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Background: The privileged geographical position of Morocco as a Mediterranean country confers upon it a pivotal role in both regional and global food security. Leveraging its diverse geography and varying climate, the country contributes significantly to the worldwide supply chain by cultivating a wide array of crops. However, the extensive use of chemicals in the production process, particularly for pest management, has led to substantial degradation of environmental resources. Plant parasitic nematodes (PPNs) pose a significant threat to agricultural productivity, causing considerable crop yield losses. With growing concerns about the environmental and human health impacts of nematicides, restrictions on their usage have prompted the exploration of alternative control strategies for effective safe PPNs management. Main body: The present review provides a comprehensive overview of research on plant parasitic nematodes (PPNs) in Morocco. It covers PPN taxa inventory, diversity, prevalence on different crops, and responses to environmental factors. The review also maps the distribution of the most dangerous genera, analyzes biological control methods for root knot nematodes Meloidogyne particularly, and identifies gaps and future research needs for sustainable PPN management. A total of 61 genera of PPNs were identified in Morocco, with Meloidogyne spp. being the most prevalent and dangerous genus, posing a serious threat to crop production in the country. The extensive distribution of PPNs, notably root knot, may be attributed to factors such as contaminated plant material and a lack of farmer awareness. Biological agents from Morocco's ecosystems, including plant extracts, nematophagous fungi, and entomopathogenic nematodes, showed great potential as control agents for root knot nematodes. This review significantly contributes to Mediterranean and global nematological knowledge by providing insights into the diversity and sustainable management of plant parasitic nematodes. Conclusion: The biological richness of Moroccan ecosystems can provide valuable resources for researchers in developing commercial effective bionematicides for plant pests. [ABSTRACT FROM AUTHOR]

Root-knot nematodes (RKNs), Meloidogyne spp., are globally important plant-parasitic nematodes with a very broad host range including cucumber. In this research, we evaluated the nematicidal efficacy of commercial Abamectin-CAP (Vertimec 1.8% EC) versus Iranian-produced Abamectin-IAP (Vertimec 2% EC) compared with Cadusafos (Rugby), Trichodermaharzianum T-22 (Tricuran-P), and chicken manure against the cucumber RKN, Meloidogynejavanica, in commercial greenhouses. We also analyzed the effect of the products and amendment on several soil enzymes because of their significant roles in increasing the rate of decomposition and release of plant available nutrients. The results showed highly significant differences among treatments. The highest reduction of second-stage juveniles (J2) in the soil was recorded for Abamectin-CAP and Abamectin-IAP (93–95%), followed by Tricuran-P (90%), Rugby (82%) and chicken manure (65%). Similar results were obtained for the number of J2 and eggs in the root (94%), root gall indexes (94%), egg mass indexes (74–79%), and reproduction percentage (5.4–8.3%) in the Abamectin-CAP and Abamectin-IAP treatments. Enzyme activity assays showed that Rugby and chicken manure both caused a significant decrease in urease activity, followed by Abamectin-CAP and Abamectin-IAP. The highest alkaline phosphatase activity was observed for Abamectin-IAP and Abamectin-CAP, whereas the highest acidic phosphatase activity was in the Abamectin-CAP treatment. The results form a basis for developing integrated pest management strategies for RKN in cucumber. [ABSTRACT FROM AUTHOR]

Plant-parasitic nematodes are significant pests for many crops with considerable economic impact worldwide. Alternatives to highly toxic soil fumigants and nematicides are urgently sought after. Fluazaindolizine is a fluorinated nematicide with a novel, unknown mode-of-action and very low mammalian toxicity. The current research investigated the early responses of several plant-parasitic nematode species to the compound by in vitro mortality and parasitism trials with nematode-susceptible host plants. After a 72-h in vitro exposure time, fluazaindolizine exhibited the most potent toxic activity against the second-stage juveniles (J2) of Meloidogyne incognita and Tylenchulus semipenetrans with LC50 values of 177.14 and 355.2 mg L−1, respectively. Pratylenchus brachyurus, J2 of the Heterodera schachtii, and eggs of M. incognita were considerably less sensitive to the nematicide. The fitness of M. incognita J2 was strongly affected when exposed to various concentrations of fluazaindolizine for 12 h before inoculation of cucumber seedlings in soilless seed pouches. The lowest level of 5 mg L−1 reduced root galling, egg mass production, and the number of eggs to about 25% compared to the water control. In another bioassay, H. schachtii J2 were exposed to fluazaindolizine at 100 and 200 mg L−1 for 72 h before used to infest soil with 3-day-old radish seedlings. About 39.8% and 59.6%, respectively, fewer J2 invaded the roots compared to the control. In conclusion, the tested nematode species varied considerably in their in vitro mortality following fluazaindolizine exposure. However, the bioassays demonstrated that parasitism was already severely impacted at non-lethal concentrations and short-term exposure to the nematicide. [ABSTRACT FROM AUTHOR]

