الفهرس 
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Abstract
This study aimed to: 1)The effectiveness of P. fluorescens and eight rhizobacteria isolates on egg hatching inhibition and juveniles mortality of M. incognita revealed the suppressive activity of all bacterial isolates against juveniles mobility increased gradually with the increment of the exposure periods. All bacterial isolates were found to cause substantial mortality to second stage juveniles (J2) with percentages in juveniles mortality ranged from 39.0-60.0% at the three periods of exposure. All bacterial isolates exhibited the potential to suppress egg hatching (27.6-54.0%) after 10 days of exposure and increase juvenile mortality (55.5- 60.0%) after 72hr of exposure. The two potent bacteria i.e.2KT and 3SN exhibited strong activity against egg hatching and juvenile survival were identified as B. subtilis and P. aeruginosa. 2)The impact of three native rhizobacteria namely: Pseudomonas fluorescens, Bacillus subtilis and Pseudomonas aeruginosa, applied as root dipping, on plant growth response of tomato cv. Amikodor and M. incognita reproduction was undertaken. The three biocontrol agents induced a significant increment in all plant growth characters with different extent. P. aeruginosa ranked the first and caused considerable improvement in shoot length (113.9%); total plant fresh weight (155.4%) followed by B. subtilis (141.5%) P. fluorescens (138.4%) in total plant fresh weight. Root dipping in bioagents resulted a remarkable suppression in nematode population densities in soil. The highest percentages of reduction was recovered with P. fluorescens (31.2 %) followed by B. subtilis(27.3%) and P. aeruginosa (23.88%). 3)The effectiveness of P. fluorescens, B. subtilis and P. aeruginosa applied as root dipping + soil drenching on root-knot nematode, M. incognita population densities and the consequent effect on plant growth characters (shoot length, plant biomass and dry shoot weight) was documented. Plant biomass and dry shoot weight were also significantly improved with P. aeruginosa and P. fluorescens, and B. subtilis. Among the three soil bacteria, nematode population densities of M. incognita whether in soil and root were significantly suppressed with the application of P. aeruginosa (Rf= 0.88) However, the least efficient soil bacterium was recovered with B. subtilis (Rf= 1.08). Irrespective to application method nematode fecundity in terms of number of egg masses and number of eggs/single egg mass was significantly suppressed by such treatments.4). The impact of P. fluorescens, B. subtilis and P. aeruginosa applied singly and in combination on tomato plant characters and nematode population densities was undertaken. Introduction of selected rhizobacteria singly and in combination gave promising results as compared with control. Shoot lengths and plant biomass of tomato were significantly induced with all applications of rhizobacteria. Among single application, performed the best and recorded a remarkable induction in shoot length (67.4%); total plant fresh weight (107.3%) and shoot dry weight (68.3%).Data revealed that combined applications gave better results than did single ones. Meanwhile, pots receiving the two pseudomonad species and B. subtilis gave significant augmentation in shoot length (80.5%), total plant fresh weight (134.0%) and dry shoot weight (72.8%) exceeded those of dual and single application. 5)The impact of neem as organic amendment on the biocontrol activity of the rhizobacteria namely P. fluorescens, B. subtilis and P. aeruginosa and their potentials as plant growth promoters to tomato plant infected with M. incognita is elucidated. Results revealed that pots receiving single application of dried leaf powder of neem showed in significant induction in growth response of tomato infected with M. incognita as compared with untreated inoculated control.