Meloidogyne javanica Parasitic on Peanut

Peanut fields in four governorates of Egypt were surveyed to identify species of Meloidogyne present. Fourteen populations obtained from peanut roots were all identified as M. javanica based on perineal patterns, stylet and body lengths of second-stage juveniles, esterase phenotypes, and restriction fragment length polymorphisms of mtDNA. Three of 14 populations, all from contiguous fields in the Behara governorate, had individuals with a unique two-isozyme esterase phenotype. All populations of M. javanica tested on peanut had levels of reproduction on the M. arenaria-susceptible peanut cultivar Florunner that were not different from M. arenaria (P = 0.05), and had lower levels of reproduction on the M. arenaria-resistant genotype TxAG-7 than on Florunner (P = 0.05). Reproduction of the five Egyptian populations of M. javanica tested was lower on root-knot nematode resistant tomato cultivars Better Boy and Celebrity than on the root-knot nematode susceptible cultivar Rutgers (P = 0.05). These data are evidence that some populations of M. javanica are parasitic on peanut and that the peanut and tomato genotypes resistant to M. arenaria are also resistant to these populations of M. javanica.     

Are Pathogenesis-Related Proteins Induced by Meloidogne javanica or Heterodera avenae lnvasion?

Changes in root- and leaf-soluble proteins were investigated in tomato after invasion by the root-knot nematode Meloidogyne javanica, or in barley and wheat after invasion by the cereal cyst nematode Heterodera avenae. Infection of susceptible tomato plants by M. javanica did not cause any change in the soluble-protein composition of leaves or roots compared with uninoculated plants at an early infection stage. No pathogenesis-related proteins (chitinase, glucanase, or P-14) were induced in the leaf apoplast. Changes in leaf proteins were not observed after invasion of wheat cultivars by H. avenae, whereas, in barley, a few changes in intercellular leaf proteins were recorded in resistant cultivars. These changes, however, were not the same among different H. avenae-resistant cultivars. Protein changes were found at an early stage of infection in barley and wheat roots infected with H. avenae, but no difference was found between resistant and susceptible cultivars.     

Evaluation of 31 Potential Biofumigant Brassicaceous Plants as Hosts for Three Meloiodogyne Species

Brassicaceous cover crops can be used for biofumigation after soil incorporation of the mowed crop. This strategy can be used to manage root-knot nematodes (Meloidogyne spp.), but the fact that many of these crops are host to root-knot nematodes can result in an undesired nematode population increase during the cultivation of the cover crop. To avoid this, cover crop cultivars that are poor or nonhosts should be selected. In this study, the host status of 31 plants in the family Brassicaceae for the three root-knot nematode species M. incognita, M. javanica, and M. hapla were evaluated, and compared with a susceptible tomato host in repeated greenhouse pot trials. The results showed that M. incognita and M. javanica responded in a similar fashion to the different cover cultivars. Indian mustard (Brassica juncea) and turnip (B. rapa) were generally good hosts, whereas most oil radish cultivars (Raphanus. sativus ssp. oleiferus) were poor hosts. However, some oil radish cultivars were among the best hosts for M. hapla. The arugula (Eruca sativa) cultivar Nemat was a poor host for all three nematode species tested. This study provides important information for chosing a cover crop with the purpose of managing root-knot nematodes.     

Identification of Sources of Resistance to Four Species of Root-knot Nematodes in Tobacco

Resistance to the southern root-knot nematode, Meloidogyne incognita races 1 and 3, has been identified, incorporated, and deployed into commercial cultivars of tobacco, Nicotiana tabacum. Cultivars with resistance to other economically important root-knot nematode species attacking tobacco, M. arenaria, M. hapla, M. javanica, and other host-specific races of M. incognita, are not available in the United States. Twenty-eight tobacco genotypes of diverse origin and two standard cultivars, NC 2326 (susceptible) and Speight G 28 (resistant to M. incognita races 1 and 3), were screened for resistance to eight root-knot nematode populations of North Carolina origin. Based on root gall indices at 8 to 12 weeks after inoculation, all genotypes except NC 2326 and Okinawa were resistant to M. arenaria race 1, and races 1 and 3 of M. incognita. Except for slight root galling, genotypes resistant to M. arenaria race 1 responded similarly to races 1 and 3 of M. incognita. All genotypes except NC 2326, Okinawa, and Speight G 28 showed resistance to M. javanica. Okinawa, while supporting lower reproduction of M. javanica than NC 2326, was rated as moderately susceptible. Tobacco breeding lines 81-R-617A, 81-RL- 2K, SA 1213, SA 1214, SA 1223, and SA 1224 were resistant to M. arenaria race 2, and thus may be used as sources of resistance to this pathogen. No resistance to M. hapla and only moderate resistance to races 2 and 4 of M. incognita were found in any of the tobacco genotypes. Under natural field infestations of M. arenaria race 2, nematode development on resistant tobacco breeding lines 81-RL-2K, SA 1214, and SA 1215 was similar to a susceptible cultivar with some nematicide treatments; however, quantity and quality of yield were inferior compared to K 326 plus nematicides.     