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]

Efficacy of 23 actinomycete strains isolated from different Egyptian extreme biotopes (sandy soils of different localities at South Saini) and their secondary metabolitesas as bio-control agents against the root-knot nematode, Meloidogyne incognita were evaluated. Culture filtrates of isolated soil actinomycetes exhibited variable response against egg hatchability and mortality of root-knot nematode. Among the tested actinomycete isolates only 5 isolates, encoded SET-6, SNQR-9, SDB-14, SACR-18 and SWW-19 showed the highest larivcidal and ovicidal activities (≥70%). According to such primary screening, each of SET-6, SNQR-9 and SWW-19 isolate filtrates were selected as the most potent ones. Thereafter, the efficacy of different concentrations of dried isolate filtrates (100, 50, 25 and 12.5 mg/ml) exhibited the highest larval mortality (100, 82.9 and 76.0%) and the highest inhibition of egg hatchability (96.6, 84.1 and 87.5%) for SET-6, SWW-19 and SNQR-9 isolates, respectively at the highest applied concentration (100%). Isolate SET-6 by its lowest LC50 values (17.02 and 18.01) as larvicide and ovicide, respectively) was selected as the most promising nematicidal isolate. [ABSTRACT FROM AUTHOR]

An experiment was conducted on 15-year-old mandarin (Citrus reticulata) cv. Baladi trees grafted on sour orange (C. aurantium) rootstock infected with the citrus nematode (Tylenchulus semipenetrans) to evaluate potential effect of seven treatments on its management. They were: entomopathogenic nematodes (EPN) in two formulations: Heterorhabditis bacteriophora-infective juveniles (IJs) within infected Galleria mellonella L. cadavers or IJs in water suspensions, as well as Bio-Nematon (Paecilomyces lilacinus), Stanes sting (Bacillus subtilis), Micronema (Serratia sp., Pseudomonas sp., Azotobacter sp., B. circulans and B. thuringiensis), Nema Plus Zero (a.i. 2.4-dihydroxybenzene 12.5%, 2.4-dichloropropene and Inert Ingredients 81.5%) and Carbofuran (furadan) in addition to the untreated check. All the tested materials suppressed T. semipenetrans populations and increased fruit yield. Micronema, which had the above-mentioned biocontrol agents, resulted to the highest fruit yield (229%) of control yield. Nematode levels were 20 and 26% of control levels, 27 weeks following treatment with Bio-Nematon and Stanes sting, respectively. The tested materials reduced all T. semipenetrans life stages but the magnitude of the reduction differed with time of sampling, life stage and the applied material. [ABSTRACT FROM AUTHOR]

In order to find a novel, leading nematicide compound, a series of pyridine-pyrazole amide derivatives containing 1,2,3-triazoles were synthesized via click chemistry in a one-pot reaction. Their structures were characterized by proton nuclear magnetic resonance ( H NMR), C NMR, F NMR and high-resolution mass spectrometry (HRMS). Preliminary bioassays showed that most of the synthesized compounds exhibited good inhibitory activity in vivo against Meloidogyne incognita at 25 mg L. Among the tested compounds, 3a, 3e, 3f, 3g, 3j, 3m, 3q, 3s, 3t, 3v and 3w exhibited 100 % inhibition rates. Moreover, 3k displayed a 92.4 % inhibitory activity at 10 mg L. This investigation suggested that this pyridine-pyrazole amide containing a 1,2,3-triazole scaffold could be further optimized to explore novel, high-bioactivity nematicidal leads. [ABSTRACT FROM AUTHOR]

