclan and from a population of a closely related species G. "mexicana". Some alleles appeared to be species specific. Key words: Globodera, microsatellites, nematodes, phytoparasite, allele frequency.
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ZAREI, SHEYDA, and SEDIGHE AZIMI. "FIRST MOLECULAR CHARACTERIZATION OF DITYLENCHUS FILIMUS ANDERSON, 1983 (NEMATODA ANGUINIDAE) BASED ON THE POPULATION FROM IRAN." Redia 106 (October 23, 2023): 97–105. http://dx.doi.org/10.19263/redia-106.23.11.
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During a survey on the biodiversity of plant-parasitic nematodes in Khuzestan province (southwest Iran), Ditylenchus filimus was discovered in the rhizosphere of date palm. The morphological and morphometric data were provided for the recovered species. The morphological characters of Iranian population are in agreement with the type population and other populations of this species. Molecular phylogenetic analyses of the species with representatives of the family Anguinidae were discussed using partial sequences of the small subunit, D2-D3 expansion segments of the large subunit, and internal transcribed spacer regions of ribosomal DNA (SSU, LSU D2-D3 and ITS rDNA) based on Bayesian inference (BI). To the best of our knowledge, this is the first report of molecular characterization of this species. Key Words: 18S rDNA, D2-D3 LSU rDNA, ITS rDNA, Ditylenchus, morphometric data, phylogeny
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Kerr, Sylvia Joann. "Frequency of recovery of myxomycetes from soils of the northern United States." Canadian Journal of Botany 72, no. 6 (1994): 771–78. http://dx.doi.org/10.1139/b94-097.
Full textAbstract:
Soil samples from the northern United States in regions subject to acid deposition and from other regions where acid deposition is not a problem were cultured so that estimates of myxomycete frequency could be made. The presence of myxomycetes, protostelids, cellular slime molds, myxobacteria, and nematodes was recorded as were physical and chemical characteristics of the soils. No significant correlations were noted between the numbers of the soil microorganisms in the enumerated classes. Myxomycetes and protostelids were recovered from only 26 of the 81 soil samples. Their presence was correlated with levels of Ca2+, K+, and organic matter, and they were recovered from acidic soils and from soils in regions subject to acid deposition. Characteristics of soils that yielded cellular slime molds and myxobacteria were also analyzed. Key words: myxomycete, dictyostelid, myxobacteria, pH, acid deposition, soil organisms.
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Verheles, Pavlo, Nataliia Pinchuk, and Tetiana Kovalenko. "THE STUDYING OF DYNAMICS OF THE DISTRIBUTION OF GOLDEN POTATO NEMATODES IN UKRAINE AND SEPARATE FACTORS ITS REGULATION." Agriculture and Forestry, no. 1 (April 28, 2020): 149–61. http://dx.doi.org/10.37128/2707-5826-2020-1-11.
Full textAbstract:
In recent years, the main sowing areas of potatoes have moved from collective farms to the private sector, which makes it difficult to detect nematodes and establish their level of harmfulness in different regions of Ukraine. The cultivation of potatoes in monoculture for many years, the unpredictability of the existing seed system of regular maintenance of individual farms with healthy planting material, the lack of knowledge about the protection of plants against nematodes, contribute to the spread of globoderosis in new territories. Research strategy to protect the potato crop from nematodes should be aimed at a low-energy and environmentally friendly system based on the use of nematodes, the correct application of crop rotation crops, the introduction of organic and mineral fertilizers, the quality of planting material, since chemical hazards protect the environment. The outstanding issues in terms of regulating the abundance of golden potato nematodes remain the factors of the agrochemical properties of soils and their relationship with the pest size, aspects of the use of different potato precursors in terms of influencing the prevalence of the nematode, and estimating the monitoring status of its comparative numbers. The article summarizes the results of quarantine monitoring of the distribution of the golden potato nematode (Globodera rostochiensis Woll) in Ukraine and by region. A comparison of the pest prevalence rate over ten years of quarantine monitoring has been conducted and conclusions have been made regarding their success at the regional level. The phenological development of the pest is specified taking into account the climatological features of the Vinnitsa region. A review of the features of biology and the pest development cycle is made on the basis of which briefly described signs of potato damage in the field. On the basis of field studies, the effectiveness of the control of the potato nematode was evaluated by introducing crop rotation and selecting the appropriate alternation of different plants. The effectiveness of the use of potato varieties resistant to the nematode was assessed, and the level of their productivity against an infectious background was determined in comparison with the variety unstable to the pest. Conclusions have been made in the main areas of restricting the spread of the potato nematode in the private sector of potato cultivation in permanent crops. Key words: golden potato nematode, yield, varieties, crop rotation, prevalence.