Effects of the Mi-1 and the N root-knot nematode-resistance gene on infection and reproduction of Meloidogyne enterolobii on tomato and pepper cultivars

Meloidogyne enterolobii is widely considered to be an aggressive root-knot nematode species that is able to reproduce on root-knot nematode-resistant tomato and pepper cultivars. In greenhouse experiments, M. enterolobii isolates 1 and 2 from Switzerland were able to reproduce on tomato cultivars carrying the Mi-1 resistance gene as well as an N-carrying pepper cultivar. Reproduction factors (Rf) ranged between 12 and 109 depending on the plant cultivar, with M. enterolobii isolate 2 being more virulent when compared to isolate 1. In contrast, M. arenaria completely failed to reproduce on these resistant tomato and pepper cultivars. Although some variability in virulence and effectiveness of root-knot nematode-resistance genes was detected, none of the plant cultivars showed Rf values less than 1 or less than 10% of the reproduction observed on the susceptible cv. 'Moneymaker' (Rf = 23-44) used to characterize resistance. The ability of M. enterolobii to overcome the resistance of tomato and pepper carrying the Mi-1 and the N gene makes it difficult to manage this root-knot nematode species, particularly in organic farming systems where chemical control is not an option.     

Role of cyanide production by Pseudomonas fluorescens CHA0 in the suppression of root-knot nematode, Meloidogyne javanica in tomato

Summary Pseudomonas fluorescens strain CHA0 produces hydrogen cyanide (HCN), a secondary metabolite that accounts largely for the biocontrol ability of this strain. In this study, we examined the role of HCN production by CHA0 as an antagonistic factor that contributes to biocontrol of Meloidogyne javanica, the root-knot nematode, in situ. Culture filtrate of CHA0, resulting from 1/10-strength nutrient broth yeast extract medium amended with glycine, inhibited egg hatch and caused mortality of M. javanica juveniles in vitro. The bacterium cultured under high oxygen-tension conditions exhibited better inhibitory effects towards nematodes, compared to its cultivation under excess oxygen situation. Growth medium amended with 0.50 or 1.0 mM FeEDDHA further improved hatch inhibition and nematicidal activity of the strain CHA0. Strain CHA77, an HCN-negative mutant, failed to exert such toxic effects, and in this strain, antinematode activity was not influenced by culture conditions. Exogenous cyanide also inhibited egg hatch and caused mortality of M. javanica juveniles in vitro. Strains CHA0 or CHA77 applied in unsterilized sandy-loam soil as drench, caused marked suppression of root-knot disease development incited by M. javanica in tomato seedlings. However, efficacy of CHA77 was noticeably lower compared to its wild type counterpart CHA0. An increased bioavailability of iron following EDTA application in soil substantially improved nematode biocontrol potential of CHA0 but not that of CHA77. Soil infestation with M. javanica eggs resulted in significantly lower nematode population densities and root-knot disease compared to the juveniles used as root-knot disease-inducing agents. Strain CHA0 significantly suppressed nematode populations and inhibited galling in tomato roots grown in soil inoculated with eggs or juveniles and treated with or without EDTA. Strain CHA0 exhibited greater biocontrol potential in soil inoculated with eggs and treated with EDTA. To demonstrate that HCN synthesis by the strain CHA0 acts as the inducing agent of systemic resistance in tomato, efficacy of the strain CHA0 was compared with CHA77 in a split root trial. The split-root experiment, guaranteeing a spatial separation of the inducing agent and the challenging pathogen, showed that HCN production by CHA0 is not crucial in the induction of systemic resistance in tomato against M. javanica, because the HCN-negative-mutant CHA77 induced the same level of resistance as the wild type but exogenous cyanide in the form of KCN failed to trigger the resistance reaction. In the root section where both nematode and the bacterium were present, strain CHA0 reduced nematode penetration to a greater extent than CHA77, suggesting that for effective control of M. javanica, a direct contact between HCN-producing CHA0 and the nematode is essential.     