Achieving food sufficiency in a sustainable manner is a major challenge for farmers, agro-industries, researchers and governments. Amongst agricultural pests supressing crops, root-knot nematodes ( Meloidogyne spp.) represent possibly the world's most damaging one, the control of which has been mainly based on chemical nematicides. In the recent years the environmental, food safety and animal welfare issues pose the need for alternative nematode control measures. Screening naturally occurring compounds in plants, involved in the complex chemical-mediated interactions between a plant and other organisms in its environment, can provide with innovative nematode control measures that can be safely used in integrated pest management programs. The Mediterranean Basin is an area where various soils and climatic conditions allow a vast plant biodiversity providing with chemical botanicals of significant nematicidal potency. This is a review on the Mediterranean botanicals that can control Meloidogyne spp. [ABSTRACT FROM AUTHOR]

The development of sustainable cropping systems is a key priority for agronomists and crop scientists. A first step involves understanding the relationship between cropping system performance and farmers' practices. To complete this step, a methodological framework entitled Regional Agronomic Diagnosis (RAD) has been developed. During the last ten years, the scope of the regional agronomic diagnosis has been enlarged to include several factors describing crop quality and the environmental impact of cropping systems. Regional agronomic diagnosis has led to several major advances such as (1) the assessment of the effect of preceding crop and soil structure on malting barley quality in France and (2) the assessment of the effects of ploughing, nematicide use and fertilisers on soil properties in intensive banana plantations in the West Indies. Improvements have also been gained in methodology, particularly by the selection of indicators for assessing the effects of crop management, soil and weather conditions, and data analysis. Finally, regional agronomic diagnosis has been integrated into more general approaches of agricultural development. We review here this methodological progress. [ABSTRACT FROM AUTHOR]

Glasshouse and field experiments were conducted to determine the effects of biocides and rotation breaks on deleterious soil organisms associated with the poor early growth and subsequent yield decline of sugarcane grown in continuous monoculture. Fumigation of a soil that had been under sugarcane monoculture with minimal breaks for more than 30 years markedly improved the health and growth of the sugarcane sett and shoot root systems, increased the growth of the primary shoot and stimulated more and larger secondary shoots. It also reduced populations of culturable fungi in the rhizosphere of the sett roots and reduced colonization of the sett and shoot roots by lesion nematode (Pratylenchus zeae). Exposure of the developing sett root system for 14 days to mono-cultured sugarcane soil was sufficient to significantly retard subsequent plant growth. In field experiments, fungicide and nematicide (mancozeb + aldicarb), when applied together to land under sugarcane monoculture, was as effective as fumigation in improving early sugarcane growth and increasing sugarcane yields. Rotation breaks (alternate crops, sown pasture, bare fallow) that were in place for 54 months, increased sugarcane establishment and increased sugarcane yields to levels similar to that obtained following fumigation of land under sugarcane monoculture. Fumigation of land that had been under the rotation breaks gave plant growth responses that were in addition to that achieved by the breaks alone. A mancozeb + aldicarb treatment was as effective as fumigation in increasing sugarcane yields after a bare fallow break but accounted for only a portion of the fumigation response following the crop and pasture breaks. Improved plant nutrition may be a factor in the fumigation response following the crop and pasture breaks. Plant growth responses to fumigation and the manocozeb + aldicarb treatments that were manifested in final sugarcane yields (after one years growth) were evident as plant growth responses (sett root, shoot root and primary shoot dry weight) measured 54 days after planting. The experimental results support the concept that when sugarcane is grown as a monoculture, deleterious fungi and nematodes retard plant establishment and early plant growth and that this leads to reduced sugarcane yields. [ABSTRACT FROM AUTHOR]

The survival of two species of plant parasitic nematodes: the root-lesion nematode Pratylenchus brachyurus, and the root-knot nematode Meloidogyne javanica, was evaluated in saturated atmospheres of 12 natural chemical compounds. The infectivity of two isolates of arbuscular mycorrhizal fungi: Glomus mosseae and Glomus intraradices, under identical experimental conditions, was also determined. All the compounds tested exerted a highly significant control against M. javanica and among them, benzaldehyde, salicilaldehyde, borneol, p-anisaldehyde and cinnamaldehyde caused a mortality rate above 50% over P. brachyurus. The infectivity of G. intraradices was inhibited by cinnamaldehyde, salicilaldehyde, thymol, carvacrol, p-anisaldehyde, and benzaldehyde, while only cinnamaldehyde and thymol significantly inhibited mycorrhizal colonization by G. mosseae. [ABSTRACT FROM AUTHOR]

