Biological control using rhizosphere bacteria, Pseudomonas spp. and Serratia spp. is a prospective alternative technique to overcome plant parasitic nematodes infection. So, the current study was conducted in vitro on five egg-masses, 100 free eggs and 100 infective juveniles (IJs) of Meloidogyne incognita as well as greenhouse treatments on Luffa aegyptiaca L. to evaluate the nematicidal potential of six strains belong to Pseudomonas spp. and Serratia spp. as compared to oxamyl. Results showed that the inhibitory effect and juvenile mortality varied according to bacteria species, strains and exposure time. All the tested bacteria significantly ( P ≤ 0.05) inhibited egg hatching and increased juvenile mortality in vitro . After 3 days of treatment, Pseudomonas spp. were more effective against eggs (48.31to 55.15%) and IJs (20.98 to 25.30%) than Serratia spp. (44.55 to 49.75% with eggs) and (19.06 to 21.61% with IJs), respectively. In the pot experiment, Luffa aegyptiaca L. treated with Serratia spp. and Pseudomonas spp. displayed significantly higher ( P ≤ 0.05) levels of growth (as indicated by root length, fresh roots weight and fresh shoots weight) compared to control plants and significantly ( P ≤ 0.05) suppressed galling (number of galls) and reproduction (as indicated by number of egg-masses on roots and number of eggs and juveniles in pot soil). Meanwhile, among the treated plants, Serratia spp. and Pseudomonas spp. gave the best results in shoot weight of pots infected by eggs of M. incognita than those infected with IJs as compared with positive control. While, oxamyl treatment gave the best results in pots infected by eggs and IJs. The lowest galling (gall index), number of eggs and juveniles in soil was observed in the treatment with mixture of Serratia spp. and Pseudomonas spp. as well as, enhanced growth of sponge gourd more than application each of them alone. Pots treated with oxamyl overwhelmed those treated with mixture of Serratia spp. and Pseudomonas spp.

A greenhouse experiment was carried out to evaluate the nematicidal activity of animal manures viz. chicken and goat manures, biopesticides viz. bio-zeid and nemex against Meloidogyne incognita infecting three cucurbits compared with oxamyl. Cucurbit plants namely cucumber (Cucumis sativus L.) cv. Biet Alpha, squash (Cucurbita pepo L.) cv. Escandrany and watermelon (Citrullus lanatus) cvs. Master and. Mloky were chosen for this study. Results indicated that of five tested materials, oxamyl, chicken and goat manures were the most effective in suppressing root galling and number of egg masses of M.incognita infecting cucurbit plants. Oxamyl (69.22%), chicken (60.98%) and goat (56.60 %) manures showed better performance in reducing root galling on cucumber than did on squash. Among the two cultivars of watermelon, the effectiveness of oxamyl (70.75), chicken (52.29) and goat (49.22%) manures were more pronounced on Master than on Mloky cultivar with root galling reached 50.74, 28.36 and 23.88% respectively. On the other hand, all treatments showed significant (P ≤ 0.05) improvement in cucurbits to certain extent. The maximum percentage of increase in shoot fresh weight was recorded on cucumber (93.30; 74.76%) and watermelon cv. Mloky (92.74; 76.81%) in pots receiving oxamyl and chicken manure, respectively. In general, number of galls showing fewer and smaller gall diameter (˂ 2 mm) was significantly decreased by oxamyl, chicken and goat manures in the three plant species. Our results showed that chicken and goat manures could be used to increase crop yield of cucurbit plants and for controlling root-knot nematode, M.incognita .

The suppressive effects of six species of entomopathogenic nematodes (EPNs) against Meloidogyne incognita infected tomato were assessed in two separate trials under greenhouse conditions. The tested EPN species were Heterorhabditis bacteriophora, H. megidis, H. zealandica, Steinernema feltiae, S. glaseri and S. riobravae. In the first trial, EPNs were applied as a liquid suspension of alive or dead infective juveniles (IJs) at rate of 5000 IJs/plant in sandy and clay soils, while in the second trial, two Galleria mellonella infected cadavers of six-day old per plant were used in sandy soil. In the two experiments, application of EPNs was accomplished simultaneously with inoculation of M. incognita. Carbofuran as a standard synthetic nematicide was used as comparison treatment at recommended rate of 0.2 g/plant. Control treatments received only water and M. incognita at rate of1000 IJs/plant. Two months after inoculation, galling (as indicated by number of galls/plant) and reproduction (as indicated by number of egg masses /plant) as well as damage (as indicated by fresh and dry weight of areal parts) were assessed. Data showed that, treatment of carbofuran surpassed all other treatments in minifying galling and reproduction of M. incognita in sandy and clay soils. On the other hand, curative applications of alive or heat-killed IJs significantly (P≤ 0.05) diminished gall formation and egg mass production in tomato roots with slightly amelioration in fresh and dry weight of tomato shoot. Steinernematid species were more comparatively effective than heterorhabditid ones. General means for number of galls and egg masses for steinernematid species were 52.50 and 25.33 with percent reduction of 55.45 and 64.49 %, respectively. Whereas, the parallel values for heterorhabditid species were 69.67 and 36.33 with percent reduction of 40.88 and 49.07%, respectively compared to treatment of M. incognita alone. Treatments of alive IJs overwhelmed those of dead IJs in decreasing number of galls (with percent reduction of 56.53 and 39.79% respectively) and egg masses (with percent reduction of 63.16 and 50.39%, successively). Moreover, utilization of two G. mellonella infected cadavers markedly lowered number of galls and egg masses

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This study was carried out to determine the nematicidal efficiency of seven bionematicides (Nema end, Nema cont, Nema clean, Nema K, Bio-zeid, Bio-arc and Nemex) compared with one nematicide (Nemacur 10%) on three cultivars of tomato against the root-knot nematode (RKN) Meloidogyne incognita under greenhouse conditions. The screened tomato cultivars (endless summer, supermarmand and jueblle) were significantly different in their response to nematode infection. Detectable tolerance to nematode infection was recorded with cultivar Endless summer and Juebelle while the least tolerance was recorded with supermarmand cultivar. Number of galls and egg masses were significantly decreased in the investigated cultivars treated with Nemacur, and Nema k,