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Zubova, Nataliia, Serhii Naumenko, and Viktor Somov. "TYPES OF WATERMARKS ON BANKNOTES AND METHODS OF THEIR IMITATION." Criminalistics and Forensics, no. 67 (August 9, 2022): 448–65. http://dx.doi.org/10.33994/kndise.2022.67.45.
Full textAbstract:
The article deals with the consideration of ways to imitate watermarks in the manufacture of counterfeit banknotes. The watermark is an important public security element for banknotes issued for cash circulation. The basis of any banknote related to paper money is banknote paper. The article briefly describes the stages of the technological process of manufacturing banknote paper and methods for forming watermarks on it. The criteria for the classification of watermarks depending on their location on the banknote (general, local stripe), in relation to the overall tone of the paper (one-tone, two-tone, local, filigree, combined), composition, as well as drawings illustrating these types of watermarks are given. signs. The watermarks developed using modern technologies in recent decades are described, as well as their illustrations. The levels of counterfeiting are determined depending on the subject and its technical capabilities for the manufacture of counterfeit banknotes. The ways of imitation of watermarks are generalized. Firstly, watermarked paper intended for other purposes can be used to make counterfeit banknotes. Secondly, the imitation of watermarks is possible using specially made forms: embossed, used for embossing paper, and printed-screen or letterpress. Widely used to imitate watermarks of copiers. Less common are watermarks, which are imitated using fat-containing substances, or painted with a dye. The article provides examples of the implementation of the relevant methods with their illustration based on studies of counterfeit banknotes. Key words: banknote, banknote paper, watermark, types of watermarks, watermark imitation.
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Onkendi, Edward, and Lucy Moleleki. "Development of a real-time PCR assay to detect and quantify the tropical root-knot nematode (Meloidogyne arenaria) in latently infected potato seed." African Phytosanitary Journal 3, no. 1 (2022): 1–14. http://dx.doi.org/10.52855/ikem3740.
Full textAbstract:
Tropical root-knot nematodes (M. incognita, M. arenaria and M. javanica) are a serious problem to most crops, both cultivated and non-cultivated. In the recent past, accurate detection and discrimination of tropical Meloidogyne spp. has been achieved through the development of DNA-based diagnostic assays among others real-time polymerase chain reaction (qPCR) to complement results obtained using morphological and biochemical-based diagnostic methods. However, despite the developments, most of the current methods have not been optimized to quantify and characterize the tropical Meloidogyne spp. particularly in latent infections. Currently, this is a big problem in potato seed production where latently infected tubers often get distributed resulting in the distribution of root-knot nematodes to new areas. In this study, we sought to develop and validate a diagnostic method of quantifying root-knot nematode, M. arenaria in latently infected potato seed tubers. Study findings indicated that there is a high (R2 > 0.953) and significant (P < 0.05) positive correlation between target DNA concentration and Ct values, and the assays can be used to quantify as low as 1.53/100th of DNA associated with individual juvenile nematodes. Using high resolution melting curve analysis, Meloidogyne arenaria samples produced specific melting peaks (79.32 ± 0.029°C, P < 0.05) clearly distinguishing themselves from other tropical Meloidogyne species (M. incognita 79.50 ± 0.022°C and M. javanica 79.96 ± 0.046°C). The development of the high-resolution melting curve (HRMC) analysis method for quantification and characterization of M. arenaria in this study will greatly improve on accurate screening of this pathogen during latent infections to curb potato losses often associated with distribution of infected seed. Key words: Root-knot nematode, real-time PCR, high resolution melting curve analysis, South Africa, Meloidogyne spp. and potato seed
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Nyandiala, A., T. Amakhobe, and S. Okoth. "Occurrence, abundance and distribution of soil nematodes associated with groundnut farming in Kenya." African Journal of Food, Agriculture, Nutrition and Development 23, no. 8 (2023): 24293–316. http://dx.doi.org/10.18697/ajfand.123.23270.