Bacillus halotolerans strain LYSX1-induced systemic resistance against the root-knot nematode Meloidogyne javanica in tomato

Purpose

Determination of the nematicidal potential and mode of action of bacteria isolated from tobacco rhizosphere soil against the root-knot nematode Meloidogyne javanica in tomato plants.

Methods

Antagonistic bacteria were isolated from rhizosphere soil of tobacco infested with root-knot nematodes. Culture filtrate was used to examine nematicidal activity and ovicidal action of bacterial strains. Biocontrol of M. javanica and growth of treated tomato plants were assessed in pot experiments. To clarify whether secondary metabolites of bacteria in tomato roots induced systemic resistance to M. javanica, bacterial culture supernatants and second-stage juvenile nematodes were applied to spatially separated tomato roots using a split-root system. Bacterial strains were identified by 16S rDNA and gyrB gene sequencing and phylogenetic analysis.

Results

Of the 15 bacterial strains isolated, four (LYSX1, LYSX2, LYSX3, and LYSX4) demonstrated nematicidal activity against second-stage juveniles of M. javanica, and strain LYSX1 showed the greatest antagonistic activity; there was dose-dependent variability in nematicidal activity and inhibition of egg mass hatching by strain LYSX1. In vivo application of LYSX1 to tomato seedlings decreased the number of egg masses and galls and increased the root and shoot fresh weight. Treatment of half of the split-root system with LYSX1 reduced nematode penetration to the other half by 41.64%. Strain LYSX1 was identified as Bacillus halotolerans.

Conclusion

Bacillus halotolerans LYSX1 is a potential microbe for the sustainable biocontrol of root-knot nematodes through induced systemic resistance in tomato.

     

Macrophomina phaseolina – Meloidogyne javanica disease complex in balsam (Impatiens balsamina): a new report

Balsam seedlings were inoculated with root-knot nematode Meloidogyne javanica Race-2 and Macrophomina phaseolina either individually or concomitantly, as well as sequentially with an interval of 15?days between the nematode or fungal inoculations to determine whether the interaction was concomitant or sequential. The greater reduction in plant growth characters was observed in the plants inoculated with M. javanica and M. phaseolina, either concomitantly or sequentially as compared to their individual inoculation. However, the highest reduction in plant growth characters were recorded in the plants inoculated with M. javanica Race-2 15?days prior to M. phaseolina followed by concomitant-inoculated M. javanica Race-2 and M. phaseolina, and M. phaseolina 15?days prior to M. javanica. The number of galls/root system and the reproduction factor of the root-knot nematode was reduced in the presence of root-rot fungus. The intensity of root-rot caused by M. phaseolina increased in the presence of root-knot nematode M. javanica as compared to when M. phaseolina was inoculated individually. Moreover, stem and collar-rot symptoms caused by M. phaseolina appeared only in the presence of root-knot nematode.     

Biological control of root rot-root knot disease complex of tomato

Efficacy of Pseudomonas aeruginosa alone or in combination with Paecilomyces lilacinus was evaluated in the control of root-knot nematode and root-infecting fungi under laboratory and field conditions. Ethyl acetate extract (1 mg/ml) of P. lilacinus and P. aeruginosa,respectively, caused 100 and 64% mortality of Meloidogyne javanica larvae after 24 h. Ethyl acetate fractions of biocontrol agents were more effective than hexane extracts in the suppression of M. javanica larvae, indicating that active nematicidal compounds are intermediary in polarity. In field experiments, biocontrol fungus and bacterium significantly suppressed soilborne root-infecting fungi including Macrophomina phaseolina, Fusarium oxysporum, Fusarium solani, Rhizoctonia solani and Meloidogyne javanica, the root-knot nematode. P. lilacinus parasitized eggs and female of M. javanica and this parasitism was not significantly influenced in the presence of P. aeruginosa. P. aeruginosa was reisolated from the inner root tissues of tomato, whereas P. lilacinusdid not colonize tomato roots. This revised version was published online in June 2006 with corrections to the Cover Date.     