A strain of the fungus Fusarium equiseti isolated from soybean cyst nematode secretes nematode-antagonistic compounds. Bioassay-guided fractionation of an extract of the culture broth was undertaken to identify the compounds. Fractions were assayed for activity against a root-knot nematode (Meloidogyne incognita), a plant pathogen that attacks the roots of numerous plant species. Two trichothecene compounds were isolated that inhibited egg hatch and immobilized second-stage juveniles of this nematode: 4,15-diacetoxy-12,13-epoxy-3,7-dihydroxytrichothec-9-en-8-one (4,15-diacetylnivalenol) and 4,15-diacetoxy-12,13-epoxy-trichothec-9-en-3-ol ( diacetoxyscirpenol). This is the first published report of these compounds affecting plant-parasitic nematodes. [ABSTRACT FROM AUTHOR]

The potential of tissue amendments from a variety of wild and cultivated Brassica spp. to kill the root lesion nematode ( Pratylenchus neglectus) in soil was assessed in laboratory experiments. Soil amended with leaf tissues was highly nematicidal, killing 56.2–95.2% of exposed nematodes. Amendment with root tissues was less effective, causing 0–48.3% mortality. Little of the suppressive impact by leaf tissues could be related to either total contents or any individual glucosinolate as determined by HPLC analysis. While the levels of total glucosinolates within root amendments had a nonsignificant relationship to nematode mortality, levels of 2-phenylethyl glucosinolate within root amendments significantly correlated with nematode suppression ( P < 0.001). Amendment of soils with equimolar levels of purified 2-phenylethyl isothiocyanate resulted in comparable levels of nematode mortality, suggesting that 2-phenylethyl glucosinolate has a role in the suppressive impact of Brassica spp. root tissues. [ABSTRACT FROM AUTHOR]

The effect of Streptomyces spp. (netted scab) on the growth of potato was investigated in three pot experiments, in two of which the effect of Verticillium dahliae was also assessed. The netted scab organisms attacked all underground plant parts of susceptible potato cultivars early in the growing season; the roots were especially seriously attacked, markedly reducing tuber yield and number but prolonging the duration of the growing season. The nematicide oxamyl had little effect on the incidence of netted scab. Repeated growing of the susceptible cv. Bintje greatly increased soil contamination with the netted scab pathogens. V. dahliae reduced haulm growth before wilt symptoms were evident and it reduced tuber yield but not number. Oxamyl delayed infection by V. dahliae by controlling parasitic Pratylenchus nematodes (mainly P. thornei). [ABSTRACT FROM AUTHOR]

The extent to which cultural control measures could be used to reduce the need for nematicides was examined in field experiments on vegetable crops in Bundaberg, Queensland. Evaluation of the twelve most common vegetable crops grown in the region showed that all were susceptible to root-knot nematodes ( Meloidowe spp.), as nematode multiplication occurred on all crops. Tomato, pumpkins, rockmelons, watemelons, eggplant and zucchini infested with Meloidogynes pp. yielded 15-36% less than nematode-free plants, whereas yields of sweetcorn, capsicum, french bean, chinese cabbage, broccoli and button squash were not markedly affected by the nematode. Results of experiments in which tomatoes were planted at different times of the year showed that root-knot nematode reduced yields by 16-36% when crops matured in summer. Yield reductions from nematodes were either not observed in winter or the losses were less important because of the higher yields that are achievable at this time of the year. These results suggest crop rotation and adjustment of planting time could possibly be used to reduce the economic impact of root-knot nematodes on vegetable production. Susceptible but tolerant crops (e.g. sweetcorn and capsicum) would be grown during the summer whereas susceptible intolerant crops (e.g, tomato) are best confined to the autumn-winter period. [ABSTRACT FROM AUTHOR]