Full textAbstract:
Groundnut is a major cash crop grown in tropical and subtropical regions. In Kenya, groundnut is mostly grown in the Western and Nyanza regions and has been ranked the fourth cash crop of the Lake Victoria Basin (LVB). However, groundnut production in Kenya has continued to decline with farmers attaining less than 50 % of the yield potential of 700 to 1400 kg/ha. Yearly statistical reports by Agriculture and Food Authority (AFA), Nuts and Oil Crops Directorate for the last seven years, show the decline has been consistent. In 2019/2020 AFA reported there was a decrease of 216 Mt in Homa Bay and 30 Mt in Kisumu. Yield loss is attributed to lack of quality improved seed and pests’ infestation during growth and storage. Plant parasitic nematodes (PPN) are the major pests of groundnut worldwide. This study sought to investigate the occurrence of nematode communities (PPN and non-parasitic nematodes (NPN) in soils cultivated with groundnuts in the LVB and to determine the effect of farmyard manure application on their presence. Six peanut varieties (4 improved and 2 local) were cultivated in Nyakach and Karachuonyo in March to August in 2021 and 2022. Soil samples, groundnut roots and pods were collected. A modified Baermann’s, maceration methods and filtration technique was used to isolate nematodes from the soil, groundnut pods and roots. Multi-stage Analysis of variance (ANOVA) was used to determine any significant differences in abundance and richness while the Shannon index compared diversity of PPN and NPN among the farms in two seasons and regions. Eleven genera of PPN: Aphelenchoides, Meloidogyne, Pratylenchus, Helicotylenchus, Tylenchus, Scutellonema, Trichodorus, Hemicycliophora, Tylenchorhynchus, Rotylenchulus and Criconema. spp., and three genera of NPN; Rhabdittes, Dorylaimus spp. and Predators were categorized. Aphelenchoides and Meloidogyne were the most abundant PPN and Rhabdites NPN in both regions and seasons. Application of farm yard manure led to decline of abundance of PPN and an increase in NPN. The results confirm the presence of PPN in the LVB groundnut growing regions and the potential use of farm yard manure in their management. This study recommends further investigation on actual damage potential of these PPN and their management strategies. Key words: Arachis hypogaea, Soil nematodes, Meloidogyne, Aphelenchoides, Rhabdites, Pratylenchus, Helicotylenchus
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South, David B., William A. Carey, and Scott A. Enebak. "Chloropicrin as a soil fumigant in forest nurseries." Forestry Chronicle 73, no. 4 (1997): 489–94. http://dx.doi.org/10.5558/tfc73489-4.
Full textAbstract:
Chloropicrin has been tested as a soil fumigant in forest nurseries throughout the world. From 1944 to the late 1960's, tests were conducted in Australia, Canada, Netherlands, New Zealand, the United Kingdom and the United States. Since 1985, studies have been conducted in Georgia, Mississippi, South Carolina, Texas, Virginia, Washington and Wisconsin. In Wisconsin, chloropicrin reduced soilborne pathogens as effectively as twice as much methyl bromide. Advantages of chloropicrin as a soil fumigant in southern pine nurseries include: efficacy similar to methyl bromide (in regards to reduction in fungi, nematodes and insects), an increase in Trichoderma populations, it is not a Class 1 ozone depleting substance, and no plastic tarp is required. Adding chloropicrin to other fumigants has increased the spectrum of biological activity. A disadvantage of chloropicrin is that it has less herbicidal activity than methyl bromide. Key words: fungicide, methyl bromide, disease, nursery management, seedbeds
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de Rooij – van der Goes, P. C. E. M., W. H. van der Putten, and B. A. M. Peters. "Effects of sand deposition on the interaction between Ammophila arenaria, plant-parasitic nematodes, and pathogenic fungi." Canadian Journal of Botany 73, no. 8 (1995): 1141–50. http://dx.doi.org/10.1139/b95-124.
Full textAbstract:
Ammophila arenaria is a dominant sand-fixing plant species of the European coastal foredunes. It remains vigorous under regular burial conditions on seaward slopes, but starts to degenerate when sand accumulation diminishes. Several hypotheses have been put forward to explain this degeneration. In this study, we test the hypothesis that upward growth of plants following sand burial enables them to escape harmful soil organisms. Plants in a degenerating field stand of A. arenaria and potted plants grown in sterilized sand (outdoor pot experiment) were buried with sterilized or nonsterilized sand. Burial in both sterilized and nonsterilized sand resulted in stem elongation, increased numbers of living shoots, and increased shoot and root biomass. However, when plants were grown in and buried with sterilized sand, the numbers of shoots were significanlty higher than those buried with nonsterilized sand. The new root zone of buried plants was colonized by pathogenic soil organisms (nematodes and fungi) during the same growing season. It is concluded that by upward growth through pathogen-free sand, the plants benefit, at least temporarily, from escaping its pathogens and parasites. Key words: clonal growth, upward growth, migration, soil-borne disease, growth reduction.
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Cogger, C. G., T. A. Forge, and G. H. Neilsen. "Biosolids recycling: Nitrogen management and soil ecology." Canadian Journal of Soil Science 86, no. 4 (2006): 613–20. http://dx.doi.org/10.4141/s05-117.