Evaluation of pomegranate (Punica granatum L. var. Gabsi) peel extract for control of root-knot nematode Meloidogyne javanica on tomato

The present study was carried out to assess the nematicidal potential of Punica granatum L. against the root-knot nematode Meloidogyne javanica responsible for yield losses in tomato. Varied concentrations of methanolic, ethanolic and aqueous extracts from pomegranate peels were investigated for activity against eggs and juveniles of M. javanica in in vitro assays. All extracts used significantly inhibited egg hatch by over than 75%, but viability of second-stage juveniles (J2) was not significantly inhibited by ethanolic extract. Aqueous extract was assessed at the concentration of 10, 25 and 50% against M. javanica on tomato in greenhouse trials; pomegranate peels powder was also tested at the rate of 3, 6 and 9 g as a soil amendment. Both extracts significantly reduced nematode infestations; aqueous extract enhanced plant growth but powder amendment exhibited a phytotoxicity compared to the untreated plants. The reduction in number of galls, egg masses and nematode reproduction rate was recorded.     

Effects on plant growth and root-knot nematode infection of an endophytic GFP transformant of the nematophagous fungus Pochonia chlamydosporia

Pochonia chlamydosporia (Pc123) is a fungal parasite of nematode eggs which can colonize endophytically barley and tomato roots. In this paper we use culturing as well as quantitative PCR (qPCR) methods and a stable GFP transformant (Pc123gfp) to analyze the endophytic behavior of the fungus in tomato roots. We found no differences between virulence/root colonization of Pc123 and Pc123gfp on root-knot nematode Meloidogyne javanica eggs and tomato seedlings respectively. Confocal microscopy of Pc123gfp infecting M. javanica eggs revealed details of the process such as penetration hyphae in the egg shell or appressoria and associated post infection hyphae previously unseen. Pc123gfp colonization of tomato roots was low close to the root cap, but increased with the distance to form a patchy hyphal network. Pc123gfp colonized epidermal and cortex tomato root cells and induced plant defenses (papillae). qPCR unlike culturing revealed reduction in fungus root colonization (total and endophytic) with plant development. Pc123gfp was found by qPCR less rhizosphere competent than Pc123. Endophytic colonization by Pc123gfp promoted growth of both roots and shoots of tomato plants vs. uninoculated (control) plants. Tomato roots endophytically colonized by Pc123gfp and inoculated with M. javanica juveniles developed galls and egg masses which were colonized by the fungus. Our results suggest that endophytic colonization of tomato roots by P. chlamydosporia may be relevant for promoting plant growth and perhaps affect managing of root-knot nematode infestations.     

南方根结线虫对不同砧木嫁接番茄苗活性氧清除系统的影响

采用盆栽人工接种方法,对番茄嫁接苗进行了抗性评价,研究了番茄嫁接苗叶片中抗氧化酶活性和活性氧代谢的动态变化。结果表明,接种南方根结线虫(J2)后,砧木嫁接苗表现为高抗,自根嫁接苗为高感。通过嫁接换根,与自根嫁接苗相比,砧木嫁接苗明显提高了接穗叶片的超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性,降低了超氧阴离子(O.2-)产生速率以及过氧化氢(H2O2)和丙二醛(MDA)含量。表明番茄植株体内的活性氧水平和抗氧化酶活性的高低与其抗根结线虫的能力密切相关,较低的活性氧水平和较高的抗氧化酶活性有利于减轻对膜系统的伤害,提高番茄植株的抗根结线虫能力。     

Field assessment of efficacy of nitrogen salts to control the root-knot nematode (Meloidogyne javanica) on tomato

Influence of different nitrogen salts at electrical conductivity levels (EC2, 4 and 8?mmhos/cm) on tomato and root-knot nematode (Meloidogyne javanica) and their interactions was evaluated under field conditions. It was found that both diammonium phosphate ((NH₄)₂HPO₄) and ammonium sulphate ((NH₄)₂SO₄) were more effective than ammonium chloride (NH₄Cl) in causing an obvious suppression of M. javanica infection on tomato through reducing root galling and nematode reproduction and improving tomato growth and yield and their suppressive effect was similar to that of oxamyl or ethoprophos. At higher ECs, the tested nitrogen salts did not greatly affect pH, EC and salinity of rhizospheric soil except NH₄Cl at EC8 that caused higher EC and salinity over the untreated control which makes NH₄Cl less suitable candidate. Therefore, the use of (NH₄)₂HPO₄ and (NH₄)₂SO₄ alone or in combination with other control measures could control M. javanica and improve the growth and yield of tomato under field conditions.     