Concentrations of phenamiphos ranging from 0 to 40 μrg/g soil were established in a typical Oxisol (Tropeptic Eutrustox), inoculated or uninoculated with Glomus aggregatum. The effect of the nematicide on the development of vesicular-arbuscular mycorrhizal (VAM) symbiosis was evaluated in the greenhouse using Leucaena leucocephala as an indicator host plant. Treatment of soil with phenamiphos did not have a significant influence on the development of mycorrhizal activity measured in terms of subleaflet phosphorus concentrations. Similarly, the nematicide did not have an adverse effect on the level of mycorrhizal colonization or on the P content of shoots, as determined at the time of harvest. However, shoot dry weight was adversely influenced by phenamiphos when the chemical was applied to the uninoculated soil at 20 μg/g soil or higher, and when it was applied to the inoculated soil at 40 μg/g soil. It is concluded that phenamiphos is not likely to influence the growth of Leucaena or its symbiotic association with VAM fungi if the concentrations applied do not exceed levels known to suppress nematodes. [ABSTRACT FROM AUTHOR]

The effect of 24 treatment combinations of cultures of Streptomyces costaricanus sp. nov. (ATCC55274), Bacillus thuringiensis (ATCC55273) and a strain of Paecilomyces marquandii, nematicide (cadusaphos), and/or wheat mash on growth and response of potted banana plants (Musa AAA) and populations of Radopholus similis, Helicotylenchus multicinctus and free living nematodes were studied in Río Frío, Costa Rica. The best plant responses (height, leaf numbers, healthy root weight), lowest numbers of plant parasitic nematodes and highest numbers of free living nematodes were observed for treatments containing wheat as a component. Two treatments, viz. wheat + Streptomyces costaricanus (200-ml culture) and wheat + P. marquandii (200-ml culture), gave the overall best results. Numbers of free living nematodes increased up to 1500-fold only for treatments containing wheat. Significant positive correlations existed between numbers of free living nematodes and shoot weight, healthy root biomass, plant height, and leaf numbers. Non-wheat treatments, including nematicide only, gave the poorest responses in general. Observations of nematodes sampled 50 days following planting in wheat-containing treatments showed most of the free-living nematodes (≈ 90%) to be infected by nematophagous fungi (species not recorded). The results show that an organic amendment to soil, with or without a microbial component, can be an effective inducer of processes that regulate plant-parasitic nematode populations in soil. [ABSTRACT FROM AUTHOR]

A comparative study of different application methods of nematicide C-Fosthiazate was done for the uptake in tomato plants in two varieties Pusa Ruby and Pusa Early Dwarf. The application methods used for the research purpose are seed treatment, soil supplication and drip application in presence and absence of surfactant (Tween-80).It as found that percent absorption was the highest in the drip irrigation method in presence of surfactant. The percent uptake of C-Fosthiazate in two varieties of tomato plants was found to be higher in Pusa Early Dwarf in all the treatment methods. [ABSTRACT FROM AUTHOR]

The nematicidal effect of three marine algal, Ulva fasciata Delile (UF) (green algae), Corallina mediterranea, Corallina officinalis (red algae), extracts on egg hatching and second-stage juveniles (J2) mortality of root-knot nematode (Meloidogyne incognita) in vitro compared to the nematicide activity of Oxamyl 24% SL (5 ml/l) was investigated. Results revealed that all treatments at the applied concentrations suppressed the egg hatching in 3 days. In details, the algal strain Ulva fasciata Delile extract showed the highest activity in decreasing the eggs hatchability after 3 days with 87%. Consequently, all treatments significantly increased the mortality of J2 larvae after 12, 24, and 48 h compared to the control treated with distilled water. Under greenhouse conditions, all treatments in inoculated soils cultivated with tomato plants had reduced numbers of galls, egg-masses/plant, and the number of J2/250 g than the non-inoculated soil. The algal extract and the Oxamyl 24% SL (5 ml/l) increased the length and fresh weight of plant shoots and roots than the untreated. However, there were no differences in shoots and roots fresh weights and their lengths in the plant treated with Oxamyl 24% SL (5 ml/l) or the extracts of U. fasciata and Corallina officinalis. These results were closely similar to control. Both of peroxidase and polyphenol enzymes activity for the control plants remained relatively stable, while the activity of the two enzymes in the plant inoculated with the nematode decreased during 2 to 18 day post inoculation (dpi). These activities increased in inoculated plants treated with C. officinalis, C. mediterranea, and U. fasciata extracts and the other plants treated with Oxamyl 24% SL (5 ml/l). The maximum activity of the three enzymes was recorded at 5 dpi after treatment with U. fasciata. [ABSTRACT FROM AUTHOR]