Full textAbstract:
Biosolids are municipal wastewater treatment solids that meet regulatory standards for land application. Most biosolids are a rich source of N, P, and micronutrients. Although the use of biosolids on food crops remains controversial in the public eye, decades of research have led to the development of regulations for the safe and beneficial use of biosolids in agriculture. Emerging areas of research include biosolids in commercial and home horticulture, the fate of pathogens and organics in biosolids, the use of biosolids in the remediation of contaminated sites, and biosolids effects on soil ecology. Nutrient management remains the most critical day-to-day issue for land application of biosolids. Recent research on plant-available nitrogen (PAN) in biosolids has found that N availability is similar over a range of biosolids processing types, and that growing-season climate is a key factor affecting available N. Regionally based predictions of PAN have been developed for the United States, and could be extended into Canada. Relatively little is known about the effects of biosolids applications on soil ecology, but soil nematodes offer an opportunity to evaluate the structure and function of the soil ecosystem following biosolids applications. We have studied responses of nematode communities to application of municipal biosolids and composts, in forage production systems and orchards. Both types of amendments increased the abundance of enrichment opportunists, for up to 3 yr after single applications. These data on the persistence of increased enrichment opportunists have provided insight into the longevity of amendment-induced enhancement of biological activity and nutrient cycling. Cumulative biosolids applications of 90 Mg ha-1 have caused reductions in abundance of pollutant-sensitive Dorylaimida. The extent to which this change is the result of metal or nutrient loading is unclear and deserves more detailed study. Key words: Biosolids, plant-available nitrogen, soil ecology, nematodes
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Costea, M., S. E. Weaver, and F. J. Tardif. "The biology of Canadian weeds. 130. Amaranthus retroflexus L., A. powellii S. Watson and A. hybridus L." Canadian Journal of Plant Science 84, no. 2 (2004): 631–68. http://dx.doi.org/10.4141/p02-183.
Full textAbstract:
A review of the biological information published after 1980 is provided for three species of the genus Amaranthus: A. retroflexus L., A. powellii S. Watson and A. hybridus L. The three species are noxious weeds introduced to Canada from southern North America. Their geographical distribution has remained almost unchanged since the original paper published in 1980. The plants exhibit a high phenotypic plasticity and genetic variability and they easily adapt to a multitude of agrestal and ruderal habitats. The seeds contribute to a persistent seed bank; they exhibit a variable dormancy and polymorph germination as a result of maternal, genetic and environmental factors. Growth is rapid and plants produce a large number of viable seeds. The three species have developed multiple resistance to triazine and acetolactate-synthase-inhibiting herbicides. They are alternate hosts to many insects, nematodes, viruses, bacteria and fungi that affect cultivated plants. Key words: Amaranthus retroflexus, Amaranthus powellii, Amaranthus hybridus, weed biology, ecology, taxonomy, herbicide resistance
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Costea, Mihai, and François J. Tardif. "The biology of Canadian weeds. 131. Polygonum aviculare L." Canadian Journal of Plant Science 85, no. 2 (2005): 481–506. http://dx.doi.org/10.4141/p03-187.
Full textAbstract:
A review and assessment of biological information as well as personal data are provided for Polygonum aviculare in Canada. The species has been revised taxonomically and the six subspecies that occur in Canada are presented. Three of the subspecies, P. aviculare subsp. aviculare, P. aviculare subsp. neglectum and P. aviculare subsp. depressum are weeds introduced to Canada from Europe. A fourth subspecies, P. aviculare subsp. buxiforme is apparently native to North America. The geographical distribution of the latter four subspecies is very wide. Plants exhibit a high phenotypic plasticity and genetic variability, and they easily adapt to a multitude of agrestal and ruderal habitats. The seeds have a variable dormancy and polymorphic germination as a result of heterocarpy, genetic and environmental factors. In other areas (Europe), the species has developed resistance to triazines. Plants are hosts to nematodes, viruses, and fungi that also affect cultivated plants. Key words: POLAV, ecology, distribution, taxonomy
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Khuramshina, D. Z., O. I. Orenburkina, R. R. Bakiev, and A. E. Babushkin. "Ocular dirofilariasis mimicking orbital tumors: A case report." POINT OF VIEW. EAST – WEST, no. 4 (December 28, 2023): 59–64. http://dx.doi.org/10.25276/2410-1257-2023-4-59-64.