Interaction of vesicular arbuscular mycorrhiza with root knot nematodes in tomato

Summary The interaction between the VA mycorrhizal fungus,Glomus fasciculatus and the root-knot nematodes,Meloidogyne incognita andM. javanica, and their effects on the growth and phosphorus nutrition of tomato was studied in a red sandy loam soil of pH 6.0. Inoculation of tomato roots with root-knot nematodes enhanced infection and spore production byG. fasciculatus. Inoculation of tomato plants withG. fasciculatus significantly reduced the number and size of the root-knot galls produced byM. incognita andM. javanica. Inoculation withG. fasciculatus although improved plant growth and its total phosphorus content compared to the uninoculated plants, the difference were not statistically significant.     

Resistance to Meloidogyne spp. in Allohexaploid Wheat Derived from Triticum turgidum and Aegilops squarrosa

Expression of resistance to Meloidogyne incognita and M. javanica from Aegilops squarrosa was studied in a synthetic allohexaploid produced from Triticum turgidum var. durum cv. Produra and Ae. squarrosa G 3489. The reproductive rate of different races of M. incognita and M. javanica, expressed in eggs per gram of fresh root, was low (P < 0.05) on the synthetic allohexaploid and the resistant parent, Ae. squarrosa G 3489, compared with different bread and durum wheat cultivars. Reproduction of race 2 and race 3 of M. incognita and an isolate of M. javanica was studied on the synthetic allohexaploid and seven cultivars of T. aestivum: Anza, Coker 747, Coker 68-15, Delta Queen, Double Crop, McNair 1813, and Southern Bell. The latter six cultivars are grown in the southeastern United States and reportedly were resistant to M. incognita. Significant differences (P < 0.05) were detected in nematode reproduction on the seven bread wheat cultivars. Reproduction of M. incognita race 3 and M. javanica was highest on Anza. Reproductive rates on the six southeastern United States bread wheat cultivars varied both within and among nematode isolates. The lowest reproductive rates of the three root-knot isolates were detected in the synthetic allohexaploid.     

Differential expression of root-knot nematode resistance genes in tomato and pepper: evidence with Meloidogyne incognita virulent and avirulent near-isogenic lineages

Reproduction of artificially selected near isogenic Meloidogyne incognita lineages virulent and avirulent against the Mi resistance gene of tomato was assessed on host and resistant lines and cultivars of pepper. Egg mass production following inoculation of individual potted seedlings with second-stage juveniles was studied in experiments conducted in controlled environment. Artificially selected Mi-virulent nematode populations were unable to develop on resistant pepper lines PM 217 and PM 687. This suggests that the genetic systems governing resistance to root-knot nematodes are differently expressed in tomato and pepper, in spite of the very close phylogenetic relationships and structural genomic homologies occurring between these two vegetable crops. Moreover, these artificially selected nematode populations were also found unable to develop on the susceptible pepper cultivars California Wonder and Doux Long des Landes, while their pathogenicity was not significantly affected on susceptible tomatoes. Due to the existence of naturally virulent Meloidogyne populations, these results enhance the need for a better understanding of the mechanisms involved, in order to develop new forms of management of plant resistance to root-knot nematodes.     

Interaction of Glomus mosseae and Paecilomyces lilacinus on Meloidogyne javanica of tomato

The effects of Glomus mosseae and Paecilomyces lilacinus on Meloidogyne javanica of tomato were tested in a greenhouse experiment. Chicken layer manure was used as a carrier substrate for the inoculum of P. lilacinus. The following parameters were used: gall index, average number of galls per root system, plant height, shoot and root weights. Inoculation of tomato plants with G. mosseae did not markedly increase the growth of infected plants with M. javanica. Inoculation of plants with G. mosseae and P. lilacinus together or separately resulted in similar shoots and plant heights. The highest root development was achieved when mycorrhizal plants were inoculated with P. lilacinus to control root-knot nematode. Inoculation of tomato plants with G. mosseae suppressed gall index and the average number of galls per root system by 52% and 66%, respectively, compared with seedlings inoculated with M. javanica alone. Biological control with both G. mosseae and P. lilacinus together or separately in the presence of layer manure completely inhibited root infection with M. javanica. Mycorrhizal colonization was not affected by the layer manure treatment or by root inoculation with P. lilacinus. Addition of layer manure had a beneficial effect on plant growth and reduced M. javanica infection.     

Reproduction of Meloidogyne spp. on Resistant Peanut Genotypes from Three Breeding Programs

Three described species of root-knot nematode parasitize peanut (Arachis hypogaea): Meloidogyne arenaria race 1 (Ma), M. hapla (Mh), and M. javanica (Mj). Peanut cultivars with broad resistance to Meloidogyne spp. will be useful regardless of the species present in the field. The objective of this study was to determine whether peanut genotypes with resistance to M. arenaria originating from three different breeding programs were also resistant to M. hapla and M. javanica. The experiment used a factorial arrangement (completely randomized) with peanut genotype and nematode population as the factors. The five peanut genotypes were ''COAN'' and AT 0812 (highly resistant to Ma), C209-6-13 (moderately resistant to Ma), and ''Southern Runner'' and ''Georgia Green'' (susceptible to Ma). The four nematode populations were two isolates of Ma (Gibbs and Gop) and one isolate each of Mh and Mj. On COAN or AT 0812, both Ma and Mj produced <10% of the eggs produced on Georgia Green. On the peanut genotype C209-6-13, Ma and Mj produced about 50% of the eggs produced on Georgia Green. None of the resistant genotypes exhibited a high level of resistance to Mh. The lack of resistance to Mh in any cultivars or advanced germplasm is a concern because the identity of a Meloidogyne sp. in a particular peanut field is generally not known. Breeding efforts should focus on moving genes for resistance to M. hapla into advanced peanut germplasm, and combining genes for resistance to the major Meloidogyne spp. in a single cultivar.     

Management of Fusarium oxysporum f. sp. lycopersici and root-knot nematode disease complex in tomato by use of antagonistic fungi,plant resistance and neem

Simultaneous infestation with root-knot nematodes (RKN) and Fusarium oxysporum f. sp. lycopersici (FOL) leads to formation of a disease complex that increases crop losses than effect of either RKN or FOL. In this study a management programme involving plant resistance, biological control agents, and neem was carried out to manage RKN and fusarium wilt disease complex. The biological control agents were Purpureocillium lilacinum (PL) and Trichoderma harzianum (TH) while the RKN was Meloidogyne javanica. In vitro dual culture plates were set up to test the interaction of biological control agents and FOL. Greenhouse experiments were conducted using two tomato cultivars Rambo F1 and Prostar F1. The treatments were; PL, TH, PL–TH, neem, PL neem, TH neem, and PL–TH neem. Each treatment was replicated four times and the treatments set up in a randomised complete block design in the greenhouse. Inhibition of FOL mycelial growth by TH and PL was 51.9%, and 44% respectively by the ninth day in vitro culture plates. In the cultivar, Prostar F1, the treatments PL–TH, PL, and TH in the presence or absence of neem had a FOL disease severity score significantly lower than the untreated control. Host resistance sufficed to prevent infection of Rambo F1 with FOL. The treatments PL–TH, PL and TH reduced FOL propagules and M. javanica juveniles in the roots and performed even better when combined with neem in both tomato cultivars. Therefore, a host that is resistant combined with biological control agents and organic amendments can be used in the management of RKN and FOL in tomato production.     

Potential biocontrol activity of Arthrobotrys oligospora and Trichoderma harzianum BI against Meloidogyne javanica on tomato in the greenhouse and laboratory studies

In this investigation, the biological control activity of Arthrobotrys oligospora and Trichoderma harzinum BI against the root-knot nematode, Meloidogyne javanica, infecting tomato, was assessed both in in vitro and in in vivo experiments. In greenhouse experiments, tomato seedlings at six-leaf stage were inoculated with 10⁶?spores/ml of A. oligospora and T. harzianum BI and number of 2000 nematode eggs per individual seedling. In in vitro assays, the per cent inhibition of nematode eggs hatching, the death per cent of second-stage juvenile (J2) and proteolytic activity on casein hydrolysis was evaluated. Results showed that A. oligospora and T. harzianum BI decreased the mean numbers of galls, eggmasses and egg per eggmass significantly (p?<?0.05) compared with control. Percentage hatching inhibition of M. javanica treated with A. oligospora and T. harzianum BI was 25 and 52%, respectively. Moreover, A. oligospora and T. harzianum BI significantly increased (p?<?0.05) the mortality rate of M. javanica (J2) after two and four days (74, 85 and 53, 63%, respectively). A. oligospora and T. harzianum BI had a proteolytic activity of 3.9 (U/min per ml) and 2.4 (U/min per ml) at pH 5.0, respectively. Our data suggest that the application of these two fungi in tomato rhizosphere infected with root-knot nematode M. javanica had antagonistic effects on the infection and reproduction of this nematode and the ability to control its population.