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Dirofilariasis (from Latin «ominous thread») is transmissible facultative zoonotic biohelminothosis, caused by thread-like helminth from nematodes of the genus Dirofilaria. Two species are spread throughout Russia – D. repens and D. immitis. Dirofilariasis prevalence increase and expansion of the prevalence area cause ophthalmologists to raise concern over it. The article presents a clinical case report of a female patient, 71, with dirofilariasis masquerading as orbital tumors. The patient underwent transcutaneous orbitotomy and ‘tumor’ resection. The subsequent pathoanatomical examination of the resected conglomerate revealed the presence of helminth, whose fragments were later identified as D. repens in the laboratory of sanitary and epidemiological station. Abnormal clinical picture of dirofilariasis, and its ocular capsular form in particular, determines that the rare disease often mimics various non-parasitic disorders. This circumstance can hinder the diagnosis and delay proper treatment, so it is necessary to raise clinicians’ awareness and alertness about this ocular pathology. Key words:: dirofilariasis, orbital tumors, surgical treatment, Dirofilaria repens
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AYDINLI, GÖKHAN, and SEVİLHAN MENNAN. "BIOFUMIGATION WITH WINTER BRASSICA SPECIES SUPPRESSES THE ROOT-KNOT NEMATODE AND INCREASES THE TOMATO YIELD." Redia 108 (March 28, 2025): 97–105. https://doi.org/10.19263/redia-108.25.11.
Full textAbstract:
Root-knot nematodes (RKN) are responsible for significant crop losses in vegetables worldwide and are ex- tremely difficult to control. Biofumigation is one of the most important alternatives that can be used to manage RKN. This study aimed to investigate the effects of biofumigation of winter brassica species on RKN and the yield of tomatoes. Six different brassicas and nematode-susceptible spinach plants as control from winter crops were used in trials in 2 greenhouses heavily infested with Meloidogyne arenaria. After Brassica species were grown until the flowering period, they were mixed into the soil and covered with polyethylene plastic film. At the end of one month, the gall index, female, and total nematode populations in the roots were determined, and nematode-susceptible tomato seedlings were planted in all plots. Each plot’s RKN population in the soil was counted monthly. At the tomato harvest, the growth parameters of the plants were determined, the tomato roots were evaluated using a 0-5 gal index, and the tomato yield was recorded. The soil’s RKN population was lower in arugula, redhead (RHR), and whitehead radish (WHR) cultivated plots than in the others. The gall indexes of tomatoes after growing RHR and WHR were 2.25 and 2.50 for arugula but 4.80 for spinach. Tomato yield in the plots where RHR, turnip, and WHR were grown previously increased by 249%, 200%, and 174%, respectively. Brassica species positively impact tomato plant growth and yield and can suggest biofumigation with arugula, RHR, and WHR for root-knot nematode-infected areas. Key Words: Root-knot nematodes; Brassica spp.; biofumigation; tomato yield.
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JUMA, N. G., and C. C. MISHRA. "EFFECT OF AN ANNUAL AND A PERENNIAL CROP ON TROPHIC GROUP DYNAMICS OF NEMATODES." Canadian Journal of Soil Science 68, no. 1 (1988): 101–9. http://dx.doi.org/10.4141/cjss88-009.
Full textAbstract:
Adult and juvenile nematode distribution and trophic group dynamics were studied in oat (Avena sativa L.) and alfalfa (Medicago sativa L.) plots of a 5-yr rotation at Breton, Alberta. Nematodes were separated into two groups: (i) adults including the late juveniles and (ii) juveniles. The adults and the late juveniles were further separated into four trophic groups: (i) plant parasites, (ii) microbivores, (iii) miscellaneous feeders and (iv) predators. Adults accounted for 83% of the total population in the oat plot and 79% in the alfalfa plot. There were no significant differences in percent distribution of adults between plots over the season or at a given date. The average density of adults over the season in the oat plot (3.3 × 106 individuals m−2) was greater than that in alfalfa plot (2.1 × 106 individuals m−2, P < 0.001). Adult density in the oat plot increased steadily from 3.2 × 106 to 4.2 × 106 individuals m−2 between July and September. There was a sharp decline after harvest. In contrast, the adult population in the alfalfa plot remained steady over the growing season. Juvenile density showed similar trends as the adults. Distribution of microbivores, plant parasites, miscellaneous feeders, and predators, was 63, 22, 13, and 2% in oat and 51, 34, 13, and 2% in alfalfa plot, respectively. Crop effect on microbivores and plant parasites was significant at P < 0.05. Our study showed that microbivores are the dominant group in cultivated soils and plant parasites build up in the presence of living roots. Key words: Microbivores, miscellaneous feeders, nematodes, plants parasites, predators, trophic groups